ISSN 0083-9086

THE

SCIENTIFIC REPORTS
OF

THE WHALES RESEARCH INSTITUTE
No. 32

THE WHALES RESEARCH INSTITUTETOKYO·JAPANDECE1vfBER 1980

i~Sci. R6p. Whales

!~

THE
SCIENTIFIC REPORTS
OF
THE WHALES RESEARCH INSTITUTE
No. 32

THE WHALES RESEARCH INSTITUTETOKYO, JAPANDECEMBER, 1980

THE WHALES RESEARCH INSTITUTE
1-3-1 ETCHUJIMA, KOTO-KU, TOKYO

THE SCIENTIFIC REPORTS OF THE WHALESRESEARCH INSTITUTE
CONTENTS OF NUMBER 32Page

KAWAMURA, A.
Food habits of the Bryde's whales taken in the South Pacific and Indian
oceans..........................................................
1
OMURA, H.
Morphological study of pelvic bones of the minke whale from the Antarctic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
HOHN, A. A.
Age determination and age related factors in the teeth of western North
Atlantic bottlenose dolphins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
YoNEKURA, M., S. MATSUI, and T. KAsUYA
On the external characters of Globicephala macrorhynchus off Taiji, Pacificcoast of Japan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
NEMOTO, T., P. B. BEST, K. lsHIMARU, and H. TAKANODiatom films on whales in South African waters. . . . . . . . . . . . . . . . . . . . . . 97
KAMIYA, T. and P. PIRLOT
Brain organization in Platanista gangetica . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
YAMASAKI, F., S. KOMATSU, and T. KAMIYA
A comparative morphological study on the tongues of manatee anddugong (Sirenia) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
CAsrnos, A. and J. Bou
On a massive stranding of short-finned pilot whale, Globicephala macro145
rhynchus Gray, 1846, on Margarita Island (Venezuela)
MERMOZ, J. F.
A bdef report on the behavior of commerson's dolphin, Cephalorhynchus
commersonii, in Patagonian shores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
KAWAMURA, A.
A review of food of balaenopterid whales . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
KAWAKAMI, T.
A review of sperm whale food . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199

目

次

河村章人

南太平洋及びインド洋産ニタリクジラの食性
大村秀雄

南氷洋産ミンク鯨の腰骨の形態学的研究．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

25

Hohn,A.A.
北大西洋西部におけるハンドウイルカの年令査定............................ 39

米倉学・松井進・粕谷俊雄
太地産マゴンドウの外部形態について．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．

67

根本敬久・ P.BBest−石丸君江・高野秀昭
南アフリカ沖で捕獲された鯨類に見出された珪藻.• ...............• .......... 97

神谷敏郎・ P
.P
i
r
l
o
t
ガンジスカワイルカ脳の二，三の形態学的特徴.............................. 1
0
5

山崎英雄・小松俊郎・神谷敏郎
27
海牛目（マナティ・ジュゴン）の舌の比較解剖学的研究.......................... 1

C
a
s
i
n
o
s
,A.andJ.Bou
ベネズェラにおけるマゴンドウのー記録.................................... 1
4
5

Mermoz,J.F.
パタゴニアにおけるコマーソンイルカの観察................................ 149
河村章人

ナガスクジラ科鯨類の食性総述............................................ 1
5
5

川上武彦
マッコウクジラの食性総述.............................................. 199

FOOD HABITS OF THE BRYDE'S WHALES TAKEN
IN THE SOUTH PACIFIC AND INDIAN OCEANS*
AKITO KAWAMURA
Faculty of Fisheries, Hokkaido University, Hakodate, Hokkaido

ABSTRACT

A total of 459 Bryde's whales were taken in the Coral Sea, South Pacificand Indian oceans during the seasons of 1976/77-1978/79 under the schemeof scientific permit. As one of research items on the least known baleen
whale species, food habits of the caught animals were studied on the carcasses in the field, and some 234 stomach samples out of 252 animals of filled
stomach were closely examined in the laboratory. On the whole 55% or
252 animals out of 459 were found to be retaining stomach contents with varying fulness. Analysis on stomach samples suggested that the Bryde's whales
in pelagic waters of the southern hemisphere largely prey upon the euphausiid crustaceans in stead of the fish. These evidences clearly suggest the locally abundant distributions of food organisms. The southern Bryde's whales
may be considered to live substantially on euphausiids such as Euphausia
diomedeae, E. recurva, and Thysanoessa gregaria widely in the studied area, butboth Pseudeuphausia latifrons and E. sibogae may characteristically become
more important food items than the three others in the equatorial eastern
Indian Ocean. Although the found evidence as a whole is the phenomenon
confined to somewhat local areas, both rich fulness of stomach and monospecific composition of the prey organisms suggest that those euphausiid
species may occur with fairly large biomass by forming densely aggregatedswarms even in the tropical and subtropical pelagic regions. The ecologicalimportance of euphausiid crustaceans over the warmer seas as well as those in
the colder seas is discussed.
INTRODUCTION

Since Olsen (1913) studied the Bryde's whales, Balaenoptera brydei from the South
African waters, distribution of the Bryde's whales in the southern hemisphere haslong been known but this animal remained as less known balaenopterid whales due
to rather sporadic information. Except several taxonomical studies on the stranded and/or occasionally taken animals, there has been no biological study of any extent. Recently, however, Best (1960, 1967, 1977) studied the Bryde's whalescaught off Durban and Donkergat, South Africa and found that there occurs two
allopatric forms, i.e. inshore and offshore forms. The main difference which separates the species into two forms was the morphological differences in the shape of* Abstract of this work was orally reported at the XIV Pacific Science Congress, Khabarovsk, USSR,
1979.
Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 1-23

2

KAWAMURA

baleen plates such as the width/length ratios in addition to the general biologicalcharacteristics by each form (Best, 1977). The exhibited character of baleen plates
in both forms resulted to show a considerable different food habits among them.
Best (1977) states that the inshore form feeds mainly on small gregarious fishes suchas anchovy (Engraulis capensis) and pilchard (Sardinops ocellata), while the offshore
form strongly prefers to feed upon the Euphausiacea such as Euphausia lucens. It
can be said that our knowledge on the biology of the southern species of Bryde's
whales has largely increased during the past two decades.
However, our knowledge having been obtained to date seems to be still
confined to that from local and possibly coastal stocks of this animals. The catches
at South Africa (Best, 1960), Western Australia (Chittleborough, 1959), New Zealand(Gaskin, 1972) and Chile (Aguayo, 1965) were all done by the land based whaling.
On the other hand, there occurs more larger number of Bryde's whales over thevast pelagic regions of the southern hemisphere (Gambell et al., 1974), but neither
has been studied concerning the status of possible pelagic stocks nor the biologicalcharacteristics due to the international control measures of whaling.
It has been known that the distribution of Bryde's whales are confined largely
within the temperate to tropical seas where the temperature is higher than 20°C
(Omura and Nemoto, 1955). The habitat for the Bryde's whales is quite unusual
when it is compared with the case in another balaenopterid whales, to which mostbaleen whale species may visit only for breeding.
From the viewpoints of ecological energetics, the breeding ground for thebaleen whale species cannot be considered the place of any extent of feeding, i.e.,there is no nutritional importance at all. On the other hand, some observations
strongly suggest that the feeding of balaenopterid whales may take place in thewarmer seas (Gambell et al., 1974; Masaki, 1979). The author too observed many
Bryde's whales that swam away leaving a patch of brick red feces when they werechased during the tagging investigations in the equatorial Pacific. An estimationof the energetic budget of locomotion in balaenopterid whales suggests that eventhe animals under breeding migrations to the warmer seas must perhaps feed tosome extent (Kawamura, 1975). The above mentioned facts strongly suggest that
there must exist the aggregations of possible food organisms which are available forthe baleen whales visiting those warmer waters. These, however, must be clarified by the actual observations on the collected materials and the examination of
stomach conditions of whales occurring in the warmer waters.
In order to study the southern Bryde's whales (Balaenoptera edeni) in pelagic
waters, Japanese Government granted to take specially 120 animals per fleet perseason in 1976, and the programme went on next three successive seasons, 1976/771978/79. The special permit programme for the purpose of scientific research carriedout under the supervision of the Far Seas Fisheries Research Laboratory of Fisheries
Agency, and the whole programme came to an end in 1979. A total of 459 animals
have been caught in the pelagic waters over the central South Pacific and Indian
oceans. Although there has preliminarily been reported on earlier results by separating each fishing season (e.g. Ohsumi, 1978; Kawamura, 1977), Ohsumi (1979)
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

3

finally submitted provisional report to the 3lst IWC meeting, in which he dealt
with the whole result throughout the past three seasons, and estimated a possible
harvestable quotas by the sea regions worked out. However, the food habits of the
Bryde's whales were not treated in his report since it was not the subject being
treated in the fishery biology and stock management. Therefore, this report could
be considered as one of the supplements relating to the Japanese catch of the southern Bryde's whales under the scheme of scientific permit.
MATERIAL AND METHOD
A total of 459 Bryde's whales were caught during the past three exploratory expedtions. It is, however, still unknown to date that to which forms, inshore or offshore,
the animal belongs. The overall figures for the experimental catch are given in
Table I and Fig. 1. Two factories, Tonan Maru No. 2 and Nisshin Maru No. 3 of
TABLE I.

EXPLORATORY CATCHES OF THE SOUTHERN BRYDE'S
WHALES DURING THE SEASONS, 1976/77-1978/79
No. of animal caught

SeasonSea areaMale

1976/77

1977/78
1978/79

Coral Sea
Central S.
Pacific
SW Indian
Ocean
Central S.
Pacific
E. Indian
Ocean

Total

FemaleTotal

Stomach contents
Present
(A)

A/A+B
Empty
(B)

(%)

No. ofstomachsampleexamined

3

4

7

5

2

71.43

5

66

47

113

85

28

75.22

64

61

44

105

49

56

46.67

52

72

42

114

60

54

52.63

60

61

59

120

53

67

44.17

53

263

196

459

252

207

54.90 (Av.)

234

Nippon Kyodo Hogei K. K. operated during 1976/77 season and each of them was
granted to take 120 animals. However, during the two successive seasons, there
operated only one factory, Nisshin Maru No. 3 and the catch reduced to about anhalf from that expected when programme came to an implementation in 1976, andthis resulted somewhat insufficient collection of data for the general biologicalstudy.
The observations on the stomach condition of animals were carried out on two
different basis: 1) eye observations on the carcasses in the field, and 2) more closer
examinations of the food species based on a fraction of stomach materials by random
samplings. The stomach contents were collected regardless the magnitudes offreshness and of the amount in a stomach. Observations in the field may provide
somewhat rough evidence such as an approximate amount of stomach contents interms of percent stomach volume by five different fulness and the kind of food species by rough systematic taxa such as Pisces, Euphausiacea, Amphipoda and Copepoda. In the case of Euphausiacea, however, the difference of body size by threesize classes, viz. 'large', 'medium', and 'small' were also recorded by a personel who
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

4

was skillful enough for this kind of observations. The observed records in the field
were compiled into a register format, 'Catch Records of Whales' by the whaling inspectors of the Fisheries Agency. I used some data from that records especially inconstructing the general catch figures and stomach conditions.
A total of 234 stomach contents were collected from 252 animals with filled
stomach. The collected materials preserved in 10% formalin solution were sent
to the Whales Research Institute, Tokyo, but later to Hokkaido University where
the composition of food species were studied.
RESULTa)

Catch distribution

It has long been known that the Bryde's whales occur frequently in the tropical to subtropical waters of both hemispheres where the whaling fleet passed byevery season en route to and from the Antarctic whaling ground. By taking accountof this fact but with an uncertainty as the object of mothership operation, experimenN
30°
20'

100

'17

w (jp

oo

\.;Jc:::;,, V1f

10'

3-19~7~w ~ ~ ~C\'-.-,

20'

120 animals

30°

30 X-5 XI ~/1976
29 X-18 XI
113 animals~ 1977'V
114 animals

rJ

40°
50°
60'
SO'

24-25 x 1976
~ 7 animals

20'

40'

60°

80' 100' 120° 140° 160° 1 80' 1 60' w

Fig. I. Catch areas of the Bryde's whales taken by scientific permit in the South
Pacific and Indian oceans during the seasons of 1976/77-1978/79. The shaded
area indicates heavy concentration of catches.

tal and exploratory catch investigations were carried out by setting a possible sea
regions in the South Pacific and Indian oceans. It was proved by sighting investigations that the Bryde's whales largely distribute in both South Pacific and Indian
oceans, and the latitudinal range may extend over the tropical to temperate regions. During the 1976/77-1978/79 seasons the main concentrations of Bryde's
whales were spotted in the Coral Sea, central South Pacific, and eastern andsouthwestern Indian oceans (see Ohsumi, 1978, Fig. 1).
Figure I demonstrates approximate catch areas along with related figures wherea total of 459 animals was taken during the exploratory whaling. It is obvious thatthe catches in the central South Pacific and equatorial eastern Indian oceans wereactually made being based on the sightings worked out in 1976/77 season. Except
the catch in the southwestern Indian Ocean all the rest were caught in the tropicalsea regions where the south equatorial current or its counter current prevails. The
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

5

observed surface sea temperature ranged 20.0-30.3°C during October to November.
Contrary, the region of south west Indian Ocean was operated in March when thesurface sea temperature showed 24.6-26.6°C. According to Ohsumi (1979), theaveraged body length and weight of animals by catch areas was found to be 13.05 m(15.2 tons) as the largest figure in the South Pacific, while the smallest was 12.10 m(12.36 tons) in the Indian Ocean animals (Table 2).
Comparing these figures with those having been observed in the northernequatorial to temperate Pacific (e.g. Wada, 1975; Ohsumi, 1978; Masaki, 1979),
it may be considered that the Bryde's whales seem to distribute with somewhat
biantitropical pattern over the both hemispheres.
TABLE 2. THE AVERAGE BODY LENGTH OF SOUTHERN BRYDE'S
WHALES BY THE SEA AREAS (AFTER OHSUMI, 1979, TABLE 13)
Sea area

Indian"'S. Pacific**Total

No. of whales caught
Total average body length (m)Estimated average body weight (ton)

225
12.10
12.36

235
13.05
15.12

459
12.58
13.66

* Baths outhwestern and eastern areas of the Indian Ocean are combined.
** Coral Sea animals are included.

TABLE 3. STOMACH CONDITIONS OF THE BRYDE'S WHALES IN THE SOUTHERNHEMISPHERE. THE QUANTITY OF FOOD IS APPROXIMATED BY THE VOLUMESOF BOTH STOMACH AND THE AMOUNT OF CONTENTS
WhalinggroundSW Indian
E Indian
Coral Sea
CentralPacific
CentralPacific
Total
Percentb)

Quantity less than :Food species

Total

SeasonEuphausiacea Pisces1976/77
1978/79
1976/77

49
46
5

1976/7785

1977/78

7

60
245
96.8

8
3.2

Empty

25%

50%

75%

100%

56
67
2

21
16
2

lO
24
l

1
lO
l

17
3

105
120
7

28

47

19

12

7

113

53

28

15

9

9

114

206
44.9

114
24.8

69
15.0

33
7.2

37
8.1

459
100.0

Stomach condition

The stomach condition in general was observed in the field. The catch record shows quite high percent occurrences of the Euphausiacea (96.8%) throughout five different whaling grounds worked out. There were no biassed trends ofthe regional occurrence in Euphausiacea, and fish food accounted only 3.2% amongall. This was really unexpected evidence from that supposed in advance to thecatch of whales came to an implementation (Table 3).
The quantity of stomach contents actually found in each animal was found to
be relatively abundant. Table 3 shows that 253 animals (55%) out of 459 wererepleted with food under various magnitudes. It must be noted that 70 animals
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

6(27.7%) out of 253 were found to be very abundantly (75%+100%) repleted withfood. To see the similar figures by each whaling ground, the highest was foundin the Coral Sea (40.0%) and/or southwestern Indian Ocean (36.7%) while thelowest was in the central South Pacific (22.4%) for the 1976/77 season. Thesefigures may suggest that there must be comparatively abundant distributions ofavailable food concentrations even in the so-called 'barren' tropical seas, the placeof far well outside from the proper feeding ground of baleen whales in the southernoceans.

Diel changes in the quantiry of stomach contents
It may be hard to believe that the baleen whale shows any local behavioral
changes in their feeding activity or behavioral pattern to an appreciable extent although some locally modulated changes are expected by the composition of available food species due to their own local characteristics in the diel migratory pattern. If the whale does not change essentially their behavioral pattern of feeding,then the diel variation of the quantity of stomach contents may suggest the dielvariation offeeding activity and/or its intensity.
c)

Fulness of st0<00ch

20

SW Indian OceanCl976/77)

N:I05

Empty

15

c:::::::J

0-25% ~

JI)

25-50% ~50-75%lllllllllllllil
75-100% Eastern Indian OceanU978/79)

Nd20

L_. ~~~~n~L.l.L....m.J
0 [k, [lm Dm
n ~ M..LJ.. - [l. [}A 0 -1051---1-Jf

r4

[km

....-iI~::1~._F[ _.....So-ut-h~Poc~lf~lc-Cl...i97~7/~73•)--'-"'N:Lll~4._..."""'--'--"'....,l...JIZ£"-l..lim._.LIZElllll...l~.._..EaS!...._-"""~Jm....ia.c:""--'
0 0 [b [l_ f1i J1Jm. ~ CL ___,,__ crmi rrOJAm.!]k ,n,. • .,.,.
_!

S~ea1C I_97-6/...i~7_,,'.,.L..-N ~ ..m"'PlllL--'-'_ _,__ _.___._ _ _ _-'no___,5 ,_f--'C'-o-ro_l

=
.....

South PaciflcCI976/77l

N:113

19

Local time of catch

Fig. 2. Change of stomach fulness by the local time of catch in five different whaling areas.

Figure 2 demonstrates the number of animals by the five different stomach conditions against local time when the animals were caught. Among the animals withfood of any magnitudes in their stomach, it is observed that th.e stomachs repleted
50% or more seems to occur poorly except very few examples. This may suggestthat the stomachs with food are represented chiefly by rather poorly repleted
animals. The occurrence of empty stomach predominated during the first halfof day, and seems to reduce toward evening. The empty stomach was foundSci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

7

largely in three examples; southwestern Indian Ocean (1976/77), equatorial eastern
Indian Ocean (1978/79) and the South Pacific (1977/78). In the Coral Sea region
the number of catch amounted only seven animals in all, and it is difficult to draw
any general trends offeeding activity. On the other hand, feeding condition in theSouth Pacific region for 1976/77 season showed very high percent occurrence of well
repleted animals (75.22%), while the rest ranged 44.7-52.6% (see also Table 1).
The die! changes in feeding activity can be observed over the regions in question.
In the animals from southwestern Indian Ocean the occurrence of well repleted stomachs was concentrated clearly in the first half of the day, and this region must be
noted of being different feeding conditions from the four others. There were nocatches after 1600 hours in this region. On the other hand, the animal with well
repleted stomachs in the eastern Indian Ocean, South Pacific and possibly in the
Coral Sea showed dispersed occurrence over the whole daytime but somewhat biassed

30.A---& Total

t'.'\

28

I'

26

0 - 0 S. Pacific (76/77)
x------x S. Pacific (77 /78),._ __ _., E. Indianl'r- -l:. SW Indian

.

\

24

\

22
20

r,k--~\\, It-'Vj

ro 18

-~

~ 16

'O 14

lf-4 ~·

0

z 12
10

\\

\

8
6

I
I

4
2

I

I
I

''

6

Fig. 3.

_,·/

x' /

J,_

I

7

8

9

10 11 12 13 14 15 16 17 18 19 20
Local time of catch

Diel variation in the number of animals with filled stomach.

in the afternoon toward evening, and a possible nocternal feeding may take place inthese sea regions. Although there observed quite unusual large number of animals in
the morning for the 1976/77 and the 1977 /78 seasons of the South Pacific, the feeding
activity of whales on the whole possibly follows to a definite trends. That is, despite a great variety in the die! feeding activity of whales by season and localities,
it is noteworthy that more intense feeding would take place twice a day to show abimodal changes, once in the early morning and then toward the evening (Fig. 3 ).
The more detailed figures relating feeding activity are given in appended tables(Appendix Tables I and II).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

8TABLE 4.

SYSTEMATIC LIST OF THE FOOD ORGANISMS
OF THE SOUTHERN BR YDE'S WHALES

Euphausiacea :Euphausia recurva Hansen
Euphausia diomedeae Ortmann
Euphausia sibogae Hansen
Pseudeuphausia latifrons (G. 0. Sars)
Thysanopoda tricuspidata Milne-Edwards
Thysanoessa gregaria G. 0. Sars
Pisces:Vinciguerria nimbaria (Jordan & Williams)
Auxis thazard (Lacepede)
M yctophiformes** unidentifiable larval forms
TABLE 5.

KIND OF FOOD ORGANISMS OF SOUTHERN BRYDE'S
WHALES BY THE SEASON AND CATCH AREAS

SeasonDate

Sea temp.
(oC)

1976/77

Oct. 24-25

28°

Oct. 30Nov. 5

200-23°Mar. 7-13

24.6°-26.6°

1977/78

Oct. 29Nov. 18

20.2°-23.4°

1978/79

Nov. 3Nov. 19

25 .8°-30. 3°

Approx.
location
9°49 1-10°17 1 sCoral Sea
157°291-157°561E
24°25 1-27°59 1 s
S. Pacific
l 77°1l1-l 78°34 1E
28°23 1-31°47 1s
SW IndianOcean
43°55 1-51°36 1E
21°15 1-29°24 1s
S. Pacific
179°45 1 E-l 70°58 1W
Sea area

E. IndianOcean

9°47 1-12°49 1 S
92°021-118°321E

Food species

Euphausia diomedeae
Euphausia recurva
Thysanoessa gregaria
Euphausia recurva
Hatchetfish*
Euphausia recurva
Thysanoessa gregaria
Gonostomatid fish**Euphausia diomedeae
Euphausia sibogae
Pseudeuphausia latifrons
Thysanopoda tricuspidata
Vinciguerria nimbaria
Auxis thazard
Myctophiformes* fouf!d only one specimen as a possible contaminant.
** probably V. nimbaria.

Kind offood organisms
There have been found comparatively poor compos1t10n of food species forthe southern Bryde's whales in pelagic waters (Kawamura, 1977). It is clear thatthe Bryde's whales feed mainly upon Euphausiacea and the shoaling fish or its larval forms, and epipelagic planktonic or micronektonic organisms other than eueuphausiids were much lesser extent (Table 4 ).
The result actually found was that hardly been expected until the catches ofBryde's whales were implemented. Among the Euphausiacea, there found three
species of the genus Euphausia (E. diomedeae, E. recurva and E. sibogae) and one species
belonging to the three different genera, i.e., Thysanopoda tricuspidata, Thysanoessa gred)

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

9garia, and Pseudeuphausia latifrons. T. gregaria must be considered tentative identification due to ill conditioned specimens by digestion. The geographical occurrence ofeach food species is given by the whaling grounds in Table 5. It is observed thatthe composition of food organisms is very monotonous over the first four whaling
grounds where E. diomedeae, E. recurva and/or T. gregaria predominated. Fish wasconsidered to be less important by any magnitudes. The equatorial eastern Indian Ocean, on the other hand, showed relatively diversed complexity to the another four cases in the composition of stomach contents. However, there foundonly P. latifrons as the principally important food species than three another species.
As for the gonostomatids, Vinciguerria nimbaria showed a mesa-scale importanceamong the whole member of food species. V. nimbaria has been found to be of greater importance as the food of skip jack, Katsuwonus pelamis in the tropical Pacific(Kubota and Kawamura, 1972).
TABLE 6. OCCURRENCE OF SPERM SAGS IN SIX EUPHAUSIIDSPECIES FED BY THE SOUTHERN BRYDE'S WHALES
Sperm sac present:
Both
Male+Female
E. diomedeae
E. diomedeae
E. recurva
E. recurva
E. recurva
T. gregaria
T. gregaria
E. sibogae
P. latifrons
T' da tricuspidata

3
6
2

Only
Male

AbsentFemale
I
6
28
29
3

2

Unknown

Whaling groundMale+Female
2
5
5
30
11
35

2
29

2
11
16
2
2
4
2

Coral Sea
E. Indian
S. Pacific (76/77)
SW Indian
S. Pacific (77 /78)
S. Pacific (76/77)
S. Pacific (77 /78)
E. Indian
E. Indian
E. Indian

The populations of six euphausiid species above mentioned are usually composed of both adult male and female in similar sex ratios though there were several
cases of slightly biassed sex ratios with more numerous in the number of male than
the female. Although the majority of T. gregaria was composed of adult forms ofboth sexes, there were a few cases that adolescent or juvenile forms occurred mixing with the adults. Some male and/or female individuals over several populations of above six euphausiid species carried a sperm sacs on the thelycum or ejaculatory duct but this strongly biassed to females (Table 6). E. diomedeae of theCoral Sea population carried the sperm sacs on both sexes, while it was only on
females from the equatorial eastern Indian Ocean. Similar trends were found in
T. gregaria but no sperm sacs were found in the South Pacific populations occurredin the 1976/77 season. Although, there found very occasional occurrence of carrying sperm sacs in P. latifrons, it may be reasonable to refer the species as having
no associations with mating at this time of the season viz. early to mid-November.
One of interests is that there were very close associations in the occurrence of posSci. Rep. Whales Res. Inst.,

No. 32, 1980

KAWAMURA

10

sible euphausiid eggs with P. latifrons. The appearance of the egg was observed
very similar to those of euphausiids. Therefore, it is reasonable to suppose that theegg might perhaps come from P. latifrons since it was the only species that possibly
lost sperm sacs from all individuals occurred. Thysanopoda tricuspidata also did notcarry sperm sacs but this species by no means occurred associating with any kindof planktonic eggs.
In summerizing the results concerning euphausiid food, it is noticed that bothE. recurva and T. gregaria covered geographically wider ranges and are consideredmost important food species in the central South Pacific while it was only E. recurva
in the southwestern Indian Ocean. In the equatorial eastern Indian Ocean, on
other hand, the principal dietary members turn to P. latifrons and E. sibogae. BothT' da tricuspidata and E. diomedeae occurred with much lesser extent.
TABLE 7. PREY ORGANISMS FOUND FROM SOME FISH SPECIES THATWERE FED BY THE BRYDE'S WHALES TAKEN IN THE EQUATORIAL
EASTERN INDIAN OCEAN DURING 1978/79 SEASONFish species

Body length(mm)

Au.x:is thazard (Frigate
mackerel)

215

Vinciguerria nimbaria

38-50

Location

Date

Food items

10"14 1 s

Nov. 9, 1978

Nov. 15-17, 1978

Candacia pachydactyla
Euchaeta marina?
Others*
Copepods**
Fish larva
Euphausiid(P. latifrons) -egg?

Nov. 15, 1978

Copepods**

112°12 1 E
11°00 1 s
97°121 E
11°13 1 s
95°26 1 E

11°15 1 s
95°32 1 E

M yctophiformes

24-25

11°16 1 s
95°28 1 E
11°52 1 s
94°12 1 E
11°16 1 s
97°34 1 E

* Decapoda-megalopa, large cheliped like appendages, Amphipoda-Hyperiidae, Lucifer? Cavolinia sp.
Bivalvia larvae, and unidentifiable crustaceans due to heavy digestion.
** unidentifiable.

As for the fish diet there found three kind of shoaling fish species: the Myctophiformes, gonostomatids (Vinciguerria nimbaria), and possibly contaminated one
specimen of frigate mackerel (Auxis thazard). Among these fish diet only the gonostomatid species, V. nimbaria was actually formed the diet of the southern Bryde's
whales especially in the equatorial eastern Indian Ocean. The unidentifiable larval
forms of fish belonging to the Myctophiformes was also preyed upon the animals
but by far the lesser magnitudes than V. nimbaria. In general the occurrence offish diet is very local phenomenon limited spacially in small area. Althouth the
Myctophiformes species was found only in one stomach, and V. nimbaria in five stomachs in the 1978/79 catches, they occurred in the state of solely monospecific cornSci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

11

position except one mixed example with E. diomedeae.
The prey organisms found from those above mentioned fishes were examinedin order to compare them with the stomach contents of whales. Both frigate mackerel and the Myctophiformes were very young forms, while V. nimbaria was adult.
Although the taxonomical details of prey organisms from these fish species are stillinsufficient, Table 7 demonstrates that the species composition of prey organisms
in the gut from those fish species are very variable. The frigate mackerel ate atleast several adult males of Candacia pachydactyla, Euchaeta marina (?) and many unidentifiable copepod species, Decapoda, Amphipoda, and very young Thecosomata
of possibly belongs to Cavolinia sp. It is noteworthy that not withstanding the factof greatly diversified prey items, there found to lack euphausiid species that were themain diet of the Bryde's whales. This, however, seems to be confirmed by further
TABLE 8.

NUMBER OF STOMACHS BY THE KIND OF FOOD ORGANISMS
1977/78

1976/77

1978/79---

S. Pacific Coral Sea SW Indian
E. diomedeae
T. gregaria
Euphausia sp. *E. recurva+ T. gregaria
T. gregaria+E. recurva
E. recurva
E. sibogae
P. latifrons
P. latifrons +E. diomedeae
T' da tricuspidata
Euphausia sp.**
E. diomedeae + V. nimbaria
Fish larva***+E. diomedeae
V. nimbaria

S. Pacific

5

38

7
29
2
2

11
38
8
11
9
109
7
29
2
2

4

4

6

10
7
8

28

51****Total

E. Indian3820

Gonostomatid fish
* Probably E. recurva.
** Probably E. sibogae.
*** Larval forms of Myctophiformes.
**** Mixture with one individual of hatchet fish is included.

examinations since micronektonic fish migrants in the tropical Pacific are known tofeed euphausiids by a magnitude accounting for 8% of total food ingested (Roger,
1973a). Even so the completely different gut contents of preyed fishes found fromthe whale stomachs suggest that these fish species were not associated with the occurrence of food euphausiids. It may be considered that those micronektonic fishes may linked with another branched off foodchain systems which are perhaps different one from the prey- predator relationships between Bryde's whales and euphausiids.

e) Composition of stomach contents
The composition of stomach contents from the collected samples is given in
Sci. Rep. Whales Res. Inst.,

No. 32, 1980

KAWAMURA

12

Table 8 by separating the' catch area and the season. In order to show the characteristics of the composition of stomach contents a matrix was constructed (Fig. 4 ).
Although a considerable diversity in the composition of forage was observed in general, it may be noticed that the principal food items were comprised of four major
euphausiid species; Euphausia diomedeae, E. recurva, Pseudoeuphausia latifrons, and Thysanoessa gregaria. Both South Pacific for the 1976/77 season and southwestern Indian oceans were represented largely by E. recurva, where this species accounted
59.4% and 98.1 % respectively in number of the stomach. Different from the previous season, however, T. gregaria occurred in addition to E. recurva as major food
Minor components

Food species

2

I

4

3

5

7

6

I

3

1)3

T, gregariaI2
5

P. latifrons

6

T. tricusp!data

Q)

c

0
o_

E
0

u

20 8

3

g I Jn ?O

7

4 E. sibogae..,c"''-----

51

2 E. recurva

29

I

2
I

L

0
·3 7 Euphausia sp,•

T

"'

I

8 Euphausla sP. ••Key to the nun1erals
in sauare

9 V. nimbarla
10

Gonostomatids

11

Myctophi formes

10

I

5

E. di omedeae

9

3

6

L >od<o"Coral Sea
I

4

~OW""'°"__l_s. Pacifics. Pacific( 1976/77)( 1977 /78)

• Probably E. recurva•• Probably E. sibogae

Fig. 4. Composition matrix for the 234 stomach analysis in the southern Bryde's
whales. Numerals in the square denote the number of stomachs by the five different whaling areas.

species by 50% of occurrence in the South Pacific for the 1977 /78 season. Although
the number of whale catches in the Coral Sea were seven in all, there occurred only
E. diomedeae. In the equatorial eastern Indian Ocean P. latifrons occurred in great
numbers, where this species accounted for 58.5% among all. E. recurva did notoccur in this locality but E. diomedeae and E. sibo,£;ae accounted for 11.3% and 13.2%
respectively. The latter two species can be refered to as a meso- scale importanceas the whales food. As it is noticed in Fig. 4 one of the characteristics in the equatorial eastern Indian Ocean may be found in the diversity of species composition
when it is compared with the case in four another whaling areas. It must be noted
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

13

that both E. sibogae and T' da tricuspidata by no means occurred under the mixed
state in composition with another kind of food species, while E. diomedeae, E. recurva, P. latifrons and T. gregaria, the principal food items of the southern Bryde's
whales in pelagic waters, occurred at times by mixture with one of each other. The
stomach contents composed of the Euphausiacea seem to very similar composition
over the different four whaling ground occupied through the 1976/77-1977 /78 seasons
while they changed notably to different food species in the equatorial eastern Indian
Ocean. Except the case in T. gregaria and E. recurva, there were very few stomachs
that were composed of mixture by more than two food species. Although there
were several instances scattered at far from the diagonal line which indicates a single species composition, the most stomachs were found to be characteristically composed of mono-specific composition, that is, 210 (89.7%) stomachs out of 234 foodcontained stomachs were comprised of only one food species. The animals in theSouth Pacific ground for both the 1976/77 and 1977 /78 seasons fed same euphausiid species and their mixture. It can be said that the general feature of the foodcomposition was very simple and the fish was of minor importance in so far as thegiven localities in pelagic waters.
While laboratory examination of the stomach contents under the microscope,
it was noticed that there were difference between each component species in theirfreshness and/or the magnitude of damages among the preserved materials of mixed composition with two or more kind of species. This may suggest a possible timelag due to the difference in feeding time by each component species. The whalemight have fed upon them from one to another, each of which might have hadformed aggregations independently with a little spacing over the spacially small
scaled area.

f)

Distribution offood species
Figures 5-6 demonstrate the horizontal distribution of food orgamsms by
species over the five whaling areas. The plot in the Fig. 5 represents all position
where positive occurrence of each food species was recorded. When the stomach
was composed of two species in mixed state, they were plotted separately by eachspecies elsewhere in the chart.
In the Coral Sea there found only five stomachs of containing E. diomedeae.
The South Pacific areas were visited twice during two successive seasons as noted in
the figure. Each whaling area is located at almost same sea region with a little
overlappings, but there were no notable differences in the catch periods and sea
temperature in these two seasons (see Fig. 1 and Table 4).
Since the catch of whales in the Coral Sea took place in a locally biassed area,
the occurrence of E. diomedeae was also confined to spacially small area. The
central South Pacific areas, on the other hand, covered over the wide latitudinalor longitudinal ranges of magnitudes expanding for several degrees. Both E. recurva and T. gregaria occurred over the whole geographical ranges but somewhat
dispersed distributions in the latter species. E. recurva for the 1976/77 season fairly well concentrated focally where the species occurred approximately within a laSci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

14

20'"' E. sibogae

40'• E. diomedeaeo E. recurva+ P. latifrons
b. T. tricuspidata• T. gregaria<> FishFig. 5.

24'

27'

0
0

Distribution of euphausiids and fish that were fed by the southern Bryde's whales.

s20'.---~~~~--.~~~-r---,-~~~~~~~

S. AFRICA

E. recurva~

30'

Southwestern Indian Ocean

1976/77
40'
S T. gregaria

-J-

28'
29'
50'

a....

30' :~·

Fig. 6.

·::

31' 'ri

32'
44'

60' 20'

...,

30'

46'

40'

50'

48'

50'

52'E

60'

E

Distribution of euphausiids that were fed by the southern Bryde's whales.

titudinal or longitudinal square by one-degree. Similar local concentrations wereagain observed in the 1977/78 season but lesser magnitude. It is, however, hard
to know whether or not the horizontal distribution of E. recurva and T. gregaria wasdifferent to any appreciable magnitudes. Very similar locally biassed concentrations of food euphausiids are also observed in the southwestern Indian Ocean but
the spacial expand of the whaling area was relatively larger than the formers.
In the equatorial eastern Indian Ocean the food species distributed with conSci. Rep. Whales Res. Inst.,
No. 32, 1980

15

FOOD OF BRYDE'S WHALES

siderable geographical differences by each species. P. latifrons was the most dominant food species among three others, and occurred more frequently in the eastern
half of this whaling area. Both P. latifrons and E. sibogae showed a possible very
closer associations with each other in their occurrence. Although very occasionalin frequency occurrence, E. diomedeae did not show such characteristic trends as
the former two species but somewhat closer associations with the gonostomatid
fish, V. nimbaria in the western area. T' da tricuspidata occurred at only two positions and hardly be known its distributional characteristics. There was the space
where the food organisms distributed very sparcely in the midst of the eastern Indian Ocean area. Although the reason why food organisms distributed so sparcely is unknown at present, the region well coincides with the area where distinct discontinuity of euphausiid distributions has been demonstrated (Ponomareva, 1972).
S Southwestern Indian Ocean
2 8 ',---,---,-,---,--,-~--,-----,---,S
South Pacific (1977 /78)
21 '.-----.--.---,---,-~~--.--.---,-~~

29'

22'

g':{;go

00

23'

30'

.i ::·

31°
32'

0.

24'

50'

25'
52'E 26'(1976/77)
So"th
Poomo

28'

'o

~~~_...,._~~-~~~~

s

44'

46'

"1 ~
26

I

24'

25

0

·i~:"::
~
••

··;.:

48'

27'
•

0

•

0

o •

12'

•

·.·
~-

•

~~o.

98'

Oo

0

Eastern Indian Ocean~~.

0g o•~\ce
00

0
0
0

00

96'

og

0

0

0
0

00~~

0

o••
0

13'
94'

0

: \=: : •

•

•

·.

OpP

0

27'
o
28'
..
176' 178'E

11 °

l, o

0
• 8.
29'
:?o 0 °
30°'----'--'--'---'-.1---'----'--'--'---'--'-'
178' E 180' 178' 176' 174' 172'W

0

10°

o

•·:•A>:

100'

102'

104' 106'108' 110'

8o

0

~

•

0.
• 0

o~•

112'

oi;•:
114' 116° 118'E

Fig. 7. Catch distribution of Bryde's whales during the seasons of 1976/77-1978/79.
Filled and open circles denote the animal of filled and empty stomach respectivelly.

To summerize the overall distribution characteristics of the food species
throughout the five different whaling areas, it is obvious that the main concentration area of food organisms and whales distributed unevenly with local biass
over the regions worked out. From this viewpoints it may be observed that theconcentration of whales occurred at very spacially small localized areas where the
distribution of aggregated food organisms showed quite biassed occurrences. These
therefore, can be confirmed that 'the animals with filled stomach concentrated in
the way above mentioned while those with empty stomach having been possibly
in search of food were found to show relatively scattered distribution over the whole
whaling areas (see Fig. 7). This evidence may suggest that the movement of whales
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

16

KAWAMURA

in the tropical and/or subtropical seas is significantly related to the presence of available foods. Where abundant food distribution is exhibited, movement of whales
may become stationary for the time being.
DISCUSSION

Several past catch records of the Bryde's whales in the southern hemisphere arecompletely confined to the catches by the land based operations. This may represent very locally limited feeding conditions for the whales occurring in coastal tooffshore regions since locally characteristic environmental conditions in near shore
waters may determine the faunal distribution-the occurrence of endemic species
including planktonic organisms.
There have been reported a several number of such informations as that camefrom the coastal whaling. In regard to food and/or feeding habits of the Bryde's
whales in the southern hemisphere, Symons (1955) described only pilchards foundfrom the Saldanha Bay animals. Examining Donkergat animals, South Africa,
Olsen (1913) more earlier reported that the Bryde's whales feed upon 'fish' and hefound but one occasion of the remains of euphausiid crustaceans. Best (1960)
summerized some of those earlier data and reported that the catches of Bryde's
whales in the southern hemisphere are largely took place around the South African
coast, but there were also catch records of lesser extent in Western Australia, North
Island of New Zealand, and northern Chile. The Saldanha Bay animals were
found to feed upon pilchard (Sardinops occellata) and anchovy (Engraulis japonicus)(Best, 1960), but the latter was corrected to be E. capensis in the later study. Morelater, Best (1967) reported that the majority of Bryde's whales of visiting Cape Province region, South Africa feed upon both shoaling fish such as pilchard (Sardinops
occellata) and anchovy (Engraulis capensis), and euphausiids, Euphausia lucens. Bannister and Baker (1967) also reported but one instance of E. recurva as the food of
Bryde's whales off Durban. Best (1977, Table 5), however, gave more complete
sets of dietary habits, where he reported the following food items by identifying
both inshore and offshore forms of the Bryde's whales each of which demonstrates
very characteristic food habits: The inshore form chiefly feeds upon shoaling fish
members, Engraulis capensis, Trachurus trachurus (jack mackerel), and Sardinops occellata, while the offshore form feeds largely upon the Euphausiacea such as Euphausia
lucens, E. recurva, Nyctiphanes capensis and Thysanoessa gregaria along with some pelagic fish species such as Maurolicus muelleri, Lestidium sp., Scomberesox saurus and Scombrid sp. He (Best, 1977) also found cephalopods, Lycoteuthis diadema, as the first record as whales food from the same locality. In northern waters off Point Cloates,
Western Australia, Euphausia hemigibba and Pseudeuphausia latifrons were found fromthe humpback whales (Dall and Dunstan, 1957), and these are considered to be apossible Bryde's whales food in that locality. In the southern waters off Western
Australia, the Bryde's whales are known to feed upon Engraulis australis and/or
young mackerel, Pneumatophorus australiasicus (Chittleborough, 1959), while itchanges to mugilid fish called 'mullet' and crustaceans at Great Barrier Island in
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

17

the Hauraki Gulf, New Zealand (Gaskin, 1976). Aguayo (1965) examined first
the South American 'sei' whale at Iquique, northern Chile and found the animal
was identical to the so-called Bryde's whales but failed to show its food items except 'fluid' from the lst to 2nd stomachs.
All that the food items of the southern Bryde's whales having been known todate strongly suggests the animal preferable feeds upon shoaling fish of mostly commercial importance instead of planktonic organisms during their stay in the coastal or near shore waters. On the population and movements of the Bryde's whalesin the New Zealand waters, Gaskin (1977) states that " ... it is largely confinedto the area between North Cape and East Cape on the eastern side of the North
Island, and migratory only in the sense that groups of these whales appear tofollow local movements of pelagic fish schools". However, the distinct planktivorous food habits as demonstrated by the offshore form of the Bryde's whales'in
the South African waters where the animal feeds largely upon euphausiids (Best,
1977) are noteworthy. The animal of offshore form is characteristic for having ashort but relatively broader width of baleen plates while the inshore form is furnished with slender, a more sei whale-like baleen plates. Form the morphological orfunctional point of view concerning baleen plates (e.g. Nemoto, 1970), the offshore
form seems to be more adapted to swallowing type of feeding which seems to be more
effective to eat fish.
Although the baleen plates of the southern pelagic species caught by special
permit have not been studied to date the whole filter area formed by the baleenseries in the South Pacific animals caught during 1976/77 season was significantly
smaller than that found in the pelagic North Pacific animals (Kawamura andSatake, 1976; Kawamura, 1978a). This may suggest the South Pacific, Coral Sea,and possibly the Indian Ocean animals to be an identical types of baleen plates tothe offshore form of the South African waters. According to Kawamura and Satake(1976) the North Pacific Bryde's whales show two different types of baleen plates
but each of which is similar to the forms found in the South African animals although there were considerable variations from one to the another. The baleen
plates of Bryde's whales being caught in the coastal region in Japan showed generally a stronger similarity to those of offshore form while the animals in the pelagic
waters were of the inshore form. The 88.9% of totaling 109 North Pacific animals
from pelagic waters feed the Euphausiacea while 11.1 % were the fish (N emoto and
Kawamura, 1977). On the other hand, the animal in the coastal waters around
Japan feeds on variable food items by the localities but mainly focussed on both
shoaling fish such as anchovy (Engraulis japonicus), Trachurus japonicus, Afyctophum
asperum and euphausiids (E. similis, E. recurva and possibly E.pacifica) (Nemoto, 1959).
In the eastern North Pacific off Baja California, the Bryde's are reported to feed
upon the red crab, Pleuroncodes planipes and anchovy, Engraulis mordax (Rice, 1977).
These above mentioned evidences may suggest that the Bryde's whales of occurring in the coastal waters of both hemispheres are considered to be a distinct
ichtyophagous animals among all of the balaenopterid whales, i.e., the Bryde's
whale seems to feed upon whatever the organisms of greater availability or encountSci. Rep. Whales Res. Inst.,
No. 32, 1980

18

KAWAMURA

ered frequently in the surrounding environments. In this connection such the morphological characteristics of baleen plates as found in both allopatric forms by nomeans determine the kind of food species, and these perhaps mean the lesser ecological functions in the food preference throughout the whole population of the Bryde's
whales. An instance that ichtyophagous inshore form of Bryde's whale feeds aneuphausiid, Nyctiphanes capensis in the South African waters (Best, 1977) suggests
the animal preys upon simply due to the abundant distribution of N. capensis in the
neritic waters (Brinton and Gopalakrishnan, 1973).
As observed in this study it was only the Euphausiacea that was taken largelyby the Bryde's whales in the pelagic waters as the main dietary organisms of the
Bryde's whales over the central South Pacific, Coral Sea, southwest and equatorial eastern Indian oceans. In general the food of tunas and skip jacks occurringin the Pacific equatorial regions is composed of young or larval forms of many kindof fish, cephalopods and planktonic crustaceans other than euphausiids which areof minor importance, although the larval fish feed largely on zooplankters (Shirota,
1975 ). These might resulted from the difference of feeding types of animals as thefilterer and/or the attacker, but also came from the difference of ambient biomass ofeach prey organism and diel feeding activity of predators (Roger, 1973b). Even
young fish of various kinds in the tropical pelagic waters by no means forms such
school or aggregations of enormous biomass as usually found in euphausiid swarms.
The fish usually shows more dispersed distribution than the euphausiids but may
give fairly larger biomass by the individual basis (Nemoto and Kawamura, 1977).
This may be more beneficial for the attack-feeder than for the filter-feeder. The
baleen whales cannot but feed upon euphausian swarms, which may occur under
the strongly and locally biassed conditions. Although some copepods such as
Clausocalanus arcuicornis seems to occur numerously in the Central Pacific (Chiba
and Hirakawa, 1972), and actually both C. arcuicornis and C. laticeps have been foundas the food ofsei whales (Best, 1967; Kawamura, 1974). Even so, there seems little
possibility of occurring any kind of prey organisms except euphausiids for thebaleen whales in the pelagic region of the tropical to subtropical waters where noplanktivotous and school forming fish stocks hardly be exist. The possible total
amount of available euphausiid food per head of animals in the tropical sea regionin terms of occurrence freguency of animals was 44-7 5 % (Table 1), and this ishardly comparable with that of 70-90% found in the feeding grounds in boreal orcolder seas (e.g. Kawamura, 1978b).
The concentration or the feeding of Bryde's whales took place was spotted insome local area while the euphausiid species in general distribute widely over thewhole South Pacific and Indian oceans in question (Brinton, 1962; Brinton and
Gopalakrishnan, 1973). To see the distinct mono-specific composition of stomach
contens, it is clear that the euphausiid species actually fed by the Bryde's whales
are considered to be the swarm forming species that distribute numerously in theepipelagic and/or meso-pelagic waters.
According to Brinton (1962), E. recurva shows biantitropical distribution in
the Pacific but somewhat scarce in the southern hemisphere. The day-night depth
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S. WHALES

19

distribution of this species is biassed in the upper 100 m during the night but it isbelow 140-700 m during the day, and he (Brinton, 1962) found only daytime aggregations of furcilia larvae below 140 m. T. gregaria, one of another importantfood species of the Bryde's whales in the South Pacific may occur between 25-300 m
during the night but it is below 500 m during the day. E. diomedeae, the only foodspecies both in the Coral Sea and equatorial eastern Indian Ocean is found 10140 m during the night but this species goes down to deep far below during the day.
The rest euphausiid species fed by the whale may demonstrate a similar pattern ofdiel depth distribution or the species known as the lesser migrant such as P. latifrons(Brinton, 1962). The Brinton's findings suggest a scarcity of the whales food during
the day. The diel changes in stomach conditions, however, strongly suggest thata possible daytime feeding of whales actually took place in all five different whaling
areas (see Fig. 2). This may lead to a consideration that those food euphausiid
species may come to or be stationary close to the surface layers even the daytime atleast when they aggregate to form the patchy swarms. However, it is still unknown
that the aggregation of euphausiid species is related to their feeding, since active
feeding intensity in the shallower layer in E. diomedeae and T' da tricuapidata is concentrated during the night later than 20 hrs (Roger, 1973c). The occurrence of
sperm sacs in female or in both sexes of those species might have possibly related
to their aggregations at such a shallower layer as to be fed by the whales during the
austral summer. Even so, it is curious that any species of the genera Stylocheiron and
Nematoscelis were not fed by the whales while only these genera having been known
to occur abundantly during the day in the tropical South Pacific Ocean (Roger,
1973d), and actually ichtyofauna of Gempylidae, Paralepididae, and Bramidae
feed largely upon Stylocheiron and Nematoscelis (Roger, 1973b). The catches in thesouthwestern Indian Ocean represents only the materials collected in the austral
autumn while other four collection areas are early summer. The food species foundin each local and seasonal set of the catches and the magnitude of stomach fulness,were not different each other. This may lead to a consideration that there might
be very few seasonal changes in the availability of food euphausiids in terms of both
quality and quantity. The abundance of euphausiids in a magnitudes of ordinalbiomass by no means of any importance for the baleen whales but surface swarms
of several hundreds to thousnads times of biomass per unit volume of water must
be expected over the study areas as the similar case found in the copepod food(Kawamura, 1974).
The complicated occurrence of euphausiid food in the equatorical eastern
Indian Ocean may largely be due to the characteristics of zoogeography in the
Inda-Pacific regions. The eastern Indian Ocean ground was situated within theranges of the South Equatorial Current systems to which strong westerly currentof Pacific origin may flow via the Arafura, Banda and Java seas (Wyrtki, 1973).
Although the distribution of zooplankton biomass in this region varies with seasons
under the influence of southwestern or northeastern monsoon, the whaling area inthe eastern Indian Ocean was corresponded to relatively larger biomassed planktonrich region especially during October-November (Rao, 1973). Studying the mysids
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

20

KAWAMURA

and euphausiids in the eastern Indian Ocean, Taniguchi (1974) actually found afairely complicated faunal composition in the waters south of Java Island and pointed out that the diversity of species composition in the area is mainly due to the inflowof the Banda Sea waters. Among the euphausiids species that showed the mostfrequent occurrence in the region as reported by Taniguchi (1974), three food species for the Bryde's whales, T'da tricuspidata, P. latifrons and E. diomedeae were included. Only E. sibogae is reported to be of minor importance by lesser magnitudes ofoccurrence (Taniguchi, 1974). The lesser occurrence of the genus Euphausia asfood of Bryed's whales in the eastern Indian Ocean agrees well to the findings by
Taniguchi (1974), and this along with the ocean current systems may further related to the faunistic characters of the Euphausiacea in the Sulu Sea region (Ponomareva, 1976). Brinton and Gopalakrishnan (1973) found the abundant distributionof P. latifrons, that was the commonest food species in the equatorial eastern Indian Ocean during November-March and noted the region as "a typical parts ofthe distribution". Ponomareva (1972) also showed the eastern equatorial Indian
Ocean including southern waters off Java Islands as the high biomassed and ecologically interesting region from a viewpoint of food chains. Brinton and Gopalakrishnan (1973) states "Essentially a neritic euphausiid, P. latifrons was nevertheless caught sporadiacally throughout the oceanic part of the tropical zone, but usually near islands". The frequencies of euphausiid occurrence as the food of Bryde's
whales in the Indian Ocean was very similar to the general geographical abundance. of each euphausiid species.
Despite the very much diversified communities, species composition and distribution of euphausiids in the tropical to temperate Pacific and Indian oceans(Mauchline and Fisher, 1969), there seems to be very little number of species thatare actually available to the baleen whales as their primaly diet in the pelagic partof those warmer sea regions. The former studies on the diet of baleen whales
made it clear that the food organisms must be the species undoubtedly aggregate
densely to form the patchiness (Nemoto, 1963; Kawamura, 1974, 1978c; Brodie
et al., 1978). From the obvious mono-specific composition of stomach contents,
E. diomedeae, E. recurva, E. sibogae, P. latifrons, and T' da tricuspidata may be refered
to as the distinct swarm-forming species. Among these members, at least T' datricuspidata, P. latifrons and E. diomedeae have been known to be the omnivorous and/or detritus feeders (Ponomareva et al., 1962; Roger, l 973c, 1978; Mauchline andFisher, 1969). The pelagic food relationships, Bryde's whale vs euphausiids, copepods vs young fish and then, young fish vs larger fish are the subject of biologicalinterests in connection with comparing those in the coastal waters and with the casein another whale species. Both biological and ecological knowledge on the euphausiid swarms along with their food habits would be one of the key subjects inthe steps of studying tropical marine ecosystems since only the genera Stylocheiron
and Nematoscelis have been known as possible swarm-forming food organisms during
the light hours of the day in the tropical Pacific (Roger, l 973e,f).

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES21

REFERENCES
AGUAYO L., A. 1965. Bryde's whale in the Southeast Pacific. Norsk Hvalfangst-Tid., 54 (7): 141-148.
BANNISTER, J. L. and A. de C. BAKER, 1967. Observations on food and feeding of baleen whales at Durban.
Norsk Hvalfangst-Tid., 56 (4): 78-82.
BEST, P. B. 1960. Further information on Bryde's whale (Balaenoptera edeni Anderson) from Saldanha Bay,South Africa. Norsk Hvalfangst-Tid., 49 (5): 201-215.
BEST, P. B. 1967. Distribution and feeding habits of baleen whales off the Cape Province. Invest/ Rep. Div.
Sea Fish. S. Afr., 57: 1-44.
BEsT, P. B. 1977. Two allopatric forms of Bryde's whale off South Africa. Rep. int. Whal. Commn. (Special
Issue 1): 10-38.
BRINTON, E. 1962. The distribution of Pacific euphausiids. Bull. Scripps Instn. Oceanogr., Univ. Calif., 8 (2):51-270.
BRINTON, E. and K. GoPALAKRISHNAN, 1973. The distribution of Indian Ocean euphausiids. In: B.
Zeitzschel (ed.) The Biology of the Indian Ocean., Springer-Verlag Berlin, Heidelberg, New York: 357382.
BRODIE, P. F., D. D. SAMEOTO and R. W. SHELDON, 1978. Population densities of euphausiids off Nova
Scotia as indicated by net samples, whale stomach contents, and sonar. Limnol. Oceanogr., 23 (6): 12641267.
CHIBA, T. and K. HIRAKAWA, 1972. Classification and communities of the zooplankton in the South-Western Pacific Ocean, with special reference to copepods. j. Shimonoseki Univ. Fish., 21 (1): 67-80.
CHITTLEBOROUGH, R. G. 1959. Balaenoptera brydei Olsen on the west coast of Australia. Norsk HvalfangstTid., 48 (2): 62-65.
DALL, W. and D. DUNSTAN, 1957. Euphausia superba Dana from a humpback whale, Megaptera nodosa (Bonnaterre), caught off southern Queensland. Norsk Hvalfangst-Tid., 46 (1): 6-12.
GAMBELL, R., P. B. BEST, and D. W. RrcE, 1974. Report on the international Indian Ocean whale marking cruise, 24 November 1973-3 February 1974. IWC/SC/26/37.
GASKIN, D. E. 1972. Whales Dolphins and Seals: with special reference to the New Zealand region. Heinemann Educational Books Ltd, and St. Martin's Press, Auckland, London and New York. 200 p.
GASKIN, D. E. 1976. The evolution, zoogeography and ecology of cetacea. Oceanogr. Mar. Biol. Ann. Rev.,
14: 247-346.
GASKIN, D. E. 1977. Sei and Bryde's whales in waters around New Zealand. Rep. int. Whal. Commn.
(Special Issue 1): 50-52.
KAWAMURA, A. 1974. Food and feeding ecology in the southern sei whale. Sci. Rep. Whales Res. Inst., 26:
25-144.
KAWAMURA, A. 1975. A consideration on an available source of energy and its cost for locomotion in fin
whales with special reference to the seasonal migrations. Sci. Rep. Whales Res. Inst., 27: 61-79.
KAWAMURA, A. 1977. On the food of Bryde's whales caught in the South Pacific and Indian oceans. Sci.
Rep. Whales Res. Inst., 29: 49-58.
KAWAMURA, A. 1978a. On the baleen filter area in the South Pacific Bryde's whales. Sci. Rep. Whales Res.
Inst., 30: 291-300.
KAWAMURA, A. 1978b.- An interim consideration on a possible inter-specific relation in southern baleen
whales from the viewpoint of their food habits. Rep. int. Whal. Commn. 28: 411-419.
KAWAMURA, A. 1978c. [On an extremely biassed distribution of zooplankton-an estimation of spacialscale of bias]. Marine Sciences Monthly, JO (llJ: 877-888. (in Japanese).
KAWAMURA, A. and Y. SATAKE, 1976. Preliminary report on the geographical distribution of the Bryde's
whale in the North Pacific with special reference to the structure of filtering apparatus. Sci. Rep. Whales
Res. Inst., 28: 1-35.
KUBOTA, T. and A. KAWAMURA, 1972. [Notes on two species of Vinciguerria eaten by sei whale, Balaenoptera
borealis in Antarctic Ocean and skip jack, Katsuwonus pelamis, in tropical Pacific Ocean]. Geiken-Tsushin, 250: 43-47. (in Japanese).
MASAKI, Y. 1979. [Whale sighting and tagging investigations in the lower latitudes of the Pacific Ocean
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

22

KAWAMURA

during the winter of 1978]. Geiken-Tsushin, 324: 15-24. (in Japanese).
MAUCHLINE, J. and L. R. FISHER, 1969. The Biology of Euphausiids. Advances in Marine Biology, Vol. 7,
Academic Press, London and New York, 454 p.
NEMoTo, T. 1959. Food of baleen whales with reference to whale movements. Sci. Rep. Whales Res. Inst.,
14: 149-290.
NEMOTO, T. 1963. Some aspects of the distribution of Calanus cristatus and C. plumchrus in the Bering and its
neighbouring waters, with reference to the feeding of baleen whales. Sci. Rep. Whales Res. Inst., 17: 157170.
NEMOTO, T. 1970. Feeding pattern of baleen whales in the ocean. In: J. H. Steels (ed.), Marine Food Chains,
Univ. Calif. Press, Berkeley and Los Angeles, pp. 241-252.
NEMOTO, T. and A. KAWAMURA, 1977. Characteristics of food habits and distribution of baleen whales withspecial reference to the abundance of North Pacific sei and Bryde's whales. Rep. int. Whal. Commn.
(Special Issue 1): 80-87.
0HSUMI, S. 1978. Provisional report on the Bryde's whales caught under special permit in the southernhemisphere. Rep. int. Whal. Commn. 28: 281-287.
0HSUMI, S. 1979. Population study of the Bryde's whale in the southern hemisphere under scientific permit
in three seasons, 1976/77-1978/79. IWC/SC/31/Doc. London, June, 1979.
OLSEN, 0. 1913. On the external characters and biology ofBryde's whale (Balenojitera brydei), a new rorqualfrom the coast of South Africa. Proc. ::.ool. soc. Lond.: 1073-1090.
OMURA, H. and T. NEMOTo, 1955. Sei whales in the adjacent waters of Japan. III. Relation between
movement and water temperature of the sea. Sci. Rep. Whales Res. Inst., 10: 79-87.
PoNOMAREVA, L. A. 1972. Quantitative distribution of euphausiids in the Indian Ocean. Okeanologia,
12 (4): 689-694.
PoNOMAREVA, L. A. 1976. Euphausiids of the Sulu Sea and adjacent waters. Oceanologv, 16 (5): 514-516.
(Engl. ed., 1977).
PoNOMAREVA, L. A., A. G. NAuMov, and V. V. ZERNOVA, 1962. The feeding of some euphausiids in the
Indian Ocean. Trudy Inst. Okeanol., 58: 163-166.
RAo, T.S.S. 1973. Zooplankton studies in the Indian Ocean. In: B. Zeitzschel (ed.), The Biologv of the
Indian Ocean. Springer-Verlag Berlin, Heidelberg, New York: 243-255.
RICE, D. W. 1977. Synopsis of biological data on the sei whale and Bryde's whale in the eastern North
Pacific. Rep. int. Whal. Commn. (Special Issue 1): 92-97.
RoGER, C. 1973a. Investigations on the trophic position of a group of pelagic organisms (Euphausiacea).
IV. Relationships with other micronektonic elements. Mar. Bio!., 19: 54-60.
ROGER, C. 1973b. Ditto. V. Relationships with tuna. Mar. Biol., 19: 61-65.
ROGER, C. 1973c. Ditto. II. Trophic behaviour. Mar. Biol., 18: 317-320.
RoGER, C. 1973c. Ditto. I. Trophic levels of species. Mar. Biol. 18: 312-316.
ROGER, C. 1973e. Ditto. III. The group as a food source. Mar. Biol., 18: 321-326.
ROGER, C. 1973f. Ditto. VI. Conclusions on the role of euphausiids in the food webs of the inter-tropical
Pacific Ocean. Mar. Biol., 19: 66--68.
ROGER, C. 1978. Bioecological sheets on tropical Pacific Euphausiids. Initiations-Documentations Techniques,No. 36, ORSTOM, Paris, 81 p.
SHIROTA, A, 1975. [Fresh-Marine organism as living feed for Fisheries]. Koseisha-Koseikaku, Tokyo, 514 p.
(in Japanese).
SYMONS, H. W. 1955. Do Bryde's whales migrate to the Antarctic? Norsk Hvalfangst-Tid., 44 (2): 84-87.
TANIGUCHI, A. 1974. Mysids and euphausids in the eastern Indian Ocean with particular reference to invasion of species from the Banda Sea. J. mar. biol. Ass. India, 16 (2): 349-357.
WADA, S. 1975. [Whale tagging investigations in the southwestern Pacific]. Geiken Tsushin, 284: 27-34.
(in Japanese).
WYRTKI, K. 1973. Physical oceanography of the Indian Ocean. In: B. Zeitzschel (ed.) The Biolog;• of the
Indian Ocean., Springer-Verlag Berlin, Heidelberg, New York: 18-36.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

FOOD OF BRYDE'S WHALES

23

APPENDIX TABLE I. NUMBER OF ANIMALS BY THE QUANTITY
OF STOMACH CONTENTS AGAINST LOCAL CATCH TIME
CORAL SEA (1976/77)

c0.
s
i:Ll

..i::

B
(';j
u

......
0

.§"'
OJu
0

....:I

Quantityless than (%)
25

50 75 100

Total
with
food

c0.
s
i:Ll

I

4
4
4
I
2

5
6
7
8
9
JO
II
12
13
14
15
16
17
18

SOUTHWEST INDIAN
OCEAN (1976/77)

SOUTH PACIFIC (1976/77)

2

Quantityless than (%)
25

50 75 JOO

6
12
3
3

2
4

5
4
4
3
3

2
4

2

2

2

3
2

2

25 50 75 100

5
3
6

7
16
6
9
2
7
3
5

4
5
6
8
8
JO
4
4

3
2

Quantityless than (%)

I

8
20
5
3

3

3
2

2

c0.
s
i:Ll

Total
with
food

2
2

I
7
3
2
I
2

3

2

Total
with
food

2
7
12
12
2
3
6
3

APPENDIX TABLE II. NUMBER OF ANIMALS BY THE QUANTITY
OF STOMACH CONTENTS AGAINST LOCAL CATCH TIME
SOUTH PACIFIC (1977/78)
Quantity less than (%)
Empty
25

..i::

B
(';j
u

......
0

.§"'
OJu
0

....:I

6
7
8
9
JO
II
12
13
14
15
16
17
18
19

5
6
7
7
5
3
3
4
2
2
3
4
2

50

75

JOO

EASTERN INDIAN OCEAN (1978/79)
Total
with
food

25

50

75

JOO

2*
3*
3
2
3
2

2
3
4

2
3

2
2
2

2
2

2

2
2

3
5
3
7
9
2
3
3
7
8
7
2

* one stomach by fish food is included.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

Quantity less than (%)
Empty

6
9
5
4
3
5
2
4
JO

9
4
6

4**

2
2*
3
2
I*

2
2
2*
2

Total
with
food

4*
4
3
3

I

2
2
2

6
4
2
2
3
5
9
6
7
6

* one stomach by fish food is included.
** two stomachs by fish food are included.

MORPHOLOGICAL STUDY OF PELVIC BONES OF THE
MINKE WHALE FROM THE ANTARCTICHIDEO OMURA
Whales Research Institute, Tokyo

ABSTRACTIn the 1978-79 Antarctic whaling season a total of 72 pairs of pelvic
bone of the minke whale, 36 from males and 36 from females, were collected
for morphological study. The basic forms for males and females are thought
to be " drum stick " and " knife " respectively, as in the case in the North
Atlantic animals. There are, however, very wide range of variation both inmales and females and the individual sex can not be determined by the pelvic
bone alone.
Existence of ossified remnant of femur was noted in whales exceeding one
third of total whales examined, both in males and females.

INTRODUCTION

In the 1976-77 Antarctic whaling season a total of 51 pairs of pelvic bones of theminke whale, 50 from males and one from females, was collected by Japanese expeditions for morphological study. These results have suggested some doubts on sexual dimorphism of the bone, which was confirmed in whales from the North Atlantic, and the size of bones was thought to be a little smaller than those from theNorth Atlantic, and the presence of the ossified remnant of the femur was noted insome specimens (Omura, 1978).
In the 1978-79 season a total of72 pairs of pelvic bones, 36 from males and 36
from females, were collected by courtesy of Mr H. Kato on board the whaling factory ship Nisshin Nfaru No. 3. He joined the southern hemisphere minke whale assessment cruise 1978-79, a program of the International Decade of Cetacean Research of the International Whaling Commission, led by Dr Peter B. Best of theSouth Africa, and after conclusion of the cruise he remained in the factory and carried out biological investigation of whales treated in the factory. Dr P. B. Best
had also remained in the factory ship for some time and according to Kato he also
helped in collection of the sample. Material thus collected are the basis of thisstudy.
MATERIAL

The pelvic bones were collected from minke whales taken in the Antarctic during
a period from 18 January to 3 March 1979, in which period the expedition moved
from eastel'n part of the Area III eastwards to western part of the Area V. As
Sci. Rep. Whales Res. Inst.,
No. 32, 1980, 25-37

26

OMURA

shown in Table I bones were mostly or 75 percent of the total were collected in Area
IV. In this table are also shown distribution of body length classes, separately bysexes.
When sampling the bone care was taken in order to secure the remnant of thefemur, and thus much meat and other tissues were attached to the bones. Thesesamples were kept frozen in the factory ship and then transported to WRI.
At the laboratory these bones were boiled for some hours in order to remove
meat and other soft parts from the bone, each pair is being packed in a small
bag made of cotton cloth. Thus all solid bones were secured, even if a very small
remnant of femur was present. The bones were boiled again, after removal of allsoft parts, for extraction of oil and finally they were dried by direct sun. All ofthese bones are shown in Plates I-VII. Date and position and other catch particulars of whales from which bones were collected are shown in Appendix Table together with measurements of each bone.
TABLE 1. NUMBER OF MINKE WHALES FROM WHICH SAMPLES OFPELVIC BONES WERE COLLECTED IN THE 1978-79 SEASON
Body
lengthin m
5.5-5.9
6.0-6.4
6.5-6.9
7.0-7.4
7.5-7.9
8.0-8.4
8.5-8.9
9.0-9.4
9.5-9.9
Over 10.0
Total

Area IIIM

F

Area IV
T

M

F

Total

Area V
T

M

F

T

M

F

T

I

3
2

I
2
I
2

4
4
I
2

6
15
5

5

6

II

27

2
2
3
6
7
3
2
I*
27

3
2
9
21
12
3
2
54

I

3

4

3

4

12
17
5

7

36

2
2
5
9
9
5
2
I
36

3
3
17
26
14
5
2
I
72

M .. ·male, F .. ·Female, T···Total* 10.1 meter.

RESULTS AND DISCUSSION

According to Burmeister (1867) his whale of Balaenoptera bonaerensis was found dead,floating on the river Plata, near Belgrano, about ten miles from Buenos Ayres, by
a :fisherman, who brought the body on shore. This was a male of 32 feet (9.6 m)long and had the small bone of the pelvis, which is 7i inches (19.1 cm) long and
It inch (3.8 cm) broad in the middle, and of a lanceolate form, being narrowed
at both ends. Heyerdahl jr. (1973) found sexual dimorphism in pelvic bones ofthe minke whale from the North Atlantic, those of the female having the shape ofa knife while those of the male look like drum stick. Burmeister's "lanceolateform" may possibly similar to Heyerdahl's "drum stick". In my previous work
(Omura, 1978), however, there were wide range of variation in the shape of pelvic
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

PELVIC BONE OF MINKE

*

27

M.35

~

F26

60 80 100 120 140 160 180 200 220 240 260 280

LENGTH IN MM
Fig. 1. Comparison of length of pelvic bones of minke whales from the Antarctic
between males and females. The horizontal line represents the range; the vertical
midline, the arithmetic mean; the outer and inner boxes, the standard deviationand standard error on either side of the mean respectively. The numerals in the
figure are sample number of males and females.

'
WIDTH{THICKNEss{

I

~

M 35

+

' F 26

ElJ· M 35·EE· F 26
10

20

50
40
30
LENGTH IN MM

60

70

Fig. 2. Comparison of width and thickness of pelvic bones of minke whales from theAntarctic between males and females. See Fig. 1 for explanation.

bone of males, though only one sample from female showed the shape of a knife ingeneral.
In the 1978-79 season pelvic bones were collected from 36 males and 36 females, as shown in Table 1. Photographs of these bones of males are shown in
Plates I-III and Figs 1-3 of Plate VII and those of females in Plates IV-VI and
Figs 4-7 of Plate VII.
In these figures typical drum stick type may be observed in pelvic bones ofmales, for example Figs 1, 6 and 8 of Plate I, Figs 2, 8 and 10 of Plate II, Figs 5,
6 and 11 of Plate III. Typical knife shape are observed in pelvic bones offemales,for example Figs 1, 2, 6 and 7 of Plate IV, Figs 2, 4 and 7 of Plate V, and Fig.
4 of Plate VI. These two forms are thought to be the basic forms of the pelvic
bones of the minke whale from the Antarctic too. There are, however, a goodrange of variations both in males and females, and it is very difficult or nearly impossible to identify males and females only by the shape of these bones.
In Figs 1 and 2 pelvic bones of males and females are compared of their length, width and thickness. In these cases samples are taken from whales at or above
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

28

OMURA

I

I

WIDTH/[
LENGTHTHICKNESS/ [LENGTHTHICKNESS/ [
WIDTH

#J I
DfEJ

M 35

F 26

·ffi

M 35

Bf]

F 25

+

M 35

F 26

10

20

30

40

50

60.

70

80

90

100

PERCENT

Fig. 3. Comparison of proportion Width/Length, Thickness/Length, and Thickness/Width of pelvic bone of minke whales from the Antarctic between males andfemales. See Fig. l for explanation.

0
0

•

25~

•

0
0

f--

~ 20~

0.

'll
0

u

•
••

0

O,j>

• •
• • •I
•
•
• •
•
ooo
•
•
• ., •
•
•
•
0

0

0

~

,

LU

z
ra
u
0

0

0

0

> 15>--'
LU

0

0

0

0

Oe

c...

LL

0
:i:::I-

0

z

•

0
0

•

(!)
LU

-' 10

•

0

0
0

0
0
0

5~

•

0
I

0.1
0.3
0.5
0.7
0.9
RATIO THICKNESS/WIDTH

Fig. 4. Relation between length of pelvic bones and ratio Thickness/Width acrossthe promontry in minke whales from the Antarctic. Closed circle indicates maleand open circle female.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

29

PELVIC BONE OF MINKE

0

25

::?
u

z

20

w

z

0

flJ
0

u

> 15

0

•• • ••
•

...J

w

a.
LL

0

:c

•

•

0

I-

<.:)

zw

10

0

•

...J

0

•

0

5
5
15

6

7

8

9

10

M

20
25
30
35 F
BODY LENGTH OF WHALE

Fig. 5. Relation between length of pelvic bone and body length of minke whales
from the Antarctic. The straight line in the figure is the regression line obtainedby Hyerdahl jr. (1973) for minke whales from the North Atlantic. Closed circle
indicates male and open circle female.

average body length of sexual maturity or 7.2 m or over in males and 8.0 m or overin females (Ohsumi and Masaki, 1975). As seen in Figs 1 and 2 there are no distinction between males and females in the length and width of pelvic bones, butsome difference is present in the thickness, in males the bones are somewhat thicker
than those in females in general. Width and thickness of bones are measured attheir promontories.
In Fig. 3 the proportion width/length, thickness/length, and thickness/width ofpelvic bones of minke whales from the Antarctic between males and females are.
compared. In these cases the distinction between males and females is only noted
in ratio thickness/width, but in this case too ranges are overlapping in most parts,
suggesting difficulty of identification of sexes individually by means of pelvic bones
only.
In Fig. 4 the ratios thickness/width of the pelvic bones across the promontory
are plotted against respective length of the bones. Heyerdahl jr. (1973) found thatthe female bones tend to maintain their proportions while the male bones diverge
towards a rounder shape, with the increase of length of the bone. As seen in thisfigure no such tendency is obserbed in pelvic bones of minke whales from the Antarctic. There are wide range of variations.
Sci. Rep. Whales Res. Inst.,
No, 32, 1980

30

OMURA

In Fig. 5 the relation between length of pelvic bone and body length of minke
whales from which respective bones were obtained. The straightline in this figureis the regression line obtained by Heyerdahl jr. (1973) for minke whales from theNorth Atlantic. No such regression line can be drawn for minke whales from theAntarctic. It is possible, however, in minke whales from the Antarctic the pelvic
bones are smaller than those of minkes in the North Atlantic, as already noted in
the preliminary report (Omura, 1978).
Presence of ossified remnant of femur in the minke whales from the Antarctic
was already reported in the preliminary report (Omura, 1978), but in that report
the occurrence was 25 percent against the total of 51 pairs investigated. This percent of occurrence was very higher than those from the North Atlantic. Heyerdahl jr. (1973) reports none disclosed any trace of a femur, with the exception of
one of the 32 X-ray photographs. This was from a 25-ft (7.5 m) female minke
whale, with remnants of femur anterior and lateral to the promontory.
TABLE 2. OCCURRENCE OF FEMUR IN PELVIC BONESOF MINKE WHALES FROM THE ANTARCTIC
Male
Area

No.
examined

FemaleFemur
presentNo.
examined

Femur
presentNo.
examined

6
27
3
36

4
9
0
13
36. I

II
54
7
72

5

I

27

11

v

4

Total

36

2
14
38.9

III
IV

%

Total
Femur
present
5

20
2
27
37.5

Occurrence

As seen in Table 2 in the pelvic bones collected in the 1978-79 season fromthe Antarctic the presence of ossified remnant of femur was amounted 37.5 percentof the total of 72 animals, showing much higher percent than in the 1976-77 season(Omura, 1978). This is clearly due to the fact that a special caution was paid whensampling the bone, not to miss the bone even it is very small.
The size of the ossified remnant femur bones is different individually and in
most cases they present on both sides, but in some specimens it exist only on.one side. Measurements of three dimentions of these bones are given in the Appendix Table. Usually these bones are present anterior and lateral to the promontory and apart from the main bone. There present, however, clear articulating
tubercles both in the main bone and femur in some specimens and in the extreme
cases these bones are completely fused together, as shown in Figs 2 and 6 of Plate
IV and Fig. 8 of Plate V.
Burmeister (1867) found no trace of femur in his specimen of Balaenoptera
bonaerensis and describes "No vestige of an attachment of another bone to any partof its surface is visible; and it is the same with the European species, according tothe observation of Eschricht and Reinhart". Since then most authors followed
this opinion and Hosokawa (1951) classified baleen whales into the following three
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

NKE
NE OF MIPELVIC BO

1
3

imb.
ehindl
h
ot
ngt
ni
tai
r
e
nsp
o
t
e
kel
ys
tar
men
heruditoftinoheviewp
sfromt
group
two
叩
h
e
p
e
h
t
s
e
d
i
s
e
b
s
a
h
,
s
g
n
o
l
e
b
e
l
a
h
w
t
h
g
i
r
d
n
a
l
n
e
e
Gr
e
h
t
h
c
i
owh
,t
Group 1
er
h
t
o
h
c
i
h
w
n
i
,
2
p
u
o
Gr
.
)
a
i
b
i
t
d
n
a
r
mu
e
f
(
s
e
g
a
l
i
t
r
a
sofc
ybone
ar
di
i
s
ub
sofs
r
i
pa
e
l
a
h
w
n
i
f
e
h
t
,
k
c
a
b
p
m
u
h
e
h
t
s
e
s
i
r
p
m
o
c
,
t
en
s
e
spr
efemuri
h
lyt
son
lvi
e
ep
h
thant
t
u
b
a
i
b
i
t
r
o
n
r
mu
e
f
r
e
h
t
i
e
n
s
hha
c
,whi
e. Group3
ewhal
u
l
heb
ot
s
l
rhapsa
andpe
.
)
e
k
n
mi
(
e
l
a
h
w
n
i
f
r
e
s
s
e
hel
iwhaleandtehes
etocompris
emst
e
,s
y
l
川 on
hepeh
st
ha
,
)
9
6
9
,1
.
l
ta
Omuraeecan beadded (
twhal
igh
ckr
a
l
heb
ot
s
sgroupIal
Inhieheminkewhal
nt
emuri
ef
h
eoft
enc
t
s
. Exi
d
e
i
f
i
s
los
l
swerea
emur
ef
s
a
isc
h
nt
andi
a
s
a
w
e
n
o
b
e
h
t
n
e
m
i
c
e
p
s
s
i
h
n
i
h
g
u
o
h
t
,
)
3
7
9
1
(
.
r
j
l
h
a
d
r
e
y
He
cedby
i
tnot
s
r
i
wasf
n
efemuri
h
eoft
enc
t
s
i
x
hee
tt
ha
ovedt
twasprtudyi
iss
hage. Intiltnoduleofcar
l
a
t
o
t
e
h
t
f
o
d
r
i
h
t
e
n
o
d
e
d
e
e
c
x
e
g
n
i
e
e,b
ar
snotr
ci
i
t
c
r
a
t
巴 An
h
om t
r
minkewhalesf
e
h
t
n
o
s
k
r
o
w
s
u
o
i
v
e
r
p
my
n
I
e.
emal
nmaleandfd,bothineminkewhalesexami
o
ls
976)a
,1
a
975;OmuraandKasuy
7,1
5
9
a,1
O mur
es(
l
heminkewha
noft
o
et
l
ke
s
c
n
e
s e
hepre
smad巴 ont
ementwa
at
t
als
i
c
pe
,butnos
d
e
t
r
o
p
e
swerer
cbone
i
v
hepel
t
s
e
vhal
nkev
cbonesofmi
vi
沌 l
nofl
o
i
t
c
ecole
h
nt
edi
tnot
s
r
i
sf
twa
emur. I
hef
oft
f
o
me
o
s
d
e
s
u
e
v
a
h
I
.
)
8
7
9
1
刊
r
u
m
O
(
n
o
s
a
e
s
7
7
‑
6
7
9
1
e
h
t
n
i
c
i
t
c
heAntarfrom t
.
)
6
.
g
i
F
(
8
7
9
1
d
r
a
c
s
a
m
t
s
i
r
h
C
e
h
t
f
o
aph
r
g
o
t
gpho
n
i
ver
rco
o
themf

d
e
ct
le
o
ec
L
i
c
r
a
t
eAn
h
mL
o
r
sf
e
l
a
h
ew
k
n
emi
h
ft
so
ne
o
cb
i
lv
e
ep
h
fL
meo
o
. S
.6
g
i
F
.
n
o
i
t
a
n
a
l
p
x
e
r
o
f
t
x
e
t
c
e
S
.
n
o
s
a
e
s
7
7
‑
976
e1
h
nt
i
emur
rf
he
t
.nei
.e
oup3i
isgr
nh
oi
s
eal
l
eiwha
hes
st
e
lud
nc
951)i
1
okawa(
Hos
onof
t
e
l
e
k
s
f
o
t
e
s
e
t
e
l
p
m
o
c
A
.
l
u
f
t
b
u
o
d
e
b
y
ma
s
i
h
t
,
r
e
v
. Howe
t
en
s
e
apr
i
b
i
nort
r
o
7f
7
9
1
n
i
d
e
n
i
a
t
b
o
s
a
w
,
e
l
a
h
w
i
e
s
e
h
t
f
o
s
e
iv
t
a
l
e
er
os
l
yc
c,averlahveBrydesv
h
t
‑
m
o
c
n
e
e
b
t
o
n
s
a
h
y
d
u
t
s
e
h
T
.
e
pher
nhemisr
theouhes
udyfromttaxonomics
het
t
.
s
emur
iedf
f
si
hos
t
swi
cbone
vi
rofpelehadapai
ewhal
h
,butt
dyet
e
t
e
l
p
:KNOWLEDGιMENTS
AC.
.B
eandDrP
tut
i
t
hIns
c
r
a
e
s
esRe
eW halhoMrH.Katooft
dt
e
t
deb
n
hi
Iammuc
‑
c
a
f
e
h
t
d
r
a
o
b
n
o
s
e
n
o
b
c
i
v
l
e
p
e
h
t
f
o
s
e
l
p
m
a
s
f
o
n
o
i
t
c
e
l
l
o
c
r
o
f
a
c
i
r
f
A
tofSouth
s
Be
.
t
u
o
d
e
i
r
r
a
c
e
b
t
o
n
d
l
u
o
c
y
d
u
t
s
s
i
h
t
p
l
e
h
r
i
e
h
t
t
u
o
h
t
i
W
.
3
uNo.
r
a
l
l
¥
nJ
hi
pNiss
i
h
ys
r
o
t
,
.
t
s
n
s.I
sRe
e
l
a
h
V
.I
1
/
.Re
i
c
S

＇

,1980
2
.3
λo

OMURA32

My sincere thanks are also due to the crew of the factory ship who helped the collection and transported them to vVRI.
REFERENCES
BURMEISTER, H., 1867. Preliminary description of a new finner whak (Blaenoptera bonaerensis). Proc. Z,ool.
Soc. Lond. XLVI: 707-713.
HEYERDAHL JR. T., 1973. Sexual dimorphism and age criteria in the pelvic bones of the minke whale,
Balaenoptera acutorostrata Lacepecte. Norwegian J. Zoology, 21 (1): 39-43.
HosoKAWA, H., 1951. On the pelvic cartilages of the Balaenoptera- foetuses, with remarks on the specificaland sexual difference. Sci. Rep. Whales Res. Inst. 5: 5-15.
OHSUMI, S. and Y. MASAKI, 1975. Biological parameters of the Antarctic minke whale at the virginal polulation level. J. Fish. Res. Board Can., 32: 995--1,004.
OMURA, H., 1957. Osteological study of the little piked whale from the coast of Japan. Sci. Rep. Whales
Res. Inst., 12: 1-21.
OMURA, H. 1975. Osteological study of the minke whale from the Antarctic. Sci. Rep. Whales Res. Inst.,

27: 1-36.
OMURA, H., 1978. Preliminary report on morphological study of pelvic bones of the minke whale from theAntarctic. Sci. Rep. Whales Res. Inst., 30: 271-279.
OMURA, H., S. 0HsUMI, T. NEMOTO, K. NAsu, and T. KASUYA, 1969. Black right whales in the North Pacific.
Sci. Rep. Whales Res. Inst., 21: 1-78.
OMURA, H. and T. KASUYA, 1976. Additional information on skeleton of the minke whale from the Antarctic. Sci. Rep. Whales Res. Inst., 28: 57-68.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

~

:;;-.

~

"""'~

~~

......

vf\v ~""~~~

78Nl493
78Nl562
78N1574
78Nl60378N 1637
78Nl414
78Nl450
78N1529
78Nl551
78Nl576
78N1643
78N1669
78N171078Nl746
78N1801
78N1865
78N1885
78N1928
78N1966
78N1985
78N2016
78N2070
78N2138
78N2176
78N2201
78N2210
78N2213Whale No.

8
9
10
12
13
14
15
16

Si?

18
19
21
22
25
26
27
28
29
2 Feb. '79
3
4
5
6

cI

cI

Sex

20 Jan. '79
24
25
26

Date, catch

8.4
7.8
8.4
7.6
7.6
8.3
8.4
7.6
9.0
9.2
8.5
8.7
8.5
8.3
8.5
8.4
8.2
8.3
7 .8
8.3
8.6
8.6
8.2
7.9
8.2
7.5
8.0

m

Body
length68°-10 1 E
67°-58 1 E
68°-14 1 E
68°-04 1 E
65°-02 1 E
65°-15 1 E
71°-48'E
72°-ll 1 E
73°-09 1 E
74°-34 1 E
72°-46 1 E
73°-26 1 E
73°-53 1 E
74°-00 1 E
73°-18 1 E
74°-01 1 E
78°-25 1 E
89°-55 1 E
92°-441 E
94°-52 1 E
98°-53 1 E
104°-08 1 E

67°-21 1 S
67°-24 1 s
67°-32 1 s
67°-34 1 s
67°-101 s
67°-05 1 s
67°-09 1 s
69°-58 1 s
67°-46 1 s
67°-46 1 s
67°-38 1 s
67°-47 1 s
67°-52 1 s
67°-56 1 s
67°-11' s
67°-19 1 s
66°-14 1 s
65°-42 1 s
64°-51 1 s
63°-50' s
64°-02 1 S
64°-401 S

1

68°-39 E
62°-02 1 E
65°-02 1 E
65°-15' E

1

Long.

67°-20 s
67°-04 1 s
67°-10 1 s
67°-05 1 s

Lat.

Position, catch

IV

III

Area

162
144
189
222
114
201
201
80
197
169
213
172
69
253
153
170
177
173
202
185
89
158
211
205
191
147
169

26
28
37
58
49
63
44
32
30
34
50
22
21
28
29
41
35
32
24
37
27
40
40
36
48
31
20

22
14
18
14
11
13
22
10
13
13
18
18
16
22
19
24
25
19
19
23
24
22
26
16
24
11
10

Length Width Thickness

One side28,24,24
26,22,21
18, 15, 11
21, 17, 13
none
11, 8, 7
none
21, 21, 11
none
34,24,20
23, 19, 12
none

60,32,25
none
26,24, 18
22, 18, 16
42,25,21
none

none

Femur*

none

24, 19, 17
none
29,21,1723, 17, 14
none

25,24,20
26, 19, 16
noneContinned ...

150
29
21
138 . 27
14
174
40
18
230
62
14
112
47
13
Broken
122+
199
54
20
80
36
11
184
30
13
141
28
16
215
47
17
181
23
18
69
21
17
252
23
19
145
22
30
179
39
24
32
25
187
175
31
19
18
203
28
182
48
21
144
24
23
153
48
18
203
39
23
243
36
17
199
48
26
151
31
12
161
21
13

Femur*

31, 25, 16
none
43,21,22
none
26,22, 18
none
40,22,22
none

Another side
Length Width Thickness

Measurements in mm

APPENDIX TABLE. CATCH PARTICULARS OF THE MINKE WHALE FROM WHICH PELVIC BONESWERE SAMPLED AND MEASUREMENTS OF BONES (1978-79 SEASON)

"°
"°

~
t<:I

z

~

0".!j

~

°'

0

til
~
......

"" ~

~~
co~

~
~~

"°

~~
;:> '->

~

~

~

~

16 Jan. '79
17

78N2215
78N2252
78N2258
78N2300
78N2328
78N2379
78N2406
78N2422
78N2450
78N2488
78N2582
78Nl648
78Nl782
78Nl799
78Nl901
78N 1915
78Nl961
78Nl983
78N2017
78N2019
78N2109
78N2132
78N2169
78N2200
78N2208
78N2222
78N2224
78N2294
78N2325

18
19

15
16

II
12
13

9

8

18
19
20
21
22
23
24
26
27 Jan. '79
30
31
4 Feb. '79
5
6Date, catch

Whale No.

~

d'

Sex

10.1
7. I
9.5

8.8

8.3
8.0
8.0
8.4
8.3
9.7
9.0
8. 7
8.9
8.6
9.0
7.9

7.7
7.7
8.8
8.8

8.0
8.3
8.0
8.0
8.4
6.6

7 .8

8.0
8.2

m

Body
length65°-17 1 S
64°-51 1 S

109°-33 1 E
111°-181 E

98°-53' E
104°-08 1 E

85°-51 1 E
89°-55 1 E
92°-44 1 E

66°-07 1 s
65°-42 1 s
64°-51 1 s
64°-02 1 S
64°-40 1 S

109°-33 1 E
111°-18 1 E
114°-12 1 E
117°-09 1 E
117°-45 1 E
123°-45 1 E
125°-15 1 E
128°-47 1 E
71°-48 1 E
74°-01 1 E
73°-42 1 E
73°-20 1 E
73°-53 1 E
74°-00 1 E
73°-18 1 E
74°-01 1 E

104°-081 E
106°-15' E

64°-40 1 S
65°-04 1 S

65°-17 1 S
64°-51' S
64°-34 1 S
64°-29 1 S
64°-39 1 S
65°-18 1 S
65°-14 1 s
65°-04 1 s
67°-09 1 s
67°-46 1 s
67°-43 1 s
67°-47 1 s
67°-52 1 s
67°-56 1 s
67°-11 1 s
67°-19' s

Long.

Lat.

Position, catch

IV

Area

APPENDIX TABLE.

118
170
196
263
141
225

88

177
175
187
167
217
130
138
171
203
219
252
168
112
155
203
227
200
75
217
42,30,23
none
30, 14, 13
42,28,25
none

29,21, 15
none

26, 17, 14
36,23, 12
none
36,27,25
33,21, 17
none
25, 15, 12
none

none

23
9
17
20
21
19
15
23
12
14
22
17
12
17
13
16
14
13
22
16
17
18
21
12
12
16
17
12
13

46
49
40
28
34
34
22
36
44
21
53
48
28
50
31
26
49
19
60
39
26
51
24
21
44
60
34
22
41
194
95
194

Femur*One side

196
47
98
43
203
41
24
183
123
32
180
37
129
21
31
210
129
43
23
149
54
167
48
202
231
33
260
52
35
164
24
118
48
157
19
189
202
60
44
199
31
73
missed71
26
missed
44
168
193
61
263
32
26
143
40
219

12

11

12
16
18

22

18
9
17
19
22
18
14
20
II
13
21
18
13
16
14
13
15
14
21
16
15

none

Femur*

42,30,25
none

36,30,24
none

22, 15, 14
none

26, 17, 15
35,27, 12
none
40,28,26
40,24, 19
none

Another side
Length Width Thickness

Measurements in mm

Length Width Thickness

Continued.

'-"

~

~

0

"'"

:::.

~

"'

"

"'
:::;i

~

<;:,"'

~~

._

--~~

"":::;i~'.?'. ......
~

,,

,,
,,

,,

3
27 Feb. '79
28,,"
3 Mar. '79

,,
,,

,,

,,

,,
,,

<;2

,,

d

,,

"

,,
,,

,,
,,

,,

,,

21
,,
22
,,
23
,,
24
,,
25
"
25
"
26
,,
27
"
2 Mar. '79

,,
,,

,,
,,
,,
,,
,,
,,
,,
,,
,,
,,

,,

20

* Three dimensions.

78N2370
78N2371
78N2403
78N2432
78N2466
78N2493
78N2523
78N2544
78N2574
78N2614
78N2684
78N2699
78N2763
78N2618
78N2649
78N2725
7.6
7.0
8.3
6.9
8.9
5.5
7 .8
6.6
9.0
7.8
7.4
7.7
7.8
8. 7
8.3
7.8
64°-56 1 s
65°-07 1 s
65°-24 1 s
64°-56 1 s
134°-38 1 E
131°-22 1 E
131°-55 1 E
134°-38 1 E,,

128°-47 1 E
131°-22 1 E
133°-45 1 E

65°-04 1 s
65°-07 1 s
64°-55 1 s,,,,

117°-09 1 E
117°-45 1 E
123°-45 1 E
125°-15 1 E
127°-52 1 E

64°-29' s
64°-39 1 s
65°-18 1 s
65°-14 1 s
65°-18 1 s,,,,

114°-12 1 E,,

64°-34 1 s

,,
,,

,,
,,

,,

,,

v

,,
,,
,,
,,

,,

,,
,,
,,
,,
168
161
165
91
228
49
90
119
156
180
161
174
168
162
63
160

51
29
41
44
56
28
26
34
25
33
33
46
32
38
21
49
II

8

II

13
10
9
10
16
6
9
8
10
23
18
21
19

,,
,,

24, 15, 14
none
24,21, 17
none

,,

,,
,,

"

,,

none

31,25,22
none
20, 18, 16
15, 14, 12

161
49
166
28
170
47
broken223
54
missed
93
23
120
30
161
27
181
33
157
33
174
45
25
170
164
40
missed
44
157
II

II

10
8
10
23
23
22
15

18

13
9
8

,,
,,
,,

30, 19, 14
none

29,24,20
none
27, 22, 19
18, 15, 14
none

tTJ

(.)"1

""

tTJ

~

z>-<

~

"':I

0

ztTJ

0

t;;

n

~>-<

'"C

36

OMURA

EXPLANATION OF PLATES
Pelvic bones of minke whales from the Antarctic collected in the 1978/79 season.
PLATE I
Fig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.

78Nl493
78Nl562
78Nl574
78Nl603
78Nl637

Male

Fig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.

78Nl885
78Nl928
78Nl966
78Nl985
78N2016
78N2070

Male""

Fig. 6.
Fig. 7.
Fig. 8.
Fig. 9.
Fig. 10.

78Nl669
78Nl 710
78Nl746
78Nl801
78Nl865

Male

Fig. 7.
Fig. 8.
Fig. 9.
Fig. 10.
Fig. 11.
Fig. 12.

78N2138
78N2176
78N2201
78N2210
78N2213
78N2215

Male

Fig. 7.
Fig. 8.
Fig. 9.
Fig. 10.
Fig. 11.

78N2422
78N2450
78N2488
78N2582
78N2614

Male

Fig. 6.
Fig. 7.
Fig. 8.
Fig. 9.
Fig. 10.

78Nl643
78Nl648
78Nl 782
78Nl799
78Nl901

FemaleFig. 7.
Fig. 8.
Fig. 9.
Fig. 10.
Fig. 11.

78N2132
78N2169
78N2200
78N2208
78N2222

FemaleFig. 7.
Fig. 8.
Fig. 9.
Fig. 10.
Fig. 11.

78N2432
78N2466
78N2493
78N2523
78N2544

Female"PLATE II""
PLATE IllFig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.

78N2252
78N2258
78N2300
78N2328
78N2379
78N2406

Male

Fig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.

78Nl414
78Nl450
78Nl529
78Nl551
78Nl576

FemaleFig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.

78Nl915
78Nl961
78Nl983
78N2017
78N2019
78N2109

FemaleFig. I.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.

78N2224
78N2294
78N2325
78N2370
78N2371
78N2403

Female""""PLATE IV"""
PLATE V"""""
PLATE VI

"
"
"
"

"

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

PELVIC BONE OF MINKE

37

PLATE VII
Fig. I.
Fig. 2.
Fig. 3.
Fig. 4.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

78N2684
78N2699
78N2763
78N2574

Male

Fig. 5.
Fig. 6.
Fig. 7.

78N2618
78N2649
78N2725

Female

d
I
V'
J.
I
・
'
I.

句V
￡・
l
08Gf'

S
"
.
l ・＜l•u '
呪l
／υ
l]SJ
S2
J・
l
l
S
/
'
.

JO
'
t
J
1
V1Jf

PL
ATE I
I

O M URA

S
c
i
.Re
/
1
.1
1＇
・
＂
h
a
l
e
sRe
s
.[1
1
5
1
.
,
λr
o
.32,1980

i
e
LLV l
'
1.
1
1

N
O
;"
f
t
1"
6
8
0
S
J
!
1JH "
1・
NSJfll呪1
J・／SIザ目 I
・V ~I 「)Jへ10

P
la八γE I
¥'

Oi¥!
U R八

S
c
i.Re
p
.1
1
'
/wl
e
sRe
s.fi1JI.、人lo.32, 1980

l
c
l
'
ILV
.・
＇
人

ON
t'
Z
086!'
＇S
！
j・
i
J
Q
1・
I
;
f
l
V
/
J
jS
i
J
S
印 ［'
1
・
'

吋O
V"8nl

PしATE ¥'
I

OMURA

Sc
i.Re
p
.1
1
'
/
w
l
e
sRe
s./
n
1
1
.
,

Ao.32 1
.
9
8
0

1
v1,
1＼−：u.
1

ON
u・
OB6r'
S
'
!
y"
a
f
<
1・
虻l
u f勾υ
a
s
1I・
s
1
"
'

吋O
v~rn IAGE DETERMINATION AND AGE RELATED FACTORSIN THE TEETH OF WESTERN NORTH ATLANTIC
BOTTLENOSE DOLPHINSALETA A. HOHN
Division of Mammals, Smithsonian Institution, Washington, D.C.

ABSTRACT

Teeth were taken from 120 bottlenose dolphins, Tursiops truncatus, which
had stranded on the mid-Atlantic coast of the United States. The number ofannual growth layer groups (GLGs) for each animal was used to construct a
growth curve. The growth rate of coastal North Atlantic Ocean Tursiops issimilar to other cetaceans in having a high initial rate of growth, with no differences in growth between females and males. In females, the first dentinal
GLG is thickest and is followed by GLGs which become progressively narrower. In males, the second GLG is thicker than the first; GLGs beyond
number two become progressively smaller but at a slower rate than in females. In males and females, the translucent layer makes up proportionallylarger parts of the GLG as the animal ages, but in males the percent translucent layer remains constant at about 50% while in females it continues toincrease up to about 70% of the GLG. These two factors, GLGs width andtranslucent layer width, indicate that the sex and age of the animal influence
the deposition of GLGs. Incremental layers are also present, averaging 12
per GLG, and seem similar to incremental layers described in other marine
mammals. A plot of the relationship of percent growth of the last GLG totime of death suggests that the deposition of GLGs is relatively constant,at least during the first half of the year, and that North Atlantic Ocean
Tursiops give birth in the fall as well as in the spring.
INTRODUCTION

Owen (1945) documented the existence of "concentric layers of dentine" in odontocete teeth and, similarly, the "appearance of opaque striae or conecntric layers"(pg. 512) in polished sections of pinniped teeth. Lankester (1867) also noted alayering pattern in the teeth of a beaked whale, Z,iphius sowerbiensis (=Mesoplodon
bidens), but did not suggest a reason or use for them. In 1950, Scheffer suggested
using these layers as a method of age determination when he found layers in thedentine and cement of a fur seal, Callorhinus ursinus, canines that corresponded to
the known age of seals branded as pups and recovered up to eight years later.
Laws (1952, 1953) suggested using dentinal layers in odontocete teeth as a measureof age when he found layers in sperm whale teeth similar to those in pinniped teeth.
In the following years, dentinal growth layers (growth layer groups) were discovered and used as age indicators in Stenella coeruleoalba (Nishiwaki and Yagi, 1953,
Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 39-66

40

HOHN

1954)i, Berardius bairdii (Omura et al., 1955), and sperm whales (Nishiwaki et al,1958).
In 1959, Sergeant described growth layer groups (GLGs) in the teeth of fourbottlenose dolphins, Tursiops truncatus, from Marine Studios in Florida. Two of theanimals were bor'n and died in captivity; two were wild caught and died in captivity. In each case the number of GLGs in the teeth corresponded with the known
or estimated age of the animals based on their time spent in captivity. The oldest
animal was estimated to be 15.5 years old and had 17 GLGs. He also examineda few teeth from the pilot whale, Globicephala melaena, and one each from the Atlantic whitesided dolphin, Lagenorkynchus acutus, and the common dolphin, Delphinusdelphis. All of the species demonstrated layering in the dentine similar to that of
Tursiops, which was identical to that described by Nishiwaki and Yagi (1953) for
S. coeruleoalba.
Since Sergeant's paper, dentinal GLGs have been used extensively for age determination of odontocetes. Most of the work has centered on direct applicationof the technique, predominantly for species involved in fisheries, for example, sperm
whale (Gambell and Grzeborzewska, 1967; Best, 1970; Gambell, 1977), delphinids(Sergeant, 1962, 1973; Kasuya, 1972, 1974, 1976; Sergeant et al., 1973; Kafaya etal., 1974; Perrin et al., 1976, 1977; Ross, 1977), the white whale (Sergeant, 1962),
Baird's beaked whale (Kasuya, 1977), harbor porpoise (Nielsen, 1973; Gaskin andBlair, 1977) and Dall's porpoise (Kasuya, 1978). However, some aspects of age determination and age related factors visible in the teeth of odontocetes have been
examined but not satisfactorily explained in many species. Some of these include
description and clear identification of GLGs, formation rate of the layers, identification of accessory layers and the more recently discovered incremental layers, andsexual dimorphism.
Since GLGs were first suggested as a means of aging odontocetes much controversy has prevailed over the meaning of these layers, but for the most part theassumption has been that GLGs are deposited annually. However, in a few species evidence based on relative age indices indicates that GLGs are not annual.
In the white whale, Delphinapterus leucas, Sergeant (1962) and Brodie (1969) haveshown circumstantially that more than one GLG is deposited at least during theearly growth of the animal, although Khuzin (1961) felt that only one GLG is formed each year. In the narwhal, Monodon monoceros, a species related to the white
whale, Hay (in press) also feels that more than one GLG is formed. Kleinenberg
and Klevezal (1962) found twice as many dentinal GLGs as maxillary bone layers
in the Black Sea dolphin, Delphinus delphis. In sperm whales, Ohsumi et al. (1963)
determined that one GLG is formed each year based on 11 whales captured sevento 16 years after being tagged, a rate which Best (1970) confirmed when he followed
the growth of the tooth from samples which extended over six months of the year.
Berzin (1961, 1964) and Gambell and Grzegorzwerska (1967), however, concluded
from samples taken throughout the year that two GLGs are deposited annually.
Perrin et al. (1977) suggest three possible hypotheses of rate of deposition of GLGs
in the spinner dolphin, Stenella longirostris, after examining 2500 specimens, none of
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

41

which is that just one layer is set down per year. They accepted the hypothesisthat 1.5 GLGs are deposited in the first year, while one GLG is deposited in allother years, rather than a rate of 1.5 GLGs per year or 1.5 GLGs per year until
puberty and one GLG per year thereafter.
Direct evidence on the rate of dentinal growth has supported an annual formation rate. Sergeant's (1959) finding that the number of GLGs in Tursiops teeth
correlated with the known age or minimum known age for each animal offered thefirst measure. Similarly, in 1973, Sergeant et al. reported that in three captive
Tursiops from Marin eland of Florida the number of G LGs was approximately equal
to the known age of the animal. Klevezal and Kleinenberg (1967) examined captive and wild specimens from nine orders of mammals, including cetaceans, andconcluded that GLGs are an annual event. Tetracycline injected specimens havealso supported an annual deposition rate of GLGs (Best, 1970; Gurevich and Stewart, in press; Perrin and Myrick, in press).
Divergencies of opinion on the periodicity of GLG formation within a species
probably can be attributed to the presence of accessory layers, thin layers similar
to the hypomineralized layer of the GLG. Klevezal and Kleinenberg (1967) proposed that all odontocetes form one GLG per year but in some species accessory
layers are especially distinct, being almost indistinguishable from an annular layer,
so that it appears as though two GLGs are deposited annually in some species.
More commonly, however, accessory layers are not quite so distinct and may influence the count of GLGs to the extent that repeated counts on the same tooth by
one person or several people tend to give different results (Kasuya et al., 1974; Perrin, 1975; Kasuya, 1977; Kimura, in press; Perrin and Myrick, in press). The
clear distinction between an accessory layer and a GLG boundary layer is still not
defined in some species, for example, the killer whale (Orcinus orca), nor is the causeof accessory layers known.
_
Before the discovery of "annual" growth layers in dentine, research in dental
histology had shown the existence of smaller incremental growth patterns. In 1934,
Schour and Smith showed that in the continuously growing rat incisor 16 micro-·meters of dentine are laid down in 24 hours. In 1935, Schour and Steadman described an incremental stratification, also in the rat incisors, which appear as a succession of dark (well calcified) and light (less calcified) layers, the width of eachpair totaling 16 µm. Further examination (Schour and Hoffman, 1939) showed
the same 16 µm incremental mineralization pattern in 17 other species including
fish, a shark, crocodile, mastodon, and several species of mammals, including man.
These lines were later interpreted as incremental lines of von Ebner. Yilmaz, Newman and Poole (1977) described daily von Ebner lines in pig dentine where eachband consisted of parallel light and dark portions in thin sections of teeth. These
were probably equivalent to 5 µm daily von Ebner lines described by Krauss andJordan (1965) and Newman and Poole (1974). Von Ebner lines have recently
been described from the teeth of Stenella, where about 365 lines were counted within GLGs (Myrick, in press). Although their deposition rate has not been measured directly, the frequency of these von Ebner lines in the dolphin teeth suggests
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

42

HOHN

that they represent a daily growth pattern.
In 1970, Scheffer found still a different frequency incremental layer in thin sections of a Dugong tusk. ·He described a pattern consisting of "coarse layers" and "finelayers". Kasuya and Nishiwaki (1978) found the same pattern in captive dugongs
where they defined coarse layers as annual growth layers or GLGs. There were 10
to 15 fine layers within each coarse layer, so the fine layers were suspected to bedeposited on a monthly or lunar cycle. Kasuya (1977) found the "long cycles"(GLGs) in Baird's beaked whale teeth to contain many (11.0 to 13.4) "short cycles".
Myrick (in press) noted incremental layers of the same periodicity in thin sections
from teeth of several species of dolphins. In addition, scanning electron micrographs of a small sample of etched Tursiops teeth also showed subannual incremental
layers, larger than van Ebner lines, which probably represent the same growth pattern seen by Myrick and Kasuya, appearing as a finer mineralization pattern within the mineralization pattern of the GLG (Hohn, in press). Although the deposition rate of these incremental layers has not been measured directly, this circumstantial evidence suggests a "monthly" growth or mineralization cycle which may
be useful for more precise age determination, possibly back-dating the month ofbirth in young animals, or a better understanding of the mineralization patterns in
dentine.
Sexual dimorphisms have also been described in the teeth of some odontocetes. The identification of sexual dimorphism in the growth of teeth has two
advantages. First, skeletal material currently in museum collections that is missing
data on sex may be more useful for systematic or other research if the sex can be
determined from the material on hand, such as the teeth. Secondly, differences in
the growth of teeth or other mineralized tissue probably reflects differences in habits
or intrinsic factors between the sexes. These differences may help explain the causeof formation of growth layers.
Van Utrecht (1969) found a sexual dimorphism in the extent that the neonatalline overlaps the cementum in teeth of the harbor porpoise, Phocoena phocoena, anda small sample of the white-beaked dolphin, Lagenorhynchus albirostris. Although
Nielsen (1972) confirmed this finding in the harbor porpoise, it has not been described in other odontocetes. Another sexual dimorphism in the teeth of Phocoena
is found in the ratio of the width of the opaque layer to the width of the translucent
layer (Gaskin and Blair, 1977). In males, this ratio. remains constant while infemales it decreases steadily with age. Gaskin and Blair (1977) also found differences in the amount of dentine deposited annually, which they attributed to size
differences of the sexes at any given age. Similar or additional sexual di morphisms
in the teeth have not been described in other odontocetes.
The purpose of this study is to describe dentinal GLGs and accessory layers,
including their appearance and position, in western North Atlantic Ocean bottlenose dolphins; to examine age-related changes in GLG deposition and any sexual
dimorphisms in dentinal characteristics; and to construct a growth curve for coastal North Atlantic Ocean bottlenose dolphins.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTILENOSE DOLPHIN

43

MATERIALS AND METHODSThe Sample.

Teeth were collected by the Smithsonian Institution's Marine Mammal Salvage Program (MMSP) from Tursiops stranded along the Atlantic coast of theUnited States between South Carolina and New Jersey. 118 of these animals
have complete data, including sex and total length. Two specimens were missing at least one piece of data and were included for GLG counts but not in otheranalyses.

Preparation of Sections
At least one tooth was taken from each specimen. A medial longitudinal cut
was made on each of the teeth on a Buehler lsomet 11-1180 low speed saw using
a rotating diamond blade with a saw speed of 5 to 6 on a relative scale of 1 to 10(up to 300 rpm), following the method of Hohn (in press). One of the halfsections from each tooth was prepared for scanning electron microscopy. These
were soaked in 5% formic acid for 3 hours, rinsed in water for at least one-halfhour to remove the acid, cleaned in an ultrasonic cleaner with acetone. for 15 to 60
seconds to remove extraneous surface particles, dipped in 70% ethanol to dehydrate
and air dried. These etched sections were examined by scanning electron microscopy (SEM) (Hohn, in press). During an SEM session, a standard set of micrographs was taken which included serial micrographs of the entire tooth at low magnification (15 to 20 X ), requiring up to five micrographs, and higher magnifications(greater than 25 X) for difficult to count, narrow GLGs, GLGs bordering the pulp
cavity, and possible incremental layers. Specimens were prepared for SEM not
more than two or three days before each session to help reduce their absorbing
moisture.
For each tooth, a 150 µm thin section was also prepared. In most cases, thecut surface of the remaining half section was glued to a microscope slide and all
but 150 µm cut off leaving the thin section adhering to the slide. The thin sections
were removed by dissolving the adhesive in acetone, then mounted for examination
on a clean slide.

Data Collection and Anafysis
GLG counts were made for all of the specimens from the SEM micrographs
and from the thin sections using a dissecting microscope with transmitted light (at25 X ). The number of GLGs was plotted against total length for each animal.
The total length of animals in each of the first 3 age classes (GLGs) was comparedfor males and females to examine differences in growth rates. The sample sizes
were too small for statistical analyses for animals with more than four GLGs.
Measurements for GLG and translucent layer widths were taken for 19 females
and 19 males from the thin sections using a dissecting microscope (at 50 X) equipped with an ocular micrometer and a polarizing filter. Measurements of the first
few GLGs were made near the base of the neonatal line on the concave side of theSci. Rep. Whales Res. Inst.,
No. 32, 1980

44

HOHN

tooth. In sections in which it was difficult to measure at this point because of unclear boundaries, the GLG width was determined closer to the crown or tip of the
tooth. The width of the first GLG is approximately the same from the base of theneonatal line to below the crown so a slight change in position did not affect themeasurements. Later layers were measured where they were most clearly defined but in the upper half of the length of the GLG before it becomes compressed in
the root, and below the apical end where the layers are especially wide. Sections
that did not allow determination of boundaries of adjacent G LGs were not included.
Preliminary examination suggested the growth of the tooth by width of GLGs
to be different in males and females. To test this, the width of each GLG was determined for each sex and compared using a Mann-Whitney Rank Sum test. In
addition, the ratio of width of the translucent layer to entire GLG was plotted against GLG number, again considering males and females separately.
The optical density and extent of growth of the last GLG were determined andplotted against time of death for 16 males and 12 females whose teeth had fewer
than four GLGs. Older animals were excluded because the GLGs become too narrow, and sometimes the boundaries too irregular, to get accurate measurements ofa partial layer.
Incremental layers and accessory layers were treated separately. The numberof incremental layers per GLG was determined where all of the increments of a
GLG could be distinguished. The widths of individual increments were measured
by position within different GLGs, i. e., on a ridge or in a groove for GLG 1, 2, or
3, or beyond GLG 3, using the SEM micrographs. The distribution and appearance of irregular accessory layers was noted. For accessory layers that appeared
more regularly, their position within the GLG was measured.
Five variables were tested specifically for possible sexual dimorphism related
to the neonatal line. First, the extent of the neonatal line beyond the bottom of
the enamel was measured in thin sections on the concave and convex side of 42
teeth from mixed males and females. This is similar to the study by van Utrecht(1969). In addition, the width of the prenatal zone at the base of the enamel was
determined, also from thin sections on both sides of the tooth. Finally, the widthof the translucent neonatal line was compared in females and males. Means foreach measurement were compared for males and females using a Student's t-test.
RESULTSAge and GrowthA scatterplot of 64 females, 54 males and two specimens of unknown sex shows
the general growth curve for Tursiops from the western North Atlantic Ocean (Fig.
1). For each of the first few age classes, including neonates, and for a cumulative
average for animals with more than four GLGs, the mean total length is not significantly different for males and females using a Mann-Whitney test (Table 1). The
minimum and mp.ximum total lengths within each age class indicates the large overlap in total length of individuals in different age classes. The decrease in growth,
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

45

300
280

••

260

~ 240

2{

~ 220

c:Ji

~

I-

~ 200

z

~ 180
f-

120
100

•••

••

ic:i
l{i)

:;i 160
~ 140

(!)

c:J6

66

~

~

(!)

80 '"-:o!:--:2=--4':---'.5=--8=--170~17
2-1~4~1~6~1~8~2~0~2~2-2~4-2~6--='28

NUMBER OF GLGS
Fig. 1. Scatterplot of the number of growth layer groups (GLGs) to the nearest
half-GLG and total length for 120 western North Atlantic Ocean Tursiops. Circles
are females, triangles are males, diamonds are animals whose sex is unknown.
Solid symbols represent a closed pulp cavity.

TABLE l.

SOME DESCRIPTIVE STATISTICS FOR TOTAL LENGTHSOF TURSIOPS BY NUMBER OF GLGS AND SEX
Total Length (cm)

No. of GLGs

Sex

N

0
(Neonates)

F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F&M

9
9
0
2
6
9
2

0.5

1.5
2
2.5
3
4
More than
4 GLGsSci. Rep. Whales Res. Inst.,
Na. 32, 1980

11
8
2
1
6
8
4
2
24
14
38

Mean

Min.

Max.

116
118

95
110

132
134

153
180
172
184
198
183
196
207
191
210
203
220
220
249
250
250

146
155
143
183

159
200
189
185

168
174
206

205
210
207

205
189
214
216
232
226
226

223
217
227
223
275
284
284

HOHN

46

large ranges in total length, and small sample size for animals with more than four
GLGs allows for the determination of average "adult" total length of approximately 250 cm.

Description of GLGs
For the most part, GLGs in thin sections of teeth of these Tursiops appear as
described in other odontocetes, particularly delphinids and Tursiops (Sergeant, 1959),
as alternating translucent and opaque layers (see Perrin and Myrick, in press).
The prenatal zone is a relatively uniform area easily distinguished by its lack of
substructure, e. g., incremental and accessory layers, seen in post-natal dentine.
700
600
500

0

tl 400

.A

A

:r:

s

0

s 300

(,!j

200
100

.......

o~~~~~~~~~~~~~~~~

0 1 2 3 4 5 6 7 8 910111213141516

GLG NUMBER
Fig. 2. Average width of GLGs for females (circles) and males (triangles), in micrometers. Measurements based on thin sections of teeth from Tursiops.

The neonatal line is a narrow translucent layer usually followed by a narrow, intense opaque layer. The first GLG begins after the neonatal line with a wide,
variably opaque layer riddled with accessory layers, and ends with a narrow translucent layer often less apparent than some of the accessory layers. The second
GLG is similar to the first in having the wide, variably opaque layer followed bya narrow, relatively, but indistinctly, translucent layer. The third and sometimes
fourth GLGs have more distinct opaque and translucent layers and, although accessory layers can still be seen, they are not as overwhelming as in the first two
GLGs. Subsequent GLGs have better demarcated opaque and translucent layers,
less variability in mineral densities within a layer, and fewer accessory layers.
The same basic description is applicable to etched half-sections where opaquelayers are equivalent to grooves and translucent layers are equivalent to ridges.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

47

AGE OF BOTTLENOSE DOLPHIN

However, the numerous accessory layers in the first few GLGs are usually not asprominent in the etched sections. The exception is when the mineral density differences, normally accentuated by etching, are small across a GLG (usually in thefirst two GLGs), then incremental layers and accessory layers in the opaque zoneof the GLG are almost indistinguishable from the translucent (boundary) layer of
the GLG. This also occurs in thin sections. Furthermore, in etched sections,
there are not clear boundaries between GLGs, i.e., there is not an abrupt end to
the translucent layer or ridge. Rather, the topography of the surface might belikened to rolling hills with a rounded crest and slopes, and valleys inbetween.
This does not allow for clear points or ends of layers from which to make measurements.
In general, the widths of GLGs decrease as the animals get older (Fig. 2).
The first few GLGs are the largest and the last few are the smallest (Table 2).
More specifically, in females, the first GLG is the widest averaging 509 µm, theTABLE 2. SUMMARY OF DESCRIPTIVE STATISTICS FOR TOTAL GLG WIDTHSMEASURED FROM THIN SECTIONS OF TEETH FROM TURSIOPS.
SIGNIFICANT DIFFERENCES DETERMINED USING A MANNWHITNEY RANK SUM TEST. MEASUREMENTS
IN MICROMETERS
GLG No.

2

3

4
5
6

7
8
9

10
11
12
13
14
15

Sex

N

Mean Width

Min.

Max.

F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
M
M
M

19
19
12

509
407
393
480
272
331
285
269
253
241
225
203
194
203
171
181
148
174
114
152
143
181
162
162
133
114
100

418
342
285
380
190
190
228
209
171
152
152
152
152
152
95
133
95
114
76
114
114
133
133
152
95
95
76

570
475
475
608
342
418
380
342
342
380
285
266
266
247
247
228
228
228
190
209
171
209
190
190
171
133
135

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

II

6
10
6
7
6
6
6
6
5
6
5
6
5
6
4
5
2
4
2
4
3
2
4

Significant
Differencesp<.005
p<.05
p<.05

HOHN

48

TABLE 3. SUMMARY OF DESCRIPTIVE STATISTICS FOR TRANSLUCENT LAYERWIDTH DIVIDED BY GLG WIDTH (=PERCENT TRANSLUCENT LAYER) FOR
EACH GLG MEASURED FROM THIN SECTIONS OF TEETH FROMTURSIOPS. SIGNIFICANT DIFFERENCES DETERMINED USINGA MANN-WHITNEY RANK SUM TEST. RESULTS
EXPRESSED AS PERCENTS
GLG No.

2
3
4
5
6
7
8
9
10
11

12
13
14
15

Sex

N

Mean Width-%

F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
F
M
M
M
M

19
19
10
11
6
9
6
6
6
6
6
6
5
6
5
6
5
6
4
6
2
4
2
4
3
2
4

9
10
15
14
39
23
40
33
41
41
48
41
48
45
50
49
57
48
57
45
73
44
71

52
51
47
50

Min.

Max.

4
4
4
18
5
17
13
22
10
33
14
38
36
33
23
40
33
50
27
67
27
70
38
50
43
50

17
14
33
32
67
50
60
50
56
75
36
56
58
50
60
57
71
67
67
56
78
57
71
63
52
51
51

Significant
Differences

p<.10

p<.10
p<.05
p<.05

second is smaller at 393 µm, with subsequent GLGs decreasing in width. An exception is a slight increase in size at GLGs 11 and 12 which might be an artifactof small sample sizes (N=2). In males, the trend is similar except that the second
GLG, which is 480 µm, is larger than the first, which is 407 µm. The third GLG
is smaller than the first and subsequent GLGs follow the same pattern as in theteeth of females. Again, there is a slight increase in size at GLG 11. Measurements of the widths of GLGs I, 2 and 3 are statistically significantly different between males and females (Table 2).
The width of the translucent layer follows the opposite pattern. GLGs set
down in older animals have wider translucent layers or the width of the translucent layer to the entire GLG (percent translucent layer) increases (Table 3). In
females there is a leveling off of percent translucent layer at GLGs 6 through 8,
then an increase for subsequent GLGs. In males, the percent translucent layer
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

49

AGE OF BOTTLENOSE DOLPHIN

increases initially, then remains fairly constant after GLG 4. This gives GLGs in
the teeth of male Tursiops a more even appearance in size and spacing, which isespecially apparent in SEM micrographs (Plate I, Fig. 1).
The translucent layer widths between females and males are statistically significantly different at GLGs 1, 3, 6, and 12. The percent translucent layer is significantly different between females and males at GLGs 3, 10, 11, and 12 (Table 3).
There are no measurements for females beyond GLG 12.
80
(')

(')

70
60
f-

(')

50

(')

zw

(')

...

~ ...

(')

......

......

...

...

Cl(')@ ...

~ 40
w

...

a..

30
20
10
0

~

o 1 2 3 4 5 6 7 8 91011121314151617
GLG NUMBER

Fig. 3. Average percent translucent layer for each GLG.
triangles are males.

Circles are females,

Last GLG
A plot of percent growth of the last layer against time of death for 28 female
and male Tursiops shows most of the points to set roughly on a line representing
the expected growth of the current GLG if the deposition of dentine is constant andthe new GLG begins in late January or early February (Fig. 4, Table 4 ). For thecluster of 14 points which occurs during February and March, with four additional
points in May, the extent of growth of the GLGs increases proportionally with timealong this line. Some of the points which do not fit this line fall on or close to another line representing the expected tooth growth of animals whose new GLG
begins in September. However, there are only six specimens representing thisgroup.
In most cases the last layer is opaque (Table 5 ). The translucent laye~ borders the pulp cavity in four of the specimens, and one of these is a translucent accessory layer and not a GLG boundary layer. Two of the GLG translucent layers
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

HOHN

50

100
/

90
80

/

b.

/
/

:::c

/

/

/

/

6

/

70

/

6

f-

s0 60

A

f-

/

a:
~ 50

/

/

(!)

/

(!)

/

/
/

/

zUJ 40

/

(.)

a: 30
UJ

(!)

a..

20
/

10
0

/

/

/

/

/

/
/

1

2

3

4

5

6

7

8

9

/

10 11 12MONTH

Fig. 4. Scatterplot of the percent growth of the last GLG in teeth of young Tursiops
on approximate date of death. Percent growth calculated for each animal from
actual width of the last layer divided by the average total width of the GLG. So]jd
line presents expected growth of the GLG throughout the year if the GLG begins
in lateJan.-early Feb. and grows at a constant rate. Hatched line represents thesame for GLGs which begin in September. Circles are females, triangles are
males. Hollow symbols indicate an opaque last layer, solid symbols represent atranslucent last layer.

occur in late January to early February and one occurs in September. The accessory layer that falls in mid-March is an animal whose dentinal growth pattern falls
on the line for GLGs which begin in the fall.

Non-GLG Layered Structures
In addition to GLGs three layered structures can be differentiated in the teethof Tursiops. Incremental layers are relatively evenly spaced layers which are foundthroughout the GLGs and are most easily seen in SEM micrographs of etched sections. Accessory layers are layers of opposite mineral density that would be expected within a GLG with an even mineral density. The third structure is similar to an accessory layer because it appears in a layer of opposite mineral densityof the dentine adjacent to it.
Incremental layers could be counted and measured from some of the SEM
micrographs (Plate I, Fig. 2). The average number of incremental layers per GLG
is 11.8 for three GLGs from 39 specimens (Table 5 ). Of the three GLGs in which
incremental layers could fairly consistently be counted, GLG 2 was the easiest for
counting. Incremental layers are rarely visible in the compressed GLGs set down
Sci. Rep. Whales Res. Inst.,

No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

51

TABLE 4. PERCENT GROWTH OF THE LAST FORMED GLG. GROWTH OF THE
LAST GLG AND TIME OF YEAR OF DEATH FOR SOME TURSIOPS MALES
AND FEMALES. PERCENT LAST LAYER CALCULATED FROMEXPECTED AVERAGE SIZE OF THE FULLY FORMED GLG.
OPTICAL DENSITY OF THE DENTINE BORDERING THE
PULP CAVITY IS BASED ON THIN SECTIONSUSING TRANSMITTED LIGHT
Catalogue
No.
Females504565504590504403CWP094
SEAN3331
504539504550504592504399504583395179504528504549Males
504578
JGM401504536504553504567504218395790504535504561504591504290504122504551504765CWP084504291504313% Growth
Last GLG

Approx. Dateof Death

OpticalDensity

2
2
2
2
2
2
2

31
26
26
37
50
56
0
14
28
21
63
0
21

late Feb
mid-March
15 May22 Maymid-Auglate Dec
early Feb
30 March
15 Mayearly Mar
4 Nov
early Dec
mid-Feb

opaqueopaqueopaqueopaqueopaqueopaquetranslucent
opaqueopaqueopaqueopaquetranslucent
opaque005480late Feb
14 Dec21 Janmid-Feblate Feb
I March
22 Mayearly Janearly Marearly Mar
mid-June
21 Sept
11 Feb
14 Marlate Mar
27 June3 Septtranslucent*opaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaqueopaquetranslucent

No. ofComplete GLGs

9
21
17
25
92
2
2
2
2
3
3
3
3
3

77
25
35
60
13
13
44
71
0

* translucent accessory layer.

in the teeth of "old" animals, e.g., beyond GLG 10, in etched sections. Even in
the first few GLGs incremental layers were not always clear enough to count. On
the etched surface of the tooth, they were most clear on the "slopes" rather thanon the top of a ridge, where one prominent very wide increment often turned out
to be two, or in the grooves, where it is was "dark". The incremental layers havethe same three-dimensional pattern as GLGs and are only visible when there is acontrast between the ridges and grooves of adjacent increments.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

52

HOHN
TABLE 5. NUMBER ·OF INCREMENTAL LAYERS PER GLG
IN TURSIOPS DENTINE
Catalogue No.
29147250412229143129140329140212277
291462CWP088

GLG l
12-13
9
12

191456504534504864504726291498291466395430395179504561
JGM39929142614

Means
Std. dev.

GLG 2
12
13

GLG 3
12

>3 GLGs
10-11

11

13
10

8-9
11-12
9

12
13
12

14
12-13

11
11

11
11
9
12
11

11

12
11-12
10
10
11-12

10-12
10

12
11
11

12.2
1.6

15

11

Summary
11.8
1.2

11.3
l. l

10.8
1.2

The widths of the incremental layers varied slightly (Table 6). Their mean
width in GLG 1 was 26 µm and 23 µm, for ridges and grooves, respectively, 28 µm
and 26 µm in GLG 2, 27 µm and 24 µm in GLG 3, and 23 µm and 20 µm for measurements made from GLGs later than three. It appears, in general, that increments in the grooves are smaller than those on the ridges in the same GLG and thatthe increments become smaller with successive GLGs.
Conversely, accessory layers tend to be variable in position and intensity, but
are usually thin translucent layers or lines within the opaque layer of the GLG.
In addition, in each of the first two GLGs there is an especially wide, prominent
layer about halfway through the GLG (Plate II, Fig. 1). In the first GLG, thisaccessory layer occurs an average of 50% through the GLG in females and 64% of
the width of the GLG in males. It occurs approximately in the middle of thesecond GLG in females and males. In some teeth these accessory layers are more
conspicuous than the GLG boundary layer. This is particularly true since in thefirst two GLGs the translucent boundary layer is very narrow. In GLGs beyond
number three, accessory layers become less frequent and the center, wide accessory
layer is not as pronounced. Accessory layers are not found in the compressed GLGs
set down in old animals.
A third non-GLG layered structure might also be called an accessory layer.
These layers occur adjacent to any accessory or GLG boundary layer as very inSci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

53

TABLE 6. WIDTHS OF INCREMENTAL LAYERS IN TURSIOPS DENTINEMEASURED FROM SEM MICROGRAPHS OF ETCHED SECTIONS.
MEASUREMENTS ARE SEPARATED BY THEIR LOCATIONWITHIN A GLG AND BY GLG NUMBER.
MEASUREMENTS IN MICROMETERS
Cata!.
No.

29147250412229143129140329140212277
291462

GLG 1

GLG 2

GLG 3

Ridge

GrooveRidge

GrooveRidge

Groove

Ridge

38.8

35.4

34.6

25.4

26.6

20.3

29.8

20.0
25.0

26.0

28.9
24.0

36.3

23.9

34.5

31.8
27.5

25.8
32.0
29.3

32.5

25.0
20.0
30.0

25.0
32.5

Groove

17.5
22.8

22.5

31.5

30.8
16.8
20.3

CWP088291456504534504864504726291498291475291466395179504561
JGM399504532291426395430>3 GLGs

22.1
22.5

18.9
15.0

19.8
20.3
18.4
31.0

14.3

20.2
35.7
15.2
22.8

14.4
47.7
29.9

31.3

16.3

28.6
18.0

40.0
15.1

11.9

20.0
28.6

17 .1
16.7

28.6
29.2
29.8

20.0

26.6

28.0

27.8
22.5

23.9
7 .0

23.0
4.7

20.0
SummaryMeans
26.2
Std. Dev.
7.5
Overall mean
Std. Dev.

23.4
8.4

27.6
8.7

26.2
5.7

26.6
9.2

20.2

26.1
7.0

tense narrow bands of the opposite mineral density as the structure they abutt.
Most often, this layer is opaque and follows a translucent layer. It is very noticeable following the neonatal line, the wide central accessory layer, and some of theirregular accessory layers throughout the GLGs. When this structure occurs bythin translucent boundary layers, it is sometimes more prominent than the translucent layer so more easily used as the boundary layer (Plate II, Fig. 2).

Sexual Dimorphism
Measurements of four of the five variables specifically tested for possible sexual dimorphism similar to that found by van Utrecht (1969) proved not to be significantly different (Table 7). The difference in the fifth variable, neonatal line
width, was highly significant (p<.005) using a t-test with males having a wider
neonatal line than females.
Sci. Rep. Whales Res. Inst .•No. 32, 1980

54

HOHN
TABLE 7.

SUMMARY OF MEASUREMENTS FOR POSSIBLE SEXUALDIMORPHISMS IN THE TEETH OF TURSIOPS.
MEASUREMENTS IN MICROMETERS

Variable
Extent neonatal line extends
beyond enamel, convex side*
Extent neonatal line extends
beyond enamel, concave side*
Width of prenatal zone, convex
side*
Width of prenatal zone, concave
side*
Neonatal line width convex
side**

Sex

N

Mean

S.E.

F
M
F
M
F
M
F
M
F
M

13
18

418.0
471.8
429.2

64.2
52.5
54.4

405.3

53.3

58.5

4.4

54.4

4.3

21

54.6
48.1
27.0

5.2
4.6
0.8

22

37.3

1.3

17
18
13
18
16

18

* Not significantly different using Student's t-test.
** Significant at p< .005.

DISCUSSION

Age and Growth
The growth rate of Tursiops is similar to that of many other odontocetes.
During its first year, an average western North Atlantic Tursiops increases its lengthby 53%, approximately the same increase found for the same age animals of Stenella attenuata (Perrin et al., 1976), S. coeruleoalba (Kasuya, 1972, 1976), Globicephalamelaena (Sergeant, 1962), Tursiops from Florida (Sergeant et al., 1973), and Tursiops
from South Africa (Ross, 1977). The rate of growth decreased during the second
year of life, averaging only a 10% increase in total length in these Tursiops and an
average of 10 to 15% in the other species mentioned above. After three GLGs thegrowth rate slows cbnsiderably.
Cetaceans have been described as having high rates of growth while they areyoung (Bryden, 1972). However, there is a great deal of variability in total lengths
of individuals in any age class. In S. longirostris, animals with one GLG range fromabout 100 cm to 135 cm in total length, those with two GLGs range from 110 to145 cm, with equivalently large variation in older animals (Perrin et al., 1977). In
pilot whales, G. melaena, neonates range from 165 to 195 cm in total length (Sergeant, 1962). A sample of harbor porpoises from the Bay of Fundy ranged from75 to 105 cm at birth, 105 to 130 cm at one year, 118 to 135 cm at two years, 125
to 145 cm at three years, again continuing this variation in length within each age
category for older animals (Gaskin and Blair, 1977). The large variability andoverlap of different aged animals illustrates that, although it is useful to construct
growth curves and use mean total lengths for examining growth rates, it is not reliable to use total length to determine the age of an individual.
In the western North Atlantic Tursiops an especially large range in total length
exists in each age class. This may be due to strandings of individuals from two
different population of Tursiops, coastal and offshore, where the offshore animals
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

55

seem to be larger than those found along the coast CJ. G. Mead, unpub. data).
At this time, however, it is not possible to differentiate to which population a young
stranded animal belonged, so all specimens less than 280 cm have been included.
Differences in adult total length or rate of growth between males and females
have been found in some cetaceans. When it occurs, generally males are larger
than females as adults in odontocetes (e.g. pilot whales and sperm whales), whilein mysticetes males are smaller than females as adults (e.g. humpbacks and fin
whales) (Bryden, 1972). But delphinids generally have not been found to be dimorphic in adult total length (True, 1889; Sergeant et al., 1973). The results fromthis study seem to support this.
Two studies have been published on the growth rate of wild Tursiops. Sergeant et al. (1973) looked at Tursiops from Florida waters. Although they reported
birth to occur at 100 cm, they present no data for neonates. The growth curve,
based on 22 males and 24 females, is similar to that of western North Atlantic
Tursiops but with younger animals (less than five GLGs) apparently smaller in
Florida. The apparent difference between the two groups may be due to differences in our definition of GLGs. The asymtotic length of males from Florida wasfound to be 270 cm and that of females to be 250 cm. The coastal Tursiops in thisstudy appear to have the same asymptotic length for males and females at 250 to
260 cm. Ross (1977) gives some biology of T. aduncas from South African waters.
The age of birth ranged from about 84 cm to 112 cm. Females reached sexual
maturity at a smaller length than males. The largest female was 252 cm and thelargest male 254 cm which makes them smaller than the western North Atlantic
Tursiops. Although the Tursiops from Florida waters might be the same type as
those from further north along the coast, those from Africa are probably not.

GLG Widths
As a dolphin tooth grows and deposits more dentine, the pulp cavity becomesincreasingly smaller until it finally occludes and no more dentine deposition canoccur. Correspondingly, as the pulp cavity becomes smaller, the GLGs become
narrower. This decrease in GLG width could be solely the result of the new forming GLG being compressed into a smaller pulp area. If this is the case then each
GLG would be a little smaller than its preceding GLG and a plot of the relationship between GLG width and number would be approximately a straight line witha negative slope. If this relationship follows a different pattern then it would suggest that there are other factors influencing the deposition or mineralization ofdentine.
There are some general patterns that can be found in a plot of average GLG
width against GLG number that suggest that physiological factors affected by theage or sex of the animals are important in GLG growth. These patterns can bevisualized in Fig. 2. First, there are significant differences between males andfemales in the widths of the first two or three GLGs. It is particularly interestingthat the second GLG is, on the average, wider than the first GLG in teeth frommales, and that the third GLG decreases so that it is narrower than the first. SecSci. Rep. Whales Res. Inst.,
No. 32, 1980

56

HOHN

ondly, the changes in width of the first three GLGs is large, but subsequent GLGs
show a marked decrease in this rate, i.e., GLGs following number three are notmuch narrower than their adjacent preceding GLG. This appears to be an affectof age of the animals since it occurs in females and males. Again it is interestingthat this abrupt decrease in GLG deposition rate occurs at the same time that thegrowth curve of Tursiops (Fig. 1) shows a noticeable decrease in rate of growth.
Thirdly, the average width of each GLG is larger in females than in males from
GLGs four to six and smaller in GLGs which follow. The effect is an almost constant decrease in width of GLGs four through ten in females. In males, the rate ofchange in width of GLGs appears smaller than in females for GLGs six through ten.
In an etched section of tooth, these GLGs appear evenly spaced and sized acrossthe surface and almost can be considered diagnostic to determine teeth from males.
Similarly, the characteristic constant decrease in size of GLGs in teeth from females
is apparent in etched sections. Perrin et al. (1977) plotted the percent decrease inwidth from one GLG to its adjacent GLG in the spinner dolphin beginning at GLG
3 and continuing to GLG 16. They found that each GLG average more than 95%
of the width of the preceding GLG. They did not consider females and males separately, which in Tursiops teeth gives different results, as discussed above. A progressive decrease in width of GLGs has also been described from the harbor porpoise (Nielsen, 1972; Gaskin and Blair, 1977), striped dolphin (Kasuya, 1972), andthe pilot whale (Sergeant, 1962). Christensen (1973) found an initial decrease inbottlenose whales followed by constant thickness after the fourth GLG. Except for
Gaskin and Blair (1977), measurements of widths were not given, nor were specificdifferences by sex or age noted. The mean widths of GLGs given by Gaskin andBlair (1977) show that GLGs are wider in teeth from female harbor porpoises thanthose from males.
The translucent layer can also be used as an indicator of physiologicalchanges affecting GLGs. The absolute value of the width of the translucent layer
is probably not an important parameter by itself, except to help determine the timespan over which it is deposited, because it is dependent on the GLG number andwidth. The percent translucent layer is a more useful quantity. As with GLG
width, the trend in percent translucent layer is different in females and males although significant differences occur only in GLGs 3 and 10 through 12. In females, the percent translucent layer increases almost continuously with age.
Beyond GLG 10 more than half of the GLG consists of the translucent layer, reaching about 70%. This trend appears as an initial rapid increase in percent translucent layer which levels almost as a plateau (between GLGs 3 through 8) then increases rapidly again after GLG 8. This is noticeably different than males where
an initial rapid increase in percent translucent layer leads to a nearly constant level,with some fluctuation. The translucent layer comprises only about 50% of the
GLG after GLG 8. The change in percent translucent layer around GLG 8
through 10 in females and males may be related to physiological changes associated with the onset of sexual maturity, since this seems to be approximately the age
at which the animals become sexually mature (Harrison, 1969; Ridgway, 1972).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

57

The changes at GLGs 3 to 4 may be influenced by the decreasing growth rate atthat age. The large percent translucent layer in females beyond age ten can be
speculated about with even less certainty. The most obvious explanation since
there are such large differences between males and females would be that the wide
translucent layer, which is hypomineralized (Hohn, in press), is the result of a calcium drain caused by reproduction. At this time, there is no direct evidence forthis. Gaskin and Blair (1977) noticed a progressive increase in proportional thickness of the translucent layer with age in harbor porpoises but only in females, sothey attributed it to calcium mobilization. They constructed a regression line
through a scatterplot of the proportion of opaque layer to translucent layer but did
not mention specific differences at any age. However, their results, along withmine, indicate that percent translucent layer is worth examining in other species
for possible dimorphism and explanation for the formation of the layers.
Last GLG
Most of the strandings of Tursiops occurs during February and March. Since
calving also occurs during this season, it should be about this time when the neonatal line appears in the teeth. If the deposition of dentine is fairly constant, animals
born in the late winter to early spring would have completed each GLG during thatseason in successive years and then started another GLG. Each month more of
the new GLG would have accumulated following a hypothetical line representing
constant growth by percent GLG formed throughout the year, one twelfth or 8%monthly, as in Fig. 4. Most of the 28 animals examined for percent growth of thelast GLG follow this hypothetical line, at least during the spring of the year whenmost of the animals strand. However, this line begins in January or early February, earlier than when neonates are generally found. By late February or March,
10 to 20% of the new GLG has already formed, the amount that would be expected
at a constant deposition rate of dentine with the new GLG beginning in January.
This would suggest that the end of the previous GLG, which is the translucent layer,
occurs in December or January. Scatter around this line is probably due to individual variation in time of birth and actual widths of GLGs, and possibly to abnormal physiological states of the animals before they strand.
Tursiops may have two seasons of parity: one in the spring and another in thefall (Townsend, 1914; Harrison, 1969; Ridgway, 1972; Ross, 1977). In particular,
Townsend (1914) believed that North Atlantic Ocean Tursiops give birth during
both seasons. Ross (1977) has found stranded neonates in the fall and spring whichsuggests more than one or an extended breeding season. But neonates have notbeen found through the MMSP during the fall, even though many are picked up
during the spring. However, ifthe growth of the tooth can be used as an indicatorof season of birth, i.e., animals born in the spring have formed one GLG the following spring as previously discussed, then Tursiops which have formed 50% of a
GLG in the spring must have started that GLG during the fall. Similarly, ananimal whose last GLG ends in the fall, probably also began deposition of GLGs
during the fall. A hypothetical line drawn to represent the expected growth of teSci. Rep. Whales Res. Inst.,
No. 32, 1980

58

HOHN

eth which begin GLGs in the fall should parallel the equivalent line for animals
whose GLGs begin in the spring, but off-set by approximately six months. Thishypothetical line, represented in Fig. 2, has several points which fall on or close toit. This would suggest that these animals were also born in the fall rather than in
the spring as we would have anticipated based on stranding records. This may
provide evidence to support Townsend's (1914) idea of two seasons of calving for
Tursiops in the North Atlantic Ocean.
Although growth layers in teeth and bone have been used for about 30 years
for age determination, there have been only speculative suggestions as to the causeof the rhythmic deposition of the layers. The environmental or endocrinologicalmechanisms influencing or regulating the mineralization pattern in hard tissue is
unknown. In several species of odontocetes, the optical or mineral density of the
GLG layer bordering the pulp cavity when an animal dies has been used as an indicator of the physiological or nutritional state of the animal. Sergeant (1959)
found the "clear zone" (translucent layer) to begin in February and occur throughApril in captive Tursiops from Florida. Sergeant et al. (1973) said they could not
determine the density of the last layer in mostly wild Tursiops from Florida basedon their sample size (N=62). Sergeant (1962) found the opaque zone to occur adjacent to the pulp cavity in pilot whales, Globicephala melaena, from Canadian waters
caught in the summer. In a mass stranding of pilot whales, G. macrorhynchus, in South
Carolina during mid-October, the opaque layer bordered the pulp cavity (unpub.
data). Nishiwaki and Yagi (1954) found that the well stained (=opaque) layers
occur in December and May through June in S. coeruleoalba. Similarly, the opaquelayer borders the pulp cavity in June through February in harbor porpoises fromthe Bay of Fundy (Gaskin and Blair, 1977), in the summer in Baird's beaked whales
from the North Pacific (Kasuya, 1977), in May and June in bottlenose whales fromthe North Atlantic (Christensen, 1973), and in June through November in dugongs
from the equatorial and North Pacific (Kasuya and Nishiwaki, 1978). In summary, the opaque layer appears to border the pulp cavity at least during the summer months, and usually longer, in most species. Conversely, the translucent layer
is more often at that point during the winter or early spring. In Tursiops, the translucent layers, as accessory layers or GLG boundary layers, are deposited in the fall
(September, N=l), and in late January, early February, or March (N=3). However, all the animals examined were young which is when the translucent layer isvery narrow. As males and females age, a higher proportion of each layer becomestranslucent, so the time of deposition of each layer of a GLG would depend on theage of the animal, at least in Tursiops. This, again, assumes that the dentine continues to be deposited at a constant rate and only the mineralization pattern changes. The GLG number at which previous researchers determined the optical or
mineral density of the layer bordering the pulp cavity, or changes in the relative
amount of translucent dentine, has not been mentioned. The collection of enoughdata of this kind may help us to understand the cause of layering.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

59

Non-GLG Layered Structures
Incremental layers. It is difficult to count incremental layers from SEM micrographs because the small mineral changes throughout an increment and between
increments does not always produce enough contrast in etched sections to make individual increments clear (Plate III). In addition, increments are difficult to seeon the "back side" of a ridge or in a groove where it is "dark" because fewer electrons reach the collecting plate. The effect is probably that counts are slight underestimates of actual numbers of incremental layers.
Partially for the same reasons, it may not be accurate to measure widths of incremental layers from etched sections. The etching process produces the ridge andgroove pattern in GLGs and in incremental layers, so there is no longer a flat surface. This is compounded by the tilting of the sections in the SEM chamber. Although the quantitative effect of these factors is unknown, the average number ofincrements per GLG (12) multiplied by the average width of the increments (26µm) is not equivalent to the average width of the first three GLGs measured fromthin sections (approximately 420 pm). Measurements are probably an underestimate of actual sizes of increments. SEM of etched sections, however, seems toprovide the best way to visualize incremental layers.
The appearance of incremental layers in Tursiops dentine supports the idea of
Schour and others that dentine grows or is mineralized in spurts or increments.
The frequency of approximately 12 increments in one annular layer or GLG suggests that this sub-annual growth is similar to that described in dugongs (Kasuya
and Nishiwaki, 1978), Baird's beaked whale (Kasuya, 1977), and dolphins of thegenus Stenella (Myrick, in press). However, the width of the increments has notbeen determined for those species. The average size (26 µm) of incremental layers
in Tursiops dentine seems much too large to represent daily von Ebner's lines of 5
pm width described by Krauss and Jordan (1965) and Newman and Poole (1974)
in human teeth, or von Ebner's lines in pig dentine (Yilmaz, Newman, and Poole,1977). If incremental lines in Tursiops are approximately monthly, daily increments would have to average 0.87 µm, measured from SEM micrographs. Myrick(in press) has found daily increments in dolphin dentine, but has not determined
the width of either these von Ebner's lines or the "monthly" growth increments.
Schour and Hoffman (1939) measured the "calcification" rhythm in 17 species ofvertebrates and found it to recur at intervals of 16 µm (no time interval was mentioned). They were counting accentuations (light or more calcified areas) whichalternated with dark areas. It is possible that "monthly" increments in Tursiops,
which are the result of mineral differences, are similar to the pattern found in othervertebrates by Schour and Hoffman (1939).
One of two basic assumptions seems to be made when considering the deposition or mineralization of dentine. The first presumes the increments are timeregulated by some extrinsic or intrinsic factor so that the common denominator isthe number of increments set down during a given period of time. The second
assumption is that these processes continue at a constant rate regardless of the age
or the species of the animals. The latter would seems to be supported by SchourSci. Rep. Whales Res. Inst.,
No. 32, 1980

60

HOHN

and Hoffman's (1939) observations of the 16 µm calcification rhythm and researchers looking at constant sizes ofvon Ebner's lines (Krauss and Jordon, 1965; Newman
and Poole, 1974). However, the authors do not specify the age of the dentine
where the measurements were made, e.g., immediately subjacent to the enamel orseveral years growth away from the enamel. Nor do they mention making a seriesof measurements throughout each tooth, except over short periods of time such asdays or weeks. Although my measurements of incremental layers are subject toerror, as discussed previously, the trends suggest that the increments decrease insize in GLGs set down later in an animal's life. Increments in GLGs beyond
number three are smaller than those in the first three GLGs. This may be an artifact of etched sections. However, in order for the number of increments to remain
the same in all of the GLGs, the increments must become narrower as the GLGs
become narrower; again with the assumption that the number of incremental layers
is relatively constant, which seems to be more supported by the data from Tursiops
teeth.
The assumption of constant size of increments also seems to be disputed by
the differences in width of incremental layers on the ridges and grooves in etched
sections. Increments in the grooves measure, on average, smaller than incrementson the ridges and slopes of .the GLGs. This size difference may be a result of thecollapse of the tissue when the mineral is removed or it may be a real difference inwidths of increments in the hypomineralized and hypermineralized parts of the
GLG. This should be checked in untreated dentine, possibly in thin sections using
a petrographic microscope (Myrick, in press).
It is tenable that the mineralization or deposition of dentine could be regulated by monthly or lunar factors, that this produces the relatively constant numberof increments per GLG in Tursiops teeth and possibly all species, that the size ofthe increments changes progressively with the age of the animal and possibly between the hypo- and hypermineralized layers of the GLGs, and that the incremental layers can be used to gain more information about the biology of species and thegrowth of mineralized tissue. However, this must be measured by direct marking
of individuals, e.g., tetracycline, or by the examination of many more species before any conclusions are drawn.
Accessory layers. There appears to be two kinds of accessory layers as they havebeen described formally or referred to in the literature. The first are the narrow
accessory layers which appear irregularly in GLGs. These are approximately thesame size as incremental layers and can be distinguished from incremental layers
only because their mineral density, seen as optical density, differs appreciably fromthat of the GLG layer in which they occur. The second kind are the very prominent, wider than incremental layer accessory layers which occur regularly, approximately in the center of the GLG. It is undoubtedly these prominent accessory layers
which are responsible for the debate about number of GLGs set down annually inodontocete teeth. An unexperienced person would almost assuredly count theseregular accessory layers as GLGs. For example, Leatherwood et al. (1978) counted
five GLGs in thin sections of teeth from a young Tursiops (USNM 504122). In
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

61

the same animal I counted a little more than two GLGs (Plate 5). The SEM micrograph shows only two GLGs (although the first prominent ridge is an accessory
layer - the first translucent layer is hardly visible). Similarly all of their countsof GLGs from seven Tursiops used in both studies are in disagreement with mine,with their counts from the teeth of young animals doubling mine. Kleinenberg
and Klevezal (from Klevezal and Kleinenberg, 1967) described an annual deposition of two GLGs in the teeth of the Black Sea dolphin, Delphinus delphis, which
they later (1967) attributed to the presence of this accessory layer. In general,they agreed that GLGs are annual but this prominent center accessory layer often
gives the impression that two GLGs are deposited.
Myrick (in press) refers to incremental layers in Stenella teeth as accessory layers. It seems that incremental layers are visible due to their mineralization cycle
within GLGs. If this cycle is subject to extrinsic or intrinsic influences then incremental layers will be more obvious within a GLG when the expected mineral density is disrupted. This disruption would make the incremental layer appear as oneof the narrow, irregular accessory layers. In the first two GLGs where the translucent layer is very narrow, these accessory layers would and do make it difficult
to determine where the GLG ends. However, incremental layers by themselves
do not usually interfere in the process of counting GLGs in Tursiops teeth, especiallyusing SEM.
Regardless of the kind of accessory layer, accessory layers make counting GLGsvery confusing in the first few GLGs. A person experienced in "reading" odontocete teeth can probably estimate very close to the actual number of GLGs in a tooth
section, but identifying the exact end of a GLG becomes very difficult in someteeth. There is also a great deal of variability between animals. Accurate age determination of some species of odontocetes, e.g. Tursiops, depends on experience,from looking at many teeth from all ages of the animals to accurately identify accessory layers before trying to count GLGs.
Small scale mineral changes. The narrow opaque accessory-type layers which
follow translucent layers appear to be the result of abrupt small-scale changes in thedentine. Irving and Weinmann ( 1948) described a similar occurrence in rat incisors.
They injected rats with strontium to observe the effects on calcification in the teeth
and found that the strontium caused a hypocalcified layer (16 µm wide) to occur.
Immediately following this layer, a very evident narrow "calciotraumatic" line wasfound which sharply demarcated the hypocalcified dentine from the normal, calcified dentine. They attributed this line to be caused by a shock to calcium metabolism in the rat by the strontium. The same effect was found in rats after administration of calciferol or parathyroid hormone (Schour and Ham, 1934; Schouret al., 1934), orimmediately following parathyroidectomy (Schour et al., 1937), where
the parathyroid helps regulate mineralization processes. In addition, Kronfeld andSchour (1939) found the calciotraumatic line to occur following the neonatal line.
It may be this same calciotraumatic line that is present in thin sections of Tursiops
teeth following the neonatal line and other translucent zones.
There has been some question about the mineral density of the narrow layers
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

62

HOHN

in odontocete teeth, for example, the neonatal line. The consensus is that they aretranslucent and hypomineralized. But Nielsen (1972), Klevezal and Kleinenberg(1967), and Kasuya (1976) have suggested that the narrow layers are translucent but
hypermineralized for some species. The wide layers are then relatively hypomineralized, so the relationship between mineral and optical densities is different from thatof other odontocetes. Because of this, Nielsen (1972) has suggested that opticaldensity cannot be used as an indicator of mineral density. However, it may bethat where the translucent layer is very narrow, the opaque "calciotraumatic" line
is more apparent and is considered the layer. In some tooth sections of Tursiops it
is easier to use this opaque line than the preceding translucent layer to follow a
GLG down the extent of the tooth. However, the neonatal is still considered to betranslucent and hypomineralized and subsequent boundary layers are translucent
and hypomineralized. The calciotraumatic line needs more examination for its
occurrence and effect in odontocete teeth.

Sexual Dimorphisms
The sexually dimorphic trait found by van Utrecht (1969), i.e. the greater
extent of the neonatal line in males, in teeth from 20 harbor porpoises, Phocoena
phocoena, is not significantly different in the teeth of male and female Tursiops. Van
Utrecht also mentioned that the same trait was applicable to Lagenorhynchus albirostris, a delphinid, but this was based on only three females and three males. Teethof species from the family Phocoenidae are considerably different from those of thefamily Delphinidae. Instead of the nested "cone" appearance of GLGs in Tursiops teeth, the GLGs in Phocoena are bulbous in the crown or spatulate end, thencontinue in the narrower root parallel to the long axis, as in the handle of a spatula.
The difference in growth between phocoenid teeth and delphinid teeth presumably
allows for any dimorphic growth of the neonatal line relative to the top of the cement in Phocoena but not in Tursiops.
The second trait examined for possible differences between sexes of Tursiops
seems related to the first. If the neonatal line was to extend further down the rootof the tooth in male Tursiops as it does in male Phocoena, it might be because there
was a greater amount of prenatal dentine in males. Having more prenatal dentine
could have suggested that the neonatal line was deposited at a later time in males
or that the tooth began development earlier. But neither trait was significant soshould not be used to identify an animal of unknown sex in Tursiops.
The greater extent of the neonatal line could also be related to the widthof the neonatal line. If the measurements were made from the outer edge of theneonatal line, a wider neonatal line would extend its length if the deposition of theneonatal line was initiated at the same time in males and females. In the case of
Tursiops, the width of the neonatal line is significantly different in males and females. However, the greater neonatal line width in males is coupled with insignificant differences in either the extent of the neonatal line or width of the prenatalzone. This is probably because the neonatal line is very narrow, especially relative to its length, and the 10 µm mean difference in this width between males andSci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

63

females does not significantly alter the overall measurement of the extent of the neonatal line. In addition, it is very difficult to accurately measure the neonatal line
width because it is so small and, although not difficult to identify, its boundaries
are not always clear. Even though the width of the neonatal line proved to be asignificantly different sexually dimorphic trait, I would not recommend that it beused as the sole identifier of the sex of an unknown specimen of Tursiops.
ACKNOWLEDGMENTS
A great deal of help came from the staff at the National Museum of Natural
History (NMNH). Mary Jacque Mann of the SEM lab was invaluable for her
skill with the SEM. Victor Krantz, NMNH photo lab, took the photomicrographs.
Charley Potter helped gather specimens and read parts of the draft. Eugenie
Clark, University of Maryland, gave me continuous support and offered suggestions on the manuscript. James G. Mead, curator of marine mammals, NMNH,
gave me the use of research materials and equipment, data he had been collecting
for many years, financial support as the research required, and discussed many aspects of this work with me as it progressed. To him I am especially grateful.
REFERENCES
BEST, P. B. 1970. The sperm whale off the west coast of South Africa. 5. Age, growth, and mortality. Invest!. Rep. Fish. Mar. Biol. Surv. Div. S. Africa 79: 1-27.
BEST, P. B. 1976. Tetracycline marking and the rate of growth layer formation in the teeth of a dolphin,
Lagenorhynchus obscurus. S. Afr. ]. Sci. 72: 216-218.
BRODIE, P. F. 1969. Mandibular layering in Delphinapterus leucas and age determination. Nature 221: 956-

958.
BRYDEN, M. M. 1972. Growth and development of marine mammals. pp. 1-80. In: R.J. Harrison (ed.)
Functional anatomy ef marine mammals. Vol. I. Academic Press, London. 451 pp.
CHRISTENSEN, I. 1973. Age determination, age distribution and growth of bottlenose whales, Hyperoodon
ampullatus (Forster), in the Labrador Sea. Norw. ]. Zoo/. 21: 331-340.
GAMBELL, R. 1977. Dentinal layer formation in sperm whale teeth. pp. 583-590. In: M. Angel (ed.)
A Voyage of Discovery. Pergamon Press, Oxford, 696 pp.
GAMBELL, R. and C. GRZEGORZEWSKA. 1967. The rate of lamina formation in sperm whale teeth. Norsk
Hvalfangsttid. 56 (6): 117-121.
GASKIN, D. E. and B. A. BLAIR, 1977. Age determination of harbour porpoises, Phocoena phocoena, in thewestern North Atlantic. Canadian]. Zoo/. 55 (1): 18-30.
GUREVICH, V. and B. STEWART, in press. The use of tetracycline marking in age determination of Delphinus
de/phis. In: \'\I. F. Perrin and A. C. Myrick (eds.) Age determination of toothed cetaceans and sirenians. Spee. Issue 3. Iwc, Cambridge.
HARRISON, R.J. 1969. Reproduction and reproductive organs. pp. 253-348. In: H. T. Andersen (ed.)
The biology of marine mammals. Academic Press, N. Y., 511 pp.
HAY, K. in press. Age determination of the narwhal. Jn: W. F. Perrin and A. C. Myrick (eds.) Age
determmination of tooched cetaceans and sirenians. Spee. Issue 3. IWC, Cambridge.
HOHN, A. A. in press. Analysis of growth layers in the teeth of Tursiops truncatus using light microscopy, microradiography, and SEM. In: W. F. Perrin and A. C. Myrick (eds.) Age dermination of toothed
cetaceans and sirenians. Spee. Issue 3. IWC, Cambridge.
IRVING, J. T. and J.P. WEINMANN, 1948. Experimental studies in calcification, VI. Response of dentin ofSci. Rep. Whales Res. Inst.,
No. 32, 1980

64

HOHN

the rat incisor to injectioµs of strontium. J. Dent. Res. 27: 669-680.
KAsUYA, T. 1972. Growth and reproduction of Stene/la caeruleoalba based on the age determination by meansof dentinal growth layers. Sci. Rep. Whales Res. Inst. 24: 57-79.
KASUYA, T. 1976. Reconsideration of life history parameters of the spotted and striped dolphins based on
cementa! layers. Sci. Rep. Whales Res. Inst. 28: 73-106.
KASUYA, T. 1977. Age determination and growth of the Baird's beaked whale with a comment on feta!
growth rate. Sci. Rep. Whales Res. Inst. 29: 1-29.
KASUYA, T. and M. NISHIWAKI, 1978. On the age characteristics and anatomy of the tusk of Dugong dugon.
Sci. Rep. Whales Res. Inst. 30: 301-311.
KAsuYA. T, N. MIYAZAKI, and W. H. DAWBIN, 1974. Growth and reproduction of Stenella attenuata in thepacific coast of Japan. Sci. Rep. Whales Res. Inst. 26: 157-226.
KHuzIN, R. SH. 1961. Metodika opredeleniya vozrasta imaterialy po razmnozheniyu belukhi (Method ofage determination and data on the reproduction of the white whale). Nauchno-Tekh. Informatsionnyi
Byull. PINRO I (15): 58-60.
KIMURA, M. in press. Variability in dentinal layer counts (age estimates) by different observers on thetooth of a known age bottlenose dolphin, Tursiops truncatus. In: W. F. Perrin and A. C. Myrick (eds.)
Age determination of toothed cetaceans and sirenians. Spee. Issue 3. IWC, Cambridge.
KLEVEZAL, G. A. and S. E. KLEINENBERG, 1967. Opredelenie vostrata mlekopitayushchikh po sloistym
strukturam zubov i kosti. Izdatel'stvo Nauka, Moscow, 144 pp. [Trans!.] 1969. Age determination of
mammals from annual layers in teeth and bones. Israeli Prag.for Sci. Trans!., Jerusalem. 128 pp.
KRAUSS, B. S. and E. S. JORDAN, 1965. The human dentition before birth. Henry Kempton, London.
KRONFELD, T. and I. ScHOUR, 1939. Neonatal line hypoplasia. j. Amer. Dental Assoc. 26: 18-32.
LANKESTER, E. R. 1867. On the structure of the tooth in ,(iphius sowerbiensis (Micropteron sowerbiensis, Eschricht), and on some fossil cetacean teeth. Royal Microscopical Soc. Trans. XV: 55-64.
LAws, R. M. 1952. A new method of age determination in mammals. Nature 169 (4310): 972-973.
LAWS, R. M. 1953. A new method of age determination in mammals, with special reference to the elephantseal, Mirounga leonina Linn. Falkland Is. Dependencies Survey, Sci. Rep. 2: 1-11.
LEATHERWOOD, S., M. W. DEERMAN, and C. W. POTTER, 1978. Food and reproductive status of nine Tursiops truncatus from the northeastern United States coast. Cetology 28: 1-6.
MYRICK, A. C. in press. The use of the petrographic microscope in examination of ultrastucture in hardtissues in odontocetes. In: W. F. Perrin and A. C. Myrick (eds.). Age determination of toothed cetaceans and sirenians. Spee. Issue 3. IWC, Cambridge.
NEWMAN, H. N. and D.F.G. PoOLE, 1974. Observations with scanning and transmission electron microscopy on the structure of human surface enamel. Arch. Oral Biol. 19: 1135-1143.
NIELSEN, H. G. 1972. Age determination of the harbour porpoise Phocoena phocoena (Cetacea). Vidensk.
Meddr dansk naturh. Faren. 135: 61-84.
NrsmwAKI, M. and T. YAGI, 1953. On the age and growth of the teeth in a dolphin (Prodelphinus caeruleoalbus). Sci. Rep. Whales Res. Inst. 8: 133-146.
NrsHIWAKI, M. and T. YAGI, 1954. On the age determination method of the toothed whales by the studyof the tooth. Proc. Japanese Acad. 30 (5): 399-404.
NrsHIWAKI, M., H. TAKASHI, and S. 0HSUMI, 1958. Age study of the sperm whale based on reading of toothlamination. Sci. Rep. Whales Res. Inst. 13: 135-155.
OMURA, H., K. FUJINO, and S. KIMURA, 1955. Beaked whale Berardius bairdii of Japan with notes on ,(iphiuscavirostris. Sci. Rep. Whales Res. Inst. 10: 89-132.
OwEN, R. 1845. Odontography. Vol. I. Hippolyte Bailliere, London. 655 pp.
PERRIN, W. F. 1975. Variation of spotted and spinner porpoises (Genus Stenella) in the eastern tropical
Pacific and Hawaii. Bull. Scripps Inst. Ocean. 21. Univ. of California Press. 206 pp.
PERRIN, W. F. and A. C. MYRICK, (eds.) in press. Age determination of toothed cetaceans and sirenians.
Spee. Issue 3. IWC, Cambridge.
PERRIN, W. F., J.M. CoE, and J. R. ZWEIFEL, 1976. Growth and reproduction of the spotted porpoise,
Stenella attenuata, in the offshore eastern tropical pacific. Fish. Bull. 74 (2): 229-269.
PERRIN, W. F., D. B. HoLTs, and R. B. MILLER, 1977. Growth and reproduction of the eastern spinnerSci. Rep. Whales Res. Inst.,
No. 32, 1980

AGE OF BOTTLENOSE DOLPHIN

65

dolphin, a geographical form of Stenella longirostris in the eastern tropical Pacific. Fish. Bull. 75 (4):725-750.
RIDGWAY, S. H. 1972. Homeostasis in the aquatic environment. pp. 590-748. In: S. H. Ridgway (ed.)
Mammals ef the sea, biology and medicine, Charles C. Thomas, Illinois. 812 pp.
Ross, G.J.B. 1977. The taxonomy of bottlenosed dolphins Tursiops species in South African waters, with
notes on their biology. Ann. Cape Provincial Mus. Nat. Hist. 11 (9): 135-194.
SCHEFFER, V. B. 1950. Growth layers in the Pinnipedia as an indication of age. Science 112 (2907): 309311.
SCHEFFER, V. B. 1970. Growth layers in a dugong tusk. ]. Mammal. 51 (1): 187-190.
ScHOUR, I. and A. W. HAM, 1934. The action of vitamin D and of the parathyroid hormone on the calcium
metabolism as interpreted by studying the effect of single doses of the calcification of dentin. Arch
Path. 17: 22-39.
ScHOUR, I. and M. M. HOFFMAN, 1939. Studies in tooth development. I. The 16 micron calcification
rhythm in the enamel of dentine from fish to man. ]. Dent. Res. 18: 91-102.
ScHOUR, I. and M. C. SMITH, 1934. The histologic changes in the enamel and dentin of the rat incisor inacute and chronic experimental flourosis. Univ. Arizona, Agri. Exp. Sta. Tech. Bull. 52.
ScHOUR, I. and S. R. STEADMAN, 1935. The growth pattern and daily rhythm of the incisor of the rat.
Anat. Ree. 63: 325-333.
ScHouR, I., W.R. TWEEDY, and F. A. McjuNKIN, 1934. The effect of single and multiple doses of parathyroid hormone on the calcification of the dentin of the rat incisor. Am.]. Path. 10: 321-345.
ScHOUR, I., W.R. TWEEDY; S. B. CHANDLER, and M. B. ENGEL, 1937. Changes in the teeth following
parathyroidectomy. II. The effect of parathyroid extract and calciferol on the incisor of the rat. Am.
j. Path. 13: 971-984.
SERGEANT, D. E. 1959. Age determination of odontocete whales from dentinal growth layers. Norsk
Hvalfangsttid. 1959 (6): 273-288.
SERGEANT, D. E. 1962. The biology of the pilot or pothead whale Globicephala melaena (Trail) in Newfoundland waters. Bull. Fish. Res. Bd. Canada 132: 1-84.
SERGEANT, D. E. 1973. Biology of white whales (Delphinapterus leucas) in western Hudson Bay. Fish. Res.
Bd. Canada, 30: 1065-1090.
SERGEANT, D. E., D. CALDWELL, and M. CALDWELL, 1973. Age, growth, and maturity of bottlenosed
dolphins (Tursiops truncatus) from northeast Florida. ]. Fish. Res. Bd. Canada 30: 1009-1011.
TOWNSEND, C. H. 1914. The porpoise in captivity. .Z,oologica 1 (16): 289-299.
TRUE, F. W. 1889. A review of the family Delphinidae. Bull. U.S. Nat. Mus. 36: 1-191.
UTRECHT, W. L. van, 1969. A remarkable feature in the dentine of odontocetes. Beaufortia, 16: 157-162.
YILMAz, S., H. N. NEWMAN, and D.F.G. Poole, 1977. Diurnal periodicity ofvon Ebner growth lines in pig
dentine. Arclzs. Oral Biol. 22: 511-513.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

66

HOHN

EXPLANATION OF PLATESPLATE I
Fig. 1. SEM micrograph of etched longitudinal section of tooth from an old maleTursiops showing relative evenness in GLG width, translucent layer width, andspacing of GLGs. Magnification: X 17.
Fig. 2. Etched longitudinal section of tooth from a 2.5 year old male Tursiops.
The small layers running parallel to the GLGs are incremental layers. Althoughmore than two GLGs are present, the first is deceptively masked so that the actual
boundary layer, marked by the arrow, is not the first prominent ridge. The beginning of the second prominent ridge serves as the boundary for GLG 2. nlneonatal line, al-accessory layer, PC-pulp cavity
Original magnification: X 18.
PLATE II
Fig. I. Longitudinal thin section (transmitted light) of a young Tursiops tooth.
The dark evident line following the neonatal line (nl) may be a " calciotraumaticline". One GLG is complete, the second is beginning. The center accessory
layer (al) is very evident and could easily be mistaken for an additional GLG.
Magnification: X 18.
Fig. 2. Longitudinal thin section of a tooth from a male which could have from 1.5
to 6 GLGs. This animal is probably just over 3 three years old. The GLGs aremarked by arrows. Notice the accessory layers which occur centrally in the first
two GLGs.
nl-neonatal line
Magnification: X 12.
PLATE III
Fig. 1. Etched section of same 2.5 year old male in Plate II, Fig. 2 at a higher
magnification. Notice especially that it is difficult to separate individual
incremental layers (il) because two adjacent layers with small mineral density
differences appear as one.
nl-neonatal line, al-accessory layer
Magnification: X 50.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

乙

086!'
t& "
ON
'
"/SU]・
s
a
gS3/1
1
1
f
;
H ・
r
/
a
g・
！
1
S

1
u

G ＇~ 818

NHO H

J:
JJ,V1d．
，

PLATE I
I

HOHN

S
c
i
.R司
・
'
1 Mノ
h
＇a
l
e
sRe
s.
I
n
s
t.
,
λ（o
.3
2
, 1980Ill~11.V1d0861';;€ '
O
N
'
'
1
S
U
J'S3l
lSJ/Vl/t1'f ・1/3~［ '
.
I
J
S

NHO H

ON THE EXTERNAL CHARACTERS OF GLOBICEPHALA
MACRORHYNCHUS OFF TAIJI, PACIFIC
COAST OF JAPANMANABU YONEKURA
Faculf'JI of Agriculiure, Kinki University, Higashiosaka, Osaka

SUSUMU MATSUI
Taiji Whale Museum, Taiji, Wakayama

AND
TOSHIO KASUYA
Ocean Research Institute, University of Tokyo, Tokyo

ABSTRACTThe external measurements of211 short-finned pilot whales off the Pacificcoast of Japan and the observation of the pigmentation of some of those individuals are analyzed. They have pigmentation pattern fundamentally common to the genus Globicephala. The growth of the trunk is characterized by
the highest growth rate of rostrum portion in fetal stage, and that of theregion between umbilicus and anus in postnatal stage. On some appendages,
the change of growth pattern occurs at parturition and/or after the attainment of sexual maturity of male. G. macrorhynchus is morphologically different
from G. melaena in smaller size of body, and shorter flipper and tail region.

INTRODUCTION
Although the recent existence of the long-finned pilot whale, Globicephala melaena(Traill, 1809), is not confirmed, that of the short-finned pilot whale, G. macrorhynchus
Gray 1846, is known from the coastal waters of Japan (Kasuya, 197 5 ). The species
is less common in the Sea of Japan than off the Pacific coast. They are believed tomigrate seasonally along the Pacific coast between southwesternJa pan and Hokkaido,
though the summer resident are present in the southwestern waters. The seasonal
movement of the northern range of the species between 34°N and 42°N seems to berelated to the movement of the subarctic convergence. In recent years, the driving
fishery at Taiji on the Pacific coast of central Japan is the only fishery taking thespecies constantly in the above range. It is operated usually within a radius of
15 km from Taiji.
The purpose of this study is, based on the sample obtained from the catch ofthis fishery, to make a brief description of the external morphology of the species
and provide some basic data for future analyses of between populations differenceof the external characters.
Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 67-95

68

YONEKURA, MATSUI AND KASUYAThe present study was started as a graduation thesis of Yonekura under thesupervision of Matsui. Later Kasuya joined the study, collected some additionaldata, reanalysed data, and added a section of external pigmentation.
MATERIALS AND METHOD
All the observations of the colour pattern and the external measurements were obtained from the catch by driving fishery off Taiji (33°35'N, 135°58'E).
The measurements of the body proportions used in this study are as follows.
With exceptions of nos. 12 through 19, all the measurements were made parallelto the long axis of the body. Though some of the measurements may differ fromthose customarily used for whales, it does not mean the recommendation of thepresent method.
1. Standard length, from the tip of snout to bottom of the notch of tailflukes.
2. Tip of snout to center of eye.
3. Tip of snout to blowhole.
4. Tip of snout to angle of gape.
5. Tip of snout to anterior insertion of flipper.
6. Tip of snout to tip of flipper.
7. Center of eye to center of ear.
8. Bottom of notch of flukes to the apex of dorsal fin.
9. Bottom of notch of flukes to center of anus.
10. Bottom of notch of flukes to center of genital aperture.
11. Bottom of notch of flukes to center of umbilicus.
12. Flipper, straight length from anterior insertion to tip.
13. Flipper, straight length from axilla to tip.
14. Flipper, curvilinear length along anterior edge.
15. Flipper, maximum width.
16. Dorsal fin, length of base.
17. Dorsal fin, height from base to apex.
18. Width of tail fluke at base, from anterior insertion to bottom of fluke
notch.
19. Distance between apices of tail flukes.
20. Projection of melon beyond the tip of snout, measuered when anterior
end of melon projects over the tip of snout.
The measurements nos. 1 to 19 were made by Y onekura on 143 postnatals
and 17 fetuses in eight schools caught from May to November of 1976. The length
frequency of these specimens is shown in Fig. 1. The provisional analysis of thegrowth of G. macrorhynchus off the Pacific coast of Japan suggests that the calves areborn between 135 and 146 cm, and that the growth stops with large individual
variation at a length between 340 and 395 cm in females and between 430 and 525
cm in males (Kasuya, unpublished). The lower boundary of these ranges situates
about 10 cm above the mean length at the onset of sexual maturity. However,Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

69

40

Ill

iij 30
:J

'O

·:;:
:0
.!:

-

20

0

0

z

10

Standard length in cm
Fig. I. Length frequency of 160 samples (52 males and 108 females) used for theexternal measurement nos. 1 through 19. Shaded square indicates male and thewhite female. Samples smaller than 150 cm in standard length are fetuses ..

these figures are based on the body length measured including the projection of
melon beyond the tip of snout. The standard lengths corresponding to these ranges
are calculated at 337 to 390 cm and 423 to 512 cm respectively. The mode infemale frequency in Fig. 1 may indicate the mean asymptotic length.
The observation of colouration was done by Kasuya, and the measurement
no. 20 was taken by Kasuya and Matsui on the individuals in four schools caught
in February 1980. The purpose of the measurement no. 20 is to analyze the possible sexual dimorphism and to get some clue to convert the "standard length"
generally used in this study into the "body length" measured from the anteriormost
point of head to fluke notch, which might be commonly used for the short-finned
pilot whale. Though the use of the standard length might be adequate for themorphological comparizon between the two species of pilot whales, the accurate
measurement is difficult on adult G. macrorhynchus because, different from G. melaena(Sergeant, l 962a), the anterio-ventral surface of melon directly merges into the tipof snout.
The statistical analyses of the significance of sexual difference of the externalmeasurements are made for each 30 cm length groups, and on the proportion expressed as the percentage of standard length.
PIGMENTATION PATTERN
Except for a few pale areas mentioned below, most of the part of the body of G.
This
brown colour changes black soon after the death.
The most faint lightly pigmented part is the blaze behind the eye, which is anmacrorhynchus is pigmented dark brown on living or freshly dead individuals.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

YONEKURA, MATSUI AND KASUYA

70

Fig. 2. Body contour and pigmentation of G. macrorhynchus off the Pacific coast ofJapan .. Dotted area indicates paler part of body. Drawings are based on photographs and measurements of an adult female.

12
E
u
.!;;

10

c
0

Qi

E

0

8

6
ll' 0 0

c

g
u

•o

4

Q.I

·o
...
a.

0

OOO

OOO

o~
0 0

J'

(•)

2

~

0
0

90

180

Standard

270

360

450

length in cm

Fig. 3. Relationship between standard length and projection of melon beyond thetip of snout. Open circle indicates female and the closed male. A male in parentheses is not used for the calculation of regression.

oblong patch extending from the posterio-dorsal region of the eye to anterior insertion of dorsal fin. Though this patch was found on all the individuals examined,
size and clearness were variable between individuals. This is usually discernible
only through very careful observation of wet skin of the freshly killed individuals.
It is not frequent to recognize it from a distance even on a live specimen. Though
this postorbital patch is not described by Norris and Prescott(l961), it might be universal in the genus of Globicephala.
The second is the postdorsal saddle-mark, which has been described on GlobiceSci. Rep. Whales Res. Inst.,

No. 32, 1980

71

SHORT-FINNED PILOT WHALE

270

3GO

450

1.4

....0

-

,,

~..,

~·

1.3

.v."'"....l'il
c:

0
:;;

u

1.2

()~()

........

(!)

0

u
1.1

0

270

3GO

450

Standard length
Fig. 4. Correction factors to convert the external proportions expressed as the ratioof standard length into those of body length measured from the protruded tip ofmelon to fluke notch. The downward line at the bottom is for the measurement
not including the protruded melon, and other lines for the measurement including
it. X indicates longth from tip of snout, SL the standard length, and the scale atthe top the body length converted from standard length.

phala (Norris and Prescott, 1961; Sergeant, 1962a).

This has large individual variation and generally conspicuous on adult individuals. Though this mark becomes
indiscernible on specimens dead long, it is more conspicuous than the blaze behind
eye. This is most clear when observed on live animals and through the water(Plate I, Figs 1 and 2).
The third is the ventral mark. The pattern is principally common to G.
melaena and G. macrorhynchus. The colour, however, seems to be much darker inthe later species as mentioned by Sergeant (1962a), and no individual of G. macrorhynchus observed in the present study showed such a brightly pale colour of theinguinal region as G. melaena.
GROWTH OF TRUNK

Projection of melon
The melon of full term fetus is small and shaped of the ordinary delphinids'
melon (Plate II, Fig. 1.), however it seems to start the rapid growth after birth andsoon attains the bulbous form. The projection of the front end of the melon
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

72

YONEKURA, MATSUI AND KASUYA50
To nostril

•

. ••.
:

40

rn-··""·
5';,-.,~ ..... '1·····?
<t/o ' ! •!
s"•• •::,a-"-.
o30o,,/''

o,9'

•

•

:

•

E 20

50

•

0

u

c: 10

c:

Cl>

E O

...

Cl>
:::J

~ 40

•

•

Cl>
~

-

0
0

30

20

00

0

•

10

0

To angle of gape00'---'-~L--'-~L-_._~.___._~.___._~.___._~.___._~.___._~.__~

0

90

180

270

360

450

Standard length in cm
Fig. 5. Measurement nos. 2, 3, and 4, measured from tip of snout and expressed byactual length. Open circle and dotted line indicate female and the closed circle
and solid line male. The square and vertical line indicate the range of data and95% confidence range of the mean based on 10 or more female samples. The
scale at the top indicates calculated body length between fluke notch and projected
melon.

over the snout occurs at the length of about 240 cm, which correspond to the ageof about 2 years (Kasuya, unpublished). The relationship between standard lengthand the degree of the melon projection is shown in Fig. 3. Both sexes are expressed by the following least squares equations.
SL;:;:;236
y = 1.257x10-4 SL2-4.517x10- 2SL+3.649,

SL~237

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

73

SHORT-FINNED PILOT WHALE
0•

To nostril

•

14

:J·

12

0
0
0 0

•

•'

••-<t..

/

•/

0

•

:1• •
·m.. i : ~i "·~--...fil..a ..
i

!
l

I

:

4-1 •
:

.:

o

-°' i~LJ..

~
CJ
a_

\

!

o/
,0 .......

-~~

c 12

o.e ,

0

!

.--~'o"~(6• <:J>.

•/

14•·•._o

•

0 :'

10

0

•
• • ••

To eye

lo ~

0

0 CX)

....g--·.

~

•

oO

•

•

10

0

••

• •

0

0

12

To angle of gape

••

0

10

! •

•
•

8
0

0

90

180

270

3GO

450

Standard length in cm
Fig. 6. I'vleasurement nos. 2, 3, and 4, expressed as the percentage of standard
length. Arrow indicates the presence of significant sexual difference of meanvalues (p<0.05). For further explanations see Fig. 5.

where SL indicates the standard length in cm, and y the projection of melon beyond
the tip of snout. Though it is generally believed in G. melaena that the developmentof a huge melon is one of the secondary sexual characteristics, it is shown on G.
macrorf7:,,vnchus that the size of the melon may not be different when compared between sexes of same body length. And even on the adult males exceeding the
maximum standard length of the female, the development of melon is on the sameline. This suggests that the large size of the melon in the adult male is the simple
result of the augmentation of body.
From the above equations the correction factor (r) is calculated in order toconvert the measurement expressed as the percentage of "standard length (SL)"Sci. Rep. Whales Res. Inst.,
No. 32, 1980

74

YONEKURA, MATSUI AND KASUYA

•

•

70
60

E
u

0

,,...........

o,/g

50

,o" ....... , ' 0

0

c

,/

-

40

L.

30

c
E
(!)

o/

•

Ill

re:!

<!I

::E

20

0

...

/
4!/

10

--$'-

I

10

00

~~·.
___Bo,.0

flipper

~/

<!I

::J

To ant. ins.

•

0

90

180

o

0

270

f

... _9.......

•• .. •• •Eye to ear

360

450

Standard length in cm
Fig. 7. Measurement nos. 5 and 7, expressed by actual length.
planations see Fig. 5.

For further ex-

to that expressed as the ratio of "body length (BL )" measured from the end of projected melon to fluke notch. When the measurement does not include the projection of melon, there is a following equation.

If the corrected measurement includes the projection of melon, the correction factor
r is obtained by the following equation,r=(~~~)/(~)
where X indicates an actual length measured from the tip of snout excluding the
projection of melon. The value of r is shown in Fig. 4 for the selected values of

X/SL.
Sci. Rep, Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

•0

0

0

22

To ant. ins. flipper·--c;c;~oe.

"..·•.

•

•

20

-

75

•

18

••

c

C!I

~ 1G
0

G

~~.

4

Eye toear•o...,._______

0

0

90

180

270

360

450

Standard length in cm
Fig. 8. Measurement nos. 5 and 7, expressed as the percentage of standard length.
For further explanations see Fig. 5.
TABLE 1.

COMPARISON OF BODY PROPORTION OF G. MACRORHYNCHUS
BETWEEN FETUS, FULL TERM EETUS, AND FULLGROWN MALE AND FEMALE 1>

Standard lenth, cm

cm
Projection of melon
Rostrum tip to eye
Eye to ear
Ear to ant. ins. flipper
Flipper to umbilicus
Umbilicus to anus
Anus to genitals d'~

Anus to fluke notch
1> Ratio

135 (d' ~)30 (d' ~)

%

R

0
0
3.4 11.4
1.8 6.0
1.4 4.8
8.7 29.1
5.5 18.0

4.4
2.4
2.4
3.4
3.6

0.54 1.8
9.2 30.7

6.0
3.5

465 (d')360 (~)
cm

cm

%

R

0
18.4
6.2
4.8
38.7
25.5
11.1
3.8
41.4

0
13.7
4.6
3.6
28.7
18.9
8.2
2.8
30.7

3.7 1.0
0.89 35.0 9.7
0.98 12.3 3.4
1.8 13.4 3.7
1.5 98.3 27.3
2.2 82.1 22.8%

2.6 13.7 3.8
1.9 118.9 33.0

%

R

cm

1.4
1.3
2.2
2.1
3.4
3.5

9.8 2.1
43.4 9.3
14.0 3.0
15.2 3.3
118.4 25.5
112.0 24.1
49.8 10.7

2.9 162.0 34.8

is shown as the percentage of standard length. R indicates the relative growth rate.

Growth of anterior portion
The characteristic feature of the growth of anterior portion of Globicephala isin the rapid growth in the fetal stage, and in the gradual decrease of the rate after
the parturition (Sergeant, 1962a). The details of the growth pattern, however,Sci. Rep. Whales Res. Iwt.,
No. 32, 1980

YONEKURA, MATSUI AND KASUYA

76

To tip of dorsal fin

280

••
• •
•• •

240

••

• 200

E

u

c:

240

... /i:/9'-c<!> 200.

r//o

E

a·

':J

•

<!>
(/)

160

Ill
QI

:l:

160

0

120

/"

..J:r""

··o-v

80
40

0 ,/'

•

~·l_..fo

120
80. .IJ·····~

mb1hcus

40

•o'

0

/"
..

.. ~·

90

180

270

360

450

Standard length in cm
Fig. 9. Measurement nos. 8 and 11, measured from fluke notch and expressed byactual length. For further explanations see Fig. 5.

differ between the portion at the front of eye and that posterior of it.
The position of the nostril changes drastically. In the early fetal stage it situates at about 6% of the standard length from the tip of rostrum namely at the frontof eye and of angle of gape, and continues to move posteriory during entire fetal
stage. As this movement is much faster than the growth of the rostrum, the nostril
finally comes on a level same with that of eye and angle of gape by the stage of 120 to150 cm in standard length, or the length at birth. At this stage, if calculated combining both sexes, the relative positions of nostril, eye, and angle of gape measured
from the tip of rostrum are 13.8%, 13.7%, and 11.7% of standard length respectively. Though the ratio of head region in the standard length continues to decrease after birth, the relative position of these organs remains almost unchanged.
Another peculiarity of the growth pattern of the rostrum region is the possible presence of sexual difference in the postnatal growth stage. As shown in Fig. 5, nosSci. Rep. Whales Res. Inst.,

No. 32,1980

77

SHORT-FINNED PILOT WHALE•

To tip of dorsal fin

60• •• •

•

55

•• •

0

\---::-----:.
...·
.

0

\,

c(!)

0

•

-~--

•

u

~

•

'·

.....
'-

•

0

"80.
50

•

•

60
To umbilicus

55
0

Oo

50
,.,

......

~• .

.......

0. o'•

0

90

180

270

360

450

Standard length in cm
Fig. 10. Measurment nos. 8 and 11, expressed as the percentage of standard
length. For further explanations see Fig. 5.

tril, eye, and angle of gape of juvenile females situate posterior to the corresponding positions of the male of the same body length. However their relative position
is reversed in the later growth stage. This change occurs at the standard lengthof 300 to 330 cm. Though the samples are not sufficient for the statistical analysisof all the length groups, the sexual difference is significant in some of the groups(Fig. 6). The growth rate of the rostrum region, which decreases after birth, becomes slightly higher at the standard length of 285 to 375 cm in males. This growth
spurt of the rostrum is again followed, after 375 cm, by a stage of relatively slow
growth. On the other hand, the spurt occurs in females at smaller body length orfrom 195 to 285 cm. This will explain the presence of sexual difference in the proportion of rostrum portion at restricted growth stages.
The proportional length between eye and ear also shows a higher relative
growth in fetal stage than in the postnatal. No secondary growth spurt nor sexual
dimorphism is expected for this part. The increase of the actual length of that
section ceases at 330 cm in females and at 420 cm in males. The occipital portion
represented by this measurement is, as in the case of neck region, the place where
the growth is the smallest in both fetal and postnatal stages (Table I).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

YONEKURA, MATSUI AND KASUYA

78

•• •
To genital aperture

180
160

E

••

•••

u

•

c: 140

-

•• •
•
• 140
120

c:
120
E
C!J
....
:::J
Ill 100
(!)

•

100

"'

C!J
~

80
80
60

•

60

40
40
20
20

.

..<fr·
00

0

90

180

270

360

450

Standard length in cm
Fig. 11. Measurment nos. 9 and 10, measured from fluke notch and expressed byactual length. For further explanations see Fig. 5.

The growth of the portion between tip of snout and anterior insertion of flipper
shows a pattern similar to that of rostrum region. However, the ratio to standard
length does not increase even in the fetal stage as observed in the growth of otherpart of head region, but decreases rather slowly, which is followed by a rapid decrease after parturition. The speed of decrease of the ratio in postnatal stage ishigher than that observed on the rostrum portion. This is also an indication that
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

79

•

••

46

~

l

To genital aperture

44

•

l l l
•

•

•

42

c

Q)

u
....

•

40

,. • ••

•

•

•
•• •

.
•

•: •
!
I
:..

... ~;_1~!-~

38

Q)

a..

/•<?.._',,
oo
O''''
'

36

0,/

•
0

0
0

0

o , :

r;f:J-'

~/

!I

ijJ
:I

\ . -6··() I !
0

I

·,

!

! i

I

0
0

36

• •

•

34
0

0

0

32
0

•

30

0

•

•
•

0

90

180

270

360

450

Standard length in cm
Fig. 12. Measurement nos. 9 and 10, expressed as the percentage of standard
length. For further explanations see Fig. 6.

the growth of the portion between eye and anterior insertion of flipper is smaller
than its anterior section.

Growth of rear portion
The four measurements on the posterior region of the body, the lengths measured from fluke notch to anus, to genital aperture, to umbilicus, and to apex of
dorsal fin show a similar feature in the growth pattern, namely the ratio is constantSci, Rep. Whales Res. Inst.,
No. 32, 1980

YONEKURA, MATSUI AND KASUYA

80

-.,,

.3

•
~·
0

'o

0

0

0

a:: .2

Width I Length along

anterior

edge

•

100

• ••

80

E

60

u

••

c
(I)
20
E

~

.,,
(\>

~

~-~

•.c ,,

- /'
::J

l

~ .... {~

c 40

I/)

. • (1,.

0

0

Length•along

anterior edge•g.<f/
00-r«~--.ip··,. ....... }~ .. ·.•..--."' 0

9'"9

60

'

Q~,. ..."'O

•

0

c;··

•

Ant. ins. to tip, straight

40

30
20

,§f'

.0

10
0'---'--'-~'---'--'---J'---'--'----''---'---'----'~-'----'---'~-'--'

0

90

180

270

360

450

Standard length in cm
Fig. 13. Dimensions of flipper, measurement nos. 12, 14, and 15.
explanations see Fig. 5.

For further

or slightly increasing accompanied by the growth of body. This is the reflection of
the fact that this portion retains high growth rate until the cessation of growth inbody length.
No sexual dimorphim is indicated except for the position of the genital aperture. Though, obstacled by the scarcity of the samples, the between sexes difference of the position is not statistically significant in all the length groups examined(Fig. 12), the difference must appear significant in more length groups when larger
samples are accumulated.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

fi.

23
0

21

• •

•

•• •

•

'

•

··"O·

0

.6

•
•

17

c 15

• •

••

0

0

•

0
0

Length along anterior edge

0

•

°"~

•

0

19

:

0
0

~

0

I:
1·

•
•.•t ••
•
0

•
19

81

0

CD

• J1 Straight length

.

•

0

0

o

0

0
0

17

r
:

'

~,,·~··•. ~ o..o

•
0

....

.~-··-"'·· oo

15

•
G

··.:o~•
co~ Width•···-S!.o-..
0

4
0

90

270
360
160
Standard length in cm

450

Fig. 14. Dimensions of flipper (measurement nos. 12, 14, and 15) expressed as thepercentage of standard length. For further explanations see Fig. 6.

Growth of each segment
The lengthwise dimensions expressed as the percentage of standard length become almost constant, in females, after the length of 330 cm. This lower limit
coincides, as mentioned above, with the lower range of the asymptotic length orwith the mean length at sexual maturity. Though the corresponding length of themale will be about 420 cm, the body propotion in the male seems to change evenafter the length. Table 1 shows the mean body proportions calculated from thepresent data of nearby size (± 15 cm). They are mean values at the standard lengths of 30 cm (early fetus), 135 cm (near term fetus), 360 cm (female, approximately at the mean asymptotic length), and 465 cm (male, same as female). This isconsidered to give a rough idea on the body shape of the species. The positionof apex of dorsal fin is not listed, because it situates in any stage of the growth
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

YONEKURA, MATSUI AND KASUYA

82

•

.6

Height I Length

•

0

-.,,
0

• ••
•

0

--~~v._

.4

-

0::

0

"

•

•

•2

60

•••

"'

Height, base to tip

100

E
u

80

•

•
--<Sff>

Pit

-~

•

•

• 40

•

20

•

l• •

.~

c 60

0

•

<II

E

<II

5 40

.,,
Ill

Length of base

<II

~

20
o....__.___,.__....___._~_.___._~..____.___,...._....___.~_.___._~..___,_~...._~

0

90

180

270

360

450

Standard length in cm
Fig. 15. Dimensions of dorsal fin, measurement nos. 16 and 17. For further explanations see Fig. 5.

nearly at the same level with that of umbilicus. The growth rate of each segment
is calculated using the following equation and the data in Table 1,_ X2-X1
R x- X1
where Rx indicates the growth rate of segment X, X 1 the length of X segment at
the start, and X 2 that at the end. When fetus grows from 30 cm to 135 cm, thehighest growth rate is found at the segment between tip of rostrum and eye, andthe next highest at the segment from umbilicus to anus which is followed by thesegments of tail and of flipper to umbilicus. The growth rate of the segment between anus and genital aperture is not included in this comparison, because it isspecial and included in the segment between umbilicus and anus. In the postnatal
growth stage the feature is same in both sexes and the highest growth rate is observed in the segment between umbilicus and anus, the second highest in the tail segSci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

Height, to tip

o~j7/1,···

5

cC!J•:-<T_.-·'?.._~ e o ~o l
0

·-..

0

'··

\. l

~

.

~\\

•

•

!
~

.

Basal length

~

C!J

a. 21

o.

Oo

19

..

0

-------q

0

0

90

180
270
360
Standard length in cm

/

\,
~\

0

•

•

I

.. .•

: ..--i"Vo,c,r··;\,:~--~------~---<>---~-,

.. o

17

0

I

0

~----B--~•••;o ·-- ,
~ ! ----;

,-

0

23

15

• •
••

•

Be

9

83

:

450

Fig. 16. Dimensions of dorsal fin (measurement nos. 16 and 17) expressed as thepercentage of standard length. For further explanations see Fig. 5.

ment, and followed by the segments of ear to flipper and of flipper to umbilicus.
GROWTH OF APPENDAGESFlipper
Since the straight length of flipper was measured on limited number of samples and the data is entirely lacking in adult males, following analyses are done on
the length along anterior edge and on the maximum width. During the fetal stage
the length of flipper increases both in actual length and in the ratio of standard
length. However the growth in the actual length decreases between the full term
fetuses of about 135 cm and newborn calves of 180 cm, and the ratio of the length
expressed as percentage of standard length drastically decreases. This is alreadyobserved on G. melaena in the North Atlantic (Sergeant, 1962a). After this period
the ratio again continues a slow increase, until the animal attains the asymptotic
length over 330 cm in females and over 420 cm in males.
The width of flipper expressed as the percentage of standard length shows aslight increase during fetal stage. After the birth the ratio decreases until 270 cm
in standard length, and then stays almost constant.
The width/length ratio increases in fetal stage and continues to decrease in
all the postnatal period.
Sci. Rep. Whales Res. Inst.,

No. 32, !980

84

YONEKURA, MATSUI AND KASUYA

•
140

•
•

120

E

100

0

c

c

Cb

E

80

•
...l/ 0

60

~

al
I'll

Distance between tipso_ ......-6· •
o·d

0..

40

Cb
~

20

/

0

•

•

•. -g,o-···

0

•

.. 40
20

.~-.0.------0-····

~·
0

90

180

270

360

450

0

Standard length in cm
Fig. 17. Dimensions of tail flukes, measurement nos. 18 and 19.
planations see Fig. 5.

For further ex-

Sexual dimorphism may not exist even where the difference of the means are
statistically significant in the present data.

Dorsal.fin
Length of the base of dorsal fin expressed as the percentage of standard length
increases rapidly in fetal stage and then stays nearly constant in all the postnatal
females and in males below 390 cm. In males the basal length, as in the case of
the height mentioned below, shows a rapid increase at about 420 cm, which may
correspond to the age of sexual maturity. The decrease of the relative basal length
near the parturition indicated by Sergeant (1962a) on G. melaena is not detected on
the present species.
The relative height of the dorsal fin increases in fetal stage and then continues,
in females, to decrease until the maximum body length. In males, on the other
hand, the height too shows a rapid growth at 420 cm in standard length. In G.
melaena the growth of height of dorsal fin is reported to follow the pattern of flipper(Sergeant, 1962a), but it is different in female G. macrorhynchus.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

31

85

•

Tip to lip

•
•

29

0

•
27

•
0

25

c 23
0

21

0

v·

•

..

//

•

·.,j'

0

•0

•

0

0

. •

0 ~

,..

~',,

8

-~

~

0

0

0

0

•
o•

•

.,

••

·1
j

•

Width at insertion

11

0
0

9

-~v·
~
\
~.

!re

•

•0'~

~

~
•

•

0

7
0

~\

00

•

•
90

180

270

360

•

450

Standard length in cm
Fig. 18. Dimensions of tail flukes, measurement nos. 18 and 19, expressed as thepercentage of standard length. For further explanations see Fig. 6.

The height/length ratio increases in fetal stage, and after birth it stays almost
constant.
No sexual dimorphism is detected, when compared between the sexes of thesame body length. However, both the height and length of dorsal fin are larger
in relation to the standard length in full grown males than the females of corresponding stage.
Tail.fluke
Becuase the tail flukes of the fetus are coiled ventrally, the correct measurement of the distance b·etween the apices is difficult to be done. The distance between
apices expressed as the ratio of standard length increases rapidly in fetal stage.
After birth the ratio stays almost constant in all the females and in males below
450 cm in standard length. In the larger full grown males, the distance between
apices expressed as percentage of standard length tends to be larger.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

86

YONEKURA, MATSUI AND KASUYA

The ratio of the width of tail fluke at insertion shows a constant decrease fromearly fetal stage to full grown individuals of both sexes. In some of the length
groups, the mean of the relative width is significantly smaller in females than in
the males of the same body length (Fig. 18). Though such a length range is limited between 300 and 360 cm, the presence of similar trend in smaller length groups
suggests that the difference might be proved as significant in other body length
groups if more samples are accumulated.
DISCUSSION

A comparison of some important external proportions is made between G. macrorhynchus of the present study and G. melaena in the western North Atlantic. Only
the individuals of adult size were selected from the former species. They are 73
females above 330 cm and 13 males above 420 cm in standard length. The dataof G. melaena selected are females above 400 cm and males over 500 cm, which are
expected to be composed mainly of adult individuals (Sergeant, I 962b ).
TABLE 2.

COMPARISON OF EXTERNAL PROPORTIONS BETWEENTWO SPECIES OF GLOBICEPHALA
G. macrorhynchus

1. Standard length (cm)r1~

2. Tip of snout to eye (%)

r1

5. Tip of snout to ant.
ins. of flipper (%)

r1

8. Notch of flukes to apexof dorsal fin (%)

r1

11. Notch of flukes toumbilicus (%)

r1

9. Notch of flukes toanus (%)

r1~

12. Flipper, ant. insertion
to tip (%)
1> Mean

~

~
~
~

r1
~

n

range

mean 1>

13
73
13
63
12
53
11
47
1
16
13
65
0
18

424-491334-392
8.8-10.7
8.4-11.0
15.1-17 .5
14.3-19.0
54.2-61,5
51.3-60.1
60.2
54.8-59.9
32.7-36.4
28.5-35.8

452.6
357.5
9.5±0.3
9.7±0.2
15.8±0.4
17 .0±0.3
57.4±1.5
56.1 ±0.3
60.2
56.3±0.234.8±0.3
33.0±0.3

15.8-18.9

16.3±1.8

G. melaena

n

range

mean 1>

10
10
9
10
9
10
8
9
8
9
10
10
9
10

500-610405-472
7.2-9.3
9.0-10.6
12.6-14.9
14.4-16.3
52.1-57.8
48.2-53.1
58.2-68.0
57.7-63.2
33 .9-41.4
33.8-37.0
24.1-27.4
21.9-26.2

551.8
440.7
8.3±0.5
9.8±0.4
13.7±0.6
15.5±0.554.6±1.551.2±1.561.2±2.460.3±1.3
38.2±1.3
36.1±0.826.2±0.8
23.7±1.0

and its 95% confidence range are indicated.

The comparison in Table 2 shows no significant difference between the two
species in the length from tip of snout to eye, but certainly significant difference inthe length of the tail portion. The length of tail is 3.1 % (female) to 3.4% (male)
shorter in G. macrorhynchus. If the proportion of other segment is calculated from
Table 2, the length between anus and umbilicus is 23.3% in the female of thisspecies and 0.9% shorter than the same sex of G. melaena. The segment between
eye and anterior insertion of flipper and that between anterior insertion of flipper
and umbilicus are 7.3% and 26.7% in female G. macrorhynchus respectively. These
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

87

figures are 1.7% and 2.5% larger than correspoding figures of female G. melaena.
The eye to flipper segment of male G. macrorhynchus is 6.3% and also 0.9% larger
than the value of G. melaena. Though in male G. macror!rynchus the position of umbilicus is not accurately calculated, the length between anterior insertion of flipper
and anus is 49.4%. This is almost same with the corresponding value of the female
50.0%. Accordingly we conclude that G. macrorhynchus has shorter tail and umbilicus to anus egments, and larger eye to umbilicus segment.
In Sergeant (l 962a ), the measurement no. 8 "Notch of flukes to back of dorsal fin" is specified as "Measured to point vertically below apex of fin". This measurement is considered to be same with our measurement no. 8 "Notch of flukes toapex of dorsal fin meaured parallel to the long axis of body". Then, Table 2
suggests that the tip of dorsal fin of G. macrorhynchus is situated 2.8% (male) to 4.9%
(female) anterior to the corresponding position of G. melaena. This is different
from the conclusion obtained by Sergeant (1962a) on the position of the anterior
end of the dorsal fin, where no significant difference between the species was
detected.
About the appendages, the height of dorsal fin is measured in the present study
from the base to the apex. This is not same with the ordinary measurement of vertical height of dorsal fin. Though present method may give a smaller value, theheight in the adult G. macror!rynchus is from 33 to 50 cm in males and 20 to 34 cm infemales. And the similar but different measurements of G. melaena in Sergeant(1962a) are slightly smaller than these range giving the value from 34 to 46 cm inmales and from 25 to 32 cm in females. This is a suggestion that G. macrorhynchus
may have the higher dorsal fin. Based on the same principle, we measured thewidth between the apices of tail flukes which certainly give a smaller figure thanthe measurement of "Total spread of flukes". Though the difference can be significant in fetuses, it may not be large in the adult. The comparison between Fig. 7of Sergeant (1962a) and our Fig. 18 shows that the mean values of the distance between apices in G. macrorhynchus situate above the range of the total spread of tailflukes of G. melaena. This is an indication that the latter species may have smaller
tail flukes. No discussion will be necessary on the shortness of the flipper of G.
macrorhynchus compared to that of G. melaena (Table 2).
ACKNOWLEDGEMENTGreatest thanks are due to Mr T. Sugimori, the director of the Taiji Whale
Museum, and his staff for affording the facilities to M. Yonekura. The Taiji
Fishery Cooperative Union and its dolphin hunting team is acknowledged for theirgenerousness to permit our study in their dissecting platform. Proffesor H. Asanoof the Kinki University provided M. Y onekure with the suggestion of the study.
REFFRENCES
KASUYA, T.,

1975.

Past occurrence of Globicephala melaena in the western North Pacific.

Res. Inst., 27: 95-110.
Sci. Rep. Whales Res. Inst.,

No. 32, 1980

Sci. Rep. Whales

88

YONEKURA, MATSUI AND KASUYANoRRrs, K. S. and J. H. PRESCOTT, 1961. Observations on Pacific cetaceans of Californian and Mexican
waters. Univ. Calif. Puhl. ,(,ool., 63 (4): 291--402.
SERGEANT, D. E., 1962a. On the external characters of the blackfish or pilot whales (genus Globicephala).
J. Mamm. 43 (3): 395--413.
SERGEANT, D. E., 1962b. The biology of the pilot or pothead whale Globicephala melaena (Traill) in Newfoundland waters. Bull. Fish. Res. Ed. Canada, 132: 1-84.

Sic. Rep. Whales Res. Inst.,

No. 32, 1980

SHORT-FINNED PILOT WHALE
APPENDIX
No.
Sex
2

3

4
5
6

7
8
9
10
11
12
13
14
15
16
17
18
19

89

EXTERNAL MEASUREMENTS OF G. MACRORHYNCHUS OFF TAIJI**

1*

2*

3*

4*

5*

6*

7*

8*

9

10

11

J

J

J

J

J

J

J

J

J

J

J

J

48
5.5
5
4
10.5
19
2.8
25
14
17
23
9.5
7

58
7
7
5.5
12
20.5
3.2
29.5
17
21.5
28

67
8
7.5
6.5
14
26
3.5
34
21.5
26
34

101
12
11.5
10
22
44
5
51
32

127
18
18
15
29
57
6.2
64
40
51
66

129
18
18
15
26
50
5.8
66
39
48
61

132
16
18
14
29
58
6
66
39
50
66

140
18
18
15
29

182
20

241
26

234
26
26
21

244
25
25
23

3

12
3.2

8

9

3
4.5
11

3.4
5
13

14
3.8
10
3
6.5
15

40

51

24
6.5
15
7
10
21

71
43
55
69

26

29

8

8

22

22
10.5

27
12
12
35

10
12
26

28

30
8
29
19
14
32

17
37
64
9
85
60
74
100
34
26
35
10
40
16
16
42

55
7

30
8

22

21
46
83

73

79
101
124

91
127

42
12

12

40
31
41
12

44

48
14
48

20
21

22

55

62

21
20

25

* Fetus. ** For position of measurement see text.

APPENDIX
No.
Sex
2

3
4
5

6
7
8
9
10
II

12
13
14
15
16
17
18
19

Continued.

13

14

15

16

17

18

19

20

21

22

23

24

J

J

J

J

J

J

J

J

6

J

J

J

J

253
30
29
25
48
90
10

265
30
30
25
51
92

267
31
31
25

279
30
30
25
49
102
10
147
95
119

282
28
28
23

292
29
31
25

302
34
36
27

308
31
34
26

328
35
35
29
57
107
11
184

343
40
35
34

156
94
123

325
35
38
30
57
115
12
172
100
128

341
38
39
31
59
126
13

160
99
128
169

317
35
37
30
56
118
12
171
98
125
172
60
46
65
17
71
23
27
84

110
142
189
65
50
70
19
70
27
28
94

111
143
187

75
97
130
42
31
49
14
50
20
20
61

128
76
98

13
54
20
22
66

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

81
105
141
52
40
54
15
49
20
24
70

54
15
60
22
23
78

40
31
42
13

23
73

59
21
27
76

51
39
55
16
55
24
25
73

99
129
173
55
41
58
16
57
24
25

77

57
43
61
18
73
25
29
85

147

68
62
25
26
75

11

18
18

29
91

YONEKURA, MATSUI AND KASUYA

90

26

No.
Sex

2
3

4
5

6
7
8
9
10
11
12
13
14
15
16
17
18
19

27

28

29

APPENDIX

Continued.

30

32

31

33

35

34

36

37

38

39

6

6

6

6

6

6

6

6

6

6

6

6

6

6

344
37
40
33
61
127
12
187
116
147

346
37
38
30

352
38
40
31
60
124
13
192
116
147

355
37
41
33
61
116

363

366
38
39
30
65
119
13
214
118
152

370
31
33
27

385
41
44
33
69
136

391
43
43
37
69
137

392
40
42
36

394
40
42
35
68
128

396
41
39
34
64
116

418
42
40
34
72
142

198
121
157

362
36
42
32
64
117
12
208
122
156

200
131
160

223
128
160

214
128
164

227
134
173

228
134
171
225

240
143
182

76
20
71
29
32
98

66
19
64
28
28
78

61
18
65
29
26
91

76
22
86
31
33
102

79
21

67
21
80
29
28
95

82
22

27
91

78
20
79
36
31
99

31
27
110

'52

112
142

65
52
70
20
70
27
29
98

63
17
62
25

203

66
18
67
26
29
83

128

76
21
77
31

APPENDIX Continued.
No.
Sex

2
3

4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

40

41

42

43

44

45

46

47

48

49

50

51

6

6

6

6

6

6

6

6

6

6

r:J

6

6

424
40
40
35
74
136
14
240
145
190

424
41
43
37

432
40
39 .
33
68
156
15
249
145
192

434
38
38
33
69
131
14
238
146
194

439
47
50
43
71
151
14
254
155
198

445
42
45
35
68
151

455
44
44
36
70
1'18
14
260
149
194

459
40
42
35
71
153

473

475
46
46
42
78
159

241
161
204

453
43
40
39
71
162
14
275
155
205

491
48
45
39
76
161
14
291
182
222

100

~

~

~

100

~

~

M

M

~

~

97
26
105

141
185

~
~

34

33

96
36

97
33

93
45

95
41

105
43

98
38

~

M

M

M

~

~

~

M

109

111

106

101

100

103

139

116

163
212
274

37

259
170
225

292
173

222

482
46
43
39
73
155
14
272
165
218

93
25
97
50
36
147

95
26
99
50
32
125

99
26
102
45
30
142

44
41
36
73
142

40
38
135

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE
APPENDIX
No.
Sex
2
3
4

5
6
7
8
9

JO
JI
12
13
14
15
16
17
18
19

2

3
4

5
6
7
8
9

JO
JI
12
13
14
15
16
17
18
19

Continued.

53*

54*

55*

56*

57*

58*

59*

60*

61*

62

63

64

65

Cf'
27
3
1.6
2.5
6
10.5
1.8
14.5
8
8.5
12.5
5
4

Cf'
29.8
3.5
1.8
2.5
6.5
11.5
1.8
15.5
9
9.5
15
5.5
4

Cf'
35.8

Cf'
55

Cf'
67

4

7

9

2.8
3
7 .8
14
2
18.5
JI
11.5
17
7
5.5

6
5
12
21
2.8
26
17
18.5
27.5
JO
7

8
7
14
24
3
32
20
22
32

Cf'
127
19
19
I7
28
54

Cf'
130
19
20
17
29
55

Cf'
130
16
15
14
28

Cf'
190
24
24
21
39
69

Cf'
200
25
25
21

1.8
5
1.5
2.5
6

2
6
2.5
3.5
7

3
9.5
3.5
4.8
10.5

Cf'
190
17
18
I4
34
62
9
96
63
68
105
33
25
35
10
39
I5
17
44

Cf'
200
25
26
22
43
72

1.5
4
1.5
3
5.6

Cf'
30.6
3.5
2.5
2.5
7
12
1.8
15.8
9.8
10.5
15.5
5.8
4.4
6.8
1.6
5.4
2.0
3.2
6.6

49

34
26
35
II
35
15
18
54

12
3.5
10.5
3.5
4.5
13

APPENDIX
No.
Sex

91

6

6

5

65
42
46
66

68
41
44
63

73
39
43
66

99
59
65
99

18

28

27

35

8

7

7

11

26
11
13
31

27
12
12
32

26
12
12
27

85
16
48

104
61
68

31
10
39
16

67
72

Continued.

66

67

68

69

70

7I

72

73

74

75

76

77

78

Cf'
228
28
29
26
48
84

Cf'
254
32
31
26

Cf'
256
29
30
25
5I
90

Cf'
260
25
29
2I
47

Cf'
282
32
34
27
51
99

Cf'
283
32
36
29
52
96

Cf'
290

Cf'
307
30
31
24
50

8

136
82

144
78

143
85

84

156
94

~

%

~

~

149
92
100

Cf'
294
37
35
34
58
IOI
12
157
95
I03

Cf'
304
30
34
26
56

126
76
84
125

Cf'
286
35
38
30
56
92
9
I61
96
100

Cf'
287
34
35
28

II

Cf'
268
30
32
25
50
100
10

136
43
33

138

42
30

%

%

«

138
47
35

13
45
17
20
70

12

13
46
21
21
60

42
12
43
19
18

55

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

21
60

II

I~

~

M

~

~

15
51
17

15
53
22
24
73

13
43
23
22
74

15
53
21
20
70

96
IM

60
25
23
78

49
35
50
15
58
20

54
15
50
24
21
74

160
98
125
54
41
58
16
64
23
25

77

92

YONEKURA, MATSUI AND KASUYAAPPENDIX

No.
Sex

2
3
4

5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

Continued.

79
<jl

80
<jl

81
<jl

82
<jl

83
<jl

84
<jl

85
<jl

86
<jl

87
<jl

88
<jl

89
<jl

90
<jl

91
<jl

312
32
37
26
61
107

313
34
36
29

320
33
35
28
57

TI6
33
35
26
56
113
12
174
104
113

3TI
33
38
28
63
114
11
181
105
117

TI8
32
37
26
58
112
12
189
106
122

334
31
36
26
59
111
12
190
112
125

338
31
34
27
56
115
13

55

62
49
68
18
65
23
25
81

334
35
37
28
58
107
12
183
110
124
191
59
45
67
18
64
25
28
92

335
38
29
24

182
108
118

TI2
30
31
23
51
104
12
182
103
116
183
56
42
60
16
56
20
26
83

3~

169
110
120

321
31
33
25
54
103
12
165
101
113
175
58
41
62
17
60

54
16
49

22

108
121

58
43
63
16
44
19
26
85

54
42
59
61
20
26
73

22
26
85

33
35
27
54
108
12
170
101
115

41
63
17
68
27
24
88

62
18
67
24
25
86

63
18

66
29
26
87

59
44
65
17
71

190
114
124
192

113
126

27
91

59
21
27
85

64
48
70
18
73
25
25
90

22

62

APPENDIX

Continued.

No.
Sex

92
<jl

93
<jl

94
<jl

95
<jl

96
<jl

97
<jl

98
<jl

99
<jl

100
<jl

101
<jl

102
<jl

103
<jl

104
<jl

105
<jl

1

338
30
30
23

340
34
35
28
58
115
13
192
Ill
129

340
35
35
30
65
116

341
35
37
29
63
115
12
188
110
126

341
34
36
27
55
110
12
201
109
119
188
56
42
66
18
61
20
28
85

342
34
35
28
61
116

342
32
35
25
56
110
12

343
37
38
34
60
112

343

344

344

345
33
35
27
60
112
12
190
113
127

345
33
37
26
59
111

345
31
32
24
58
111
12
196
112
126

2

3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19

197
110
120

60
22

58
43
67
18
60
24
26
87

176
120
130

68
18
60
30
20
88

67
19
66
25
28
92

195
120
134

111
123

61
18
68
28
28
95

54
42
57
17
65
25
25
81

193
117
127

192
120
131
198

102
115
193

198
112
129

55

66
18
60
28
23
95

61
17
60
21
27
85

71
18
58
26
26
93

42
59
18
71
26
28
81

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

No.
Sex

2
3
4
5

6
7
8

9
10
11
12
13
14
15
16
17
18
19

APPENDIX

Continued.

93

106

107

108

109

110

111

112

113

114

115

116

117

118

119

~
346
32
32
26
57
122
13
203
111
124
195
60
45
65
18
64
24
27
90

~
347
35
40
29
60
125
12
188
119
129

~

~

347
34
35
28
58
122
13

347
32
32
26
55
110
11

~
347

~
348
33
35
27
57
112
12

~
352
38
39
32
66
123
11

~
352
31
34
27

120
132

111
123
197
59
45
68
18
73
25
26
93

115
130

~
353
35
35
29
59
121
12
196
122
141

~
353
33
35
28
60
112
13
191
119
132

~
354
37
38
28
60
119

110
123
191
60
45
68
17
67
25
27
93

~
348
38
40
35
57
114
11
206
1!8
128

~
354
36
36
30
59
118
12
206
118
128

~
354
32
35
26
58
113
13
190
122
138

61
16
66
27
24
91

64
47
70
18
72
21
25
104

74
19
70
24
28
106

192

65
17
67
23
27
86

62
19
63
32
24
90

APPENDIX

196
126
137
211

60
70
27

61
43
67
18
69
22
28
IOI

63
18
77
26
30

63
24
30
80

201
115
128

63
17
62
23
78

Continued.

No.
Sex

120

121

122

123

124

125

126

127

128

129

130

131

132

~

~

~

~

~

~

~

~

~

~

~

~

I

354

355
35
37
30
64
116
13
198
122
132

355
34
35
29
60
115
13
201
122
137

353
39
34
33

356
34
37
28
51
105
11
189
110
124

357
37
33
32
65
120
11
206
120
132

357
32
34
27
56
112
13

357

~8

~8

3~

~8

39
41
36
68

36
37
29
59
119
13

34
39
31
62
116
12
215
114
126

34
37
27
54
110

~
300
36
39
31
62
129
13

2

3
4
5

6
7
8
9
10
11
12
13
14
15
16
17
18
19

101
125

67
19
71
33
28

99

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

65
17
67
20
29
82

112
125
200

60
17
65
25
28
91

60
48
67
18
73
25
29
90

189
115
130

13
205
123
136

60
45
65
18
70
23
83

66
17
65
24
27
89

81
21
79
33
29
102

122
137

193
112
129

63
47
71
18

64
18

66

58
43
67
18
70

24
29
94

32
25
90

28
90

22

122
135

76
20
69
25
30
96

YONEKURA, MATSUI AND KASUYA

94

No.
Sex
2

3
4
5
6

9

10
II
12
13
14
15
16
17
18
19

Continued.

133

134

135

136

137

138

139

140

141

142

143

144

145

Q

Q

Q

Q

Q

c;>

Q

Q

Q

c;>

c;>

Q

Q

Q

361
39
40
35
67
113

361
37
32
32

361

361

365
32
36
28
54
113
12

365
32
32
29

367

369
37
38
33
66
128

369
37
41
29
63
122
13
218
127
138

371
38
35
31
67
119
12
213
127

372
33
36
27
60
106
12

202

364
35
35
28
60
121
12
202
125
140

365
33
36
27
58
114
12

198
Ill
124
198

363
34
35
27
62
118
12
195
121
133
209

67
18

66
18
71
27
28
84

160

7
8

APPENDIX

12
!99
118
131

68
20
70
30
26
100

116
127
200

65
16

72
20
75
28
30
98

28
85

63
47
68
18
73
24
28
95

131
143
208

117
126
205

69
18
70
24
28
86

APPENDIX

Continued.

205
127
143

74
20
76
29
29
102

31
29
100

70
19
72
27
30
88

146

120
136

No.
Sex

147

148

149

150

151

152

153

154

155

156

157

158

159

Q

Q

Q

Q

Q

Q

Q

Q

c;>

c;>

c;>

c;>

c;>

c;>

I
2

373
39
37
35
65
122

373
36
37
31

374
38
41
33

374
36
36
30
60
116
13
214
126
140

374
33
37
27
66
112
12
192
117
132

376
35
38
29
65
121

377
37
41
30

378
40
37
36
67
126

378
36
42
31

381
34
39
28
59
123
12
204
132
146

387
35
38
32

388
36
38
30
62
124

388
36

392
39
40
34
68
134
14

66
18
73
28
30
83

65
47
72
18
77
28
28
100

73
20
74

71
20
70
28

3
4
5
6
7
8
9
10

215
121
136

123
142

II

12
13
14
15
16
17
18
19

67
20
65
30
30
95

88
17
84
34

220
122
135

118
133
212

73
20
78
30

71
20
80
33
28
100

126
141

72
19
75
30

25
91

117
135
212

229
126
140

31
68
123
14
223
130
144

63
17
82
26
28
82

78
19
66
20
28
91

131
146

75
20
62
29
28
100

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SHORT-FINNED PILOT WHALE

EXPLANATION OF PLATESPLATE I
Figs 1 and 2. Probable G. macrorhynchus showing the saddle mark behind the dorsal
fin. 11 June 1975. 40°38'N, 142°15'E. Surface water temperature 15.9°C.
(Photo by T. Kasuya)
Fig. 3. Full term fetus, 144 cm, female. 3 June 1980. Taiji. (Photo by T.
Kasuya)Fig. 4. Adult female, 345 cm in body length. The dorsal fin and keel on the dorsaledge of tail peduncle are bent on the right side. 16 January 1976. Taiji.
(Photo by T. Kasuya)
Figs 5 and 6. Adult male, 479 cm in body length. 9 October 1976. Taiji.
(Photo by T. Kasuya)
PLATE II
Fig. I. Same individual as in Plate I, Fig. I.
Fig. 2. Adult female, 237 cm in body length. 2 June 1980. Taiji. (Photo by
T. Kasuya)
Figs 3 and 4. Adult male, 498 cm in body length. 3 June 1980. Taiji. (Photo
by T. Kasuya)
Fig. 5. Full grown male, 518 cm in body length. 14 January 1976. Taiji.
(Photo by T. Kasuya)Sci. Rep. Whales Res. Inst.,

No. 32, 1980

95

x
o
z・
￡
￡ '
6
8
0
S
J
！
l・
l
a
f
r
1・
1
1
1
m
7
a
ls
l
a
S
リ・
I
'
l
/
°
'

t

w
ル mmo
務

w
ザ
ト
．

竺豆一一

ー

λ
O
N
l
.
'
.
'
i
)
l
f
U
J V
¥
.VJ
l
S
l
f
!ONV J
)
V
S
l
V人 f

I~I ムV寸d

PL
ATE I
I

YO
了
、
.
EKURA,l¥!
ATSUlANDKA
SUYA

、

S
c
i
.Re
p
.l
l
'
h
a
l
e
sRe
s
.i
n
s
t
.
,
Jt
o
.3
2
,1980

DIATOM FILMS ON WHALES IN SOUTH
AFRICAN WATERSTAKAHISA NEMOTQ 1 i, PETER B. BEST 2 l
KIMIE ISHIMARU 1 > AND HIDEAKI TAKAN0 3 >2)I) Ocean Research Institute, University of Tokyo, Tokyo
Sea Fisheries Institute, Department ef Agriculture and Fisheries, Cape Town
3) Tokai Regional Fisheries Research Laboratory, Tokyo

ABSTRACT

Diatoms found on the skin of minke whales and 4 species of toothed
whales in the waters off South Africa were examined. Typical Cocconeis ceticola was common on minke whales and was also found on a southern bottlenose whale. C. ceticola f. constricta was, on the other hand, found only ona southern bottlenose whale and C. ceticola f. berardiusii was found on a Cuvier's
beaked whale. Stauroneis orympica was found on a Cuvier's beaked whale, akiller whale and a strap-toothed whale. Gomphonema aestuarii and Synedra sp.
were also found on a strap-toothed whale, while an unidentified Navicula sp.
was also found on a minke whale and a strap-toothed whale.
On the assumption that typical C. ceticola is only contracted in high latitudes, its occurrence on whales in the waters off South Africa shows that theseanimals may recently have migrated from colder waters.
INTRODUCTION

Many diatom species on whales have been described in the North Pacific andin the Antarctic (Hart, 1935; Hustedt, 1952; Nemoto, 1956, 1958). Diatom films
on the skin of whales have been mostly found in the waters of high latitudes, and they
have generally been considered common in the colder waters of both hemispheres.
There are few observations of diatoms on whales caught in the waters off South.
Africa (Mackintosh and Wheeler, 1929; Best, 1969). It is generally accepted thatdiatoms (mainly Cocconeis ceticola and its related forms) propagate and form films on
the skin of cetaceans in colder waters and are not so common in temperate waters,
although Gambell (1972) has speculated that the lack of ectoparasites on whales
at Durban may have been due to the greater rate of epidermal decomposition in
the higher sea temperatures prevailing there.
In recent studies of whales caught or stranded on the coast of South Africa,
22 specimens of diatom films from skin or teeth have been collected. These specimens are examined taxonomically and the occurrence of diatoms as skin films ofwhales is discussed in relation to hydrographic conditions.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980, 97-103

98

NEMOTO, BEST, ISHIMARU AND TAKANOMATERIALS AND METHODS
Diatom samples were collected between 1969 and 1973 by one of us (Best)
from whales caught or stranded around South Africa. Host species included bothbaleen and toothed whales (Table 1 ).
Diatom specimens were mostly collected from the skin but one diatom film wascollected from the teeth of a strap-toothed whale. The samples from minke andbottlenose whales were collected immediately after death while they were alongside or on the deck of the catcher. Those from the other species were collectedfrom stranded animals some unknown time after death. All samples were preservedin 10% formalin/sea water with the skin of the whales. The diatom samples werethen scratched from the skin and washed with distilled water and rinsed three orfour times. After preservation in potassium permanganate for 24 hours, hydrochloric acid was added and the samples kept for a further 24 hours. After boiling for
5 minutes, the samples were washed and rinsed several times, and frustules of diatoms were kept on plates. Double coating of carbon and gold was used for electron
TABLE 1.
Specimenno.

DIATOM SAMPLES* FROM WHALES FROM SOUTH AFRICA

Date
collected

Species

Length(m)

Sex

Localityt

69/10

July

5 '69

Killer whale (0. orca)

6.10

M

73/10

Oct. 25 '73

5.77

F

75/1

Jan.

19 '756.43

M

33°361 S 28°041 E

78/15

Apr.

6 '78

Cuvier's beaked whale(<;. cavirostris)
Southern bottlenose
whale (H. planifrons)
Strap-toothed whale(M. layardii)
Minke whale(B. acutorostrata)

Bordjies Drif
Cape Point
Still Bay

5.46

M

Milnerton

8.53

M

29°301 s 32°51 1 E

7.62
9.14
7.62
7 .92
8.23
8.23
8.23
8.23
8.84
9.14
8.64
8.28
8.15
8.28
8.86
8.43
8.61

M
F
F
F

U71/2200

Aug. 28 '71

U71/2201
U71/2202
U71/2203
U71/2211
U71/2232
U71/2243
U71/2245
U71/2313
U71/2315
U73/1255
U73/1256
U73/1299
U73/1304
U73/1306
U73/1446
U73/1559
U73/1839

Aug. 28 '71
Aug. 29 '71
Aug. 29 '71
Aug. 30 '71
Aug. 31 '71
Sept. 5 '71
Sept. 5 '71
Sept. 16 '71
Sept. 18 '71
June 24 '73
June 24 '73
June 26 '73
June 27 '73
June 27 '73
July 17 '73
July 29 '73
Sept. 28 '7"3

M
M
F
F

M
M

29°57 1 s 31°19 1 E
30"461 s 31°19 1 E
30"48 1 s 31°58 1 E
31°101 s 30"551 E
31°06' s 31°01 1 E
31°11 1 s 30"461 E
31°051 s 31°47 1 E
30"04 1 s 31°35 1 E
30"42 1 s 33°25 1 E

F
M

M
M
M

31°10' s 31°01 1 E
30°321 s 31°491 E
30"22 1 s 32°04 1 E
31°15 1 s 31°25 1 E
30"27 1 s 31°17 1 E
29°45' s 32"12' E

MF* All samples taken from skin except 78/15 where sample taken from teeth.
t All animals collected at sea apart from 69/10, 73/10 and 78/15, which were all stranded animals.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

99

DIATOM FILMS ON WHALES

microscopy. The specimens were examined with both scanning and ordinary electron microscopes.
The scanning electron microscope JSM-35 was mainly used for the identification of species. Some species are still under examination, but their preliminary
identification is described in this paper.
DESCRIPTION OF SPECIESThe species of diatoms identified and the host species of whales involved areshown in Table 2.
TABLE 2. DIATOMS OCCURRING ON THE SKIN AND TEETH
OF WHALES IN THE WATERS OFF SOUTH AFRICA
Minke whale

Cocconeis ceticola(typical form)
C. ceticola f. constricta
C. ceticola £ berardiusii
Stauroneis olympica
Navicula sp.
Gomphonema aestuarii
Synedra sp.

Southernbottlenose
whale

Cuvier's
beakedwhale

Killerwhale

Straptoothed
whale

18

Only pennate diatoms were found in the diatom films examined. There wereclear differences between the diatom species on different host whales. The typicalform of Cocconeis ceticola Nelson was found on every minke whale but only a very
few individuals on one of the toothed whales examined (southern bottlenose whale).
On the skin of the southern bottlenose whale, some specimens of C. ceticola were
somewhat deformed and a clear constriction was observed. The edge of the valves
was sometimes absent as shown in Fig. F in Plate I. Small numbers of a slender
form of C. ceticola were also found on this whale. On the Cuvier's beaked whale
the more slender form of C. ceticola was found, but with no constriction at the edge
where the stauros of the lower raphe reaches the edge. This type of C. ceticola has
been found previously on the skin of Baird's beaked whale Berardius bairdii (Kriashtorin, 1962), and is named as the form berardiusii.
The constricted form of Cocconeis ceticola has often been observed in toothed
whales. As indicated in Plate I F, the constricted parts sometimes lack the outeredge of the valve, and the hole on the inside is deformed as indicated in Plate I H.
The hole in the edge of typical Cocconeis ceticola is rather similar to other holes along
the edge (shown in Plate I B, C) or a little deformation is observed as shown in
Plate I E.
Four other species of pennate diatoms were found on toothed whales. Stauroneis olympica Hustedt was found on the Cuvier's beaked whale, killer whale andstrap-toothed whale. This species has clear pseudosepten from the tips of the cell,
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

100

NEMOTO, BEST, ISHIMARU AND TAKANO

which is different from the pseudosepten and the shape of the tip of S. omurai N emoto(Nemoto, 1956) found on sperm whales in the North Pacific. The shape of S.
olympica as originally described (Hustedt, 1952) is more slender than these specimens
and the structure of the stauros may be somewhat different. However, considering
the varieties within one diatom species on different species of whales, these specimens may be attributed to the Stauroneis olympica complex. The closely related species S. aleutica reported by Nemoto (1956) can also be put in this group. Stauroneis
diatoms were also present on sperm whales off South Africa, Chile and Australia(Best, 1969). The presence of Navicula species (possibly Stauroneis olympica, as described from the epiphytes on barnacles on a humpback whale from the Antarctic)
was described on a sperm whale landed in the Outer Hebrides (Hart, in Clarke,
1956). This species is possibly cosmopolitan or bipolar on sperm whales and toothed whales (Hart, in Best, 1969).
Small naviculoid diatoms were found on the strap-toothed whale, and werealso found in the film of Cocconeis ceticola on the skin of one minke whale. Gomphonema aestuarii Cleve which is also described by Giffen ( 1966) in South African
waters, and Synedra sp., which is very close to S. tabulata (Ag.) Kupzing (Harrison
and Thurley, 1974), were also found on the teeth of this strap toothed whale.
DISCUSSION

Studies of skin films of Cocconeis ceticola have suggested that these diatoms aremost common on cetaceans in the colder water of high latitudes.
Mackintosh and Wheeler (1929) concluded that such diatom films on whales
are undoubtedly contracted in the austral summer in Antarctic or sub-Antarctic
waters. Hart (1935) described the general tendency for the rate of diatom film
infestation of blue and fin whales to increase as the season progressed at South
Georgia. Gambell (1968) also noted the diatom infestations on sei whales caught
at South Georgia; and that sei whales newly arrived from the breeding grounds inthe middle of the summer season do not bear diatoms. However, Mackintosh andWheeler (1929) also noted that small spots of C. ceticola were seen on a few immature (fin and blue) whales at Saldanha Bay, South Africa. Best (1969) and Bannister (1969) recorded the presence of C. ceticola on sperm whales (mostly large or
medium-sized males) off Donkergat (South Africa) and Albany (Western Australia) respectively, during the autumn and winter. Cocconeis diatoms have also beenrecorded from whales in the Eastern Pacific off South America (A. Aguayo L., pers.
comm.). Clarke (1956) found no clear infestation with diatoms of Cocconeis typeon the sperm whales caught in the Azores.
Diatoms in the northern part of the North Pacific, where many diatoms arefound on the baleen and sperm whales, have been described by Nemoto (1956).
Diatom infestation is common in the Bering Sea and its adjacent waters, while inthe coastal waters, Cocconeis diatoms are often observed on both sides of the Pacific;
off British Columbia (Pike, 1953) on the eastern side, and in the Okhotsk Sea andoff Hokkaido waters in Japan on the western side (Omura, 1950). Cocconeis cetiSci. Rep. Whales Res. Inst.,
No. 32, 1980

DIATOM FILMS ON WHALES

101

cola Nelson is the most common diatom on baleen whales. The varieties and formsof C. ceticola in the North Pacific have been described and discussed by Usachev(1940), Nemoto (1956, 1958), Nemoto et al. (1977) and Kriashtorin (1962). According to these authors, the typical Cocconeis ceticola form is only described frombaleen whales. Kriashtorin (1962) reported some large-sized C. ceticola as a newvariety, C. ceticola var. arctica, but this is clearly the same type of C. ceticola fromits shape and size. The fact that the typical form of C. ceticola has now been foundon the skin of minke whales caught off South Africa suggests that minke whales
are similar to other rorquals as host-types. C. ceticola has also been recorded fromminke whales in the Antarctic (Ohsumi et al., 1970), but no remark was madeconcerning the type of C. ceticola involved.
Cocconeis ceticola f. constricta Nemoto is found on the skin of sperm whales in the
North Pacific (Nemoto, 1956). C. ceticola has also been recorded from sperm whales
off Donkergat, South Africa (Best, 1969) and off Albany, Western Australia (Bannister, 1969) : no distinction was made, however, between form constricta and typical ceticola. Cocconeis diatoms found on the Hyperoodon planifrons in the waters off
East London, South Africa, were of two types. A very few specimens of typicalC. ceticola forms were found, but the rest were all constricted forms. Constricted
forms found in this study show some variation although there was no clear boundary to separate them. One was typical C. ceticola f. constricta which was previously
found on sperm whales (Nemoto, 1956). Kriashtorin (1962) also described thesame type from sperm whales in the Far Eastern seas. It was clearly shbwn that theedge of the raphe-valve where the stauros reaches was absent or deformed. The
second type of constricted form was similar to C. ceticola f. berardiusii which was firstdescribed by Kriashtorin (1962) from Berardius bairdii. This type (Kriashtorin,
1962 in Fig. le) is the same as the type M in Fig. 3 in Nemoto (1958), and wascommon among the diatoms on thecavirostris examined in this paper. As no
Cocconeis specimen was found on the killer whale in this study, it is difficult to as-,sess the position of Cocconeis orcii Kriashtorin described by Kriashtorin (1962).
From the surface structure shown by him, C. orcii is one variety of C. ceticola and is
not a valid species.
The global distribution and occurrence of parasitic diatoms on whales are interesting. As stated previously, Cocconeis diatoms are mainly described from thehigh latitudes of the North Pacific and Southern Hemisphere, where they can form
films over a large part of the body (Bennett, 1920). Cocconeis diatom infestation onwhales in lower latitudes is usually rarer and much smaller in extent ("small spots"Mackintosh and Wheeler, 1929), so it might be concluded that such animals arerecent migrants from higher latitudes. The only resident cetacean population outside the Antarctic known to carry Cocconeis films is the Franciscana dolphin, which
lives in water from 13-23°C (Nemoto et al., 1977). Presumably therefore it is possible to contract Cocconeis films in water as warm as 13°C, but as little is known
about the seasonal incidence of diatoms on or movements of the Franciscana dolphin it is impossible to give an upper limit to the temperature range in which C.
ceticola can survive. On the assumption that the films of Cocconeis on the largerz.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

NEMOTO, BEST, ISHIMARU AND TAKANO

102

cetacea are contracted only in high latitudinal waters, the presence of C. ceticola onminke whales off Durban from June to September indicates that the animals haverecently arrived from colder waters, and that the migration may be more protracted
over time than for other baleen whale species. The presence of Cocconeis films on
H. planifrons andcavirostris off South Africa is the first indication that these
species may also migrate from Antarctic or sub-Antarctic to warmer waters.

z.

ACKNOWLEDGEMENT

We would thank Mr G. Smith, boatswain of the whale-catcher C. G. Hovelmeiner for his kind assistance in collecting diatom samples from minke whales in
1973.
REFERENCESBANNISTER, J., 1969. The biology and status of the sperm whale off western Australia- an extended summary of results of recent work. Rep. int. Whal. Commn, 19: 70-76.
BENNETT, A. G., 1920. On the occurrence of diatoms on the skin of whales. Proc. Roy. Soc. London, 91: 352-

357.
BEST, P. B., 1969. The sperm whale (Physeter catodon) off the west coast of South Africa. 4. Distribution
and movements. Invest. Rep. Div. Sea Fish. S. Afr., 78: 1-12.
CLARKE, R., 1956. Sperm whales of the Azores. Discovery Rep., 28: 237-298.
GAMBELL, R., 1968. Seasonal cycles and reproduction in sei whales of the Southern Hemisphere. Discovery Rep., 35: 31-134.
GAMBELL, R., 1972. Sperm whales off Durban. Discovery Rep., 35: 199-358.
GIFFEN, M. H., 1966. Contributions to the diatom flora of South Africa-III. Diatoms of the marine littoral regions at Kidd's Beach near East London, Cape Province, South Africa. Nova Hedwigia, 13 (I &2): 245-292, 5 pls.
HARRISON, R.J. and K. W. Thurley, 1974. Structure of the epidermis in Tursiops, Delphinus, Orcinus andPhocoena. pp. 45-71. In: R.]. Harrison (ed.), Functional anatomy efmarine mammals. Academic Press.
HART, J., 1935. On the diatoms of the skin film of whales, and their possible bearing on problems of whale
movement. Discovery Rep., 10: 247-282.
HusTEDT, F., 1952. Diatomeen aus der Lebensgemeinshaft des Buckelwals (Megaptera nodosa Bonn.). Arch.
Hydrobiol., 46: 286-298.
KRIASHTORIN, L.B., 1962. The diatoms of the skin film of whales in the Far-Eastern seas. Trucfy Inst.
Okeanol. A. N. U.S.S.R., 58: 314-321.
MACKINTOSH, N. A. and J.F.G. Wheeler, 1929. Southern blue and fin whales. Discovery Rep., 1: 257-540.
NEMoro, T., 1956. On the diatoms of the skin film of whales in the northern Pacific. Sci. Rep. Whales Res.
Inst., II: 99-132.
NEMOTO, T., 1958. Cocconeis diatoms infected on whales in the Antarctic. Sci. Rep. Whales Res. Inst., 13:

185-191.
NEMOTO, T., R. L. BROWNELL, ]R, and T. lsHIMARU, 1977. Cocconeis diatom on the skin of Franciscana.
Sci. Rep. Whales Res. Inst., 29: 101-105.
0HSUMI, S., Y. MASASKI and A. KAWAMURA, 1970. Stock of the Antarctic minke whale. Sci. Rep. Whales
Res. Inst., 22: 75-125.
OMURA, H., 1950. Whales in the adjacent waters of Japan. Sci. Rep. Whales Res. Inst., 4: 27-113.
PIKE, G. C., 1953. Two records of Berardius bairdii from the coast of British Columbia. j. Mamm., 34 (!):

98-104.
UsACHEV., P. I., 1940.
torin)

Diatoms propagation of the skin film of whales.

Z,ool. Z,h., 19 (2).

(In Kriash-

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

DIATOM FILMS ON WHALESEXPLANATION OF PLATE
PLATE I
Figures A.D.F.G. are taken by light microscope, B.C.E.H.K.L. are taken byscanning electron microscope and l.J. are taken by Electron microscope.
A. *-raphevalve of Cocconeis ceticola Nelson typical form found on minke whale(B. acutorostrata) U73/1299. B.-raphevalve of C. ceticola ·typical form on minke
whale U73/1304. C.-raphevalve of C. ceticola typical form on minke whale U71/
2200. D.*-raphevalve of C. ceticola typical form on minke whale U71/2203. E.raphevalve of C. ceticola typical form on minke whale U71/2245. F. *-raphevalveof C. ceticola f. constricta Nemoto on southern bottlenose whale 75/1. G.-raphelessvalve of C. ceticola f. constricta on southern bottlenose whale 75/1. H.-raphevalveof C. ceticola f. constricta on southern bottlenose whale 75/1. I.*-Gomphonema aestuarii
on strap-toothed whale, 78/15. J. *-G. aestuarii on strap-toothed whale. K.Stauroneis olympica Hustedt found on killer whale 69/10. L.-S. olympica found on
killer whale 69/10.
* External views of valves, others are internal views.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

103

ON
;'
[
;
;
086!'

S
!'
u'
a
/
1・r
担1
v
1
a
fs
l
J
S
U['
S
/
'
'

山一

z

τ

凶げ

l4
・
ー
−
−

内
7

内︸ヨ

﹈ G
的

コ
一
的
:
¥
.
nIVWIHSJgムS3U '01.0附 3
ム O.¥:Vf
V
J
‑
;
V
J
‑
:
0

d
l
V'
U.
'
.
I'

'•··················....

BRAIN ORGANIZATION IN PLATANISTA GANGETICATOSHIRO KAMIYA*
Department of Anatomy, Faculty of Medicine, University of Tokyo, Tokyo

PAUL PIRLOT
Departement des Sciences Biologiques, Universittf de Montreal, Canada

ABSTRACTThe quantitative composition of the brain of a young individual of P.

gangetica is presented both in simple percentages and with progression indices refering to a basal mammalian type. The neocortical development isemphasized as well as the hippocampal reduction. This species ranks low
among Odontoceti and even among Platanistids, which may be considered inagreement with its life-habits. Qualitative features of transverse sections arealso presented.
INTRODUCTION

A detailed study of dolphin brains is not easy because the size of that organ in most
species makes it difficult to prepare histological sections. We have, however, beenable to carry out a gross and microscopical examination of one such brain belonging to a young individual of the Ganges dolphin (Platanista gangetica indii), collected by the first author in the Indus River in Pakistan. We present here ourobservations of the most important quantitative characteristics of the composition of that brain with an appendix on some of its external and internal features.
We hope that, although the animal was not an adult, a basic description of its brain
will be useful as a reference type for those having to identify the main characteristics of bigger, more unwieldy specimens.
MATERIAL AND TECHNIQUES

An individual of Platanista gangetica mesuring 106.5 cm and weighing 17.5 kg wascollected from the Indus River in Pakistan. It is assumed to have been about one
year old at the time ofdeath. The weight of its brain was 170 g. That brain was
fixed in 1/6 formalin solution. One sagitally cut half of it was embedded in paraffin, sectioned at 10 µm and Nissl stained. Photographs of 108 sections from frontend to back-end were prepared. The above laboratory operations took place inMontreal (collection number P285) while the final study was carried out in Tokyo.
The photographs were used to estimate the volumes of nine main components of* New address:

Anatomical Laboratory, College of Medical Thechnology, University ef Tsukuba, Ibaraki 305,

Japan.
Sci. Rep. Wltales Res. Inst.,
No. 32, 1980, 105-126

106

KAMIYA AND PIRLOT

the brain according to the technique explained elsewhere (e. g. Stephan, Bauchot
and Andy, 1970).
ABBREVIATIONS

Here are the abbreviations used throughout this paper for the brain components.
N =neocortex; Rh= rhinencephalon or paleocortex ( P) ; S =septum; D = diencephalon; St=striatum including the area of the <::apusula interna that is spread out
considerably; H=hippocampus; M=mesencephalon; C=cerebellum including
pontine fibers; O=medulla oblongata.
RESULTS AND COMMENTS

We shall report here on the quantitative aspects of the brain of P. gangetica, leaving
for the appendix a few remarks on its qualitative morphology. In fact, quantitative comparisons are not easy in this case because few biometrical data have been
published on dolphin brains. We do not know of any analysis of such material
carried out with a method similar to the one applied in the present paper. Therefore, we shall have to refer to studies of other animals. We will consider especiallysome Primates since it is classical to insist on the high degree of both encephalization and corticalization in the two orders Cetacea and Primata. For comparison
purposes, we have selected a small number of data from Stephan, Bauchot andAndy (1970-see their Tables 1 to 6 for more details).

A. Percentage composition
Table 1 presents the absolute and percentage composition of the brain of P.
gangetica while Table 2 shows the percentages of its telencephalic parts only. An
approximate idea of brain structure can be gained by looking at those simple ratios;
however, these do not indicate the comparative evolutionary trends since they do
not take into account the allometrical correlation betweeh brain and body. They
only provide a general picture of the subdivision of the brain, the functional significance of which must bf". interpreted if comparisons are made. We picked up
about a dozen Prosimians and as many Simians from the Tables in Stephan, Bauchot
and Andy (1970) and made approximate estimates of some proportions of brainparts in those Primates.
We can offer the following brief comments.
a) The absence of an olfactory bulb is well known in Odontoceti, as is thecase for P. gangetica.
b) The most important component of P. gangetica's brain is the neocortex.
The abundance of sulci and gyri in many cetaceans has been observed since long,just like the increasing complexity of cortical folding in an ascending series of Primates.
c) The second largest component is the cerebellum. One could possibly
expect this on the assumption that agile swimmers need a well developed cerebelSci. Rep. Whales Res. Inst.,
No. 32, 1980

BRAIN ORGANIZATION IN PLATANISTA

107

lum in order to steer their complicated movements through their environment.
Breatnach (1960) mentions that Mysticeti have a slightly larger cerebellum (20%)
than Odontoceti (15%) and our specimen stands even a little lower (12.77%).
That author also questions the direct relationship often established between aquatic manoeuvering and cerebellar size (o.c. p.221 ). Other ecological situations
and types of locomotion, especially flying and climbing, are also expected to require
an important cerebellum, as the common belief goes. We may note that the cerebellum may range quantitatively from 11 to 16% of total brain in Prosimians of
all sizes and from 8 to 15% in Simians and man. In Megachiroptera, it varies
from 12 to 16% approximately and in Microchiroptera from 15 to 22% (Pirlot andPottier, 1977).
d) Among cortical structures, the rhinencephalon (paleocortex with amygdaloid area) is notably small in P. gangetica. This agrees, of course, with the loss ofolfactory bulb and nerve. However, the amygdala complex is still present and constitutes most of the volume and probably almost all of the functions of that component (strictly speaking, the name rhinencephalon for that region in a dophin is hardly appropriate if it is true that most or all of the olfactory function has disappeared). Note that the relative size of that component remains fairly large in somePrimates although, in the course of evolution, it has regressed in many of them morethan in our dolphin.
TABLE 1.

VOLUMES AND PROGRESSION IN THE BRAIN OF P. GANGETICA

Components

Volumes (mmS)

Percentages of
total brain

Progression
indicesNRh

107,504.73
3,599.59
332.909,893.12
5,743.82
1,161.10
3,564.35
20, 193.24
6, 171.96

67.98
2.27
0.21
6.25
3.64
0.73
2.25
12.77
3.90

3,903
123
132
719
739
99
432
671
325

158, 164.90

100.00

s
D

St
H
M

c
0

Total brain

170 g with body-weight 17. 5 kg .................................... B42

TABLE 2.

N
Rh

s
St
H

P. gangetica

Prosimians

Simians

90.85
3.04
0.28
4.85
0.98

Max. 80

4-10

Up to 88-95<4, even < 1

5-8
5-10

<5, even <1

100.00Sci. Rep. Whales Res. Inst.,
No. 32, 1980

TELENCEPHALIC COMPOSITION(%)

2-3

108

KAMIYA AND PIRLOTe) The relative smallness of the hippocampus is amazing. This fact is alsomentioned for cetaceans in general and in particular for Tursiops turncatus but without any figure by Kruger (1966). We would also agree up to a point with Breatnach and Gold by (1954, p.280) who point to the "indefinitedness of the boundary"of the hippocampus, resulting in the introduction of "quite a large uncertainty into
the estimate of the sectional area" of that component. We did experience difficulties in drawing some hippocampal demarcations from Nissl stained sections.but webelieve that our method was not grossly inaccurate.
f) The septum as demarcated in our dolphin brain cannot probably be compared with other published data because we have restricted our demarcation to aminimal area including the nuclei in strictly paraseptal location, which probably
is not the case in other works. We follow Jacobs, Morgane and McFarland's(1971) practice of including the diagonal band within the olfactory area (o.c.
p. 206) whereas other authors prefer to pool it with the septal nuclei (Stephan,
Bauchot and Andy, 1970, p. 295).
In conclusion, the quantitative composition of the brain in the young P. gangetica is characterized by an overwhelming predominence of the neocortex that approaches that found in higher Primates. Most components are relatively small
mainly because the neocortex and, to a lesser but also significant degree, the cerebellum are enormously developed. The oversizing of the neocortex can be demonstrated to take place in early prenatal life already while the fast growth of the cerebellum seems to occur mainly in late prenatal life (Pirlot and Kamiya, in preparation).

Evolutionary progression
The method of progression indices proposed firstly be Stephan to describe theevolutionary level attained by mammals, then applied by him and other authors(e. g. Stephan, 1967; Pirlot and Stephan, 1970; Stephan and Pirlot, 1970; Pirlot
and Pottier, 1977) to various species, has also been used here. A summary of its
principles can be found in Pirlot and Stephan (1970) and the relevant technique
is described in Stephan, Bauchot and Andy (1970). In brief, comparisons are madebetween the volumes of the brain (or brain-component) in the species under investigation and the volumes of the brain (or brain-components) in an idealized primitive type ("basal Insectivore") that would have the same boqy-weight as the animal
being studied. So, the allometrical relationship between brain and body is taken
into account, which allows to describe and compare evolutionary stages in animals
with various overall sizes. The basal value is 100 so that any figure above 100
indicates evolutionary progression while any figure below 100 betrays evolutionary regression.
From that viewpoint, it can be seen that P. gangetica stands rather low among
dolphins. Its encephalization index (brain-to-body progression) is 842 and this is
not high for its order. Still it is probably a little higher than it would be if the individual investigated were not a young but a fully adult individual. An averageindex found from a sample of 8 individuals was 675 (Pirlot and Kamiya, 1975).
B.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

BRAIN ORGANIZATION IN PLATANISTA

109

From the latter publication, it can also be seen that several other dolphins havemuch higher encephalization indices, up to 2,308. It may noted that, from Stephan, Bauchot and Andy's tables (1970), a progression index of about 2,900 can beobtained for Homo sapiens.
As could be expected from the simple percentages, whatever progression there
is in the total brain of P. gangetica is due mainly to its neocortex being so large(3,903). That figure stands higher than those for a number of Primates but remains
much lower than those for ~everal monkeys and, of course, for apes and man (seea selection in Table 3).
TABLE 3.

COMPARATIVE PROGRESSION INDICES
Br

N

Rh

c

Homo sapiens
Pan troglodytes
Cercopithecus ascanius
Colobus badius
Cobus albifrons
Tarsius syrichta
Galago senegalensis

2,881
1, 132
872
688
1,205
507
417

15,576
5,858
4,448
3,353
6,065
2, 148
1,485

142
54
100
59
87
78
85

1,872
780
551
536
921
514
490

Platanista gangetica

842

3,903

123

671

Br=total brain; other abbreviations as above.

Figures rounded.

The rhinencephalic cortex sensu lato (paleocortex) is low but progressive whereas it may be very regressive in Primates. As already suggested above, if olfaction
has been lost altogether in this dolphin, some other not unimportant activity may
have been taken up by that brain region (amygdaloid area in particular).
Septum development probably follows Rh to some extent. However, onemust keep in mind the remark made before that we have pooled the diagonal bands
together with Rh, not with S.
The striatum and diencephalon are less progressive than in Homo but they
probably yield "average" values for higher mammals.
The hippocampus' lack of progression is puzzling (its value lies practically at
the neutral level 100). In percentage of the telencephalon, its value is close to
man's own (about 0.95 ), but in the latter the evolutionary progress is around 400(rough estimate from figures in Stephan, Bauchot and Andy, 1970). We have refered earlier to other authors who seem to be as unable as we are to propose an explanation for the hippocampus of the delphinids being very small. True enough,we are surprised to find it so small. That fact suggests both an evolutionary functional regression as well as a relative undersizing (influenced by the relative enlargement of the cortex). Contrary to our observations and those of Kruger (1966)and other authors apparently (through Kruger), Pilleri (1972) finds the amygdala
and hippocampal gyrus " .. comparatively" large (o.c. p. 51 ). Pilleri does not give
any measurement and thus we wonder what his words "comparatively large" maymean. The gyrus hippocampi is present on but a few sections from our animal.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAMIYA AND PIRLOTJIO

The mesencephalon can probably be considered fairly progressive (cf. Primates, Chiroptera, etc.) and so can the oblongata.
The cerebellum, often expected to be very progressive in skilled swimmers
such as dolphins, is not remarkably high by Primate standards, however. It ismuch more progressive than in bats (range 200-400), on the other hand, and thebats that are highest in that respect are those performing complex and accurate
slow movements such as vampire, rather than the fast straight-line flyers that catch
insects on the wing.
CONCLUSION
Although showing a great development of its brain and some of its brain components, P. gangetica appears as a rather modest dolphin from that viewpoint. The
relative size of its neocortex, by comparison with other mammals including otherdolphins, may look impressive but, when refered to body-size, probably remains
among the most lowly of the family. We do not, unfortunately, possess accurate
data for such apparently "smarter" genera as Tursiops, Delphinapterus, Phocoena andeven Inia among the Platanistidae. But knowing the general size parallelism between total brain and neocortex in advanced mammals (Primates, Cetaceans), we
may expect those other genera to possess more progressive cortices than Platanista.
The idea almost immediately arises that, in a general way, a river dwelling andonly modestly sociable dolphin like P. gangetica (Pilleri, 1970) has remained "in-

3'

3.<>
2.5

31:
...

2.0

m
bO
0

-I

1.5

1.0

0.5

0

2

3

4

s

-r6

Log B-0W
Fig. I. Log regression for brain-to-body growth in Stenella, Pontoporia and Platanista.
The black dot represents the specimen used for brain analysis in this study.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

BRAIN ORGANIZATION IN PLATANISTA

111

ferior" in neocortical performances to species that are open-sea dwellers, live inlarge schools and are said to maintain refined social communications between individuals (Stenella, Tursiops etc.) In order to illustrate the relative encephalizationof P. gangetica by comparing it with Pontoporia (coastal dolphin) and Stenella (highsea dolphin), we have reported the position of our specimen of P. gangetica on agraph showing average regression BrW/BoW straight lines for those three genera(Fig. 1). In all likelihood the stronger increase in relative brain-size observed in
Stenella is to be related with the postnatal "training" that seems to occur in thatsocial species (Pirlot and Kamiya, 197 5 ).
On the other hand, structures directly concerned with accousti functions, suchas the subcortical components 0 and especially M, do show a strong progressionin Platanista. This fact appears quite remarkable if one compares dolphins withbats which yield indices in the 200-250 range for Mand in the 100-200 range for
0 (Stephan and Pirlot, 1970; Pirlot and Pottier, 1977). Considering that dolphins,
like bats have simplified optic but highly sophisticated acoustic functions, those
figures are particularly significant in Platanista (432 and 325 ).
The basic quantitative findings reported in this paper clearly suggest that further and more detailed investigations on the structure of each brain component
in this dolphin and in higher types are likely to be rewarding. Studies of thequantitative composition of the brain in bats and in other mammals alreadypointed to the same idea. As for dolphins, there has been a fashionable excitementin the last few years about those aquatic mammals being almost as intelligent, inseveral respects, as man itself, or even ''smarter" than Homo sapiens in some. It
will take a lot more data on both the qualitative and the quantitative aspects ofthe dolphin brain to "relocate" such claims into reality, and many, many more
observations of their behaviours.
APPENDIXON SOME QUALITATIVE FEATURES OF P. GANGETICA'S BRAIN

This appendix is made of short remarks A) on a sample of 8 low magnification
photographs of the brain sections used for the above quantitative analysis, B) on
the gross external morphology of 4 views of another brain of P. gangetica and C) on
the most obvious features in 9 sections of the brain-stem of the same specimen.
The animal used for B) and C) was a female individual 120.5 cm long with a brain
weighing 236 g. It was thus a little older and larger only than the specimen P285
mentioned above. It was collected together with the former by the first author in
the course of his expedition to Pakistan.

Sections for quantitative analysis
Demarcations of main areas have been made by following the few photographs
published on dolphin brain and, in the absence of relevant pictures from dolphins,
by resorting to atlases for various Primates. Photomagnification X ea. 2.
Fig. 2. Front part of the right hemisphere with distended ventricle. Section

A.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

112

KAMIYA AND PIRLOT

1061.
Fig. 3. Plane of emergence of a little distinct paleocortical region, in caudad
direction. Section 1506.
Fig. 4. Septal plane. Ventral P reduced. Section 1856.
Fig. 5. Caudad to commissura anterior. P reduced to small lateral area.
Tuberculum olfactorium visible ventrally. Section 2206.
Fig. 6. Pontine fibers plane. Emergence of H and a few fimbriae visible.
Colliculus superior. Section 2906.
Fig. 7. Colliculus inferior and cerebellar peduncle plane. Nucleus cochlearis.
Section 3356.
Fig. 8. Plane at caudal edge of H. Caudal part of colliculus inferior. Maximum extension of 0. Section 3506.
Fig. 9. Caudal N. Typical outline of Cetacean C with developed paraflocculus in particular. Section 3956.

B. Gross external morphology
Fig. 10. External aspect of the calve brain. A) Dorsal view. The fissural pattern is one of the simplest found among dolphins. The longitudinal sulcus constitutes the main sulcus. B) Ventral view. Olfactory nerve absent; optic nerve very
thin; acoustic nerve well developed. The contrast between the last two nerves is
especially notweorthy. C) Lateral view of the left half. We cannot engage here
into a rediscussion of sulci and gyri nomenclature. There seems to be very little,
if anything, new to contribute from the examination of this specimen. For generalsurface anatomy of dolphin brain, the reader is referred in particular to Gruenberger (1970). D) Median section of the right half. The high development of thecolliculi inferiores can be appreciated.

C. Sections throught the brain-stem
The internal structure of the brain-stem in P. gangetica is illustrated here. The
brain-stem was prepared into serial sections which were stained by the WcigertPar carmin technique (embedding in celloidin, sectioning 30 µm thick). Microscopical study revealed many remarkable peculiarities in the development of thevarious component structures. The sectional planes shown here are as follows.
Fig. 11. Section through the inferior end of the medulla (ser. no. 120).
Fig. 12. Section of medulla through the cuneate nuclei (ser. no. 255 ).
Fig. 13. Section through the rostral portion of the medulla at the exit thepharyngeal-laryngeal fibers to nerves IX, X and XI from nuclei ambigui (ser. no.
450).
Fig. 14. Section through the middle of the trapezoid body at the level of thegenu of the facial nerve (ser. no. 555 ).
Fig. 15. Section through the colliculus inferior at the level of the colliculi inferiores commissure (ser. no. 635).
Fig. 16. Section through the middle of the colliculus inferior at the level ofcolliculi inferiores commissure (ser. no. 690).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

113

BRAIN ORGANIZATION IN PLATANISTA

Fig. 17. Section through the colliculus superior, brachium of the colliculus inferior and nuclei for the oculomotor nerve (ser. no. 795 ).
Fig. 18. Section through the colliculus superior, nucleus ellipticus, nucleus interstitialis and tractus opticus (ser. no. 830).
Fig. 19. Section through the thalamic nuclei (ser. no. 900).
ACKNOWLEDGMENTS
We wish to thank Dr F. Yamasaki and Dr T. Kasuya, members of the Universityof Tokyo Cetacen Research Expedition, for their help in collecting the Platanista
brains in Pakistan. Mrs H. Rietveld-Fernandez carried out the histological preparation and the photographic work at the Universite de Montreal. Financial
assistance to both authors for all phases of the research was received from theJapanese Government's Ministry of Education, Science and Culture and the second
author's sojourn at the University of Tokyo was also largely funded by the Natural
Sciences and Engineering Research Council Canada (grant A0778).
REFERENCES
BREATHNACH, A. S., 1960. The cetacean central nervous system. Biological Rev., 35: 187-230.
BREATHNACH, A. S. and F. GOLDBY, 1954. The amygdaloid nuclei, hippocampus and other parts of therhinencephalon in the porpoise (Phocaenaphocaena). ]. Anat., 88: 267-291.
GRUENBERGER, H. B., 1970. On the cerebral anatomy of the Amazon dolphin (Inia geojfrensis). Investigations on cetacea, 2: 129-144.
KRUGER, L., 1966. Specialized features of the cetacean brain. In: K. S. Norris (ed.) Whales, dolphin andporpoises. Univ. of California press, 232-254.
JACOBS, M. S., P. J. MoRGANE and W. L. McFARLAND, 1971. The anatomy of the brain of the Bottlenose
dolphin (Tursiops truncatus). Rhinic lobe (Rhienencephalon). I. The paleocortex. ]. Comp. Neur.,

141: 205-271.
PILLER!, G., 1970. Observations on the behaviour of Platanista gangetica in the Indus and Brahmaputra
Rivers. Investigations on cetacea, 2: 27-60.
PILLER!, G., 1972. The cerebral anatomy of the Platanistidae (Platanista gangetica, Platanista indi, Pontoporia
blainvillei, Inia geoffrensis ). Investigations on cetacea, 4: 44-70.
PILLER!, G., C. KRAUS and M. GrnR, 1968. The structure of the cerebral cortex of the Ganges dolphin.
microsk-anat. Forsch., 79, 373-388.
PrRLOT, P. and T. KAMIYA, 1975. Comparison of ontogenetic brain growth in marine and coastal dolphins.
Growth, 39: 507-525.
PIRLOT, P. and T. KAMIYA, (in preparation). Embryonic brain-growth in a dolphin.
PrRLOT, P. and J. POTTIER, 1977. Encephalization and quantitative brain composition in bats in relation
to their life-habits. Res. Can. Biol., 36: 321-336.
PIRLOT, P. and H. STEPHAN., 1970. Encephalization in Chiroptera. Can.]. Zoo!., 48: 433-444.
STEPHAN, H., 1967. Zur Entwicklungshi:ihe der Insektivoren nach Merkmalen des Gehirns und die Definition der "Basalen Insektivoren ". Zoo!. Anz., 179: 177-199.
STEPHAN, H., R. BAUCHOT and 0. ANDY, 1970. Data on size of the brain and of various brain parts in
Insectivores and Primates. In: Noback, C. and W. Montagna (eds.) The primate brain. AppletonCentury-Crofts, New York, 289-298.
STEPHAN, H. and P. PIRLOT, 1970. Volumetric comparisons of brain structures in bats.
zoo!. Syst. Evol.
forsch., 8: 200-236.

z.

z.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

;II
!

'
¥
J
O
￡・
；
0861 ＇
S
'
!
u.
a
f
r
1I・
!
/
l
J
I
/
J
NS
J
S
1・
1
1
‑
s
1
・
'

nION I V~IH
:
:
V
!
¥
.
VZJ
.
.
J
V..LS/1~「V..L V1d ~ I父Ol

6
11

A AND PIRLOT
¥llY
KAl

,
!.
s
n
s.i
.J1 ・~1ales Re
.Rψ
i
c
S
0
8
9
λ匂 32,1.

LII￡ 'Ol{
60861 '＇S！
・／Sllf 'SJlfSJ{Vl/.11 ・l/3~／ ・
・

J
:
.
l!
i
'
01・.

V1JH
J0 NI
NV!)1
ムVZI
0l
:
¥
V.LSINV.LV1d NI1

Formatio
reticularis

︑
一・

nHnμ

−
可 nu

．
同U F E

3UHU

m

凸 ﹂ 円u
d

︑
︒nc

r・ 可l

みし白﹄

HV

白﹄

l

Ventrolateralcell group

Dorsolateralcell group。

Fissuramediana vent.

Funiculus
ventralis

Fasciculus
cuneatusαコハ﹀ぞご 吋 ﹀ ﹀Z C
﹄
u
F
﹁

Oベ

＝
勺

何億円九・

弔
h筒
︑−

s
v
s〜2 42 bEFW

ロ九︿︒
・ M Nhuh﹄086［ Z
f
i'
O
N
"
1
s
u
1・
s
a
ys
a
1
v
1
1
;
1I・
φU'
!
'
S

−

<D Eご

け

−
ω AM

℃日コ

τoヨ のaA 印 コ
no − ︺ 由 τoc ℃︿のコけ

M O︺ 白 け の 可 印 −

V>

コ
可

、

u

hlJb

︐
﹃
nm − − 由 ﹃ 8 0 C匂ロO

Aい 中 山ωcσ 明け印コ︒﹃
︐ m 仰 の 印 no コけ・

付−

~.

<D ~.

ー−印

.
.
.
.
.
.
.
.
.
.
.
.

ZEn −− nc コ め 白 けCM↓τ noτ Anom

コz
τn
< ̲
.
.
~.

．

~・τ

−
τ
<
.
C
l

ヨコ

コ・4

ー

.
,

・
.
.

−

・
コ
て

F﹄

.
.
.
.
.
.
亡
コ

「
＋

．
喧 V>
4

<
.
C
l

－－＇·~

明 3
4nc cmaoτ 帥印−Am

．．
τ

コー寸

<
D <D

ヨの

コc

、

~·V>

u V>

n印

<D コ
ヨ印

。け
・
'
S ~.

コ
ー
．

c0

ヨ

~.V>

V
J
,
S
J
NVLV?d NINO l.LVZ I NV!J~IO N I V~I H

61
1

I
く八恥I
IY八 八 代 D PJRL
OT
1
20

代刈

コaLoυJUELO Ffμ 凶山L 日
れ・

mz oF UMmL

．
3ε・

．
パVC 山 ﹀a ．
℃由E

コ

．目的出U U国 ． ﹀FF0 ．
FU Z

コA ？μ 日 山 ﹀ ．c
FFa 凶 ．FU
コZ
町 f
戸 田c

コ

c

F F m咽﹀・

・日L O℃．FU Z

Sc
i
.Re
/
1.I
V
ha
l
e
sRe
s.l
n
s
t.
,

N
o
.3
2
,1
980

0
86！ Z
!
i・
o
.
N
.
「
1日ゲ・ S3ijS3/Vl
f
JH ・
＜
／3
i
j・
口S

−

け 可 印 ℃ 巾N O斗 広 巾 A

zcnプ no Bち・−zcnプ nonz m 白τ・︐a
︿ 巾 コ け ・ ︵ 刀 印 ﹃moτω ・︶ヨ巾 a A C的−uoa−nm
τ 巾σ巾−プ

I
Z
I

く
R

r・
。

‑‑(

3

τ

、
ぞ
。

コ戸コ

(
)>
.
.
.<

，．
「

、
→"
"
0
.
.

寸

コ
可

"
1

c+
.
.
.

白

コ

.
.
.
.
..

"
..

"
1

r
、
。
ν、
コ
て
..

"

~

コ
て

、
，
、

r
o
』
ト
。
.
.
.

守

1

"

ヨ日

r
on
0
.
.

印
。
~コ

.
.
・ uコ
u

、

0
.
.

、
＂

G
"
>

u

r
o
コ

c
:
:r
o
コ
て p
.
.
r
o
τn

Eこ

コ

・巾
。
「

4

＋、
ー
』
。
c
、
..
，
。
」
ー
・
、
官

寸巾

Eア

r
o

ー
．
〕

J,

r
o

"

ー
．
ー
u、

c
:
:
ヨ

V
.
L
S
l
NV.LV1d NlNOl
ムVZI
NVOllONlVlIH

−
＋し

戸
﹄

unH
為

ιU

v nu

白﹂

・
−

F

白﹄・可︐
FLVF

AU D −

ρ
v

n
ヒ Hu

N
u
c
l
. pontis

E
司﹃

N
uc1
.c
o
r
p
.
trapezoidei

EEB
司

N
u
c
l
. lemnisci
lateralispbqd

Formatio
reticularis

Colliculus
inferior
pas

N
u
c
l
.t
r
.mesenceph.
nervi trigemin
i

N
u
c
l
.c
o
l
l
.
inferior

ト~

ト
.

．
ヌ﹀Yニ J﹀﹀ンニ︶−
ヱ−2．0 Jd．

・1a 白﹂Haa

φ L P﹂

n

SS

＋し白﹄

LU−−︐
HUF

h
saphh
4
h凡・河内
市
・ −
2 bミ ・・︿︒・凶い戸︑uhq︑．

−h偽札・ 河内 ＝さミ2hE−
h w
p

︑
−
いw
・
町
老
hp ﹄匂hb

〜
−

c011.

P

pontisNucl.

Lemniscusslaterali

Colliculus
inferior

ιーマミ量一一一：：~： ~~~~raF

Nucl.lemnisci .
.
s.
laterali．
・.
Fasc. long
s
li
a
medi

k

．
.
『司h

−』
．−
−

Brachium
conjunctivuma
Substanti
grisea cent.

l.
col
Nucl.
inferior.
l
Brachium colinferior

一ー
・
・
．

~

−
'
"
‑
'

h
Z もh斗 寸込﹂︿﹄G 叫k
2 0−N︒﹀Z N﹀吋HOZ −
ロ−N﹀−

P3
EE
噌

−

﹄

cdnH
UM

u
n

−
︑
︐
HU
U
H

可

l JU

Ea
a ・
a
門ヨ
C司
・
司
・

﹁﹄＋し

aunu
l
﹁﹁ 司

cdnH

。
N

Basis ped.
cerebri

J
V

m
vI

nUHU

−
−

＋し・

司

・c
s1
s
l
n
nu−−みし

u

can
e
rG
n
u

HUP
し・可tu

h u p﹂−

Fossa interpeduncularis−−
一J．﹀﹀ V L U

Lemniscus
medialis

Brachium
coll
.i
n
f
.

Commissura
c01
1
.s
u
p
.

同

中
．

ヌ﹀y

Hunu
− −
−
HUF

．
︐ nu
︑
・
F
i
w 白﹂

守1

HU

︑

lap J
可

n
v

Fu

E

e
a

l

︑
．
・m
1

HunH
F
﹂・1E

11 由︑
dnuJ
﹃

LH ・可t

nド F
・
戸﹄＋L

P﹂

nH
・TB

e
sv
r

由﹄戸︑

m川 nH

．
r

＠
Nucleusperipeduncularis

sr

Nucl.nervi
oculomotori
i •·

＼

aa
FE
＋
L nヨ

︐
︑
．2nHu nH
︑
．
み
し
1

c
J

hu
・

︑Hu
p

J︾

Tl

句ミ
﹁・河内
2・bE w
︑− てbbeh勾
−
〜
u
hE
LJ S
・ 凶い戸〜

も
匂
<
o

巴
？

、

~

守
句
史
旬

m

〜
〜
。
志
電
、
、

－」－、L~

さ
。
く待
、

'

ι
四
、E亨
曹
士 [. :¥.I

ιf"! M"'"也

Z' .. ‑

ー

＠

−
.
.
， マ錨成

T
r
. opticus

可

"
'
‑
‑

ミ
型
事
｝

Area
tubercularis

Infundibulumljas
1s peauncu11
cerebrivent.

Commissuracoll.superior

y警芝＼

J

I
'

/

、
h
h

＿
：
＿ム必議v
笠

市..，：~.法 曹，・

弘司
，
．：
・ J

Nucleus~~~－－ _,l~－－~interstitialis・ z• －~ ~. ＇λdNucleusellipticus‑

泊·~ f'1o1.l1冒~畠 ・・ー

cerebri .＂，...~＇ 司－·－＇瓦咋 ~－.， ：〜占 「

F

Coll
icul
us
superior
元
置配
置
司
監
，
，

Pulvinar(Nucl. post.
二モ thalami)

−
．
−
−
ー
．
．ー
−

L
、
。
、

巴

、レ、
→
:
~

；
？
込
寸

、
ト
．
司

＝
司

乙
：

。

→
子
〉
、
J

~

，
、
，

;
:
:
i

同

。
。

ロ
~

Nucleus
subthalamicu
s

N
u
c
l
. lateralis~ .~イpost. thalamif
,
‑
"
て、

N
u
c
l
.medialis•.
thalami・ −河内︑
h
a
t
h同河内
M
E
同・﹃ミ旬︑J
− 4

−
一

3ぺ
.｝
〆／

ー：二~q~~ . ‘

＼
， ；、
う
；
：、．

Fundus striati

Basis pedunculi
cerebri

Commissura
posteriorCommissura
coll.superior

caro
su
m

C>

、3

ヌ ﹀？ ﹃︷︿﹀ P・ヌ一↓
o−−Hケ0MF︿・いwu戸 ︑U匂司
L︒

A COMPARATIVE MORPHOLOGICAL STUDY ON
THE TONGUES OF MANATEE AND
DUGONG (SIRENIA)FUSAO YAMASAKI, SHUNRO KOMATSU
Department of Biology, Sapporo Medical College, Sapporo

AND

TOSHIRO KAMIYA*
Department of Anatomy, Faculty of Medicine, University of Tokyo, Tokyo

ABSTRACT

Tongues of two species of manatee, Trichechus senegalensis, and T. manatus, and of the dugong, Dugong dugon, were observed macro- and light microscopically. The tongue, with an anterior short free tip in both families, wasa slender, firm, very muscular structure set rather vertically but with adipose
tissues being rather rich in the posterior part. No circumvallate papillae,
sulcus terminalis, and foramen caecum could be seen on the dorsum. The
lingual apex was rounded in the manatee and truncated in the dugong. While
many digitiform, cuticular spines were present in the tip region, in dugongthey extended further posteriorly and were shaggier than in manatee. The
remainder of the dorsum of the manatee was quite smooth whereas that ofthe dugong had small elevations, some of which had a bunch of spines. A
pair of multifossulate swellings was present on both posterior margins withanother pair occurring on the posterior part of the side wall in the manatee.
In the dugong, two rows with pits could be seen on either of two regions corresponding to the dorsal swelling in the manatee. Similar pits were also
found in a group at the base of the lingual side wall. These structures on thedorsum of both manatee and dugong are homologous to each other, as arethose on the side wall. However, those on the dorsum and side wall may exhibit variations in the vallate and foliate papillae, respectively. Taste buds
were limited to the thin epithelia of the fossulae of the swelling in the manatee
and to the epithelia of the pits in the dugong. Mucous glands, though partially mixed ones, in the manatee and well developed serous glands in thedugong opened into the fossulae and pits, respectively. The posterior glandular portion contained well developed pure mucous glands. The lateral surfaces were studded with round, flat patches in the form of large-sized fungiform papillae, which may act as tactile organ.

* Present address:
Japan.

Anatomical Laborato'f)1, College of Jl.{edical Technology, University of Tsukuba, lbaraki 305,

Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 127-144

128

YAMASAKI, KOMATSU AND KAMIYAINTRODUCTION
The sirenian order is one of three major mammalian groups (along with cetaceans
and pinnipeds) that have adapted to living in water. There are two living sirenianfamilies; manatees (Trichechidae) and dugongs (Dugonidae). Trichechidae has
only one genus, and that genus is classified into three species; Trichechus manatus,
T. inunguis, and T. senegalensis. On the other hand, among Dugonidae, only one
species, Dugong dugon, now remains. As sirenians feed on water plants (being entirely
vegetarian) in shallow water, their digestive systems are interesting and differ considerably from those of cetaceans or pinnipeds. Not a few morphological observations have been made on the tongues of manatee or dugong (Rapp, 1857; Owen,
1868; Murie, 1870; Gmelin, 1892; Beddard, 1897; Weber, 1904; Gudernatsch,
1907, 1908, 1909; Sonntag, 1922; Aoki et al., 1938; Hill, 1945; Gohar, 1957; Nairet al., 1975; Husar, 1978). However, most of these descriptions excepting Gudernatsch's (1908, 1909) have been very brief and ambiguous, and comparative studies of manatee and dugong tongues have been very scarce. Since we have identified some differing morphological characteristics on the tongues between the two
families, the results are reported here and offered as an addition to the knowledgeof sirenian tongues.
MATERIALS AND METHODS
Two tongues of the African manatee, Trichecus senegalensis, one of the West Indian
manatee, T. manatus, and three of the dugong, Dugong dugon, were used for this study(Table 1 ). The African manatees (body length 158 cm, male, specimen No. TS-1;
and 198 cm, male, TS-2), sent by boat from Africa in a frozen state, were given us
by the Ocean Research Institute of the University of Tokyo. The West Indian
manatee (body length 282 cm, male, TM- I) was provided by the Yomiuriland
Aquarium, Tokyo. One of the dugongs (138 cm, male, DD-1, collected in thePhilippines) was imported for scientific research by permission of the Philippine
Government, while the other two (204 cm, female, DD-2; and 254 cm, DD-3, collected in Indonesia) were provided by the Okinawa Expo Memorial Park Aquarium, Motobu, Ja pan. After dissection, the tongues of these animals were fixed with
10% formalin solution in our laboratory. Following gross anatomical observationsof the tongues, materials for histological observations were excised from several
parts of the tongues and were embedded in paraffin or celloidin. Sections madefrom these materials were stained with hematoxylin-eosin.
OBSERVATIONSGross anatomy
The tongues of the sirenians, both manatee and dugong, observed were firm andhard muscular structures. They were slender when viewed from the dorsal aspect(Figs 1 and 6), and were set rather vertically due to the narrowness of the space
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

TONGUES OF THE SIRENIA

129

between the mandibular rami. There were no median sulcus, vallate papillae,
sulcus terminalis or foramen caecum on the dorsum. Since the anterior two-thirds,
which was elevated, was divisible from the posterior lower glandular portion, forconvenience sake we regarded the anterior and the prosterior as the body and theroot of the tongue, respectively, in this study. Measurements of the tongues areshown in the following table.
TABLE 1.

Specimens

MEASUREMENTS OF THE TONGUES OF MANATEESAND DUGONGS OBSERVED
Sex

Length*(cm)

Breadth**(cm)

Thickness***
(cm)

158
198

male
male

14
15

3
3

2.5
2.5

282

male

19

4

4

138
204
254

male
femalefemale

10.5
13
16

2.7
3.5
4

2.5
3.5
4.2

Body length(cm)

Trichechus senegalensis

TS-1
TS-2
Trichechus manatus

TM-1
Dugong dugon

DD-1
DD-2
DD-3

* Whole length from the lingual apex to the base of the epiglottis.
** The widest portion at the posterior of the lingual body.
*** The thickest portion from the floor of the mouth at the mid-part of the body.

The anterior free tip of the tongue, without frenulum, was short, about 1 cm
to 1.5 cm in length, and the tongue, ventrally, was extensively attached to the floorof the mouth, indicating that the sirenian tongue may possesses only limited mobility. The tip of the tongue of the manatee was rounded (Fig. 1) while that of thedugong was truncated (Fig. 6). The tongue of sirenians thickened progressively
from the anterior to the posterior part of the body, and thinned in the posterior
glandular portion, the lingual root (Figs 2 and 7). The mid-part of the dorsum of the
body was considerably convex, both lengthwise and transversely in the dorsal direction. In the dugong, a wide longitudinal elevation of about one-third of the lingual width was seen on the mid-part of the dorsum, thus forming lateral strips oneither side. In the young dugong, DD-1, the lateral strips were not so marked.
The anterior dorsum in the African manatee, approximately 2 cm in extent fromthe apex, was covered with many hard, digitiform, cuticular spines, each about 2
mm in length and 0.2 mm in thickness, which were anteriorly directed along thecornified hard anterior margin (Fig. 1). Small amounts of fine, soft spines wereseen extending almost to the posterior half of the lateral margin. In the West Indian manatee, the anterior margin was rather uneven in appearance, and a few
spines, 1 mm or less in length, were seen in several parts along the margin. In
both species of the manatee, the dorsum, excluding the anterior spine covered region, was quite smooth, both to touch and the naked eye, and was devoid of thepapillous processes seen in other land mammalian tongues. In the dugong, the anterior dorsum of the tongue, about 1.5 cm in extent from the apex, was thickly covSci. Rep. Whales Res. Inst.,

No. 32, 1980

130

YAMASAKI, KOMATSU AND KAMIYA

ered with hard spines quite closely resembling those in the manatee, though far
shaggier (Fig. 6). Anterior spines extended to the ventral side of the free tip, being about 5 mm in breadth and having a clear border. Smaller and softer spines
than those in the apex region occurred on the anterior fourth of the mid-part andon lateral strips, except at the middle longitudinal elevation. In the case of theyoung dugong, DD-1, they extended far posteriorly covering almost all of the dorsal surface of the body and were shaggier than those in the apex region. Spines
in the dugong were stained dark brown in color, probably by the juices of seaweed.
In the dugong, the lingual dorsum had small elevations, 0.2 to 1 mm in diameter,with superficial minute unevenness, especially remarkable along the mid-line area
except for the tip region. A bunch of digitiform spines grew on the elevations (Fig.
8), showing the patterns of what Gohar in 195 7 called "papillae calici-penicilliformes".
In the manatee, specific areas with many fossulae forming pairs were present nearboth posterior lateral margins of the dorsum (Figs 1, 3 and 4). There were roughly
25 to 30 rather large fossulae in the area, each area being clearly distinguishable
from the neighborhood. These areas formed remarkable swellings, multifossulate
swellings, in the African manatee (Figs 1, 3 and 11) but not such remarkable ones in
the West Indian manatee (Fig. 4). The swellings, with gradual thinning anteriorly,
were slightly opened anteriorly. The swellings in the African manatee were approximately 2 cm long and 0.7 cm wide in the posterior part; was 2.5 cm long and
0.8 cm wide, in TS-1 and TS-2, respectively; and was about 2 cm long and 0.8 cm
wide in the West Indian species. Another multifossulate swelling was present oneither lateral wall, in the anterodorsal region of the palatoglossal arch (Figs 2 and 5).
This lateral swelling was about 0.8 cm across in TS-1, and 1 cm in TS-2, and had
about six to eight fossulae*. Since the swelling of this area was rather more poorly developed than that of the dorsal swelling, and since a part of the lateral swellingintermingled with the patches which are mentioned later, the boundary of the lateral swelling was rather inconspicous compared with that of the dorsal swelling.
Some fossulae resembling those of the swellings were seen at the lingual margin between the dorsal and lateral swellings. Therefore, at first sight it appeared thatboth the dorsal and lateral swellings were fused each together into one continuous
large swelling**. Fossulae at the swellings were rather elliptic, about 1 mm inminor and 2 mm in major axes, and were arranged in a rather parallel mannerin the African manatee. Fossulae located at the posterior part of the dorsal swelling in the West Indian manatee were rather shallow and composed of several minuteglandular openings. Many small glandular openings were observable on the dorsum
from the region between the middle part of both dorsal swellings to the epiglottis.
In the case of African manatee, TS-2, both sides of the dorsum of the root wereslightly swollen with rather large openings being observable on their surface.

* In the West Indian manatee the regions on both sides on which the lateral swellings may be present
were not observable, because they were excoriated.
** We described both swellings, dorsal and lateral, as a single swelling in a previous paper (Yamasaki
et al., 1980).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

TONGUES OF THE SIRENIA

131

On the other hand, in the dugong tongue, two rows with deep pits (three onboth sides in DD-1; right, six, and left, seven in DD-2; three on both sides in DD3) were present near both posterior lateral margins which correspond to the posterolateral region of the dorsal swelling in the manatee (Figs 6 and 9). The regions withthe dorsal pits were not elevated. The pits were round, about 1 mm in diameter.
Arranged longitudinally, they opened slightly anteriorly with a separation of about
3 to 4 mm. Small projections could be seen in some pits. Glandular openings,
smaller than those of the pits and surrounded by small elevations, were observedon the dorsum from the posteriormost pit to the epiglottis. Three to seven pits,
the lateral pits, (seven on the right and six on the left in DD-1; six on the right in
DD-2*; three on either side in DD-3) resembling the dorsal pits, were present ina group, a little nearer the dorsal surface adjacent to the anterior region of the palatoglossal arch (Figs 7 and 9). This region was confined to within about 1 cm orless and was not elevated.
In both, manatee and dugong, 20 to 25 round, fiat conspicuous patches wereseen extending on both sides from about the anterior one-fifth of the tongue almost
to the palatoglossal arch in the manatee (Fig. 2), and from the mid-part to near
the arch in the dugong (Fig. 7). The patches were rather white in color in the
fixed state, 1 to 3 mm in diameter, and slightly elevated. One or more small
glandular openings were seen on the surface of some of these patches. Those located at the posterior intermingled regionally with the lateral swelling in the African
manatee, and the lateral pits in the dugong. Small glandular openings were seenin the ventral region of these patches, being particularly abundant on the posterior
part.

Histology
Though the sirenian tongues observed were extremely muscular, adipose tissues was rich in muscular tissues in the posterior area. Superior longitudinal muscle bundles were rather well developed immediately subjacent to the mucous membrane on the dorsum except in the posterior glandular portion. The epithelium of
the dorsum at the spiny apex region was thick, approximately 2 mm or more, but
gradually thinned toward the rear. The epithelium of the dorsum along the midline region of the manatee was relatively thin, with the epithelium becoming thickat the lingual lateral margin. The thickness of the epithelium of the side wall was
about 1 mm. A superficial layer, about 15 µm, of the epithelium, excluding therear part, was cornified. Epithelia of the dorsum and side wall of the dugong were
not thick when compared with those of the manatee. The spines ofsirenians, whichwere strongly cornified filiform papillae, consisted of a cornified superficial epithelium without a conical elevation of the tunica propria. All spines located posterior of the dorsum were thinner than those in the apex region but were almost thesame in histological appearance.
The submucosa beneath the multifossulate swellings in the manatee was oc-* Pits on the left could not be counted, because this area was excoriated.
Sci. Rep. Whales Res. Inst.,
No, 32, 1980

132

YAMASAKI, KOMATSU AND KAMIYA

cupied by a lobulated gland mass mostly composed of mucous glands (Figs 11 -14).
In regions with fossulae, mixed glands which were usually present often opened directly into the fossulae at the relatively upper part (Figs 12 and 14). The glandmasses at the mid-part of the dorsal swelling were approximately 7 mm and 8 mmdeep in the African manatee and West Indian species, respectively. The gland massof the lateral swelling (Figs 15 and 16) reached about half the depth (TS-2) or less(TS-1) of that of the dorsal swelling. The gland masses of both the dorsal and lateralswellings fused with each other. The fossulae were approximately 1 mm in depth.
The inside wall of the fossula was covered with stratified squamous epithelium of
about 50 µm in thickness, without cornification. Secondary papillae were rather
poorly developed in this part. This epithelium contained pale flask-shaped structures or irregularly arranged cell masses with occupied almost the total thicknessof the epithelium (Fig. 12). These were undoubtedly degenerated taste buds, although they were not clearly confirmed due to their poor condition. Well developed pure mucous glands about 6 mm in depth were present from the front of themultifossulate area to the rear. This mucous gland field extended from the anterior part of the palatoglossal arch to the ventral region of the side wall of the tongue.
Capacious ducts were seen in places in the glandular tissues of the tongue (Figs 12
and 13).
On the other hand, in the dugong, pits, both dorsal (Fig. 17) and lateral (Fig.
18), were approximately 3 mm in depth, and surrounded by well developed lobulated pure serous gland masses, clearly distinguishable from the neighboring welldeveloped pure mucous glands (Fig. 17). Wide lumens of gland ducts were observed in these glandular tissues. Since the serous gland mass was fused .to theadjacent gland mass, large serous gland areas existed beneath the pits. The glandmass at the dorsum was approximately 14 mm in depth, and that at the side wall
was about 10 mm deep. Serous glands opened into the pits and the neighboring
mucous glands opened directly onto the dorsum. Some of pits had small projections protruding from their bottoms or walls (Figs 17 and 18). The epithelia of thepits, in which taste buds could be seen, were thin, being about 50 µm in thickness.
Taste buds were found grouped together in some places, especially in the lateralpits (Figs 18 and 19). There seemed to be a larger number of taste buds in thepits of the dugong than in the fossulae of the manatee.
Sections of the round patches on the lateral surfaces of the tongues of manatee(Fig. 20) and dugong (Fig. 21) showed a thinning of the epithelium of approximately 100 to 200 µm. Secondary papillae at the patches were relatively short witha superficial 12 to 20 µm of their epithelium having a tendency towards cornification. The lamina propria of this region contained relatively abundant thick nerve
fiber bundles (Fig. 22). No taste buds were present at the patches. Mucous
glands, comparatively poorly developed in relation to those at the rear part of thedorsum, opened on the surface of some of the patches.
The mucous glands of the rear part of the tongue extended to the palate andpharynx. Those in the dugong were well developed when compared with thosein the manatee. Dugong glands also extended down almost to the end of theSci. Rep. Whales Res. Inst.,
No. 32, 1980

TONGUES OF THE SIRENIA

133

esophagus. Condensations of lymphoid tissue could not be observed at the lingual
root except in one case, African manatee, TS-2, which had some lymphatic nodulelike structures with crypts.
DISCUSSION

The sirenian tongue is difficult to divide strictly into two portions, the body andthe root, due to the lack of a row of vallate papillae, sulcus terminalis, and a traceof foramen caecum, which are features seen at the border between the two portions
in many land mammalian tongues. Therefore, the whole length of the tongue wasmeasured from the apex to the base of the epiglottis. However, data reported byformer investigators have often been unclear as to the posterior measuring point.
Measuring points are necessary in the estimation of data showing the length of
tongues such as those of sirenians, since they have no border marks between the
body and the root as in cetacean tongues (Yamasaki et al., 1976a, 1976b, 1978a,1978b).
There are some ambiguities among previous descriptions on the manatee anddugong tongues. However, the characteristics of the sirenian tongue observed were
1) comparative smallness in relation to body size, 2) slenderness and vertical thickness, 3) absence of sulci on the dorsum, 4) existence of hard, digitiform, cuticularspines in the apex region, 5) existence of large-sized patches on the side wall, 6)presence of peculiar gustatory organs, varied types of foliate and vallate papillae.
Anatomical differences between the two families are summarized and shown intable 2. Items in the table will be compared and discussed.
TABLE 2.

ANATOMICAL DIFFERENCES BETWEEN MANATEE
AND DUGONG TONGUES
manatee

I.
2.

Apex
Spines3.

Dorsum4.

Gustatory organ

5.

Glands of thegustatory organ

round
existing in the apex region
onlysmooth, devoid of papillous
projections
forming dorsal and lateralmultifossulate swellings
mucous, partially mixed

dugongtruncate
extending posteriorly on the bodyof the tongue
full of small elevations with spines
having several pits on dorsum andside wall, forming no swellings
serous, well developed

The outline of the apex of the manatee tongue is rounded. That of the dugong is truncated, but the bifid tip in the dugong as reported by Hill (1945) could
not be observed. Since the apex in the young dugong is round as in the manatee,
age and individual differences may be related to its outline. In young dugong,
Gohar (1957) observed that the cornified tip of the tongue is smooth but that withadvancement in age it develops stiff bristles and becomes rasp-like in appearance.
Our observations on a young dugong, whose spines at the tip were very short, is inapproximate agreement with his descriptions. Drawings of a conspicuous horny
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

134

YAMASAKI, KOMATSU AND KAMIYA

process at the apex pointing anteriad in the dugong tongue were done by Sonntag(1922) and Aoki et al. (1938), and the process was described by the latter.
However, we could not locate such a process at the tip region in the tongues of either family.
One of the great differences between the two families is the appearance of thedorsum. In the dugong, small epithelial elevations, each with a bunch of spines,
spread over the dorsum in contrast with the smoothness of the dorsum of the manatee. Gohar (1957) made very detailed descriptions of the appearance of the dorsum of the tongue of the Red Sea dugong. He stated that no typical circumvallate papillae could be seen, and proposed to call the special type of papillae observed, a bunch of spines on the elevation, "papillae calici-penicilliformes". He looked
upon them as a modified form of the circumvallate papillae. We cannot agree
that the structure composed of special papillae is a modification of the circumvallate papillae, but we assume that it may be a specially arranged filiform papilla,
because of its form, distribution, number and histological features. Vallate papillae have been reported on the posterior part of the dorsum of the manatee by several investigators; Rapp (1857)* in Manatus latirostris, Murie (1870)* in M. americanus,
Gmelin, (1892) in M. latirostris, Weber (1904), species unclear. In the dugong,clustered vallate papillae and rudimentary ones have been reported by Sonntag(1922) and Hill (1945)**, respectively. However, Gudernatsch (1909) observedthat these papillae were absent in sirenian tongues, and we also could not locate
such papilla in our specimens. Gudernatsch (1909) reported "Spiegeln" on thedorsum resembling those on the side wall of M. latirostris and he considered them
to be fungiform papillae. However, in our specimens we could not find such
structures on the dorsum, except for the side wall.
The most characteristic feature of the sirenian tongue is the presence of
peculiar gustatory organs, a multifossulate swelling in the manatee and pits in thedugong, with notable differences in the organs being marked between the two families. Several interpretations have been made by former investigators and there
has been confusioh in terminology among them, especially on the organs of themanatee.
The structures that seem to indicate a dorsal swelling in manatee judging fromthe descriptions, drawings or figures are:
1. a sieve and tonsil-like plate by Rapp (1857) in M. latirostris
2. many fossulate-papillae by Owen (1868)***, species unclear
3. a double set of circumvallate glands by Murie (1870) in M. americanus
4. an anterior tonsil by Gmelin (1892) in M. latirostris (with a drawing)
those seemingly indicating a lateral swelling are:*Rapp (1857) and Murie (1870) might have considered even the patches on the side wall as vallate
papillae, since they indicated that the structures extended to the anterior third of the tongue. This distribution almost corresponds to that of the patches of our specimens.
Hill (1945) reported another group of vallate papillae just anterior to the foremost group in the piton the side wall in the dugong.
Owen (1868) described the structures as extending to the anterior third of the tongue.

**

***

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

TONGUES OF THE SIRENIA

135

a simple lateral gustatory organ by Gmelin (1892) in lvl. latirostris (witha drawing)
2. a large papillary plate by Weber (1904), species unclear
and those probably indicating a continual single swelling, dorsal and lateral, are:
1. a large patch of circumvallate papillae (Mayer's organ)* by Beddard(1897) in lvl. inunguis (with drawings)
2. a compact glandular apparatus with gustatory pits by Gudernatsch (1909)
in lvl. latirostris (with photographs)
3. a large cushion with numerous fissures (lateral organ)** by Sonntag(1922) in lvl. americanus (with a drawing)
However, the descriptions of the pits in the dugong by former investigators
have been clearer than those on the swelling in the manatee, though the pits havebeen written of with various terms: Gudernatsch (1907, 1908), on the dorsal andlateral pits (with photographs); Aoki et al. (1938), dorsal and lateral (with drawings); Hill (1945), dorsal and lateral; Gohar (1957), lateral only (with a drawing);
Nair et al. (1975), lateral only; Husar (1978) dorsal only. Although detailed
observations were made on the gustatory organs in both manatee and dugong
by Gudernatsch (1908, 1909), for some reason, no investigators have referred tohis articles.
Undoubtedly the multifossulate swelling and pits are a variation of the gustatory organs*** formed by lingual papillae. However, it is difficult to conclude
whether they correspond to the vallate or foliate papillae, since neither animal has
these two kinds of papillae, at the corresponding regions as seen in other land mammalian tongues. The classification of the lingual papillae is based on their formand distribution. Since the gustatory organs on the dorsum and on the side wallin sirenian tongues are quite similar to each other morphologically, it would be moreadvisable to clarify the organs by distribution rather than by form. The lateraland dorsal pits of the dugong are clearly distinguishable in their location. As thelateral swelling in the manatee is located in almost the same region as the lateralpits in the dugong, both structures may be considered homologous to each otheras indicated by Gudernatsch (1909). Some former investigators have stated thatstructures corresponding to the lateral swelling (Gmelin, 1892; Weber, 1904; Gudernatsch, 1909) and the lateral pits (Gudernatsch, 1908)**** were primitive typeof the foliate papillae. We agree that the structures belong to the foliate papillae,
but believe it advisable to consider them a varied type of foliate papillae rather than1.

* Mayer's organ is a structure with numerous fissures located on the lateral surface of the elephanttongue. As this structure was first described by Mayer in 1844, it has since been called Mayer's organ inhonor of its discoverer (Forbes, 1879). This structure in the elephant tongue consists of the foliate papillae
themselves (Shimizu et al., 1960). Therefore, the description by which Beddard (1897) regarded circumvallate papillae as Mayer's organ is inadequate.
** Although Sonntag's description is extremely ambiguous in the use of the term lateral organ, we
have judged from his drawing that the organ may have indicated a swelling.
*** Aoki et al. (1938) and Gohar (1957) considered the pits of the dugong as merely glandular openings.
**** Gudernatsch (1908) also used the term" remnants" for the structures.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

136

YAMASAKI, KOMATSU AND KAMIYA

to label them a primitive type of foliate papillae variation. Gudernatsch (1909)
observed that the group of gustatory pits on the side wall (=lateral swelling) in themanatee extended to the dorsum, that is, he believed the pits on the dorsum ( =dorsal swelling) to be a continuation of those on the side wall. We, however, consider the dorsal swelling in the manatee to be an independent structure from thelateral swelling as is also true in the case of the dorsal pits in the dugong, and believethat the structures on the dorsum in both animals may be a variation of the vallate
papillae. In the case of the manatee, the organ is multifossulated and expanded,and swells upwards. In the dugong, on the other hand, the organ grows downwards, with each pit becoming deep instead of being multifossulated. In the manatee, when each swelling, dorsal and lateral, has become well developed with age,the swellings may fuse with each other, and may then be seen as a single continuous
large swelling as shown in Beddard's figure (1897).
There have been no descriptions concerning the existence of taste buds in themanatee, and only Gudernatsch reported numerous ones in the dorsal pits (1907)
and in the lateral ones (1908) in the dugong. However, though the number oftaste buds in the sirenians observed may not be as numerous as those of vegetarianland mammals, they are much more numerous than those in cetaceans (Komatsu
and Yamasaki, 1980).
The region with pits in dugong consists of a well developed serous gland mass,
while that of the swelling in the manatee is composed of a mass of mucous glands,
though partially mixed ones, in agreement with Gudernatsch's descriptions (1908,1909). In the region having taste buds in the fossulae, mixed glands are foundnear the upper part of the fossulae in manatee. Serous fluid may be useful in rinsing the fossula or pit having taste buds, particularly in the case of dugong, which
feed on sea grasses. It is possible that some enzymes contained in serous fluid mayturn the polysaccharide of sea grasses into the small molecules which stimulate thetaste buds. Gudernatsch (1909) considered that the manatee's gustatory organ
glands showed a far simpler grade of development than those in dugong, based on the
poorly developed serous glands in manatee, and stated that marked morphologicaldifferences of the gustatory organs between the animals might depend on some biological factors rather than on the difference in food habits. Since this is a very interesting problem and since adaptation for foods cannot be disregarded, further
studies are expected.
In the dugong, Gohar (1957) observed that mucous glands containing fewer
and smaller serous glands were present under the whole surface of the tongue except for the anterior tip. However, in our observations mucous glands were notpresent in the lingual body except on the lower part of the side wall, but were present at the root, and serous glands were limited to the pit region. Dugong glands,
in particular, are more well developed than those of manatee and extend down almost to the end of the esophagus.
The other characteristic external feature is the presence of patches studded on
the lateral surface of the sirenian tongue. Gudernatsch (1908, 1909) called thesestructures "Spiegeln" in the dugong and manatee, and regarded them as fungiSci. Rep. Whales Res. Inst.,
No. 32, 1980

TONGUES OF THE SIRENIA

137

form papillae. In the dugong, Gohar (1957) also described various sized fungiform papillae, whereas Hill (1945) stated that these were absent. We consider thepatches in sirenians to be large-sized fungiform papillae. Although they have notaste buds, it is supposed that the structures play the role of sensory organs, probably tactile organs.
Rapp (1857) reported tonsils, which were oval plates having numerous openings and showing a sieve-like appearance, on each side in the posterior part of the
tongue in M. latirostris. Gmelin (1892) showed anterior* and posterior tonsils in
his drawing of the same species. However, it is as yet uncertain whether or not
lingual tonsils are present in the sirenian tongue at the corresponding region since
only in one case of African manatee have structures which seem to be poorly developed lingual tonsils with crypts been seen.
ACKNOWLEDGMENTS
We are greatful to Doctors M. Nishiwaki, University of the Ryukyus, Naha,
Okinawa and T. Kasuya, Ocean Research Institute, University of Tokyo, for kindly
supplying the materials for this study. We wish to thank Doctors J. E. Reynolds
III, School of Marine and Atmospheric Science, University of Miami, K. Kubota,
Institute of Stomatognathic Science, Tokyo Medical and Dental University, andK. Takahashi, Department of Anatomy, Sapporo Medical College, who gave us
valuable suggestions and advice for our study. The techincal assistance of Mr S.
Ohtani, Risto-Technical Center, Sapporo Medical College, is also acknowledged.
REFERENCES
AOKI, B., S. TATEISHI, R. TANAKA and K. FuRuHATA, 1938. Anatomical notes on the dugong. Kagaku no
Taiwan (in Japanese), Lab. Comp. Morph. l\1ammal., Zoo[. Inst. Taihoku Imp. Univ., 5: 1-28.
BEDDARD, F. E., 1897. Notes upon the anatomy of a manatee (Manatus inunguis) lately living in the society's
garden. Proc. Zool. Soc., London, pp. 47-53.
FORBES, \V. A., 1879. On the anatomy of the African elephant (Elephas africanus Blum.). Proc. Zool. Soc.,
London, pp. 420-435.
GMELIN, W. 1892. Zur Morphologie der Papilla vallata und foliata. Arch. f. mikr. Anal., 40: 1-28.
Gm1AR, H.A.F., 1957. The Red Sea dugong. Publ. l\llarine Biol. Sta. Chardaqa, 9: 3-49.
GuDERNATSCH, ]. F., 1907. Untitled. Amer. Nat., 41: 665.
GuDERNATSCH, J. F., 1908. Zur Anatomie und Histologie des Verdauungstraktes von Halicore dugong Erxl.
Morph. ]b., 37: 586-613.
GuDERNATSCH, J. F., 1909. Zur Anatomie und Histologie des Verdauungstraktes der Sirenia. II. Die
Zunge von Manatus latirostris Harl. Morph. ]b., 40: 184-194.
HILL, W. W.C.O., 1945. Notes on the dissection of two dugongs. J. Mammal., 26: 153-175.
HusAR, S. L., 1978. Dugong dugon. Mammalian Species, 88: 1-7.
KOMATSU, S. and F. YAMASAKI, 1980. Formation of the pits with taste buds at the lingual root in the striped
dolphin, Stenella coeruleoaha. j. Morph., 164: 107-119.
MAYER, F.J.C., 1844. Uber die Zunge als Geschmacksorgan. Nova Acta Acad. Leop. Carol., 20: 721-748.
MURIE,]., 1870. On the form and stucture of the manatee (Manatus americanus). Tran. Zoo[. Soc. London,

8: 127-202.

* As mentioned above, this seems to be the structure corresponding to our dorsal swelling.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

138

YAMASAKI, KOMATSU AND KAMIYANAIR, R. V., R.S.L. MOHAN and K. S. RAo, 1975. The dugong, Dugong dugon. Cent. Marine Fish. Res. Inst.
Cochin, 26: 1-42.
OWEN, R., 1868. Organ of taste. In: On the anatomy rifvertebrates. Vol. III. Mammals., Longmans, Greenand Co., London, pp. 193-194.
RAPP, W. VON, 1857. Anatomische Untersuchungen tiber Manatus (Lamantin). Jahrh. Ver. vateral. Natkd.
Wurttenburg, Stuttgart, pp. 87-98.
SHIMIZU, Y., T. FUJITA, T. KAMIYA and S. IsoKAWA, 1960. Anatomy of a female Indian elephant with special reference to its visceral organs (in Japanese with English summary). Acta Anat. Nipponica, 35: 261301.
SONNTAG, C. F., 1922. The compartaive anatomy of the tongue of the mammalia. VII. Cetacea, Sirenia
and Ungulata. Proc. Zool. Soc., London, pp. 639-646.
WEBER, M., 1904. Sirenia. In: Die Saugetiere. Verlag von Gustav Fisher, Jena, pp. 727-741.
YAMASAKI, F., H. SATOMI and T. KAMIYA, 1976a. The tongue ofFranciscana (La Plata dolphin), Pontoporia
blainvillei. Okajimas Fol. anal. jap., 53: 77-92.
YAMASAKI, F., H. SATOMI and T. KAMIYA, 1976b. An observation on the papillary projections at the lingual
margin in the striped dolphin. Sci. Rep. Whales Res. Inst., 28: 137-140.
YAMASAKI, F., S. KOMATSU and T. KAMIYA, 1978a. Papillary projections at the lingual margin in the.striped
dolphin, Stenella coeruleoalba, with special reference to their development and regression. J. JY!orph.,
157: 33-48.
YAMASAKI, F., S. KOMATSU and T. KAMIYA, 1978b. Taste buds in the pits at the posterior dorsum of the
tongue of Stenella coeruleoalba. Sci. Rep. Whales Res. Inst., 30: 285-290.
YAMASAKI, F., S. KOMATSU and T. KAMIYA, 1980. An anatomical note on the tongue of dugongs, Dugong
dugon. Proc. Seminar Workshop Dugongs James Cook Univ. in 1979, (in press).

Sci. Rep. Whales Res. Inst.
No. 32, 1980

TONGUES OF THE SIRENIAEXPLANATIONS OF FIGURES
Fig. I. A dorsal view of the tongue of an African manatee (TS-2). The tongue israther slender as a whole, and its tip is rounded. The tip region is covered withmany hard, digitiform, cuticular spines. Dorsal multifossulate swellings, slightly
opened anteriorly, forming a pair may be observed near both posterior lateral
margins of the dorsum. Numerous small openings of mucous glands are visibleon the posterior part of the dorsum. X 1.
Fig. 2. Left side view of TS-2 tongue. The tongue becomes thick posteriorly but
thin at the lingual root. A lateral multifossulate swelling is observed in the anterodorsal region of the palatoglossal arch. Some twenty-five round fiat patches
are present, extending from the anterior fifth of the side wall to near the palatoglossal arch. Small mucous glandular openings are visible from the mid-part tothe arch. X 1.
Fig. 3. A higher magnified view of the left dorsal swelling of TS-2 in figure I.
Roughly twenty-five rather oval, large fossulae are obviously visible on the swelling. Numerous glandular openings, far smaller than the fossulae in diameter, areclearly seen from the posterior region of the swelling to the posterior part of the
tongue. x2.
Fig. 4. A left dorsal swelling of a West Indian manatee (TM-I). The swelling,having many large fossulae, is not as remarkable as that ofTS-2. X2.
Fig. 5. A higher magnified view of the lateral swelling of TS-2 tongue in figure 2,
showing more than ten oval fossulae. Numerous glandular openings, far smaller
than the fossulae in diameter, are observable. x2.
Fig. 6. A dorsal view of the tongue of a dugong (DD-3). The tongue is rather
slender as a whole, with the spine-covered tip region being truncated. Thin, soft
spines extend posteriorly, being especially shaggier on the lateral strips. Smallelevations are seen on the dorsum. A row of dorsal pits can be seen at both posterior margins (arrows). x I.
Fig. 7. Left side view of DD-3 tongue. The body of the tongue strongly bowsanteroposteriorly, with the root being situated at a lower level to the body. Three
lateral pits are observable on the posterior side wall (arrow). About fifteen roundflat patches are present on the mid-part of the side wall. X 1.
Fig. 8. Bunches of spines grow on the small elevations at the anterior dorsum of
the DD-3 tongue. x20.
Fig. 9. A higher magnified view of the dorsal pits on the left side of the dorsum of
DD-3 in figure 6. Small mucous glandular openings can be seen on the posterior
part of the pits. X 2.5.
Fig. 10. A higher magnified view of the lateral pits and patches of figure 7. The
pits and patches vary in size. Small mucous glandular openings are observableon the ventral side of the pits and patches. X 2.5.
Fig. 11. A cross section of both dorsal swellings with fossulae in an African manatee(TS-1). Mixed glands are present in the regions with fossulae, whereas in thearea between both swellings the submucosa is occupied by pure mucous glands.
x5.5.
Fig. 12. A cross section of two fossulae of a dorsal swelling of TS-1. Several fiaskshaped spaces in the epithelium of the side wall of the fossulae may show the remnants of taste buds, the cells of which have sloughed off. Glands are, for the mostpart, mucous in nature but partially mixed, especially in the upper part of thegland mass. Capacious ducts are seen at points in the glandular tissues. The
secondary papillae of the side wall of the fossula are poorly developed. X 15.
Fig. 13. A cross section of a fossula of a dorsal swelling of TS-2. Mucous glands

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

139

YAMASAKI, KOMATSU AND KAMIYA

140

more developed than those of TS-1 are seen but serous glands intermingle partiallyat the bottom of the fossula. The thin epithelium of the inner wall of the fossula
has exfoliated due to its poor condition. X 15.
Fig. 14. A cross section of two fossulae of a dorsal swelling of the West Indian
manatee (TI-I). Well developed glands are mostly mucous in nature, but partially mixed in the upper part of the gland mass. X 15.
Figs 15 and 16. Cross sections of two fossulae (TS-1, Fig. 15) and a fossula (TS2, Fig. 16) of the lateral swelling. The nature of glands is almost the same as thatof the dorsal swelling, but the glands of the lateral swelling are poorly developed
as compared with those of the dorsal swelling. These glands are well developedin TS-2 as compared with those in TS-1. X 15.
Fig. 17. A cross section of a dorsal pit of a dugong (DD-3). Small projections canbe seen in the pit. The pit is surrounded by well developed serous glands (Sg)which are clearly distinguished from mucous glands (Mg). The epithelium of thepit is very thin. X 7.5.
Fig. 18. A cross section of a lateral pit of DD-3. A small projection having taste
buds in its thin epithelium can be seen in the pit surrounded by well developed
serous glands. X 25.
Fig. 19. A more highly magnified view of a part of the projection in figure 18.
Taste buds lie in the thin epithelium of the projection. This figure is taken fromthe area where taste buds are crowded together. X 300.
Fig. 20. A cross section of two patches of TS-2. The epithelium is rather thin andsecondary papillae are poorly developed in the patches as compared with those of
the remainder. Mucous glands and a glandular opening can be seen in the lower
patch. X 15.
Fig. 21. A cross section of a patch of DD-3. The epithelium is rather thin as compared with that of the remainder. Mucous glands can be seen in places. X 15.
Fig. 22. A more highly magnified view of a cross section of a patch of DD-3.
Abundant, rather thick nerve fibers are observable in the submucosa of the patch.

x50.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

tl
l

{
I
J
O
￡・
Z
0861'
JS
！
j・
l
／J
＜
l・
jS~／Vl/. I
l
SJ
/.
l
i
S
./
.

V人
l
¥
/SVl
¥
1
)
0）｛ 1
1
¥
ムVl
i仁INV ns
‑
:
可v
l
V人l

＇~ 2
i

YA
ルI
TSU ANO KA！
,KOMAYAMASAKI

,
.
t
s
1
1
./
s
sRe
e
. Whal
1
/
.Re
i
c
S
,1980
2
.3
o
N

Y八
,KOMATSU A ND KA MI
Y八MASAKI

N
O
&"
t
086('
口S
u ・
／J
＜
I・
/"SJU SJ/VLI
i
i
S
/
・

トI
＋

FINNED PILOT‑O N A MASSIVE STRANDING O F SHORT
λrcHUSGRAY,1846,
PHALA MACRORHY.
CE/
3
WHALE,CLO1
VENEZUELA)SLAND (O N MARGARIT A I。

NOS ANDJOSEPBOUADRIA CASI

,
a
ou
l
h川 e
1ofl
)
l
i
s
r
e
v
i
1
),U1
s
e
t
a
r
b
e
t
r
'(Ve
)
g
o
l
o
o
(
f.
tq
u
c
m
t
n
H
/
c

gebayfrom
ar
donal
ande
r
t
ss
e
twhal
o
l
i
lp
c
c
1
『
自n
，
t
r
o
h
fs
olo
cho
971as
er1
b
o
t
OnOc
‑
. Al
s
巴e
r
et
v
o
r
hmang
it
andybeachw,as)lGuamachc
Ea(tfMargari
ho
t
ou
es
h
t
ns
me
ci
pe
n4and6m. Somes
twee
ngbe
ri
u
s
a
,me
2animalse2
h巴ywer
,t
r
the
e
g
o
t
0km
f2
anceo
t
is
sad
ra
amsuιt
e
r
t
hes
stbyt
hewe
ot
stt
a
o
hec
‑t
ng
o
awnal
edr
wer
.
)
ig.I
F
lGuamache(om E
rf
heCaribbean
aoft
e
ngar
i
r
ghbou
i
ene
h
nt
ei
c
ar
c
em s
e
s
t
o
n
s
e
o
d
s
e
i
c
pe
Thiss
‑
d
an
r
t
ds
e
t
o
u
q
n
o
i
g
℃
1
s
i
h
omt
什
s
an
e
ac
tofCet
s
i
kl
ec
h
nac
)i
1975
e(
e
. VanBr
a
e
S
a
c
i
n
i
m
o
D
,
a
i
c
u
L
.
t
S
n
i
・
‑
s
g
n
i
h
c
at
oupeandc
ldesandGua
o
d
a
b
r
,Ba
s
sonNevigni)aa,Colombiena (Bogotrecho，介om lnd
ama
rnandez‑C. Dr He
t
en
nc
.Vi
t
and S
: San
e
n
o
ez
h
ft
to
s
e
ew
h
nt
si
ng
i
l
c
an
r
t
on)s
ti
a
ommunic
lc
a
r
o
.(
C
oA.
dt
e
t
por
e
r
.
la
u
ns
i
n
ape
r
sonGuaji
alone
er
v
e
)ands
6
6
lyI9
u
nJ
nsi
cime
pe
40s
and(
l
s
si
e
Andr
, Nucleo de
e
t
n
e
i
r
d de O
da
i
s
er
v
i
6n (Ungiv
rnando Cer
r Dr Fe
e
t
, af
s
s
c
l
he
t
er
v
e
I
t
a. I
t
i
r
a
g
r
a
I
!
¥
nl
om moni
eemsunc
es
twhal
lo
dpi
e
inn
f
‑
t
hor
hes
)t
a
t
r
pa
uevaEs
‑
r
a
M
t
u
B
.
s
r
e
t
a
w
c
i
n
a
e
c
o
n
i
,
)
a
c
n
a
l
B
a
l
s
I
(
h
t
r
o
n
e
h
ot
st
le
i
0m
s6
ara
sf
sa
ive
r
ar
st
hebe
,t
ig6n
v
gDrCernidorcc. Alwaysa
s
r
e
t
a
fw
l
he
cs
i
it
fner
oneo
saz
ai
it
gar
‑
p
enJuneandSe
e
w
t
ebe
swouldb
twhaleolipproach p
oa
ng t
i
t
t
i
m
r
e
rp
o
df
o
i
r
pe
‑
k
n
a
l
handzoop
is
noff
o
i
t
e
sadepl
ei
r
e
h
randt
ewarmersahewaternt,whetember

Fig.I
.,
t
ns
s.I
sRe
ヴw/e
l
.I
p
.Re
i
c
S

48
45‑1
,1
,1980
No.32

川町、s
c
e
p
ds
e
d
an
r
t
es
h
ft
Twoo

146

GASINOS AND BOU
TABLE I.

SKULL MEASUREMENTS OF THE STUDIED SPECIMENS
Universidad de Oriente(Margarita)

Measurements

2
3
4
5
6
7
8
9
10
11

12
13
14
15
16
17
18
19
20
21
22
23
24
25
26

Total (condylobasal) length
Rostrum length
Rostrum basal width
Rostrum width 60 mm anterior to base
Rostrum width at middle
Rostrum width at 3/4 of the length
Maximun premaxillae width
Preorbital width
Postorbital width
Zygomatic width
Width of braincase across squamosals
Length temporal fossa
Height temporal fossa
Tip rostrum to the nares
Tip rostrum to the pterygoid bone
Length of upper toothrow (right)
Length of upper toothrow (left)
Number of alveoli of the upper jaw(right)Number of alveoli of the upper jaw(left)
Lower jaw length (left side)
Coronoid length
Length of the lower jaw symphysis
Length of the lower toothrow (right)
Length of the lower toothrow (left)
Number of alveoli of the lower jaw(right)Number of alveoli of the lower jaw(left)

Fundaci6n "La Salle"(Margarita)

2

3

600mm
330
242
244
210
158
220
413
433
439
285
123
135
412
350
120
133
8

550mm
298
218
198
156
92
217
363
384
384
255
104
100
385

122
9

60lmm
291
258
247
218
161
180
414
440
448
274
126
104
397
351
122
119
7

550mm
285
231
210
171
134
194
380
400
408
268
104
Ill
382
335
117
Ill
7

204
836
406
419
265
126
111
389
331
154
154
8

7

9

7

6

8

497mm
147
55
131
130
8

444mm
136
59
113
105
7

8

7

2
567mm
301
240

ton. During those months faunistic elements from the Caribbean corral-ine islands
arrive as far as Margarita. But the present stranding is the only sure reference.
In July 1977, during a trip to Venezuela, one of us (A. C.) had the possibility of studying osteological remains of the 1971 massive stranding, distributed
between the "Centro de Investigaciones Cientificas de la Universidad de Oriente(Nucleo de Nueva Esparta)" and the "Fundacion La Salle", both of them in J\fargarita. Altogether there were remains from five specimens. Measurements of theskulls are given in Table 1.
In the former center, there is a complete mounted skeleton (number 1). Itsvertebral formula is: seven cervical vertebrae (joined), ten dorsal vertebrae, fifteen lumbar vertebrae and twenty three caudal vertebrae. Besides there are twoskulls, one of them (number 3) without lower jaw. In "Fundacion La Salle" twoskulls are kept, both of them without lower jaw, as well.
Skull measurements from Margarita's material have been compared with thoseSci. Rep. Whales Res. Inst.,
No. 32, 1980

STRANDING OF PILOT WHALE

147

IN MM AND PRECENTAGES AGAINST SKULL LENGTH.
L.A.C. (M.N.H.N.)(Paris)

Universidad de Oriente(Margarita)

Fundaci6n"La Salle"(Margarita)

L.A.C.
(M.N.H.N.)(Paris)--------

A-3215
537mm
271
222
227
198
138
195
368

A-3216
560mm
294
206
193
114

395
247
125
94
371
320
136
147
7

349
386
389
260
115
88
370
335
142
137
8

8

8
483mm
144
54
137
149
10

100%
55
40.3
40.6
35
26.3
36.6
68.8
72.1
73. l
47.5
20.5
22.5
68.6
58.3

2

3

100%
54.1
39.6
36
28.3
16.7
39.4
66
69.8
69.8
46.3
18.9
18.1
70

100%
48.4
42.9
41. l
36.2
26.8
29.9
68.8
73.2
74.5
45.6
21
17.3
66.0
58.4
20.3
19.8

20

22.1

22.l

82.8
24.5
9.1
21.8
21.6

80.7
24.7
10.7
20.5
19

100%
51.8
42
38.1
31
24.3
35.27
69
72.7
74.1
48.7
18.9
20.1
69.4
60.9
21. 2
20. l

2

A-3215

A-3216

100%
53
42.3

100%
50.4
41. 3
42.2
36.8
25.7
36.3
68.5

100%
52.5
36.7
34.4

34.21
68
71.6
73.9
46.7
22.2
19.5
68.6
58.3
27.1
27 .1

73.5
46
23.2
17.5
69
59.6
25.3
27.3

20.3
62.3
68.9
69.4
46.4
20.5
15.7
66
59.8
25.3
24.4

86.2
25.7
9.6
24.4
26.6

9

of two skulls coming from Museum Guadeloupe belonging to the collection ofthe "Laboratoire d' Anatomie comparee, Museum National d'Histoire Naturelle"(Paris). True (1889, page 141) says about this that: "a skull in the Paris 1\foseum
from Guadeloupe Island, and which is the basis of Globicephalus guadaloupensis Gray".
The skull figures in van Beneden and Gervais (1880) under the name of Globicephalusintermedius. Gray took it as the type of his species G. guadaloupensis. Unfortunately,
we do not have more details on the skull and it is not possible to say which of thetwo Paris' skulls is the type of the Gray's species.
Thanks are given to Dr Fernando Cervig6n (Universidad de Oriente, Nucleo
de Nueva Esparta, Venezuela) and Dr Jorge Hernandez-Camacho (Inderena,
Bogota, Colombia) for the supplied information. Also to Dr Maite Turell (Department of English Philology, University of Barcelona) for the corrections to the English text. Mr Jose A. Monente supplied generously the picture.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

148

CASINOS AND BOU

The trip to Venezuela of Dr A. Casinos was supported by funds from the"Programa de Cooperaci6n Internacional con Iberoamerica" from the "Ministeriode Educaci6n y Ciencia".
REFERENCES
BENEDEN, P. J. van, and GERVAIS, P., 1868-1879. Osteographie des citaces vivants et fossiles comprenant la description et l'iconographie du systeme dentaire de ces animaux ainsi que des documents relatifs a leur histoire nature/le.
Bertrand, Paris.
BREE, P.J.H. van, 1975. Preliminary list of the Cetaceans of the Southern Caribbean. Studies on the Fauna
of Curacao and other Caribbean Islands, XLVIII: 79-87.
TRUE, F. W., 1889. Contributions to the natural history of the cetaceans: A review of the family Delphinidae. Bull. U.S. nation. Mus., 36: 1-192.

Sci. Rep. Whales Res. Inst.,

No. 32, 1980

A BRIEF REPORT ON THE BEHAVIOR OF COMMERSON'S
DOLPHIN, CEPHALORHYNCHUS COMMERSONII, IN
PATAGONIAN SHORESJORGE F. MERMOZ
Laboratorio de mamiferos Marinos, Museo Argentina de Ciencias Naturales" Bernardino Rivadavia " Buenos Aires, Argentina

ABSTRACT

Data on the behavior and movements of Commerson's dolphins at
Comodoro Rivadavia's harbor were collected as a preliminary step to futurestudies on this cetacean. Evidence on prey-species, calving season and ecological preferences are also given in this general account on what is actuallyknown about the natural history of Cephalorhynchus commersonii and its positionin the harbor's summer community.

Commerson' s dolphin, also known as "Tonina Overa" because of its black andwhite coloration, is a cetacean of about 1. 70 m long and very common in the southwestern Atlantic south of 42°S.
It is also frequent in Chilean waters south of 50°S to Drake passage (Aguayo
and Torres, 1967; Aguayo, 1975). Strange (1972) and Hamilton (1952) comment
its abundance in Malvinas islands and, finally, Angot (1954) reported this species
for Kerguelen islands.
This report, although short is considered of relative importance because it
gives some general new data for this cetacean as well as for imply considerations
that I hope will be of interest for future studies.
Observations were made in the harbor of Comodoro Rivadavia (45°52'S;67°29'W), Chubut province mostly at the end of the southern pier (Fig. 1) or fromthe top of the cliff's that lay just in front of the pebble beach of the harbor.
During most of the time it was possible to track dolphins with the unaided eye
but sometimes 8 X 30 binoculars were necessary.
A Heuler stopwatch with an error of 0.2 sec. was used to clock breathingtimes, and notes were tape recorded or written directly.
Dolphins were tracked during 145 hours in January 1977 and JanuaryFebruary 1980.
The harbor of Comodoro Rivadavia has a mean depth of 5 m and its waters,
although of relatively small volume, contain a high number of species in a moderately populated community at least during part of spring and summer.
Most abundant are schools of gregarious fishes such as silvcrsides (Basilichthyssp. ), Fueguian sardine (Sprattus fueguensis) and southern anchovy (Engraulis anchoita)
all of which are the prey of dolphins, terns (Sterna aff. hirundinacea ), Magellanic
penguins (Spheniscus magellanicus) and shags (Phalacrocorax albiventer).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980, 149-153

150

MERMOZ

There are great kelp beds, especially near the northern pier where Commerson's dolphin appears to be most of the time.
Tidal difference in the area is of about 4-5 m and nothing is known about
how this might influence the movements of dolphins. Another disturbance for thecetaceans are long lasting oil patches left in the harbor by tankers and other ships.
Commerson's dolphin usually swims at moderate speeds, about 6-7 knots.
When feeding they reach higher speeds and perform several kinds of breaches.

(N

G OL FO
SAN

JORGE

/

.I

\

5tms

/

I

t

j

:

I

/

/
j

/

i

J

'

Fig. 1. General view of the harbor area of Comodoro Rivadavia, and its position
in Argentine shores.

Generally, movements of this species seem similar to those described byMoreno (1892) who named it Lagenorhynchusfioweri. From the end of the southernpier it was possible to track with detail this cetacean's slow breathing movements,
which are altered when the animal swims at higher speeds, which it frequently does.
C. commersonii surfaces at an angle of 45°, the tip of the snout first, and then it bends
the head backwards, breathes, and then goes underwater with the body curved sothat immediately after each breath the dorsal fin is above water, then the animal
submerges and the flukes do not come out of the water.
Tracking Commerson's dolphin is very difficult for they usually remain submerged for 15-20 seconds, during which time they swim in a very erratic course,
so it is not easy to tell where they will emerge.
From the top of the cliffs dolphins can be seen swimming at a depth of I or
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

COMMERSON'S DOLPHIN

151

1.5 meters, rarely in straight line.
Dolphins were seen in the harbor every day, mainly at the northern pier andthe kelp beds. They usually search for fish, two or three meters from shore, andthe same distance from the end of the southern pier, where they have been seenat only half a meter when pursuing a school of fish together with Magellanic penguins. These animals also jump very often, making all kinds of breaches. During
field studies in 1980 we saw few of them but in the previous season the maximum
recorded was 65-70 breathes made by 6 dolphins in only 17 minutes on 9 January
1977 (1317 hs, local time).
In general, a group of Commerson's dolphins breathes two or three times andthen they all submerge almost at the same time.
The range of 93 breathing times recorded for several adult dolphins ran from
1 sec. to 1 min. 37 sec. (x: 14.2 sec, SD: 18, 1 sec.) and 54 for calves: from 1 sec.
to 48 sec. (x: 12, 6 sec, SD: 11, 6 sec.).
We recorded 52 interbreathing times from a captive pair of adult dolphinsfor several days in an artificial pool which extended from 3 sec. to 23 sec. with amean of 14.8 sec and a standard deviation of 15.l sec, six hours after their capture, which is in accordance with breathing times recorded in free-living animals.
The simultaneous inmersions of both cetaceans, and the almost imperceptible difference between them when this was not the case, was also seen in the pool.
Inhalation follows exhalation without an intertime. The spout is not visible
even at close range.
Cephalorhynchus commersonii usually swims in groups of 2 to 4 animals althoughschools of 6-7 animals are seen. The greatest group sighted in the harbor of Comodoro Rivadavia was one of about 20 adult dolphins and 11 calves on 25 January
1977 (1500 hs, local time). They also congregate in higher numbers when swimming at the bow of a ship.
This schooling behavior is similar with that described by Baker (1978) for
Cephalorhynchus hectori in New Zealand waters, and mainly by Aguayo (1975) for
C. commersonii.
The dolphins are often in several groups of three or four that move as independent unities for a long time. We cannot say if these groups form part of a larger stock.
Almost nothing is known about the social behavior of this species. On theside of an adult male 1.58 m long captured on February 1980, we found scars distributed in three series; they appear to have been made by another animals of thesame species. This could be the result of "social fighting", probably for females
as suggested by McCann (1974).
Cases of "social facilitation" were seen: several dolphins begin to breach, being followed after few minutes by other animals.
When some Commerson's dolphins were carefully caught for a German zoo,
we could see that other dolphins began to swim slowly near the captive ones.
Acoustic distress signals from those entangled in the net might have attracted theothers. We saw this every time when we succeeded in netting a dolphin.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

152

MERMOZ

It is interesting that no dolphins tried to evade the net by jumping over it.
Every time they seek an exit, they do so underwater, never at the surface. Being
adapted to the aquatic environmet, it is proper that when they feel danger theylook for safety in the water where they can use echolocation. This case is similar
to that of the Pacific tuna-porpoise problem in which Stenella species almost neverescape from the net by breaching over it.
Rather frequently the bibliography mentions several species of cetaceans swimming together with pinnipeds, sea birds etc, but few if any of these references describe interspecific relations between them.
Commerson's dolphins although seen almost every day in the company ofl\fagellanic penguins, terns and shags, never seemed to interact with these species.
For example, on 11 February 1976, during field studies carried out at the San Jose
gulf I sighted a lonely Commerson's dolphin swimming a hundred meters from aschool of three Burmeister's porpoises, Phocoena spinipinnis, without noticing any kindof mutual interest (Wi.irsig et al., 1977).
At Comodoro Rivadavia, Cephalorlrynchus commersonii usually swims close toterns, southern sea lions and Magellanic penguins, but we never could detect interspecific activity. Also, we did not see collaboration between terns and the dolphinsin the capture of schooling fishes as was described by Wi.irsig and Wi.irsig (1979)in dusky dolphins, Lagenorhynchus obscurus and sea birds at the San Jose gulf, where
they feed on southern anchovies, Engraulis anchoita. A probable explanation of thiswould be that in the San Jose gulf dolphins and birds need to "drive" fishes in acompact mass to be able to feed efficiently on them, because of the extension of thegulf. Commerson's dolphins and their prey species live during summer in a relatively restricted area of shallow water where there is no need such collaboration.
This would not be the case in southern, more open waters, where something similar to the situation reported by Wi.irsig and Wi.irsig (op. cit.) may occur.
Little data was gathered on the ecology of C. commersonii.
Harmer (1922) reported krill and squids from a single animal from Puerto
Stanley, Malvinas islands. Although we did not record stomach contents, fromthe behavior of dolphins and the capture of several hundreds of Fueguian sardines(Sprattus fueguensis) after the dolphins feeding activity, we conclude that this fish,probably together with silversides and southern anchovies, are the prey-species of
the Commerson's dolphins in the San Jorge gulf, at least during spring and summer. The distribution of S. fueguensis, on the other hand, is exactly the same asthat of the cetaceans (Lopez, 1963 ).
Dolphins congregate in protected areas such as Comodoro Rivadavia harbor,
the Ria Deseado (Santa Cruz province) and Rio Gallegos (Santa Cruz). We suppose that, as baleen whales do, they look for quiet and protected areas for calving.
Dolphins are seldom seen in wide beaches as, for example, Rada Tilly south of Comodoro Rivadavia and Bahia Solano, north of it, nor are sea birds and sea lions.
They might prefer harbor waters because there it would be easier to feed on schooling fishes where it is not neccesary to drive them, as was said above.
We never saw dolphins feeding at the center of the harbor, only close to theSci. Rep. Whales Res. Inst.,
No. 32, 1980

COMMERSON'S DOLPHIN

153

beach and piers. Wiirsig and Wiirsig (1979) reported the way Lagenorhynchus obscurus feed on E. anchoita at the sea surface, using it as a "wall" to which fishes are
confined. It is very probable that Commerson's dolphins at Comodoro Rivadavia use the beach and piers in the same way as dusky dolphins utilize the sea surface. In the case of L. obscurus, generally several tens of animals drive the fishes,
together with sea birds; but this does not happen with C. commersonii, usually not
more than ten animals feed at a given time.
Commerson's dolphins spend much time swimming in kelp beds, this has beenreported also by Harmer (1922) for Malvinas islands. If the cetaceans profit from
this, we do not know.
Goodall (1978) reported the capture of two pregnant females on the first daysof December, 1977, one of which calf was born on the beach. Another animal(RNP 634) with a near term foetus was captured on 12 December 1977.
In Comodoro Rivadavia's harbor, at the middle of January we begun to see
calves with the adults. The newborn calf is completely brown, as it grows it becomes greyish and then the black and white areas begin to appear, being at firstgray instead of white and darker where it will be black. At the middle of February
1980, we still see calves. A census made on 28 January on the whole harbor area,
showed a minimum of 18 dolphins, two of which were calves, one of them verysmall. This means an adult-calf ratio of 8: 1. A similar census carried out on 25
January 1977 showed a minimum of 50 adults and 11 calves, with a ratio of 4.5: 1.
Goodall (1978) reported 105 animals of her own from Tierra del Fuego, collected mainly between 1974 and 1978, which means a mean stranding of 21 animals
per year. Mitchell (1975) mentioned a report made by James G. Mead on thisspecies in Patagonian shores in which the author suspected an annual mortality ofnear 100 cetaceans in the whole coast.
We have no way of knowing the exact number of animals entangled in fishermen's nets for the moment, so this is the only source of information we have on thematter at present.
Commerson's dolphin is one of most common cetaceans in Patagonian shores.
The first impression we got is that it appears to occupy a very similar ecologic
niche as Lagenorhynchus obscurus north of the San Jose gulf, both animals preying onschooling fish. If these cetaceans intermingle on Argentine shores is something wehope to study in the future.
The calving season takes place in early summer, and it appears that dolphinsprefer quiet areas, although sometimes they are seen in more open waters. This
could be because calves need special water conditions and there might be a preference by adult dolphins for areas in which is easier for them to feed.

REFERENCES
Progress report on small cetacean research in Chile. j. Fish. Res. Bd. Canada, 32 (7):1123-1143.
AGUAYO L., A. and D., TORRES, 1967.
Observaciones sobre mamiferos marinas durante la Vigesmia ComiAGUAYO L., A. 1975.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

154

MERMOZ

sion Antartica Chilena. Rev. Biol. Mar., 13: 1-57.
ANGOT, M., 1954. Observations sur les mammiferes marins de l'archipel de Kerguelen, avec une etudedetaillee de !'elephant de mer Mirounga leonina (L.). Mammalia, 18: 1-111.
BAKER, A. N., 1978. The status of Rector's dolphin, Cephalorhynchus hectori (Van Beneden), in New Zealandwaters. Rep. int. Whal. Comm., 28: 331-334.
GOODALL, R.N.P., 1978. Report on the small cetaceans stranded on the coasts of Tierra de! Fuego. Sci.
Rep. Whales Res. Inst., 30: 197-230.
HAMILTON, S. E., 1952. Cetacea of the Falkland islands. Com. ,(ool. Mus. Hist. Nat. Montevideo, 66 (4): 1-6.
HARMER, S. F., 1922. On Commerson's dolphin and other species of Cephalorhynchus. Proc. ,(ool. Soc.
London, 1922 : 628-638.
LOPEZ, R. B., 1963. Recursos acuaticos vivos. Peces marinos de la Republica Argentina. Eva! Ree. Nat.
Arg., 7: 105-219.
McCANN, C., 1974. Body scarring on cetacea-odontocetes. Sci. Rep. Whales Res. Inst., 26: 145-155.
MITCHELL, E. D., 1975. Porpoise, dolphin and small whale fisheries of the world. Status and problems.
IUCN monograph, 3: 129 pp.
MORENO, F. P. 1892. Noticias sobre algunos cetaceos f6siles y actuales de la Republica Argentina. Rev.
Mus. La Plsta, 1892: 1-20.
STRANGE, I. S., 1972. The Falklands Islands. David & Charles, Devon
WuRsIG, B. and M., WuRsm, 1979. Day and night of the dolphin. Nat. Hist., 88 (3): 61-67.
WuRsIG, M.; B. WuRSIG, and J. F. MERMoz, 1977. Desplazamientos, comportamiento general y un varamiento de la marsopa espinosa, Phocoena spinipinnis, en e1 golfo San Jose (Chubut, Argentina). Physis,

36 (92): 71-79.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

A REVIEW OF FOOD OF BALAENOPTERID WHALESAKITO KAWAMURA
Faculty of Fisheries, Hokkaido University, Hakodate, Hokkaido

ABSTRACT

In order to elucidate what species among so many kind of marine organisms are likely to be consumed largely by the balaenopterid whales, the existing evidence on the food habits of baleen whales is reviewed. To meet withthis primary purpose the report was mainly focussed on to describe qualitative
aspects of food species having been known to date from the notable whaling
grounds over the world rather than documenting quantitative subjects.' One
of interesting facts noticed throughout the contribution was that there exists
fairly intense diversity in the assembly of food species composition by regions
such as; northern hemisphere vs. southern hemisphere, Pacific region vs.
Atlantic region, inshore waters vs. offshore waters, embayed waters vs. open
waters, where the former usually shows more div'ersed complexity than thelatter. The fact however suggests that although the composition of food species locally varies over the various whaling grounds, the food organisms astaxonomical groups are very similar one another even in locally isolated whaling grounds when the food organisms and their assemblies are considered by
the family or genus basis. In this connection many evidences given in the
text may suggest that the balaenopterid whales as a whole may substantially
live on quite simply compositioned forage assembly in comparison with tremendous variety of organisms existing in the marine ecosystems. One of important aspects of the baleen whales food must be found in their characteristics of forming dense swarms, schools, and/or aggregations in the shallower
enough layers to be fed by the whales. The present and past status of larger
baleen whales as the mighty monarch through their evolutional pathways
may entirely depend upon the spatial distribution pattern of possible foodorganisms, i.e. the animal aggregations.

CONTENTS

Introduction .................................................. 156
The balaenopterid whales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7
Baleen plates and feeding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Feeding types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Kind of food organisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Southern Seas .............................................. 166
a. Antarctic and subantarctic .............................. 166
b. South African waters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
c. Australian and New Zealand waters ...................... 174
d. South Pacific and its environs. . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
e. Brazilian waters ........................................ 175
Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 155-197

156

KAWAMURA

Indo-Pacific176
a. Arabian and Malaysian seas ........................... . 176
Northern Seas-North Pacific ............................... . 176
a. North Pacific and Bering Sea ........................... . 176
b. Far Eastern Seas ..................................... . 180
c. Subarctic to subtropics of pelagic Pacific ................. . 182
d. Coastal waters of Japan and East China Sea regions ..... . 184
Northern Seas-North Atlantic ............................... . 186
a. Northeast Atlantic ..................................... . 186
b. Northwest Atlantic ................................... . 189
Summarizing addendum ....................................... . 191
References ................................................... . 193
INTRODUCTION

This contribution firstly prepared in response to the request by the CRC Press Inc.,
U.S. A. under the title, "Diets for Balaenopteridae" as one of the contents should
be included in the "Handbook Series in Nutrition and Food". In December 1979,
however, the publisher informed me that they were unable to include this contribution in the volume to be published near future due to excess holds of contributions
submitted. In response to this situation, submission of article was switched to the
Scientific Reports of the Whales Research Institute No. 32, 1980 by courtesy of Dr Hideo
Omura, the Director of the Whales Research Institute, Tokyo.
Since the main purpose of this article was subjected to describe the known evidence on the food habits of balaenopterid whales, the viewpoint was mainly focussed
on to collect and give qualitative information in a manner of encyclopedia rather
than documenting quantitative and logical discussion. On the other hand, the evidence around food and feeding habits of larger whales from the ecological viewpoint
has been well documented by Nemoto (1959) and later by Gaskin (1976). The
former treated largely the case found in the North Pacific and its environs, while
the latter covered nearly all kind of whale species occurring over the world oceans,and summerized widely scattered evidences into a very comprehensive knowledge
from the viewpoint of evolutional ecology.
At present, it may be considered that the whaling is at its lowest but somewhat
stationary activities being operated in very limited regions, and that the kind offood items taken by baleen whales does not seem to increase so largely as the past
several decades when both whaling ground and whale species changed drasticallyfrom year to year. Since the study by Gaskin (1976), however, some additional
evidence has been known through the study of Bryde's whales from the tropical seas(e.g. Kawamura, 1977), and these are considered to be added as a recently known
evidence to the general knowledge of food habits of baleen whales.
This contribution aims to present simply what kind of organisms are likely to
be taken selectively by the larger whales occurring over the world oceans. Different from treating materials by the organic carbon basis, qualitative knowledge by
species basis must be characteristic and indispensable factors in elucidating theSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

157

structure and function of marine ecosystems since the amount of organisms annually consumed by the larger whales is undoubtedly so enormous as estimated the casein the antarctic krill, Euphausia superba (e.g. Laws, 1978). As the biological environmental factors local food condition strongly relates to the movements and migration of whales (Kellog, 1928; N emoto, 1959; Kawamura, 197 5 ). One of anotherimportant aspects of the dietary habits is the state and condition of stomach contents actually observed in carcasses, which indicate ecological characteristics of food organisms such as individual density, biology of animal aggregation and patchy
distributions, neither of these are hardly known by the conventional net samplings(Omori et al., 1972; Kawamura, 1974; Brodie et al., 1978). In this connection, thebaleen whales and their feeding characteristics as discussed by Klumov (1962) can
be considered really functional and effective 'biological sampler' for marine zooplankters and micronektonic organisms.
Each evidence given in the text may indicates that considerably diversified
food habits are exhibited by locality, seasons, and by each whale species even in ataxon, Balaenopteridae. Ever known facts on the food and feeding ecology may
indicate guide lines which suggest a possibly existing inter- and intraspecies relationships between larger whales and small planktonic or nektonic organisms oflower trophic ladder.
In order to unify the family name of food organisms under the similar forms,
such expression as euphausiids, for example, in the tables quoted elsewhere in the
text was changed into Euphausiacea without notifying this in each corresponding
table.
THE BALAENOPTERID WHALESThe order Cetacea is comprised of two suborders, Mysticeti and Odontoceti. The
former is the baleen or whalebone whales, which includes three taxonomicalfamilies, i.e., Eschrichtiidae, Balaenopteridae, and Balaenidae, while the Odontoceti, the toothed whales are comprised of five families (Table 1).
As it is suggested by the common name, all member of mysticete whales thatare known as. the baleen whales or whalebone whales, are furnished with 'subtriangular horny baleen plates in the upper mandible as the filtering apparatus
instead of tooth in collecting forages although the shape and structure of baleen
plates vary considerably by each family and species. As relatively large mouth
proportion, say, about I /5 long of their total body length suggests, the mysticete
whales could be considered the greatest 'filter-feeders' or 'strainers' among all
animal ever lived on this earth. It is their mouthful row of baleen plates thatmake mysticete whales to be the quite distinct animals both in biological and ecological aspects, especially in gathering their food more powerfully in the aquatic
environment. Of three mysticete families, the Balaenopteridae is the representative taxon which includes so-called great whales or 'rorquals' i. e., the blue, fin(finback), sei, Bryde's, minke whales and humpback whale.
Apart from two another families, the balaenopterid whales are supposedly best
Sci. Rep. Whales Res. Inst.,.No. 32, I 980

KAWAMURA

158

adapted animals to aquatic environments, and distributed widely throughout theworld oceans. Their habitat is usually found in the pelagic waters while twoothers, Balaenidae and Eschrichtiidae, are common in the pelagic to neritic waters.
Sometimes these whale group invade deeply into the inlets and lagoons. Becauseof their well adapted structure to the aquatic environments, the balaenopterid
whales could perhaps have been maintained their largest populations than any othermysticete families in both northern and southern oceans, which undoubtedly due totheir powerful, and consequently more advantageous feeding habits as filter-feeders
in fulfilling the daily nutritional requirements. Because of their gracefully developped but mysterious way of life, the great whales have long attracted scientificinterests, and their dietary habits must have been refered to as one of those mysteries. Inversely, it was unfortunate for the animals of distinct zoological characteristics, that they were doomed later to be the target of modern whaling, but it
was also the beginning of intensive harvest of those giants over the world oceans.
TABLE 1.

THE MEMBER OF MYSTICETI (MYSTACOCETI: BALEEN WHALES)

Scientific name
Family Balaenidae
Balaena mysticetus
Balaena glacialis glacialis
Balaena glacialis australis
Caperea marginata
Family Eschrichtiidae
Eschrichtius robustus
Family Balaenopteridae
Balaenoptera musculus nBalaenoptera physalus
Balaenoptera borealis
Balaenoptera edeni 2lBalaenoptera acutorostrata3l
Megaptera novaeangliae

Common namebowheadnorthern right whale, black right whale, right whale
southern right whale, black right whale, right whale
pygmy right whale
gray whale
blue whale
fin whale
sei whale
Bryde's whale
minke whale
humpback

1) There exists a subspecies, pygmyblue whale, B. musculus brevicauda, which is an endemic species inthe southern ocean (Omura, et al., 1970).
2) The name B. brydei is still valid relating to the identity of two forms of this animal (Omura, 1977).
3) B. bonaerensis has been used for the southern animals. Between B. acutorostrata and B. bonaerensis
there are morphological and biological differences by a magnitude of hardly separable (Ohsumi etal., 1970; Omura, 1975, but see also Doroshenko, 1978). But, Rice (1977) proposes three subspecies,
B. a. acutorostrata, B. a. davidsoni, B. a. bonaerensis.

Because immediate ancestry animals for the mysticete whale are unknown atpresent, it is very hard to suppose that at the beginning of adaptive radiation whatmade the land-dwelling animals driven so as to invade into the aquatic environment
during the Oligocene to Miocene periods. However, it seems to be one of the best
way for the ancestry animals evolving toward the aquatic animals that feed mainlyon the abundant minute crustaceans which undoubtedly had been widely obtainable over the epicontinental shallow seas since the suturing of the supercontinent
Pangaea in the Permo-Triassic periods onward (Schram, 1977), and subsequentSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

159

rapid evolution might perhaps be accelated by the increased marine production by
upwelling of the sea, although the latter is a hypothesis at the present state (Lipps
and Mitchell, 1976).
Although each food item for the balaenopterids may show geographicai andseasonal variations along with the abundance of suitable food even within the same
whale species, the filter-feeder as an adaptation to aquatic environments mustbe perhaps an great advantageous way oflife in competing for food with many kindof another animals. Among so many diversed species composition with the variety of radiation in the phocid seals, the crabeater seal, Lobodon carcinophagus, for example, is the unique animal. The complexed teeth and its general arrangementsin this animal serve as the sieve in collecting minute crustaceans such as Euphausia
superba in the Antarctic waters (Bertram, 1940). The unquestionably larger population size of L. carcinophagus presumably indicates the successful evolutional pathways of this animal through out the order Carnivora (Kawamura, 1972).
The balaenopterid whales are really cosmopolitic animals that undertake alarge scale seasonal migrations of several thousands kilometers, which connect between feeding and breeding grounds while the balaenid whales, Balaena mysticetus,
Balaena glacialis glacialis, E.g. australis and Caperea marginata are considered somewhat
neritic and/orendemically established species. Although the famous gray whale,
Eschrichtius robustus migrates for a great distance of such as between Lower California
and the Arctic Ocean, this animal must be considered really neritic and bottom orbenthos feeders (Rice and Wolman, 1971), which enable them to feed any time andplace enroute their migrations though the major feeding seems to occur in the higharctic regions. The balaenopterid whales as fully developed planktono- and ichthyophagous animals complete their migration by utilizing deposited lipids as anenergetic sources. As it has been pointed out by many workers, the balaenopterids
usually do not or can not feed while they are far outside from the proper feeding
grounds, but recent observations (Gambell et al., 1974; Kawamura, 1975, 1977)
strongly suggest the feeding activity of baleen whales even in the warmer seas.
This again suggests the balaenopterid whales to be the most fully adapted filterfeeders among many others since they can deposit possibly enough amount oflipids
for the nutritional requirements in addition to that used in metabolism during four
to five month stay in the feeding grounds.
BALEEN PLATES AND FEEDING

An adaptation of the balaenoptrid whales as the filter-feeder and, despite their ingenious structure in harvesting those minute planktonic crustaceans, the gross daily
nutritional and energetic requirements are enormous although the energy cost for
locomotion as an aquatic animals would be very smaller than any other terrestrial
animals (Schmidt-Nielsen, 1972; Kawamura, 1975). For instance, the southern
fin whale is estimated to consume only 0.022 kcal/gram body weight/km (Kawamura, 1975). As it is supposed generally in the food items for the balaenopterid
whales, there seems to be difficult in obtaining suitable amount of food over theSci. Rep. Whales Res. Inst.,
No. 32, 1980

160

KAWAMURA

vast oceans except those spacially very limited places so-called the feeding grounds.
The baleen whales, from the beginning of their ancestory evolution towards aquatic animals, are largely dependent upon the organisms occurring with large biomass
and forming dense swarms in the upper subsurface waters (Hjort, 1933). Although
the planktonic crustaceans, small gregarious fish, fish larvae, and some others likesquids may occur widely in the oceans, there are only very limited groups of possible food organisms being actually utilized by the baleen whales. The productivity of oceans shows quite biassed aspect in its distributions. The rich primary
production which finally links to the rich secondary production is usually found in
the colder seas of north and south latitudes higher than 40° latitudes and in the
upwelling regions. The famous feeding ground ever known for baleen whales,
therefore, may be regarded as the most possible and easiest place in locating aggregations and/or schools of prey organisms (Fig. 1). As mentioned before, theFig. I. World whaling grounds for mainly rorquals. The original figure by Mackintosh (1965, Fig. 7) to which recent and some past principal occupations of whaling grounds for sei and Bryde's whales are additionally demonstrated by mesh.
The whaling grounds in the mid-latitude offshore waters indicate the catch placeof Bryde's whales during exploratory fishing (1976/77-1978/79) under scientificpermit (see Kawamura, 1977, 1980; Ohsumi, 1979).

evidence that the baleen whales under breeding migrations rarely feed is certain tosome extent, but this actually seems to be the result due to absolute scarceness of
prey in the warmer seas where they give birth to a calf and mate. Whenever thewhales may encounter to the place where large but local food stocks are available
they undoubtedly prey upon them voraciously (Kawamura, 1977). This suggeststhat poor feeding activity of baleen whales during the breeding migrations does
not seem to be the result of their ecological and physiological characteristics but due
rather simply to the poorer standing stocks of possible food organisms in the breeding grounds or warmer sea regions.
To meet on to their nutritional requirements the baleen whale developed aSci. Rep. Whales Res. Inst.,
No. 32, 1980

161

REVIEW OF FOOD OF BALAENOPTERID WHALES

quite characteristic ·apparatus-the baleen plates or whalebone. The subtriangular baleen plates with fine inner fringes and their curtain like arrangements
in two sets of row on the upper jaw form a fuge filtering or straining apparatus tosieve off some several cubic meters of water containing the aggregation of food organisms. An importance of well developed baleen plates and the row is obvious.
Once the baleen filter was damaged by some reasons such as the infection of parasites (Rice, 1967), the animal may sometime become very poorly nutritioned beingcaused by far little food ingestion due to less effective feeding apparatus.
In the balaenopterid whales the baleen plates usually count 260-400 in number on one of two sides of upper jaw. Each baleen plate is arranged closely one
to the next to form a comb-like row with an intervals of about 0.5-1.3 cm although
TABLE 2.

AVERAGE NUMBER OF BALEEN PLATES IN ONE OF TWO SIDESIN THE NORTH PACIFIC AND ANTARCTIC BALEENWHALES (Nemoto, 1959; Ohsumi et al., 1970)
Blue

Fin

North PacificRange
300-400 300-400
Approximate
360
355
mean
Antarctic and southern hemisphereRange
260-400* 260-480*360
Approximate
320
mean

Bryde's

Littlepiked

Sei

Humpback,

Right

Gray

260-370300

260-300280

320-380340

300-370330

230-260245

130-180160

250-280

261-359289

300-410* 300-370* 220-240*
345* After the data by Discovery research since 1929.
No. of baleen plates
286 +18* /262 cm
14.1 m, Male

45

~

"'c.

12 ~

2"'

c.
"'
c:

"'
"'

E

10 .§.

35

2"'

-a

<;;
..c

8

0

6~

-

c:

<1>

..c

i"' 30

4 'O

::J

z

(ij

>

2~

~
40 60 80 100 120 140 160 180 200 220 240
Distance from the anterior end of baleen row (cm)..E

251.......L-L...L..L-l-L...L..L..l'-:-'-:-'--:C:--:-'-:-7:-'-:~-'-:-:-:-'-:C:-:-'-:-:-::-'-:~'-'

20

Fig. 2. Variation of the number of baleen plates in sei whale. Arrow shows the
spot where maximum length of baleen plates was found (Kawamura, 1974).
(* fringes)
Sci. Rep. Whales Res. Inst.,

No. 32, 1980

KAWAMURA

162

the number of baleen plates and their intervals to the next may vary in details withspecies and the age of animals (Kawamura, 1974). (Table 2, Fig. 2). Usually,
the younger the animal, the more thickly intervaled in baleen plate arrangements.
One of baleen row measurements as found in the southern sei whale is demonstrated
in Fig. 2. The inner fringe of baleen plate is furnished with fine horny bristles(=fringes) of about 3-5 cm long which, by overlapping one to the other, to form
the sieving meshes or 'fibrous mat' as called by Gaskin (1976) that directly concerned with retaining the food organisms on them. The thickness of baleen bristles
Blue (adult)

1--------------1----------4

Blue (young)Fin (adult)
Bryde's (adults, Saldana Bay)
Bryde's (adult, North Pacific)
Bryde's (young, North .Pacific)
Littlepiked (adult)
I Sei (adult)~
Sei (young)Humpback (adult)
Grey
1-W-t Right (young). ()
Fin young1----1_________,
1----1---------t,_1-1----1

1.5

1.0
Diametre (mm)

0·5

0.1

1·B

Fig. 3. Diameters of baleen fringes of baleen whales measured at the center position of baleen plates. Black belts show the ranges of dominant sizes of baleen
fringes. Adult: whales after the sexual maturity, Young: sexually immature andbaleen plates are not chipped (Nemoto, 1959).

6.0
5.0

oEg
• Kawamura(Present study)+Williamson(1970)o Nemoto(1970)

0Bm
N" 4.0

.sro
Q)

~ 3.0
o

Bp

2.0

Bp
Bm
Bp
Be
Bb

Eg

1.0

~
Ba

Mn
Ba

10

15

20

Blue
Fin
Bryde's
Sei
Right
Humpback
Minke

25

Body length(m)Fig. 4. Total baleen filter area in baleen whales (Kawamura, 1974). Both filled
and open triangles show the filter area for the Bryde's whales in the North Pacificand southern oceans respectively (Kawamura, 1978a).

Sci. Rep. Whales Res. Inst,,
No. 32, 1980

REVIEW OF FOOD OF EALAENOPTERID WHALES

163

in terms of their diameter also varies with whale species; then the coarsest filter
among the balaenopterids may be :round in blue whale whilst the finest one in sei
whale (Fig. 3). Further details on the baleen filter can be consulted to Nemoto(1959, 1970), and Kawamura (1974).
As the figures and tables clearly show, the general morphological character offiltering apparatus in the mysticete whales varies from family to family, and from
species to species, although a greater variation may be found in the family Balaenopteridae. The whole structure and the function of filtering apparatus is closely related to those above shown individual characteristics. Among all above mentioned the average along with maximum length of the baleen plates may decides thetotal filter area of animals, which may finally characterize the food and feeding
habits of each whale species (Fig. 4).
Putting together these figures and tables, it is noticed that the balaenopterid
whales as a taxonomical group may be recognized from both eschrichtiids and balaenids by distinguishing relative shorter but finer filtering apparatus. Although
there are several another morphological characteristics relating to the dietary habits of whales, the author believes that the structure of filter itself and its total but
actually functional filter area is among all the most important agents that determine
the feeding habits of each whales species. Further but more general details on thissubject may be consulted to Scoresby (1820), lngebrigtsen (1929), Mackintosh(1965), Slijper (1962), Nemoto (1970), Kawamura (1974) and Gaskin (1976).
FEEDING TYPESThe morphological characteristics of filtering apparatus in baleen whales may
extremely well related to the feeding types and feeding behavior, which largely
determine the kind or the group of principal prey organisms although the latter
again varies with the geographic regions.
Two different feeding types employed in baleen whales have been proposed,(Nemoto, 1959, 1970): i.e., swallowing and skimming types, or swallowers and skimmer (Mitchell, 1974), both of which were perhaps derived from the field observations by lngebrigtsen (1929), although Hjort (1933) noted swallowers as to "play"against the so~called skimmers. His description is so suggestive as to imagine thewhales feeding, and considered worth to be quoted; he (Ingebrigtsen, 1929) describes,"During whaling operations in 1905 Ihad the opportunity of seeing that the humpback is far more intelligent than other species of whale. It employed two methodsof capturing "krill" when the latter was on the surface of the water. One wasto lie on its side on the surface and swim round in a circle at great speed, while itlashed the sea into a foam with flukes and tail and so formed a ring of foam. The
frightened " krill " gathered together in the circle. This done the humpback dived
under the foam-ring and a moment later came up in the centre to fill its open mouthwith "krill" and water, after which it lay on its side, closed its mouth, and thecatch was completed."."The other method'', Ingebrigtsen (1929) continues, "was to go a short disSci. Rep. Whales Res. Inst.,
No. 32, 1980

164

KAWAMURA

tance below the surface of the water, swimming a ring while at the same time it
blew off. The air rose to the surface like a thick wall of air bubbles and theseformed the " net". The "krill" saw this wall of air bubbles, were frightened into the centre, and then the manoeuver of the first method was repeated."" When the whale lay on its side and shut its mouth the rifled belly formed anenormous distended bag before it was contracted and the water pressed out between the whaleboneplates.""When one saw that enormous bag, which was many times larger than thereal mouth from the gullet to the nose one could understand that the humpback,fin-back, sei-whale and blue-whale have the rifled belly from the point of the chinto the middle of the body, solely in order to be able to take in an enormous quantity of water containing food. With the straight jaws and rather straight palatalregion possessed by these 4 whales as compared with the right whales, which have
curved jaws and palatal region, there would be little room for water in the mouth,
if there was taut, smooth blubber under the chin and belly, as its the case with theright whales, the Greenland whale and the North Cape whale." He also describes, " The blue-whale, fin-back and humpback turn over, often with part of the head
above water, when feeding." Very recently Jurasz and Jurasz (1979; observed the
humpbacks in Alaskan waters use three different feeding methods, i.e., lunge feeding, bubblenet feeding, and flick feeding depending on the school mode of available feed. In the lunge feeding there also noticed that the method includes
variations of 'lateral', 'vertical', and 'inverted' lunge feeding.
" The sei-whale, on the contrary, ' skims ' the food. It swims at great speed
through the swarms of copepods, with half open mouth, its head above water tojust behind the nostrils. The copepods rush in with the water and are filtered fromthe water by the whale-bone plates. When a suitable mouthful of copepods has
been taken the whale di~es, shuts its mouth and swallows the food. It is especiallyin the evening and early in the morning, when the copepods are most at the surface,that' skimming' takes place." (Ingebrigtsen, 1929).
The balaenopterids are usually known as to perform a swallowing type feeding.
The whale engulps a mouthful of food containing water by the aid of ventral grooves, and sieve off through the slit of baleen row by giving a pressure on the waterwith its tongue. Then the food organisms retained on the baleen filter are swallowed through throat and oesophagus of several inches across. Recently Gaskin(1976) showed a series of very clear figures offeeding in balaenopterid whales. As
it is noticed in Figs 3 and 4, the sei whale shows rather closer feeding habits to thebalaenid whales with relatively finer baleen bristles and larger filter area, and is considered to demonstrate both skimming and swallowing types of feeding (See also
Table 3). Although the humpbacks as quoted above usually perform the swallowing type feeding, there are clear indication of occasional bottom feeding that is suggested by a significant occurrence of demersal fish and crustaceans along with large
amounts of' fine pebbles' in the stomach (Zenkovich, 1936 cited from Gaskin, 1976).
The minke whale as Norwegian call them "Vaaghval" (=Bay whale) sometimes
enters deeply into the river, inlets and the bay such as the Thames, St. Lawrence,
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALESTABLE 3.

165

FEEDING TYPES IN THE MYSTICETI WHALES(Nemoto, 1970; Mitchell, 1974)

Swallowing type or swallowers
blue whale and pygmy blue whale
fin whale
Bryde's whale
humpback whale
minke whale
Antarctic minke whale
Skimming type or skimmers
right whale (northern and southern right)
Greenland whale (bowhead)pygmy right whale
Skimming and swallowing typesei whale
gray whale
TABLE 4. THE ORDER OF SELECTION OF THE FOOD IN BALEEN WHALES*(Nemoto, 1970) (=shows equivalence, and >shows the dominance to the left)
Blue whale
Fin whale
Bryde's whale
Sei whale
Humpback whale
Minke whale
Right whale

Euphausiacea
Euphausiacea = Copepoda (large)= Gregarious fish >Copepoda(small) >Cephalopoda (squids)
Euphausiacea=Gregarious fish>Copepoda (small)
Copepoda ;;;;;Amphipoda;;;;; Euphausiacea =Swarming
fish=Cephalopoda (squids)
Euphausiacea =Gregarious fish> Demersal fish and crustacean
Swarming fish= Euphausiacea > Copepoda
Copepoda > Euphausiacea >Plank tonic Pteropoda* slightly changed from the original.

freshwater tributaries of Puget Sound (Tomilin, 1967). Pebbles and grand particles in the stomach suggest that the minke as well as the humpbacks feeds atthe bottom occasionally. The balaenids, the right whale group, as known by theirenormously long baleen plates with finest filter meshes but no ventral grooves perform a really way of skimming type of feeding (Scoresby, 1820; Watkins andSchevill, 1976). (Table 3).
The difference in feeding types of whales may characterize the group and/or
the species of food organisms in the order of more preferable feeding. Generally
speaking, the swallowing type of feeding performed by the balaenopterids is considered more suitable for harvesting the larger and faster swimming prey organisms
while the skimming in the near surface water by largely opened mouth would allow to entrap a really small and weak swimmers of planktonic organisms such as
ctenophores, pteropods, chaetognaths and copepods. (Scoresby, 1820; Hjort andRuud, 1929; Watkins and Schevill, 1976). Table 4 gives one of such differences
as having been proposed by Nemoto (1970) where he calls these trends as the orderof selection of the food in baleen whales. These, however, must be regarded as alargely generalized idea, which sometimes seems to be hardly applicable in actual
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

166

cases mostly by the difference of ecologically heterogenious ocean systems to which
the whales come to concentrate and feed. One of typical examples of local differences may be found in the dietary habits of the balaenopterids demonstrated between the Antarctic and the North Pacific feeding grounds (Gaskin, 1976; Nemoto
and Kawamura, 1977).
KIND OF FOOD ORGANISMS
One of well known whales food is the krill, Euphausia superba Dana in the Antarctic Ocean. E. superba predominates over the southern oceans, and is not only
the food of baleen whales but also the food of almost all larger animals, seals, seabirds, fish, squids and perhaps of some benthic animals occurring on the shelf andunderwater ridges. One of comparative study relating this suqject was given by
Salinikov (1953 ). E. superba that is called as the Antarctic krill, certainly build up
those gigantic blue whale of weighing hundred tons and keeps growing the enormous biomass of various whale stocks. Undoubtedly, E. superba can be literally
regarded as the key species in the Antarctic marine ecosystems. (Marr, 1962;
Laws, 1977).
There are, however, many evidences on the food items of baleen whales occurring over the world oceans although the place of events somewhat biassed by
localities since our knowledge on the diet of larger whales largely depends upon thewhaling operations through which we can examine the carcasses of whales, but this isalso restricted by the whaling regulations for locality, seasons and whale species inclusive. Being due to these limited source for the informations, there are vast sea
regions such as Arabian Sea left under complete lack of knowledge concerning thewhales food. It seems, therefore, to be reasonable to describe the evidence on thefood habits of whales by the localities where the whaling of an appreciable extent
have had been and/or have been took place.
Southern Seasa.

Antarctic and Subantarctic

During earlier days of the Antarctic whaling in the South Georgian waters
there had been reported only Euphausia superba and some ' shrimp ' as the whales
food (Hinton, 1925). It might be simply due to the whale species hunted in those
years of the 1920s'-1930s', when the blue whale, Balaenoptera musculus and fin whale,
B. physalus were the main target of whaling. However, several years later, Peters(1938) found fish, Palarepis coregonoides and squid, Onichoteuthis banksii as food of blueand fin whales in addition to E. superba, and more later Peters (1955) added the following species for the Antarctic balaenopterids being based on the German whaling expeditions during 1936/37-1938/39; Euphausia recurva, Thysanoessa macrura, Cyllopus spezialis, Parathemisto gaudichaudii, Eusirus antarcticus, Calanus propinquus, and C.
( = Calanoides) acutus.
In accordance with the change of main harvestable whale species since theSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

167

TABLE 5. STOMACH CONTENTS OF BALEEN WHALES CAUGHT BYJAPANESE PELAGIC WHALING FROM 1961 TO 1965 IN
THE ANTARCTIC (Nemoto, 1970)
Whale species
Food species
Euphausiacea
Euphausiacea & others
Copepoda
Amphipoda
Munida (Decapoda)
Pisces
Cephalopoda (squid)
VacantNo. of whales examined

Blue 1l

Fin

Sei2l

Humpback

Minke

517
4
2
6

16158
18

5936
4
2472
1514
75
31
5
16145
26182

7

88

2
9

10
93

9
76

674
1203

18878
35139

1) mainly subspecies Balaenoptera musculus brevicauda distributed in the lower Antarctic.
2) catch for 1966 season is included.

TABLE 6. FOOD ORGANISMS FOUND IN THE STOMACH OF BALAENOPTERIDWHALES IN THE SOUTHERN OCEANS (Abe, 1957; Nemoto, 1959, 1962, 1970;
Brown, 1968; Kawamura, 1970, 1974; Budylenko, 1978)
Euphausiacea :Copepoda:
Amphipoda:
Decapoda:
Pisces:

Cephalopoda :Pteropoda:
Chaetognatha :Tunicata :Euphausia superba*, E. crystallorophias, E. vallentini*, E. lucens, E. similis*, E.
recurva, E. frigida, E. spinifera, Thysanoessa gregaria,
T. macrura*, T. vicina, Thysanopoda actifrons
Calanus tonsus *, C. simillimus *, Clausocalanus laticeps *, Drepanopus pectinatus *,C. propinquus, C. acutus Calinocalanus macrocarinatus
Parathemisto gaudichaudii f. compressa*, f. bispinosa*, f. intermediate
Munida gregaria*, Penaeus sp.
Gymnospelus nicholsi, Myctophum subasperus, M. punctatum, Scomberesox saurus*,
Notolepis coatsi*, Vinciguerria attenuata*, Notothenia ramsayi, Paralepis sp.,
Tetroganurus curvieri, Lepidotus candatus, Protomyctophum normani, Xenocyttus
nemotoi, Engraulis australis*, Scomber sp.
Octopoda sp., Oegopsida sp., Onychoteuthis banksii
Clione sulcata, C. antarctica
Eukrohnia hamata
Species name is not stated* Important food species.
commencement of modern whaling in the Antarctic onward (blue-fin-humpbacksei/fin-sei-sei/minke-minke) (Kawamura, 1974), a considerable amount of knowledge on whales food have been accumulated. Table 5 is one of the summerized
figures which covers blue, fin, sei, humpback, and minke whales. It may clearly ·be noticed that the blue, fin, and minke whales as typical swallowing type feeder
mainly feed upon euphausiids while sei whale alone shows a stronger preference for
copepods and amphipods in addition to euphausiids, i. e., the former is consideredreally stenophagous and the latter is euryphagous at least in the Antarctic feeding
grounds.
Finding no significant differences in the structure of baleen plate of the North
Atlantic sei whale to that of the Antarctic, Tomilin (1967) considered that the sei
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA

168

whale firstly evolved as the microplanktophagous filter-feeder in the North Atlantic since there had been known only E. superba as the food of sei whale from the Antarctic, and he (Tomilin, 1967) concluded that the sei must be a species appeared
recently in the Antarctic regions. A part of this consideration, however, it does
not seem to be agreeable because the sei actually feeds on so many kind of minutecrustaceans in the Antarctic as well as in the North Atlantic although the evidence
from the palaeozoogeography supports the origin of balaenopterids somewhere in
the North Atlantic regions (Gaskin, 1976).
TABLE 7. KIND OF FOOD ORGANISMS OCCURRED IN THE STOMACHOF SEI, FIN AND PYGMY BLUE WHALES TAKEN IN THE
ENVIRONS OF CROZET ISLANDS (Pervushin, 1968).
Kind of food organisms

Sei

Euphausia frigida
Euphausia vallentini
Calanus propinquus
Calanus acutus
Calanus simillimus
Myctophum punctatum
Onychoteuthis banksii *

+
+
+
+
+
+
+

Fin

Pygmy blue

+

+
+

+

+
+

*Identification by Yu. A. Filippova.
TABLE 8.

FOOD SPECIES OF SEI WHALES IN THE ANTARCTIC (Doi et al., 1967)

SeasonEuphausiacea

Copepoda

MunidaAmphipoda

Pisces1964/65
1965/663688 (5)767 (7)192173 (7)1065

109 (2)1136 (2)

13 (3)
2

Cephalopoda(Squids)5

Number of concurrent food in brackets.

The species of food organisms known to date from the Antarctic region are
as given in Table 6. Looking at the table, we are surprised at the greater
diversity in the composition of diet in balaenopterid whales, and item of foodorganisms turns more diversified features when the adjacent waters to the Antarctic are included. Actually, Budylenko (1978) shown a total of eighty-two foodspecies having been found in the southern sei whales. However, it must be took
in mind that the majority of them are found in sei whale alone, and also it is only
a few food species that actually occurs largely with significant nutritional importance in each individual stomach. The very rare food species are also included in
the table. The subspecies of blue whale, B. musculus brevicauda (pygmy blue whale)(Omura et al., 1970) occurring in the Kerguelen/Crozet waters feeds solely upon
Euphausia vallentini (Nemoto, 1962), but Pervushin (1968) reported E. frigida andsome another organisms (Table 7). However, the food habits of this animal shifts
to E. recurva and/or E. diomedeae in the South African waters (Bannister and Baker,1967).
At present, minke whale, Balaenoptera acutorostrata bonaerensis (Rice, 1977) is
only the harvestable whalebone whales in the Antarctic waters. The stomach conSci. Rep. Whales Res. Inst.,

No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

169

TABLE 9. COMPOSITION OF FOOD ORGANISMS IN THE STOMACHS
OF SOUTHERN SE! AND FIN WHALES DURING THE
ANTARCTIC SEASON, 1969/70 (Kawamura, 1974)
Calanus
tonsusII

ParaCalanus
Drepa- Euphausia Euphausia Euphausia Euphausia themisto
simillimus p notpust
lucensvallentini superha diomedeae gaudiec ina uschaudii----- ----- ----- ----- -----,_....__----- -----

Notolepis
coatsi,_....__~fu~fu~fu~fu~fu~fu~fu~fu~fu

C. tonsus
C. simillimus
Th. vicina
Th. gregaria
Th. sp.
E. lucens
E. vallentini
E. superba
E. similis
E. diomedeae
Th. actifrons
P. gaudichaudii
Penaeus sp.
S. saurus
V. attenuata
N. coatsi

203 1 > 3
52>
2

3

2
10

38

8

1
19
4

8

20

2

I & II : Order of dominancy.
1) Including a mixture with Pseudochirella sp. in the Order II.
2) Including a mixture with a few individuals of P. gaudichaudii, E. vallentini, Th. gregaria and E. hamata
in the Order II.
Note: Finding a few specimens of Parathemisto gaudichaudii at South Georgia, Mackintosh and Wheeler(1929) considered that this species were eaten almost accidentally along with E. superba. More later,
Mackintosh (1942) discussed the food habits of South Georgian baleen whales and stated that P.
gaudichaudii consisted a wholly insignificant part of the diet, and Brown (1968) confirmed this again
in sei whale. But he (Brown, 1968) found two species of myctophids, Electrona (Elampa) subasper andElectrona (Protomyctophum) normani. Table 9, however, strongly demonstrates that the importance of P.
gaudichaudii, copepods and euphausiids other than E. superba in the subantarctic waters.

tents of this animal were consisted of Euphausia superba, E. spinifera and Calanus tonsus(Ohsumi et al., 1970). However, more later study suggests that E. superba may beconsidered to be solely responsible food organisms of the minke whale (Ohsumi,
1979b), and Kawamura and Kikuno (1980) found but a single occurrence of
Thysanoessa macrura out of 381 minke whale stomachs examined.
Among the balaenopterid whales the Bryde's whale alone does not seem toenter into the so-called Antarctic region, and none of information is available atthe present state.
Although there are considerable number of food species in Table 6, the occurrence of different food species largely depends upon the characteristics of their own
zoogeography, and this may be noticed by comparing Tables 7 and 8. For thefilter-feeders one of the important aspects of ecological characteristics is that the
prey organisms should be an aggregate or school forming animals. This has been
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

170

KAWAMURA

deduced from the finding that the stomach contents of each animal are really monotonously or even monospecifically compositioned (Table 9). As it is noticed inTable 9, the stomach contents of whales are usually composed of one or two predominant food species, and those with no asteriks in Table 6 are mostly considered
as a temporal migrants or occasional contaminants when the major food species
were preyed. To look at Tables 6 and 9, it is considered that the most importantand staple food of the southern balaenopterids counts only a several numbers ofplanktonic crustacean species, most of which are the herbivorous and/or omnivorous
creatures. At the sametime, it can be considered from the ecological viewpointthat the marine production and the energetic flows in the Antarctic ecosystem are
structured under relatively simple pathways, a very short circuited flux between
primary production and higher consumers.
TABLE 10. INCIDENCE OF WHALES WITH FOOD IN THE STOMACH IN THE
SOUTH AFRICAN AND ANTARCTIC WATERS (Gambell, 1968)
Fin

Sei

Durban 1l

Cape Province•>
South Georgia
Antarctic pelagic(Area II)

1962
1963
1965
1962
1963
1960-1 to
1964-V
1961-11 &1962-III

Food
present

Empty

33
3
13
122
351

56
79
24
138
281
167
149
16

{M 164F 276
186%
Tota1 feeding
89
82
37
260
632
331
425
202

Food
present Empty

37
4
35
47
56

45
16
5

50}
65
92

%
Total feeding

13

97
129
7
13
30

142
145
12
24
43

32
11
42
46
30

390

653

1043

37

336

72

408

82

11

1) Bannister & Baker (1967).
2) Best (1967).
M and F in the table indicate male and female respectively.

b.

South African waters
The balaenopterid whales visit the South African waters and its environs on
their way to and from the Antarctic feeding grounds. Usually those temperate to
subtropical waters are considered only the migratory passages for the baleen whales
and consequently, very little feeding activity is expected (Mackintosh and Wheeler,
1929). However, in some regions of under the influence by the Agulhas and Benguela Current systems where relatively rich marine production or standing stocksof both planktonic and nektonic animals are expected to form a fishing grounds,
the migrating whales may stay and feed to some extent (Table 10). Because ofits geographical and oceanographical characteristics, even the temperate/tropicalwhale species, the Bryde's may come and concentrate in those offshore and inshore
waters (Best, 1960, 1967). As it is suggested by the annual catching season in Saldanha Bay during the austral winter (chiefly from May to October), the stomachof whales shows what are the nutritional sources during the 'off season' of the Antarctic whaling.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

171

There are rather few available data concerning the dietary habits of whalesin the South African waters except one fine piece by Best (1967), in which a very
comprehensive results are given being based on the investigations during 1962-1963.
By examining a total of 1085 stomachs, Best (1967) demonstrated that about anhalf of the stomachs of baleen whales visited the South African waters of lying in
mid latitudes (36°30'-32°40' S) was repleted considerably with many kind of foodorganisms (Table 11 ). The species of prey by a taxonomical groups found in thewhales stomach were given in Table 12. It is clearly shown in the Table 12 that
TABLE 11. NUMBER OF WHALE STOMACHS EXAMINED AND FEEDING
CONDITION IN fHE SOUTH AFRICAN WATERS (Best, 1967)
1962

Sei
Fin
Bryde'sBlue
Humpback
Minke

1963

A

B

A

B

260
24
30
0

47
45.8
100
0
0
0

632
43
89
2
3

55.4
30.2
83.1

0

O*
0
0

A: Number of whale stomachs examined.
B : Number of stomachs with food in percent figures.
* a few mega!opa larvae was found.
TABLE 12. FREQUENCY OF OCCURRENCE OF ORGANISMS IN BALEENWHALE STOMACHS, DONKERGA T 1962 AND 1963 (combined)(Bannister and Baker, 1967 ; Best, !967)1l
SpeciesEuphausiacea
Euphausia lucens
Euphausia recurva
Euphausia diomedeae
Thysanoessa gregaria
Euphausia spinifera
Nematoscelis microps?
Nematoscelis megalops?
Nyctiphanes capensis
Copepoda
Calanus tonsus
Calanoides carinatus
Clausocalanus arcuicornis forma major
Nannocalanus minor
Euchirella ro strata
Centropages chierchiae
Oncaea media
Corycaeus sp.
Corycaeus speciosus

Sei

Fin

Bryde's

54
33

3
9

18
5

7
3
I

2
2

Pygmy
blue3 >

Humpback3 >

} I

}

72
59
56
14
14
10
3
4

Continued .•.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

172

KAWAMURA
TABLE 12.
Species

Candacia bipinnata
Centropages brachiatus
Scolecithrix danae
Undeuchaeta major
Eucalanus attenuatus
Metridia lucens
Temora turbinata
Pleuromamma borealis
Oncaea venusta?
Paracalanus parvus?
Calanus tenuicornis?
Pisces" Mackerel " 2 lScomberesox saurus
Hygophum hygomi
Myctophum humboldi
Engraulis capensis
Trachurus trachurusSardinops ocellata
Maurolicus muelleri
Lestidium sp.
Scombrid sp.
Amphipoda
Hyperia macrophthalma
Vibilia armata
Brachyscelus rapacoides
B. crusculum
Primno macropa
Plaryscelus serratulus
Phronima semilunata?
Pteropoda
Cavolinia gibbosa
I anthina ianthina
lanthina globosa?
Sryliola subula
Diacria trispinosa
Megalopa larvae
Velella sp.

Sei

Continued.
Fin

Bryde's

Pygmy
blue3l

Humpback 3l

2
2
2
1

2

24
10
10
3
3

2
2

2

14

I

I) Retabulated (data by Best (1967) and Bannister & Baker (1967)).
2) These fish were not examined by a biologist.
3) Data at Durban, 1962-1963 by Bannister & Baker (1967).

the diet of whales is extremely variable in species composition as the evidence foundfrom such a spacially small scale feeding grounds. Especially, the compositions for
copepods, amphipods, and pteropods are of great complexity. The sei feeds mainly upon copepods as well as found in the Antarctic waters while fin and Bryde's feed mostly upon euphausiids though the latter shows more stronger trends of preferSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES173

TABLE 13. PERCENT BY VOLUME OF DIET COMPONENTS IN SEI, BRYDE'S,
AND FIN WHALES IN THE SOUTH AFRICAN WATERS (Best, 1967)
1962

Euphausiacea
Copepoda
Megalopa larvae
PiscesOther organisms
Amphipoda

1963

Sei

Bryde's

Sei

Bryde's

Fin*

64.0
31.0
4.6
0.2

2.5

73.0
23.5
3.0
0.2
0.2

53

94.1
3.8

97.5

47
2.0

"' 1962 and 1963 combined.

TABLE 14.

SPECIES COMPOSITION OF DIET OF BRYDE'S
WHALES OFF DONKERGAT (Best, 1977)

Species

Inshore form
(number of stomachs)

Offshore form
(number of stomachs)

Engraulis capensis
Trachurus trachurusSardinops ocellata
Maurolicus muelleri
Lestidium sp.
Scomberesox saurus
Scombrid sp.
Euphausiacea
Euphausia lucens
Euphausia recurva
Nyctiphanes capensis
Tlo•sanoessa gregaria

25
11
10
0
0

0
0
0
3
3

Pisces

0
0
0
0
1
0

18
5

ing fish diet (Table 13).
Finding new rorqual species, B. brydei, Olsen (1913) reported the two instancesof very unusual food items where sharks up to 2 feet long was found in a stomach,and on another occasion there was found no less than 15 Jackass Penguins, Spheniscus demersus and one Cape Gannet "malagass ", Sula capensis. These are, however,considered to be taken accidentally while the whale was feeding on fish school,
and those stomach contents are presumably spit out later.
More recently, Best (1977) studied more about the Bryde's whale occurringin the same locality and showd a obviously different dietary habits between two
possible allopatric forms; the offshore and inshore forms. His data demonstratethat there exists stronger ichthyophagous form with more coarser baleen filter,
and the other is planktonophagous form .with finer, more sei-whale-like baleenfilter. The former corresponds to :the inshore form and the latter to the offshore
form. Their dietary characteristics which are chiefly due to the difference in occurring water masses are clearly observed in Table 14.
Because of very little whaling operatons in pelagic waters through the tropics,
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

174

KAWAMURA

information around the dietary habits of baleen whales seem to scarcely found.
Land based whaling off Angola, the west coast of Africa was once reported but
there does not seem to exist any appreciable data about the stomach contents ofwhales. Along the Somalian coast both Bryde's and pygmy blue whales feed directly on fish, but species name is unknown (Yukhov, 1969). Another existing few
information suggests that the blue whale along the African coast feed euphausiids,
Nyctiphanes africanus and Euphausia lucens (Mackintosh and Wheeler, 1929), and the
humpbacks may feed the lobster-krill, Munida gregaria (Matthews, 1937), although
there is an indication of non-feeding activity of whales on the whole (Ottestad andRuud, 1936).
The variety and diversity of whales food items around the South African waters
may lead to a consideration that the baleen whales may feed upon those variableorganisms which occur with a larger biomass if not largely but even spacially limited distribution in such a local waters of well outside from their main feeding grounds
in the Antarctic Ocean.

Australian and New Zealand waters
The humpbacks had been the main baleen whale species hunted in the Australian and New Zealand waters. According to Dawbin (1956) the humpbacks on
the northward migration through the New Zealand waters usually feed little. In
some localities, however, there occurs very dense swarms of neritic species of euphausiids such as Nyctiphanes australis, on which the humpbacks feed occasionally.
N. australis is an important food species largely fed by the squid, Nototodarus sloani
sloani around the southern New Zealand waters (Kawakami et al., 1973; Kawakami,1976). In the Cook Strait, New Zealand, humpbacks also take the late larval formof" Glimothea" of galatheid decapods, Munida gregaria, the same prey fed by thebalaenopterids in the Patagonian waters. The Bryde's whale visited Hauraki Gulf
off North Island of New Zealand has been reported to feed on mugilid fishes called'Mullet' but its scientific name is unknown (Gaskin, 1976). Sei whale, on theother hand, feed largely on Calanus tonsus, Clausocalanus laticeps and Parathemisto gaudichaudii around southern New Zealand toward Tasmania (Kawamura, 1974).
In the western Australian waters, the food of humpbacks changes to Euphausia
spinifera and E. hemi.gibba (Dall and Dunstan, 1957). However, Hollis (1939) reported the occurrence of Pseudeuphausia latifrons, herring-like fishes tentatively been
identified as Clupeafimbriata and a few larval stomatopods in the three out of fiftyfive stomach samples of humpback whales taken in Shark Bay off the west coast ofAustralia, although the latter two food items were found in the mouth cavity of afemale animal. The anchovy, Engraulis australis and unknown species of young
mackerel also have been known as main food of Bryde's whales off southern West
Australia. In these waters, however, the baleen whales can be considered feed little during June to October as Hollis (1939) notes, "apparently the whales were notfeeding in this locality ", and empty stomach usually contained only heavy green
flocculent substance or "chunks" of dark green gelatinous material from the squamous epithelium of alimentary tract (Hollis, 1939).
c.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

175

South Pacific and its environs
According to Budylenko (1978), Smirnov (1935) reported that the sei whale
stomachs from the tropical zone of the Pacific contained " fish ". One of few available data is that on the food and feeding habits of the southern Bryde's whale caught
in the Coral Sea and South Pacific regions (Kawamura, 1977, 1980). According to
Kawamura (1977), a total of 120 Bryde's whales (7 in the Coral Sea, and 113 in theSouth Pacific between New Zealand and Fiji Islands) were caught during OctoberNovember, 1976 and found that 75% of the stomachs over the regions contained
food with various state. One of another pelagic catches of the Bryde's whale offsouthern coast of Madagascar, was found that 46.7% of stomachs examined out of
105 were also filled with food. The compotition of stomach contents was completely different from that expected, i. e., they were solely comprised of euphausiids,
E. diomedeae, E. recurva, and Thysanoessa gregaria in the South Pacific animals while
there were only first two species in the Madagascar animals. Table 15 shows oneof results found by Kawamura (1980). It is again noteworthy that the feeding ofbaleen whales may takes place wherever the appropriate prey are found, and sogoes even in the tropical waters of generally poor in the first two stages of productivity.
d.

Brazilian waters
Since the commencement of whaling off Costinha, Brazil in 1910 onward, a
total of about 11,243 balaenopterid whales have been caught until 1974 (William-e.

TABLE 15.

NUMBER OF STOMACHS BY THE KIND OF FOOD
ORGANISMS (Kawamura, 1980).
1976/77
S. Pacific Coral Sea

E. diomedeae
T. gregaria
Euphausia sp. *E. recurva+ T. gregaria
T. gregaria +E. recurva
E. recurva
E. sibogae
P. latifrons
P. latifrons +E. diomedeae
T hysanopoda tricuspidata
Euphausia sp. **E. diomedeae + V. nimbaria
Fish larva***+E. diomedeae
V. nimbaria
Gonostomatid fish

SW IndianNo. 32, 1980

1978/79s. Pacific

E. Indian

5

Total

7
29
2
2

11
38
8
11
9
109
7
29
2
2

4

4

6

10

28

7
8
1
38

51***** Probably E. recurva.
** Probably E. sibogae.
*"'* Larval forms of Myctophiformes.
**** Mixture with one individual of hatchet fish is included.
Sci. Rep. Whales Res. Inst.,

1977/78

3
8
20

1

176

KAWAMURA

son, 1975). The abundant species as found in catch statistics are minke, sei, andhumpbacks yet there is no existing data about the diet of these animals. The
minke whales which have currently been caught about 700 annually do not seem
feed extensively in the Brazilian waters, but a short description stating; "The stomachs of nearly all the whales are empty. A little krill is found in the stomachs ofabout 3% of the whales" (Williamson, 1975). Unfortunately, however, Williamson (1975) did not give the scientific name for this 'krill '. However, feeding ofbaleen whales off tropical Brazilian coast does not seem to take place to an appreciable extent (Paiva and Grangeiro, 1965, 1970).

Indo-PacificArabian and Malaysian seas
Although the Bryde's whale occurs and strands occasionally in the ArabianSea regions (e.g. Roberts, 1970) and Malaysian seas (e.g. Berry et al., 1973), there
seems to exist no information about the dietary habits of whales.
a.

Northern Seas-North PacificNorth Pacific and Bering Sea
The baleen whales occurring in the North Pacific of higher than 50°N andBering Sea regions have been studied extensively along with that in the Antarctica.

Antarctic

North PacificFig. 5. Two deformed schemata for the Eltonian pyramid (Nemoto and Kawamura, 1977).

since there have been heavy exploitation of whale stocks by the factory ship operattions. Since the studies by Ponomareva (1949), Betesheva, (1954, 1955, 1961),
Nemoto (1957, 1959) and several more Russian workers as compiled in Tomilin(196/), the main whaling grounds shifted southward year by year far south down to
20°N in 1972 by an ammendments of whaling regulations and measures, from which
many kind of prey organisms have been introduced (Omori et al., 1972; Kawamura, 1973) In accordance with these general trends, it became rather that clear
an overall composition of whales diet shows considerable complexity covering various taxonomical groups of food organisms over the whole North Pacific and Bering
Sea regions. It can be stressed here that the relative importance of fish and/or
squid diet among many others in the northern seas is hardly comparable to thatin the southern hemisphere. When we see the structure of ecosystem through the
viewpoint of nature in food chain arrangements, for example, the shape of the ElSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

177

tonian pyramids could be expressed two schematically different types (Nemoto and
Kawamura, 1977) as shown in Fig. 5. The proposed schemata demonstrate thatmost of the principal food organisms in the North Pacific are consisted of both omnivorous and carnivorous species while the herbivores largely form main diet of baleen
whales in the southern oceans (Fig. 6). The feeding grounds of baleen whales, whenviewed from the structure of trophic levels in the sea are not substantially equivalent from one to the another.
An overall food items for the North Pacific balaenopterid whales are given in
Table 16. To see the Table 16 along with Fig. 6, it may be noticed that relatively higher occupation of fish and squid in the whales diet in the North Pacific is cha-N

• -/-)'f

40'~~;

•
•

,
tl

I

---

I

140"E

•

\

I

'

II

() 0

®©0 0 0 0 0@ \ID © ®O 0 0 ()@ @ ® (')

~'1-

---

Foshes,,..P.

/·~ Ii)~~ -~ Eup1.~s-----;>lITC

N' <'t\

'·

50

36

120°W

~···- -~~
't f>·(1.~~ecopods. ~~'11~@@~~~()000 f~ ~ ~·() ~ ~ () () () (l Cl @'.) () () ~

)

/

140"

160"

~ Jr-t,.

·".- ~ r--"v' ~~I,.._,

v

180°

160"

140"E

I

!40'

l\~30
26

.. --

'
lso·

160"

160"

12o·w

140"

Fig. 6. Approximate occurrence of food organisms of baleen whales in terms ofpercentage figures in the North Pacific (Nemoto and Kawamura, 1977).
TABLE 16. STOMACH CONTENTS OF BALEEN WHALES CAUGHT BY JAPANESEPELAGIC OPERATIONS FROM 1952 TO 1971* IN THE NORTHPACIFIC (Nemoto and Kawamura, 1977).
Food species
Euphausiacea
Euphausiacea & copepoda
Euphausiacea & others
Copepoda
Copepoda & others
PiscesPisces & others
Cephalopoda (Squids)
Empty
No. of whales examined* Exclusive of data in 1966.
** Including Sergestes similis.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

Blue
97 .6%**

1.1%
1.3%

504
971

Fin

Sei

Bryde's

64.1%**
3.4%
0.3%
25.5%
0.0%
5.0%

12.6%**
0.0%

88 .. 9%

1.7%
10064
29575

82.7%
0.1%
3.4%
0.0%
1.2%
9665
21713

Right

Humpback

100.0%

77.3%
0.6%
3.9%
0.6%

11.1%

82
109

17.2%

0
9

0.3%
150
458

178

KAWAMURA

racteristic yet the importance of both euphausiids and copepods as staple food is unchanged. As it was observed in the South African waters, and possibly in the Antarctic, both Bryde's and humpback whales prefer strongly to feed fish than any
other members of the Balaenopteridae. On the contrary, sei whale that performs
both skimming and swallowing types of feeding shows a considerably wider rangesof selecting the preferable prey organisms.
Each group of prey organisms which represent both the northern North Pacific and the Bering Sea is shown in Table 17.
TABLE 17. FOOD OF THE BALAENOPTERID WHALES IN THE HIGHERLATITUDES OF THE NORTHERN NORTH PACIFIC AND BERINGSEA (Sleptsov, 1955; Nemoto, 1957, 1959; Tomilin,
1967; Kawamura, 1973).
Euphausiacea :Copepoda:
Mysidacea:
Decapoda:
Pisces:

Cephalopoda (Squids):
Pteropoda:

Euphausia pacijica, Thysanoessa inermis, T. longipes, T. spinifera, T. raschii
Ca/anus cristatus, Ca/anus plumchrus, C. finmarchicus, Metridia lucens
Gnathophausia gigas (larva)
Panda/us borealis, Sergestes simillis
Clupea pallasi, Mallotus catervarius, Theragra charchogramma, Colorabis
saira, Pleurogrammus monopterigius, Gadus macrocephalus, Eleginus gracilis,
Sebastodes polispinis, Boreogadus saida
Ommastrephes sloani pacijicus, many others & larva
Limacina sp. Clione sp.

Of those food organisms given in Table 17, the most important euphausiid
species from their frequency occurrence are considered to be Thysanoessa inermis andT. longipes as well as their similar situation in the North Atlantic waters (see Table
25). It is noteworthy that the genus Thysanoessa in the North Pacific and Bering
Sea region is extremely important while the genus Euphausia represents largely inthe southern oceans. In connection with this, the geographically biassed distribution of food species must be considered: i.e., T. inermis predominates in thenorthern side of the Aleutian Chains of especially eastern half of the region ofunder consideration while T. longipes may predominate in the southern side of the
Aleutian Chains. However, the humpbacks in Glacier Bay, Lynn Canal andFrederick Sound, Southeast Alaska were found to feed mainly on Euphausia pacifica,
herring, Clupea /zerengus, and/or capelin, Ma/lotus villosus (Jurasz and Jurasz 1979).
Similar geographical changes may perhaps be found in the copepod food. In
general, the distribution of food organisms shows a considerable locally biassed
concentrations according to the zoogeographical characteristics in distribution
pattern by each prey species, and the idea may be extended further over the almost
all groups of food organisms.
In the coastal waters of higher latitudes in the Bering Sea the fish food becomes
more important than in the pelagic waters. The fin, humpbacks and minke B.
acutorostrata davidsoni (Rice, 1977) in the Gulf of Anadyr, Olyutorsky Bay, Kronotsky
Bay and the Peter the Great Bay, feed chiefly on herring, capelin, saffron cod, andT. inermis. Both humpbacks and finbacks have been reported to feed largely on
Thysanoessa spinifera and its egg masses, and the latter was especially abudant inSci. Rep. Whales Res. Inst.,

No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALESTABLE 18.

Date

179

WEIGHT OF STOMACH CONTENTS OF FIN WHALES TAKEN IN
THE BERING SEA (constructed from Ponomareva, 1949, Table l).

Body
weight(ton)

Food species
Ti

Tr

TI

Cc

Ct

Weight ofstomach contents (kg)Index ofstomachfulness

170.0
212.5
255.0
425.0
127 .1
85.0
68.0
255.0
212.5
85.0
34.0
38.2
63.7
340.0

470
570
690
112
250
270
340
580
560
150
97
120
200
640

68.0
51.0
136.0
85.0
297.5
233.7
170.0
27.5
85.0
25.5
106.2
106.0
170.0
340.0

150
110
36
230
810
530
450
400
230
BO
340
200
450
640

Kommandorsky region

16 VI
16 VI
18 VI
21 VI
25 VI
26 VI
27 VI
28 VI
4 VII
4 VII
5 VII
10 VII
13 VIII
6X

36.0
37.2
36.6
37.B
50.25
31.14
25.76
43.56
37.B
55.38
36.0
28.86
28.86
52.5

14 VI
14 VI
15 VII
19 VII
20 VIII
20 VIII
20 VIII
20 VIII
20 VIII
20 VIII
B IX
B IX
9 IX
9 IX

42.9
43.76
37.2
37.1
36.6
43.56
37.2
31.32
36.6
31.86
30.60
42.24
37.80
52.50

+
+

+
+

+

+

+
+
+
+
+
+
+

+

+

+
+

+
+
+

+

+

+

01,yutorsky Bay

Ti : Thysanoessa inermis,
Calanus plumchrus).

+
+
+
+

Tr: Th. raschii,

+
+
+
+
+
+
+
+
+
+

+
+
+
+

TI: Th. longipes,

Cc : Calanus cristatus,

Ct : Calanus tonsus ( =the humpback stomach (Hollis, 1939). He (Hollis, 1939) believes that over a shortperiod of time the euphausian egg may be of some importance as whales food.
The blue whale were found to feed T. inermis and Nematoscelis megalops both inAvachinskii Bay and Kronotsky Bay (Tomilin, 1967). Another food items which
are absent from the Chukchi Sea animals are sand lance (Ammodytes personatus),
amphipod (Anonyx nugax), euphausiid (Nematoscelis megalops) and copepod (Calanus
cristatus). Ponomareva (1949) reported that both Tftvsanoessa inermis and Th. longipes
were the dominant food assembly in the Olyutorsky and Commandorsky regions.
For these sea regions in 1947, Ponomareva (1949) gives following percentage figureswhere she suggests the increase of copepod food towards autumn:
June: Th. longipes (35%), Th. inermis (30%), Th. raschii (15%), Calanus crisSci. Rep. Whales Res. Inst.,

No. 32, 1980

180

KAWAMURA

tatus (10%) and Euphausia lanei (=E. pacijica) (10%)
July-October: Th. longipes (30%), Th. inermis (33%), Th. raschii (12%) andCalanus cristatus (25%)
In connection with relative occurrence of each food species, there exists one ofvery few indispensable data on the amount of stomach contents which enable us toconsider the actual importance of food species (Table 18).
The knowledge on the Chukchi Sea animal is very limited since there seem tohave been a sporadic whale catches, and the following prey organisms may be seenin the stomachs of humpbacks, but fin whales have been reported to feed T. raschii,
T. inermis, and Eualus gaimardi during August-September (Tomilin, 1967).
Food of the Chukchi Sea humpbacks:
Mysis oculata
Tf?ysanoessa longipes
Pandalus goniurus
Eualus gaimardi
Capelin (Mallotus villosus)
Saffron cod (Eleginus glacilis)
Arctic cod (Boreogadus saida)
The food item for the humpbacks includes considerable number of demersal
fish and crustaceans, which strongly suggests the animal may perform the bottom
feeding in the shallower coastal regions.

b. Far Eastern Seas
Because of the geographical and topographical complexities, there have beenreported a large variety of whales food species from many localities.
In the Kurile region the fin shows a greater variety of food items, and euphausiids, cephalopods and fish having been reported, i.e. Thysanoessa raschii, T. inermis andEuphausia pacijica, Podonema longipes, Ommastrephes sloani pacijica (squid), and fish, Pacific saury (Colorabis saira), anchovy (Engraulisjaponica), and walleye pollock (Theragra
charchogramma) (Betesheva, 1954, 1955), but later she (Betesheva, 1961) added
Calanus tonsus (=C. plumchrus) C. cristatus and Pleurogramma sp. as food of fin whalesin the Kurile region.
Sei whale, on the other hand, feeds largely on copepod, Calanus plumchrus but
feeds also on T. raschii, capelin (Mallotus villosus), sand lance (Ammodytes personatus)and sardine (Sardinella melanosticta) (Zenkovich, 1937). Japanese whaler says thatthe minke whale in the pelagic Okhotsk Sea regions feed exclusively upon the herring (Clupea pallasi) and walleye pollack (Theragra charchogramma). They says thatthe operation of herring fishing boat in those waters is the obvious indications forlocating a fishable concentrations of minke whale. The humpbacks may show asimilar diet to minke whale but have been reported Euphausia pacijica, walleye pollack and even the pink salmon (Oncorhynchus keta) (Tomilin, 1967), while the blue
whale feeds on Calanus cristatus and E. pacijica (Sleptsov, 1955 ).
Russian investigations (Sleptsov, 1955; Klumov, 1963 ), suggest both euphausiids and fish are the most important diet for the baleen whales occurring in the Far
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

181

REVIEW OF FOOD OF BALAENOPTERID WHALESTABLE 19. FOOD OF BALEEN WHALES IN THE PELAGIC AND COASTAL
WATERS IN KURILE REGION DURING 1947-1954 (Sleptsov, 1955)
Whale
species
Fin
Sei
Blue
Minke
Humpback
Total

No. ofstomach Vacantexamined

196
42
15
12
12
277

12
8

20

Ca+
Eu

Eu+
Cep*

PiscesCep+
Pisces

52

23

18

3

7

2

4

2

65

30

64
5
6
6
4
85

10

2

Ca/anus Euphausiacea
2
6

8

18

Cephalopoda(Squids)

6

15
12

5
21

30

3

* Cephalopoda (squid).

TABLE 20. SPECIES COMPOSITION OF FISH DIET OF THE BALAENOPTERIDWHALES IN THE FAR EASTERN SEAS (Sleptsov, 1955; Tomilin, 1967)

Clupea harengus pallasi (herring)Eleginus navaga gracilis (saffron cod)
Osmerus eperlanus dentex (Arctic smelt)lHallotus villosus socialis (capelin)
Theragra chalcogramma (walleye pollock)Ammodites hexapterus hexapterus (A. penonatus ?) (sand lance)
Gadus morhua macrocephalus (Pacific cod)Sebastodes glaucus (rock fish)
Pleurogrammus monopterigius (Atka mackerel)
Sardinops melanosticta (Far eastern sardine)
Oncorhynchus keta (chum salmon)
Boreogadus saida (Arctic cod)
Cololabis saira (Pacific saury)Podonema longipes * (a morid fish)* Laemonema longipes (by K. Amaoka).

Eastern Seas, Okhotsk Sea, Kurile, off eastern Kamchatska and subarctic regionof the coastal Pacific (Table 19). Although Sleptzov (1955) did not mention thespecies name of food crustaceans in Table 19, it may be supposed that Thysanoessa
inermis, T. raschii, Calanus tonsus ( = plumchrus ), C. cristatus and C. pacijicus would represent the stomach of whales. Later investigation (Klumov, 1963), however, revealed the following prey organisms from the balaenopterid whales;
Copepods: Calanus glacialis, Eucalanu~ elongatus, Metridia ochotensis, M. pacijica
Fish: sardine (Sardinops sagax), anchovy (Engraulis mordax, and E. japonica),
capelin (Mallotus villosus)
Squid: Loligo opalescens and Gonatius fabricii
One of characteristics in the dietary habits of whales in the Far Eastern Seas
as suggested in Table 20 is the more extensive diversity in the species compositionof fish diet than in the pelagic waters of the North Pacific and Bering Sea. Occurrence of gregarious fish in the Far Eastern Seas is an important fact as the trophic
environment where even the planktonophagous fin and blue whales feed largely on
those fish schools. The balaenopterids known as the stenophagous animal show a
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

182

KAWAMURA

distinct euryphagous food habits than any other feeding grounds.
TABLE 21. LATITUDINAL CHANGES OF THE DIET COMPOSITION FOR
THE BALAENOPTERID WHALES IN THE NORTH PACIFIC(Nemoto and Kawamura, 1977).
Occurrence of food item in percentage
Latitude (N)300-35°35°-400
400-45°45°-50°500-55°Euphausiacea

Copepoda

Pisces

Cephalopoda(Squid)

14
5
9
23
31.5

55
59
44
37

86
40
23
6.5
8.5

16
17

Decapoda

910.5
6Subarctic to Subtropics of the Pacific regions
As well as the case in the South Pacific the existing informations in the region
are again very scarce but one reports the occurrence of" small fish" from the sei
whale in the tropical Pacific (Smirnov, 1935 cited from Tomilin, 1967). As Fig. 6
demonstrates the diet of baleen whales in the mid to lower latitudes of the North
Pacific may largely be represented by a gregarious fish and copepods though a pelagic shrimp, Sergestes similis occurs largely in the stomachs of fin and sei whales, andthe sergestid shrimp is considered to make up the staple local food over the midlatitudes of the eastern North Pacific (Omori et al., 1973). An overall trends oflatitudinal changes in the dietary composition is given in Table 21. In the lower
latitudes, say, south of 40°N, there also exhibits the changes in occurring whale species from sei to Bryde's whales. In accordance with an increase of Bryde's whaleamong the balaenopterids toward the tropics, the preferable feed item also changesc.

TABLE 22. FOOD ORGANISMS OF SEI WHALE CAUGHT IN THE
SOUTHERN NORTH PACIFIC WHALING GROUND DURING
MAY-AUGUST 1972 (Kawamura, 1973).
Copepoda
Calanus cristatus
Calanus plumchrus
Calanus pacificus
Euphausiacea
Euphausia recurva
Euphausia pacijica
Euphausia diomedeae
Euphausia tenera
Thysanoessa inermis
Thysanoessa spinifera
Nematoscelis difjicilis
Nematoscelis gracilis ll

Decapoda
Sergestes similis
PiscesScomber japonicus
Sardinops melanosticta
Engraulis japonica
Cololabis saira
Maurolicus muelleri
Pseudopentaceros richardsonii
Cephalopoda
Gonatus sp.2l
Berryteuthis anonychus2l1) Identification is doubtful due to ill conditioned specimens.
2) Identification by T. Kubodera.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

183

to some extent. The food composition for sei whale over the subarctic to temperate waters between 30°-50°N of approximately 160°E-l 70°W is given in Table
22, and the recent unpublished data by Kawamura on the stomachs of Bryde's
whale in the lower latitudes revealed the followings as newly known organisms thatmust be added to the dietary list of the balaenopterids (mostly Bryde's) in thesouthern North Pacific regions (Kawamura, 1973);
Fish: Vinciguellia nimbaria
Gasterosteus acreatus acreatus
Scomber tapeinocephala
Pleurogrammus azonus
Tarletonbeania taylori
Ranzania laevis
Am phi pods: hyperiids (larvae)
Squids: Berryteuthis anonychus
Gonatus sp. (young)In the waters around Bonin Islands (about 25°N), the stomachs of sei and
Bryde's whales are mainly consisted of fish and euphausiids. From the investigations through February to May during 1947-1949 along with data from anothersources (Mizue, 1951), Nemoto (1959) reported the following food items:
Euphausiids: Euphausia similis
Euphausia recurva
Fish: Yarrella microcephala (Gonostomatidae)
Myctophum asperum (M yctophidae)
In addition to above mentioned food items, Ranzania rypus (Molidae) and twosternophychid fish, Argyropelecus and Polyipnus sp. were found occasionally (Nishimoto et al., 1952). In the pelagic waters, slender mola, Ranzania laevis is largely
found in stead of R. rypus (Kawamura, unpublished data). It is noteworthy that
there occurs no copepod food in the Bonin Island waters although a possible occurrence of copepod such as Candacia sp. as a constituents of whales food has been
pointed out but no evidence have been reported to date.
In Monterey Bay, California, fin whale was found to contain "enormous
quantity of codfish," and the blue whale in the waters off the port of San Quentin
pursued for the school of sardines and prawns (Scammon, 1874). After mentioning the animalculae, the ' right whale food ' or ' brit ' for bowhead whale in thenorthern waters, Scammon (1874) continues about the minke, "when roaming
about the inland waters of lower latitudes, they often shoot along the shallow borders of the bays in search of the myriads of small fry on which they mainly sustain
themselves ". In the eastern Pacific off Mexican coast, Pacific red crab, Pleuroncodes planipes (Galatheidae) is known as food of sei and blue whales (Matthews,
1938a), but the prey changes to Euphausia pacifica, Thysanoessa spinifera and possibly
Calanus plumchrus in the more northern Pacific coast. The fin whale off Vancouver
Island has been reported to feed Euphausia spinifera, herring, and squid, Gonatusfabricii (Tomilin, 1967). Kellog's description by citing Cornwall (1928) made us
confirm the occurrence of G.fabricii in these waters (Kellog, 1929).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAMURA184

The balaenopterids in the waters off Peruvian coast are believed to take anchovy, Engraulis ringens and some euphausiids but details are unknown (Gaskin,1976). There seems to exist little information concerning baleen whales food in
the Pacific coast along South America. Clarke and Aguayo (1965) found only
' fluid ' in the first and second stomachs of Bryde's whale taken at Caleta Molle,
lquique on the coast of Chile, but Budylenko (1978) suggested that sei whale feeds
but slightly along the Chilean coast.
As it was described in the South African waters, it is noticed in Table 22 that
there are very distinct similarity in the species composition of whales food, i. e., alargely diversed food composition over the tropical to temperate waters throughout the southern and northern hemispheres.

Coastal waters of Japan and East China Sea regions
The region includes the traditionally famous 'Japan Grounds' (Beale, 1839).
Today, it is called Sanriku region situated in the Pacific side of northern Japan, andis the most important fishing ground for the land based whaling. The informationof whales food, however, is somewhat scarce due to few comprehensive study worked out because the catches in coastal whaling are usually very sporadic. Mizue(1951), however, examined the stomachs of some balaenopterid whales as shown in
Table 23. The krill in this region is represented by Euphausia pacifica along withd.

TABLE 23.

Krill
SardineSaury
MackerelRock fish
Squid
Octopus
Empty

FOOD OF BALEEN WHALES IN THE SANRIKU WHALING GROUND,
OFF PACIFIC COAST OF NORTHERN JAPAN (Mizue, 1951).
Blue

Fin

Sei*

Humpback

16

43

253

2

103

11

41

25
1
2
10
1
547

4

* Sei+Bryde's.
less important two Thysanoessa species while it changes to T. inermis and T. longifJes
in far more northern regions adjacent to Hokkaido. Only Calanus pacificus forms
the main copepod food in the Sanriku region though it may change to Calanus
plumchrus in the more northern grounds. Squids are mostly composed of Ommastrephes sloani pacificus on which sei whale feed extensively. Sardine in Table 23 actually means the anchovy, Engraulis japonica. During April to May in the Sanriku
grounds there occurs large school of young sand lance, Ammotfytes personatus, andthe minke whale pursues for them. In accordance with their northward boundmigration along the Pacific coast of Japan, the minke also follows after them up to
the Hokkaido region. Both Engraulis japonicus and Ammotfytes personatus are the mostSci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

185

important food items of minke whale in the coastal waters of Japan (Omura andSakiura, 1956), but Euphausia pacijica must be added in the waters along southwestern Japan Sea. However, the sei during summer largely feed on young mackerel,
Scomber j aponicus.
TABLE 24.

1955

1956

FOOD OF FIN WHALES IN THE EAST CHINA SEA
AND ITS ENVIRONS (Nemoto, 1959).

E. pacifica
Empty
Unknown
E. pacifica
Flying fishll
Blind eei 2>
Empty
Unknown

July

AugustSeptember

October

6
4

22
65
3
20
1

18
76
10
5

7
14

9
63

25
47

2

3
49

19

I) very little quantity.
2) Eptatretus burgeri.

In the Okhotsk Sea coast of Hokkaido, Nemoto (1959) describes both Euphausia pacifica and Thysanoessa inermis with occasional contamination by T. raschii forfin whales caught off Abashiri, Hokkaido. Later observations, however, revealed
that minke whale feeds on E. pacifica and squid, Ommastorephes sloani pacijicus and fin
whale caught far off shore region fed Thysanoessa inermis, which increases its importance gradually toward Sakhalin regions.
In the southern Japan around Kyushu the Bryde's whale frequents its offshore
waters and feeds Euphausia similis during May but gradually shifts to anchovy,
Engraulisjaponica during the summer season. (Nemoto, 1959).
Not so many are known for the East China Sea regions but the following brief
informations (Nemoto, 1959) (Table 24). The Bryde's whale which perhaps thenorthern counter part of the inshore form found in the South African waters (Omura, 1977), feeds mostly on anchovy, E. japonica and three kinds of horse mackerels, Trachurus japonicus, T. declivis, and T. argenteus though the first two are more
prefered by the whales.
In the adjacent waters of Korean coast, the Yellow Sea and Japan Sea, it has
been known that the fin and minke whales feed on euphausiids with occasional occurrence of squid. The corresponding euphausiid species has been believed to be
Euphausia pacijica. There is single record of the fish, Clupanodon punctatus from the fin
whale in the Yellow Sea. (Nemoto, 1959).
The humpbacks in the Ryukyuan waters seems to feed little but a few records
indicate Euphausia similis and Pseudoeuphausia latifrons to be the possible whales food(Nishiwaki, 1959 ).

Sci. Rep. Whales Res. Inst.,

No. 32, 1980

186

KAWAMURA

Northern Seas-North Atlantic

Northeast Atlantic
According to Gaskin (1976), Allen (1916) earlily reported Thysanoessa inermis
as food of North Atlantic humpbacks. As Hjort and Ruud (1929) reviewed on
the fishing and whaling industries in the North Atlantic, the shelf region aroundthe Norwegian Sea and the Greenland Sea has been exposed to the extensive whaling of the blue, fin, sei, and humpback whales since the beginning of this century.
Norwegian whalers have been aware of the importance of food plankton (=krill)abundance in relation to their catch (Hjort and Ruud, 1929). The krill undoubtedly correspond to one of the largest euphausiid species, Meganyctiphanes norvegica
and several others such as Thysanoessa inermis, T. raschii, and T. longicaudata. Since
there also largely occurs copepods and two amphipod species, Themisto libellula andParathemisto oblivia in addition to euphausiids, the latter crustaceans group may also
· likely to be fed by the baleen whales.
Although Hjort and Ruud (1929) did not mention about the whales food in
the Greenland waters, they showed the following items as having been found in
the whales treated at Aukra Island, off the coast of More, Norwegian Sea during
1925-1928. A total of 619 baleen whales were examined (366 fin, 252 sei and 1blue) and found the enormous amount of plankton food among many animals during January-August.
The food items found were:
1. Herrings (especially ' large ' or spring herrings)
2. Euphausiids (krill)a. " Stor-krill" (large krill) corresponds to Meganyctiphanes norvegicab. " Smaa-krill" (small krill) mostly Tl!Jsanoessa inermis
3. Rod-aate " (copepods) mainly consisted of Calanus finmarchicus
According to Hjort and Ruud (1929), Sars (1874) states that the food of blue
whale in the waters of Finmarken was exclusively comprised of " loddle " or capelin, Mallotus villosus and Thysanopoda ( = Thysanoessa) inermis, while fin whales follow
after spawning shoals of capelin (M. villosus) off the coast of Finmark (Jonsgard,1966). The herring does not seem to be fed by the blue whale but both humpback
and minke take herring largely in this waters. In the Davis Strait, the fin feeds
herring and Thysanoessa inermis during winter (January-March) but it changes tosmaller euphausiids and Calanus finmarchicus in the spring (April-May) and thenshifts to Meganyctiphanes norvegica from May to August (Tomilin, 1967). In addition
to above mentioned food items, followings are the fish food of greater importancein the North Atlantic; cod, mackerel, sand lance, dog fish, whiting, and pollock.
Although the food item may varies with season and whale species, capelin, M. villosus must be an another important whales food in the Finmarken waters.
One of characteristics of the marine distribution in the North Atlantic is theoccurrence of very small copepod called " swamps " (Millais, 1973 ), Temora longicornis as food of baleen whales as well as the food of herrings in the Irelandic waters(Collet, 1886; Millais, 1906; Herdman, 1971), and in the Newfoundland watersa.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

187

REVIEW OF FOOD OF BALAENOPTERID WHALESTABLE 25. STOMACH CONDITIONS OF MINKE WHALE AROUND THE
NORWEGIAN WATERS (constructed from Jonsgard, 1951).
Stomach contents
RegionNo. of abs.

Area

ArcticNorwegianwatersBarentz Sea

Lofoten
Vestraalen
Helgoland

Empty

Fish 1>

94
105

2
333>

14
56

(753>+20)
(9)
(1)
199

(33 3>)(27 3>)

(73>)

35

70

(77)

Krill+ Copepod/Krill +Fish

Milk

78 2>
143>

13)

93

(73>)

(13>)

(16)

1•>

1) Cod, "skrei "2) Krill, Thysanoessa inermis
3) Vestfjord proper4) Calf, 16 feet 10 inches
TABLE 26.

RegionFOOD OF MINKE WHALE IN THE NORWEGIAN COASTAL
WATERS (constructed from Jonsgard, 195!1>)

Area

No.
of
abs.

Herring

Vestfjord

R0st

20

12

Vesteraalen

Outside99Arctic2 >Bear Island

HerCapering+!inothersHaddock

Cod

3+

Spitz berg en+

Barentz Sea

+

+
+

Other
species

Remarks

5

0-group herring"musse"I-group herring"bladsild"especially inautumnLarge herring,small codI-group herring" bladsild " large
haddock

1) Jonsgard notes that "the truth is evidently that minke whales prefer krill when this animal abounds,
but they resort to a great variety of shoaling fishes wherever these are met with."
2) No actual number of animals examined is stated.

where blue whale takes this species (Tomilin, 1967). T. longicornis have never beenfound as the whales food over any another whaling grounds in the world. In addition to crustaceans, there have been reported the pteropod molluscus which is considered to be Clione limacina and/or Limacina helicina. (Hjort and Ruud, 1929;
Peters, 1938).
To see these food items by each whale species, it can be said that the sei inthe coastal banks and slopes region feeds almost exclusively on Calanus .finmarchicus,
while the fin feeds herrings, Calanus .finmarchicus and two euphausiid species above
mentioned. The abundance of migrating whales into the whaling grounds in Moreregion is closely related to the abundance of these food organisms, i. e., there can be
expected richer whale migrations into the whaling ground in the years of moreabundant food distribution. The whales food as mentioned above may changes by
whale species and also by the seasons. The fin whales during January-March,
Sci. Rep. Whales Res. Inst.,

No. 32, 1980

188

KAWAMURA

for instance, feed either herrings or Thysanoessa species, while they feed Calanus finmarchicus and T. inermis in April towards early May. During August, the seasonof" summer fishing" (Hjort and Ruud, 1929) as they call, the fin survives exclusively on Meganyctiphanes norvegica.
According to Christensen (1975) the food items of the North Atlantic minke
whales B. acutorostrata acutorostrata (Rice, 1977) in the Barents Sea and off East
Greenland were largely consisted of capelin, but they changed to sandeels andkrill, Thysanoessa inermis in the waters off West Greenland. One of interesting
evidensces found in the North Atlantic to the Arctic waters is greater variabledietary items of minke whale by season and localitites as shown in Tables 25 and 26.
The minke in these waters, however, feeds generally on herring in spring along
the Norwegian coast, while it feeds mainly on capelin during summer in thenorthern waters along with gadoid fishes such as cod, whiting, and coalfish (Jonsgard, 1951). Although there may exist some confusion regarding the identity offood animals, Jonsgard (1951) gave fourteen possible fish species as the food ofminke whale; herring, sprat, mackerel, cod, coalfish, haddock, ling, pollock, whiting, Norway haddock, catfish, salmon, capelin and sand-eel (Table 27). He (1951)
TABLE 27. POSSIBLE FISH FOOD FOR THE NORTH ATLANTIC MINKE WHALES(Jonsgard, 1951). THE SCIENTIFIC NAME CORRESPONDING TO THE COMMONNAME WAS BASED ON WHEELER (1969), LYTHGOE (1971) and UNESCO (1973)
Common name
SalmonCapelin
Herring
Mackerel
Sand lance
Cod
Coal fish
Haddock
Norway haddock
Pollock
Whiting
Sprat
Ling
Catfish (Wolf fish)
Dog fish

Scientific name

Salmo salar
Mallotus villosus*
Clupea harengus*
Scomber scombrus
Gymnammoqytes cicerellus
Gadus morhua*
Pollachius virens ( = Gadus virens)
Melanogrammus aeglefinus (=G. aeglefinus)
Sebastes marinus
Pollachius pollachius
Merlangius merlangius*
Sprattus sprattus*
Molva molva
Anarhichas lupus*
S!J1liorhinus caniculus* UNESCO (1973) recommends trinominal nomenclature for these fishes.
also :suggested the occurrence of copepods (Calanus), krill (Euphausiacea), small
shrimp or ' aate ', and even mature cod ' skrei ' and big gadoid fishes. Gravel andstones up to the size of an egg are occasionally found (Jonsgard, 1951).
In the region of southern slopes of the Norwegian Sea-the Norway-Shetland-Faroe Island area-three euphausiids, M. norvegica, T. inermis and T. longicaudata occur with larger quantity. Although Hjort and Ruud (1929) did not show
the whales food in this region, it may be supposed that the fin whale occurring off
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

189

Faroe Island feeds above three euphausiids. The similar dietary situation could be
supposed to the northern slopes of the Norwegian waters.
In the Icelandic waters there has been reported an appreciable number of theblue, fin, sei and humpback whales come to concentrate and feed. The coincidence of their concentration with the pronounced abundance of krill distribution
suggests the possible whales food to be Thysanoessa inermis and Meganyctiphanes norvegica. Reviewing the fin whale fishery off the West Coast of Iceland, R0rvik et al.
(1976) described, "In all the investigated years, 1925-1928, the fin whales were
eating herring, small krill ( Thysanoessa inermis) or copepods, mainly Ca/anus finmarchicus, from the middle ofJanuary to the early part of May ". From May to the middle of August, " .... the fin were feeding exclusively on the large krill, Meganyctiphanes norvegica ". However, the greater part of the fin whales food seems to change
to capelin, M. villosus toward the eastern Greenland. (Jonsgard and Christensen,
1968).
Towards south closer to the temperate North Atlantic there seems to increasein the variety of fish food among many others, especially the fish belonging togadoids, clupeids and scombroids and they may become important particularly
m the coastal waters (Gaskin, 1976).

b.

Northwest Atlantic
From temperate to subarctic waters along the eastern coast of North America
there exists one of two places where the large number of the balaenopterid whales
come to concentrate and feed during the warmer season. Composition of the whales
food in this region is generally comprised of similar animal communities to thatknown in the northeastern Atlantic waters, where copepods, euphausiids, and gregarious fish predominate in the whales stomachs. In the region of Bay of Fundy,
copepods, euphausiids, herring and mackerel are said to begin rise into the surface
during the summer, and the fin whale being attracted to those possible prey organisms begin to gather in the region (Gaskin, 1976). Although the diet of baleen
whales may generally go similar way over the whole North Atlantic, yet there seems to exist qualitative differences from localities and seasons.
The baleen whales food as revealed by the Canadian workers gives a comprehensive knowledge about whales food (Mitchell, 1974). By examining both fin andsei whales at Blandford, Nova Scotia, and sei at Dildo and Williamsport, Newfoundland between 1965 and 1972, Mitchell (1974) found the following food species: krill, copepods, sand lance, mackerel, herring, squid and ' fish ' for the Nova
Scotian animals, whilst the food in Newfoundland animals was composed of capelin, sand lance, lantern fish, krill, white fish, and cod. Although Mitchell. (1974)
did not give the scientific name for copepods and krill, they were perhaps comprised of Thysanoessa inermis, Meganyctiphanes norvegica, Ca/anus finmarchicus, and Temora
longicornis. One of distinct differences existing between two locations are the complete lack of capelin from the diet in the Nova Scotian animals. The capelin comprises the main diet of fin whales of mostly 80-100% through May to Novemberin the Newfoundland. On the other hand, the same whale species in the Nova
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

190

KAWAMURA

Scotian waters feed largely on krill possibly be comprised of M. norvegica and several Thysanoessa euphausiids through May to November in more than 80% ofanimals, but the sei alone feeds largely on copepods (60-80%) between June andOctober. Brodie et al. (1978) reports that of 67 stomachs of fin whale taken in theNova Scotian waters 63 were full of krill, Meganyctiphanes norvegica, three contained
copepods and one was full of young herring. The importance of krill, M. norvegica
as food of fin whale is clear in the northwestern Atlantic region. To see the whales
food as shown in the two above localities, it is observed that both krill and copepods
are the most important food items in the Nova Scotian waters. Both sand lance
and mackerel are also fed by the fin whale but none of them by the sei whale.

Fin&

Bryde'sFig. 7. Schematic food web showing predation by "swallowing" and "skimming" baleen whales on main food sources (Mitchell, 1974).

Lantern fish and white fish may come to the next importance in the Newfoundland
especially in October through November. The humpback whales taken at Nova
Scotia (Blandford) and Newfoundland (Williams port and Dildo) were found to feed
capelin, sand lance, white fish, mackerel and krill (Mitchell, 1973). Of those prey
items, both capelin and krill are considered to be the main diet of humpbacks in
the Canadian Atlantic waters. Generally, it can be considered that there exists a
considerably different feeding grounds in the northwestern Atlantic region whereas
its expansion is spacially very limited. One of such feeding grounds may largely
depends upon the planktonic crustaceans in the formation of feeding ground while
the another one depends upon the small to medium sized gregarious fish species(Fig. 7).
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

191

Summerizing addendum
In summerizing the review, it may be said that although the main subject of
this article was confined to deal with the diet of" balaenopterid whales ", the foodof the balaenids-right, bowhead, and pygmy right whales as stenophagous animal
is generally consisted of very similar food items with that found in the balaenopterids while the eschrichtiid whale alone shows quite different aspects from the above
two taxonomical groups. As mentioned in the morphological characteristics of thebaleen filter, the balaenid whales obviously perform "skimming" and feed preferably on smaller, weak powered swimmers of crustaceans such as copepods even insuch waters of rich euphausiid distributions as known in the the southern oceans,
where an another problem-competion for food between southern right and sei
whales may arise. (Kawamura, 1978b).
The bowhead, however, by their extraordinal biological, ecological, and zoogeographical distinctions, feeds rather complicated prey organisms. In his marverous book, "An Account of the Arctic Regions'', Scoresby (1820) demonstrated a fantastic plate showing the food organisms of bowhead whales, in which he introduced;
actiniae, cliones, sepiae, medusae, cancri and helices. He also added squllae or shrimp
from the different observations. To see Scoresby's plate XVI (Scoresby, 1820),
several additional food organisms may be observed; that is, two kinds of chaetognaths and a kind of both planktonic tunicates possibly belong to Oikopleura and gammarid amphipods. Although it is difficult to interprete each organisms from the
Scoresby's descriptions, Hjort and Ruud (1929) identified some groups of whales
food being based on the figures in the Scoresby's plate and found:1. The four ctenophores: Beroe cucumis, Pleurobrachia pileus, Mertensia ovum,
and Bolina septentrionalis
2. The two pteropods: Clione limacina and Limacia helicina
3. The two or three crustaceans: Hymenodora glacialis, Calanus hyperboreus,and possibly Themisto libellula
These organisms, however, seem to be unlikely as the staple food of bowhead,
and it was concluded later that their main food in the Atlantic Arctic region must
be a copepod, Calanus .finmarchicus as illustrated very likely in the Scoresby's plate(Ruud, 1937). Euphausiids may also be included in the diet of Atlantic bowead
whale. In the Alaskan waters the bowhead feeds copepods, Calanus glacialis andC. hyperboreus during their Bering Sea/Chukchi Sea migrations although the benthic
gammarids are likely to be taken supplementary. Very recently, Lowry et al.
(1978) examined two female bowhead whales caught in the vicinity of Point Barrow, Alaska. The stomach contents analysis revealed that the Alaskan bowhead
feeds mainly on Tfrysanoessa raschii, gammarid amphipods, Gammarus zaddachi, Acanthostepheia behringiensis, Monoculoides zernovi, and Rozinante fragilis, and hyperiid amphipod, Parathemisto libellula. Of those above mentioned food species, T. raschii
made up 90.3% of the total volume. Lowry et al. (1978) also found an unidentifiable carapace of shrimp and even a small pebble in the stomach. According toSergeant and Hoek (1974a), however, "nothing is yet known of the nature of thefood of bowheads " in the Franklin Bay region, Canadian Arctic, but they (SerSci. Rep. Whales Res. Inst.,
No. 32, 1980

192

KAWAMURA

geant and Hoek, 197 4b) suggested that Calanus hyperboreus, Parathemisto libellula,
Thysanoessa inermis and Th. raschii are the most possible food organisms of bowheads
in the Cape Lambton and Cape Parry regions in the Beaufort Sea.
Scoresby (1820) writes the way of feeding by the bowhead whale, the largest
skimmers ever existed as follows: " When the whale feeds, it swims with considerable velocity below the surface of the sea, with its jaws widely extended. A
stream of water consequently enters its capacious mouth, and along with it, large
quantities of water insects; the water escapes again at the sides; but the whalebone,which, from its compact arrangement, and the thick internal covering of hair, does
not allow a particle the size of the smallest grain to escape ".
Right and pygmy right whales are the dwellers of the subarctic and/or subantarctic regions where the most highest marine production is usually expected.
There have been reported that these animals as microplanktonophagi feed exclusively on copepods which predominate in theirown habitat: Calanus .finmarchicus,
Thysanoessa inermis and pteropods but lesser extent in the North Atlantic waters,
but this assemblage changes to Calanus plumchrus (Matuura and Maeda, 1942), C.
cristatus, and possibly Metridia sp. in the North Pacific and Okhotsk Sea. They
may also feed Calanus paci:ficus and Euphausia pacifica in the more southen waters from
northern Japan to the boreal regions of the North Pacific (Omura, 1958). The
southern counterpart, Eubalaena glacialis australis (=E. australis) feeds both euphausiids and copepods in the subantarctic waters. Their main prey animal, however,must be Calanus tonsus, Calanus simillimus and Euphausia vallentini as it is supposed by
the occupation ofthier main feeding (=whaling) grounds during the austral summer(Townsend, 1935; Kawamura, 1978b). There also have been reported that Euphausia superba is taken in the Antarctic proper, whereas the food species change to
Grimothea larva of Munida gregaria in the waters off Patagonian coast (Matthews,
1932; 1938b).
Very little is known for the pygmy right whale. It has been reported thatthe animal as their finer baleen fringes suggest was found containing several numberof Calanus species in the South Atlantic waters (Ivashin et al., 1972).
The composition of baleen whales food in the North Atlantic waters as has been reviewed in this article seems to be somewhat monotonous assemblages when it
was compared with that found in the North Pacific and its environs. It may be un-:likely to consider these differences simply due to the faunistic characteristics in thecommunity composition of food animals, but it was the result possibly due to thelimited material sources from the less exploitation of whale stocks in the pelagic
waters using the whaling factories in the North Atlantic regions. There is no reason therefore, to believe the greater difference in the biological environments concerning the diet of baleen whales between the North Pacific and the North Atlantic oceans.
The dietary habits of great whales as well as their general biology have long
been a mythological subject but the modern whaling accompanied with a extensive biological works gradually unvailed the mystery of whales one after anotherduring the past several decades and, perhaps some more will be found but gradually
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

193

in the next.
ACKNOWLEDGMENTS

The publish of this contribution became possible sorely by the courtesy of Dr Hideo
Omura, Director of the Whales Research Institute, Tokyo, and his kind offering
the space in this volume is greatly acknowledged. Several tables and figures as indicated in the text were able to be reproduced by the courtesy of Drs P. Best, E.
Mitchell, T. Nemoto, and Fishing News Books Ltd. Without their welltimed cooperation the article was not completed in a manner intended, and all these are
greatly acknowledged. Although I tried to get reproducing permit from Dr M. M.
Sleptzov, it was unable to obtain any response, and some of his tables were usedwithout permit.
REFERENCES
ABE, T. 1957. Notes on fishes from the stomachs of whales taken in the Antarctic. I. Xenocyttus nemotoi,
a new genus and new species of zeomorph fish of the subfamily Oregosonimae Goode and Bean, 1895.
Sci. Rep. Whales Res. Inst., 12: 225-233.
BANNISTER,]. L. and A. de C. BAKER, 1967. Observations on food and feeding of baleen whales at Durban.
Norsk Hvaifangst- Tid., 56: 78-82.
BEALE, T. 1839. The Natural History of the Sperm Whale. The Holland Press, London, 393 p.
BERRY, A.]., WELLS, D.R. and C. K. No, 1973. Bryde's whale in Malaysian seas. Malay Nat. J., 26: 1925.
BERTRAM, G.C.L. 1940. The biology of the Weddell and crabeater seals, with a study of the comparative
behaviour of the pinnipedia. Brit. Mus. (Nat. Hist.) Sci. Repts. Brit. Graham Land Exped., 1934-1937, 1:
1-139.
BEST, P. B. 1960. Further information on Bryde's whale (Balaenoptera edeni Anderson) from Saldanha Bay,South Africa. Norsk Hva!fangst-Tid., 49 (5): 201-215.
BEST, P. B. 1967. Distribution and feeding habits of baleen whales off the Cape Province. Invest[ Rep.
Div. Sea Fish. S. Aji-., 57: 1-44.
BEST, P. B. 1977. Two allopatric forms of Bryde's whale off South Africa. Rep. int. Whal. Commn (Special
Issue I): 10-38.
BETESIIEVA, E. I. 1954. [Data on the feeding of baleen whales in the Kurile region]. Trans. Inst. Oceanogr.
Acad. Sci. USSR, 11: 238-245. (in Russian)
BETESHEVA, E. I. 1955. [Food of whalebone whales in the Kurile Islands region]. Trans. Inst. Oceanogr.
Acad. Sci. USSR, 18: 78-85. (in Russian)
BETESHEVA, E. I. 1961. [Feeding of the common whales of the Kurile region]. Proc. Confer. Ichthyol. Com.
Acad. Sci. USSR, 12: 104-111. (in Russian)
BRODIE, P. F., D. D. SAMEOTO and R. W. SHELDON, 1978. Population densities of euphausiids off Nova
Scotia as indicated by net samples, whale stomach contents, and sonar. Limnol; Oceanogr., 23 (6):1264-1267.
BROWN, S. G. 1968. Feeding ofsei whales at South Georgia. Norsk Hvalfangst-Tid., 57 (6): 118-125.
BuDYLENKo, G. A. 1978. On sei whale feeding in the Southern Ocean. Rep. int. Whal. Commn. 28: 379385.
CHITTLEBOROUGH, R. G. 1959. Balaenoptera Brydei Olsen on the West Coast of Australia. Norsk Hvalfangst-Tid., 4-8 (2): 62-66.
CHRISTENSEN, I. 1975. Preliminary report on the Norwegian fishery for small whales: Expansion of Norwegian whaling to Arctic and Northwest Atlantic waters, and Norwegian investigations of the biology
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

194

KAWAMURA

of small whales. J. Fish. Res. Bd. Can. 32 (7): 1083-1094.
CLARKE, R. and A. AGUAYO, L. 1965. Bryde's whale in the Southeast Pacific.

Norsk Hvalfangst-Tid.,

54 (7): 141-148.
COLLETT, R. 1886. On the external characters of Rudolphi's rorqual (Balaenoptera borealis). Proc. Z,ool.
Soc. London, XVIII: 243-265.
DALL, W. and DUNSTAN, D. 1957. Euphausia superba Dana from a humpback whale, Megaptera nodosa (Bonnaterre), caught off southern Queensland. Norsk Hvalfangst-Tid., 46 (1): 6-9.
DAWBIN, W. H. 1956. The migrations of humpback whales which pass the New Zealand coast. Trans.
ray. Soc. N.Z,., 84 (1): 147-196.
Dor, T., 0HSUMI, S. and T. NEMOTO, 1967. Population assessment ~f sei whales in the Antarctic. Norsk
Hvalfangst-Tid., 56 (2): 25-41.
DoROSHENKo, N. V. 1978. [Biology of Balaenoptera acutorostrata Lacepede 1804 in southern hemisphere].
Abstract of master's thesis, 03.00.08 Zoology. Biology. Pedology Inst., Far Eastern Center, Vladivostok: 3-21.
EARLE, S. A. 1979. Feeding behavior of humpback whales. Abstracts of papers, Committee F, Section
Fiii, XIV Pacific Science Congr., Khabarovsk, USSR: 129.
GAMBELL, R. 1968. Seasonal cycles and reproductio!1 in sei whales of the southern hemisphere. Discovery
Reports, 35: 31-134.
GAMBELL, R., BEST, P. B. and D. W. RrcE, 1974. Report on the international Indian Ocean whale marking cruise, 24 November 1973-3 February 1974. IWC/SC/26/37.
GASKIN, D. E. 1976. The evolution, zoogeography and ecology of cetacea. Oceanogr. Mar. Biol. Ann. Rev.,
14: 247-346.
HERDMAN, W. A. Sir, 1971. Founders of Oceanography and Their Work. Trans!. by K. Hidaka, Tokai Univ.
Press, Tokyo, 315 p.
H1NT0N, M.A.C. 1925. Reports on papers left by the late Major G.E.H. Barrett-Hamilton relating to the whales ofSouth Georgia. The Crown Agents for the Colonies, London: 57-209.
HJORT, J. 1933. Whales and whaling. Hvalradets Skr., 7: 7-29.
HJORT, J. and J. T. RuuD, 1929. Whaling and fishing in the North Atlantic. Rapp. Proc. Verb., Conseil.
Intern. Explor. Mer, 56 (I): 1-123.
HOLLIS, E. H. 1939. Biological report of the United States Bureau of Fisheries. Food and parasites ofwhales collected during the season 1937-1938. Norsk Hvalfangst-Tid., I: 13-17.
INGEBRIGTSEN, A. 1929. Whales caught in the North Atlantic and other seas. Rapp. Explor. Mer., LVI(27): 1-26.
IvAsH1N, M. V. et al. 1972. Z,ool. Z,h., 51: 1715-1723. (Cited from Gaskin, 1976).
J ONSGARD, A. 1951. Studies on the little piked whale or minke whale (Balaenoptera acuto-rostrata Lacepede).
Report on Norwegian investigations carried out in the years 1943-1950. Norsk Hvalfangst-Tid., 40:
209-232.
]ONSGARD, A. 1966. The distribution of Balaenopteridae in the North Atlantic Ocean. In: K. S. Norris(ed.), Whales, Dolphins, and Porpoises. Univ. Ca!if. Press, Berkeley and Los Angeles, 789 p.
]ONSGARD, A. and I. CHRISTENSEN, 1968. A preliminary report on the "Harpybuen" cruise in 1968.
Norsk Hvalfangst-Tid., 57: 174-175.
jURAsz, C. M. and V. P. JuRASz, 1979. Feeding modes of the humpback whale, Megaptera novaeangliae,
in Southeast Alaska. Sci. Rep. Whales Res. Inst., 31: 69-83.
KAWAKAMI, T., HAMABE, M. and R. SAITO, 1973. A preliminary note on the ecology of the Ommastrephid
squid Nototodarus sloani sloani (Gray) in New Zealand waters-II. Bull. Takai. Reg. Fish. Res. Lab., 76:
53-69.
KAWAKAMI, T. 1976. The fishery biological study on a squid, Nototodarus sloani sloani (Gray), in the New
Zealand waters. Bull. Tokai Reg. Fish. Res. Lab., 85: 31-104.
KAWAMURA, A. 1970. Food of sei whale taken by Japanese whaling expeditions in the Antarctic season
1967/68. Sci. Rep. Whales Res. Inst., 22, 127-152.
KAWAMURA, A. 1972. [The position of marine mammals in the marine food chains]. The Heredity, 26(II): 21-31. (in Japanese)
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

195

KAWAMURA, A. 1973. Food and feeding of sei whale caught in ihe waters south of 40°N in the North Pacific,
Sci. Rep. Whales Res. Inst., 25: 219-236.
KAWAMURA, A. 1974. Food and feeding ecology in the southern sei whale. Sci. Rep. Whales Res. Inst., 26:
25-144.
KAWAMURA, A. 1975. A consideration on an available source of energy and its cost for locomotion in fin
whales with special reference to the seasonal migrations. Sci. Rep. Whales Res. Inst., 27: 61-79.
KAWAMURA, A. 1977. On the food of Bryde's whales caught in the South Pacific and Indian Oceans. Sci.
Rep. Whales Res. Inst., 29: 49-58.
KAWAMURA, A. 1978a. On the baleen filter area in the South Pacific Bryde's whales. Sci. Rep. Whales Res.
Inst., 30: 291-300.
KAWAMURA, A. 1978b. An interim consideration on a possible interspecific relation in southern baleen
whales from the viewpoint of their food habits. Rep. int. Whal. Commn 28: 411-419.
KAWAMURA, A. 1980. Food habits of the Bryde's whales taken in the South Pacific and Indian oceans.
Sci. Rep. Whales Res. Inst,. 32: 1-23.
KAWAMURA, A. and T. KIKUNO, 1980. [On the size composition of Euphausia superba that fed by the Antarctic
minke whale]. Geiken Tushin, 334: 23-34. (in Japanese).
KELLOG, R. 1929. What is known of the migrations of some of the whalebone whales. Annual Rep. Smithsonian Institution, 1928.: 467-494.
KLuMov, S. K. 1961. Plankton and the feeding of the whalebone whales (Mystacoceti). Tru4J Inst. Okeanol., 51: 142-156.
KLUMOV, S. K. 1963. Feeding and helminth fauna of whalebone whales (Mystacoceti). Tru4J Inst. Okeanol .. , 71: 94-194.
LAws, R. M. 1977. Seals and whales of the Southern Ocean. Phil. Trans. R. Soc. Lond. B. 279: 81-96.
LIPPS, J. H. and E. MITCHELL, 1976. Trophic model for the adaptive radiations and extinctions of pelagic
marine mammals. Paleobiology, 2 (2): 147-155.
LOWRY, L. F., Frost, K.J. and J.J. Burns, 1978. Food of ringed seals and bowhead whales near Point
Barrow, Alaska. Canadian Field-Naturalist, 92 (1): 67-70.
LYTHGOE, J. & G. 1971. Fishers of the sea. Blandford Press, London, 320 p.
MACKINTOSH, N. A. 1942. The southern stocks of whalebone whales. Discovery Reports, 22: 197-300,
MACKINTOSH, N. A. 1965. The Stocks of Whales. Fishing News (Books) Ltd., London, 232 p.
MACKINTOSH, N. A. and J.F.G. WHEELER, 1929. Southern blue and fin whales. Discovery Reports, 1: 257540.
MARR, J. 1962. The natural history and geography of the Antarctic krill (Euphausia superba Dana). Discovery Reports, 32: 33-464.
MATTHEWS, L. H. 1932. Lobster krill. Discovery Reports, 5: 467-484.
MATTHEWS, L. H. 1937. The humpback whale, Megaptera nodosa .. Discovery Reports, 17: 7-92.
MATTHEWS, L. H. 1938a. The sei whale, Balaenoptera borealis. Discovery Reports, 17: 183-290.
MATTHEWS, L. H. 1938b. Notes on the southern right whale, Eubalaena australis. Discovery Reports, 17:169-182.
MATUURA, Y. and K. MAEDA, 1942. [Biological investigations of whales from the northern Pacific. The
right whale]. Hogei Shiryo, 9: 44-45. (in Japanese).
MILLA1s, J. G. 1906. The Mammals of Great Britain and Ireland. Longmans, London, 384 p. (Cited from
Gaskin, 1976).
MILLAIS, J. G. 1973. From Placentia Bay to Spitzbergen: A naturalist aboard a North Atlantic whaler.
Nature Canada, 2 (4): 4-8.
MITCHELL, E. 1973. Draft report on humpback whales taken under special scientific permit by eastern
Canadian land stations, 1969-1971. Twenty-Third Report qf the Commission, IWC, London: 138-154.
MITCHELL, E. 1974. Trophic relationships and competition for food in Northwest Atlantic whales. In:
Burt, M.D.B. (ed.), Proc. Canadian Soc. Zoologists. Ann. Meet., 123-133.
MIZUE, K. 1951. Food of whales (In the adjacent waters of Japan). Sci. Rep. Whales Res. Inst., 5: 81-90.
NEMOTO, T. 1957. Food of baleen whales in the northern Pacific. Sci. Rep. Whales Res. Inst., 12: 33-89.
NEMOTO, T. 1959. Food of baleen whales with reference to whale movements. Sci. Rep. Whales-Res. Inst.,
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

196

KAWAMURA

14: 149-290.
NEMOTo, T. 1962. Food of baleen whales collected recent Japanese Antarctic whaling expeditions. Sci.
Rep. Whales Res. Inst., 16: 89-103.
NEMOTO, T. 1970. Feeding pattern of baleen whales in the ocean. In:]. H. Steele (ed.) Marine Food Chains,
Univ. Calif. Press, Berkeley and Los Angeles, 552 p.
NEMOTO, T. and A. KAWAMURA, 1977. Characteristics of food habits and distribution of baleen whales
with special reference to the abundance of North Pacific sei and Bryde's whales. Rep. int. Whal. Commn(Special Issue 1): 80-87.
NISHIMOTO, S., M. TozAWA and T. KAWAKAMI, 1952. Food of sei whales (Balaenoptera borealis) caught in
the Bonin Island waters. Sci. Rep. Whales Res. Inst., 7: 79-85.
NISHIWAKI, M. 1959. Humpback whales in Ryukyuan waters. Sci. Rep. Whales Res. Inst., 14: 49-87.
0HSUMI, S. 1979a. Population study of the Bryde's whale in the southern hemisphere under scientific permit in three seasons, 1976/77-1978/79. IWC/SC/31/Doc. London, June.
0HSUMI, S. 1979b. Feeding habits of the minke whale in the Antarctic. Rep. int. Whal. Commn., 29, S 13:
473-476.
0HSUMI, S., Y. MASAKI and A. KAWAMURA, 1970. Stock of the Antarctic minke whale. Sci. Rep. Whales
Res. Inst., 22: 75-125.
OLSEN, 0. 1913. On the external characters and biology of Bryde's whale (Balaenoptera brydei), a newrorqual from the coast of South Africa. Proc. Z,ool. Soc. London, 1073-1090.
OMURA, H. 1958. North Pacific right whale. Sci. Rep. Whales Res. Inst., 13: 1-52.
OMURA, H. 1975. Osteological study of the minke whale from the Antarctic. Sci. Rep. Whales Res. Inst., 27:
1-36.
OMURA, H. 1977. Review of the occurrence of Bryde's whale in the North Pacific. Rep. int. Whal. Commn.
(Special Issue 1): 88-91.
OMURA, H. and H. SAKIURA, 1956. Studies on the little piked whale from the coast of Japan. Sci. Rep.
Whales Res. Inst., 11: 1-37.
OMURA, H., T. lcHIHARA and T. KASuYA, 1970. Osteology of pygmy blue whale with additional information on external and other characteristics. Sci. Rep. Whales Res. Inst., 22: 1-27.
0MORI, M., A. KAWAMURA and Y. AIZAWA, 1972. Sergestes similis Hansen, its distribution and importanceas food of fin and sei whales in the North Pacific Ocean. In: A. Y. Takenouti, Anraku, M., Banse, K.,
Kawamura, T., Nishizawa, S., Parsons, T. R., Tsujita, T., (ed.), Biological Oceanography of the Northern
North Pacific Ocean. Idemitsu Shoten, Tokyo, 626 p.
0TTESTAD, P. and Ruuo, J. T., 1936. (cited from Tomilin, 1967).
PAIVA, M. P. and N. F. GRANGEIRO, 1965. Biological investigations on the whaling season 1960-1963, off
Northeastern coast of Brazil. Arg. Est. Biol. Mar. Uniu. Fed. Ceara, Fortaleza, 5 (1): 29-64·. (cited from
Budylenko, 1978).
PAIVA, M. P. and B. F. GRANGEIRO, 1970. Investigation on the whaling seasons 1964-1967, offNortheastern
coast of Brazil. Arg. Est. Biol. Mar. Univ. Fed. Ceara, Fortaleza, 10 (2): 111-126. (cited from Budylenko,
1978).
PERVUSHIN, A. S. 1968. Observations of behaviour and feeding of whalebone whales in the area of the
Crozet Islands. Okeanologia, 8 ( 1): 139-145.
PETERS, H. 1955. Uber das Vorkommen des Walkrebschens Euphausia superba Dana und seine Bedeutung
fi.ir die Ernahrung der sudlichen Bartenwale. Arch. Fischreiwissenschaft, 6: 288-304.
PETERS, N. (ed.) 1938. Der neue Deutsche Walfang. Hansa, Deutsche Nautische Zeitschrift Carl Schroedter,
Humburg, 263 p.
PoNOMAREVA, L. A. 1949. [On the food plankton of baleen whales in the Bering Sea]. Doklaqy, Acad.
Nauk, USSR, 68 (2): 401-403. (in Russian)
RICE, D. W. 1961. Sei whales with rudimentary baleen. Norsk Hvalfangst-Tid., 50 (5): 189-193.
RICE, D. W. 1977. A list of the marine mammals of the world. NOAA Tech. Rep. NMFR, SSRF-711:
1-15.
RicE, D. W. and WOLMAN, A. A. 1971. The life history and ecology of the grqy whale (Eschrichtius robustus).
Amer. Soc. Mammalogists Spee. Puhl., 3, 142 p.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

REVIEW OF FOOD OF BALAENOPTERID WHALES

197

ROBERTS, T.J. 1977. Cetacean records for Pakistan. Studies on cetaceans, Vol. VIII: 95-99.
RqiRvIK, C.J., J. J6NSSON, 0. A. MATHISEN and A. JoNsGARD, 1976. Fin whales, Balaenoptera Pkysalus (L.),
off the west coast of Iceland. Distribution, segregation by length· and exploitation. Rit Fiskideildar,
5 (5): 1-30.
RuuD, J. T. 1937. Norsk Hvaifangst-Tid., 26, 193-194. (cited from Gaskin, 1976)
SALINIKov, N. E. 1953. [Issledovaniia Kitov Antarktiki]. Investigations of whales in the Antarctic.
Trans. VNIRO, 25: 54-67. (in Russian).
SCAMMON, C. M. 1374. The Jvfarine Mammals ef the Northwestern Coast ef North America. Dover Publications,Inc., N.Y., 319 p. 1968. (Reprint). Originally published, John H. Carmany and Co., San Francisco,and G. P. Putnam's Sons, N.Y., 1874.
SCHMIDT-NIELSEN, K. 1972. Locomotion: Energy cost of swimming, flying, and running. Science, (4045):
222-228.
SCHRAM, F. R. 1977. Paleozoogeography of late Paleozoic and Triassic malacostraca. Systematic :(ool.,
26 (4): 367-379.
ScoRESBY, W. 1820. An Account of the Arctic Regions. Vol. 2, The W~ale Fishery. Archibald Constable andCo., Edinburgh, 1820. Reprint, Redwood Press Ltd. for David & Charles (Holdings) Ltd., Newton
Abbot Devon, 574 p. 1969.
SERGEANT, D. E. and W. HOEK, 1974a. Seasonal distribution of bowhead and white whales in the eastern
Beaufort Sea. In:]. C. Reed andJ. E. Sater (eds) The coast and shelf of the Beaufort Sea. The Arctic
Inst. N. America, Washington: 705-719.
SERGEANT D. E. and W. HoEK, 1974b. Biology of the bowhead Balaena mysticetus and white whale Delphinapterus leucas in the Beaufort Sea. Interim Rep. Beaufort Sea Project Study A4, Victoria, B.C.
1-8.
SLEPTSov, M. M. 1955. [Biology and fishing of whales in the Far Eastern Seas]. S. E. Kleinenberga (ed.)
Pishepromizdat. Moskow. Japanese transl. H. Sakiura, Gieken-Sosho, No. 1, Whales Res. Inst., Tokyo,
51 p.
SLIJPER, E.J. 1962. Whales. Hutchinson & Co., London, 475 p.
SMIRNOV, N. A., 1935. (Cited from Tomilin, 1967).
ToMILIN, A. G. 1967. Cetacea. Vol. 9, Mammals of the U.S.S.R. and aqjacent countries. Heptner, V. G. (ed.)
Israel Prag. Sci. Transl.,Jerusalem, 717 p.
TOWNSEND, C. H. 1935. The distribution of certain whales as shown by logbook records of American
whaleships. :(oologica, 19 (1): 1-50.
.
UNESCO, 1973. Check-list of the fishes of the North-eastern Atlantic and of the Mediterranean. Clofnam I. J. C.
Hureau & Th. Monad (ed.), Paris, 683 p.
UNEsco, 1973. Check-list of the fishes of the North-eastern Atlantic and of the Mediterranean. Clofnam II. J. C.
Hureau & Th. Monad (ed.), Unesco, Paris, 331 p.
WATKINS, W. A. and W. E. ScHEVILL, 1976. Right whale feeding and baleen rattle. ]our. Mamm., 57 (1):58-66.
WHEELER, A. 1969. The fishes ef the British Isles and North-West Europe. Macmillan, London, Melbourne,
Tronto, 613 p.
WILLIAMSON, G. R. 1975. Minke whales off Brazil. Sci. Rep. Whales Res. Inst., 27: 37-59.
YuKHOV, V. L. 1969. Observations on the cetacea in the Aden Gulf and the north-west part of the ArabianSea. In: Marine Mammals, Nauka, Moscow: 327-328. (cited from Budylenko, 1978).
ZENKOVICH, B. A. 1937. [The food of the Far-Eastern whales.] Doklatfy Acad. Sci. S.S.S.R., 16 (4): 231-234.
(in Russian).

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

A REVIEW OF SPERM WHALE FOOD
TAKEHIKO KAWAKAMI
Tokai Regional Fisheries Research Laboratory, Tokyo

ABSTRACTPapers on the food of sperm whales caught in various parts of the world
hitherto published were reviewed, and the outline of the informations obtained
are as follows:
The composition of the items in the sperm whale food is various according
to region, season, year, etc., depending on the composition of the food animals
inhabiting the area. The most important food items are squids, followed byfishes.
Among squids, numerically important species are histioteuthids, gonatids,
onychoteuthids and octopoteuthids. In addition to these squids, cranchiids arealso very important in some regions. Seeing their importance from the view
point of weight, the important species are octopoteuthids and histioteuthids
nearly all over the world except some regions, and onychoteuthids, architeuthids and ommastrephids are important in some regions.
Though the species of fishes in the food of sperm whales are various, they
are less important than squids. They are rather important in the northeastern part of the North Pacific, New Zealand waters and the northern part of
the North Atlantic.
The important fishes as the food of sperm whales are rock fishes, cod,sharks, rag fish, skate, dory-type fish, ling, lumpsucker, etc., though the degreeof the importance of them are different according to region.
Sperm whales sometimes attack and catch large squids, e.g. Architeuthis sp.
and Moroteuthis robusta of 2-3 m in mantle length, and also large fishes of 13 m in total length such as sharks Cetorhinus maximus, Somniosus sp. etc., Dissostichus mawsoni, etc.
The amount of the stomach contents of sperm whales has been consideredless than 300 kg, and the foods consumed in a day have been considered differently by person as 2-3 tons or 1 ton. And also there is another estimate:
300 kg and 200 kg for average-sized male and female sperm whale respectively. The total weight of squids eaten by sperm whales in a year has been
estimated to be 110-320 million tons.
INTRODUCTION

The sperm whale (Physeter macrocephalus Linnaeus) has 20-28 teeth in each side of thelower mandible, the diameters of which attain 10 cm (Nishiwaki 1965). These
teeth have the function to attract and catch cephalopods, particularly the large
squids, which are the staple food of the sperm whales. Fishes are, as Clarke, R.
(1956) said, subsidiary, but not negligible, items of food.
The foods of sperm whales in various regions have long been studied by many
Sci. Rep. Whales Res. Inst.,

No. 32, 1980, 199-218

KAWAKAMI200
TABLE I.

OCCURRENCES OF SQUIDS AND FISHES IN THE STOMACHS
Number and percent (of the stomachs

Locality

Japan
Japan

Japan
KurilesNumberstomachs
observed

Numberstomachs
with food

555
1365
1379
2744
65
360?

338
809
818
1627
65
360?

Kuriles (Okhotsk)(Pacific)
Kamchatka
Bering Sea(Komandorskiye)
67(Aleutorskiye)
29
14(Northern)
110(Total)Bering Sea and Aleutian coast-180")(( l 80"- l 60"W)
Coast of Alaskan Gulf
( l 60"- l 3G°W)
British Columbia
Central California
New Zealand
IcelandAzoresAntarctic

South Georgia andSouth Africa

Octopus

Squid
No.

%

No.

%

323*
725
788
1513
65
>250*

96
90
96
93
100
>69

10
16
3
19

3
2
0

6

11

!'3-100
4- 97
21
67
26
14
107

66 (50)21 (14)10 ( 5)
97 (69)99 (75)81 (54)71 (36)91 (64)

256
148
612
125

240
129
434
116

94
8
71
93

139

45
35
52
95

32
;;:;70
96
81

50
128
133

;;;;so

57
39

27
28?

55
100?

129

49
28
56
115

74

63

63

100

54
118

scientists. A detailed review of their results was made by Berzin in 1971. Since
then the several researches on this problem have been made, especially on squids(Clarke, M. R. 1972, 1977; Clarke, M. R. et al., 1974, 1976; Kawakami, 1976;
Okutani et al., 1976, 1978). Recently the taxonomic studies of squids by beaks
have been developed by Clarke, M. R. et al. and the studies on the food of sperm
whales have advanced with a lot of beak samples removed from the stomachs ofsperm whales caught in various parts of the world, and their results were summedup (Clarke, M. R., 1977, 1980).
I have again reviewed the published reports on the foods of sperm whales inSci. Rep. Whales Res. Inst.,

No. 32, 1980

201

SPERM WHALE FOOD, REVIEWOF SPERM WHALES TAKEN FROM DIFFERENT PARTS OF THE WORLD
Number andpercent (of thestomachs observed)
empty stomachs

with food) stomachs with
Others

Fish
No.

%

5
68
25
93

8
3
6

llO**

30

4

No.

2
2

%

No.

%

0
0

217
556
561
1117
0
O?

39
41
41
41
0
O?

25 ( I)
46 (19)64 (29)36 ( 9)
7
13
29
7

94
;;;;45
33
93

68
90?
61
79

48
4
7
6

98
14
13
5

7

11

Omura 1950
Mizue 1951

Males
Females
Total*: Only squid

Kawakami 1976
Betesheva andAkimushkin 1955** : Including
squid remainders
Tarasevich 1963

57-10013- 501917 ( I)
12 ( 5)
9 ( 4)
38 (10)
16
19
178
9

SourceRemarks

Tomilin 1957

3

10

3

3

In parentheses, foronly squids
or fishes

Berzin 1959

1960
1963
1960
1963

Okutani and
Nemoto 1964

1963
2

8
O?

14
O?

15

ll

8
ll

14
28

H

ll

Males
Both sexes
Males
Males

ll

15

Both sexes

Pike 1950
Rice 1963
Gaskin andCawthorn 1967
Roe 1969
Clarke, R. 1956
Korabelnikov
1959
Matthews 1938

various regions, and summarised them. But I could not fully refer to Dr Clarke's
latest paper (1980) as I could get it only after the completion of this manuscrpt.
RELATIVE IMPORTANCE OF SPECIES IN THE FOOD OFSPERM WHALES
The frequencies of occurrence of various food items of sperm whales are different
according to the region, ~eason, year, etc., and also it may be varied by sex, age, orbody length, but various species of cephalopods predominate almost always andSci. Rep. Whales Res. Inst.,
No. 32, 1980

202

KAWAKAMITABLE 2. RATIO OF OCCURRENCE OF SQUIDS AND FISHES IN THE STOMACHS
OF SPERM WHALES TAKEN FROM DIFFERENT PARTS OF THE WORLD

Locality
Japan
Japan

Japan
Kulile Islands
Bering Sea(Komandorskiye)(Aleutorskiye)(Northern)(Total)Bering Sea and Aleutian Coast-180")( l 80- l 60"W)

Coast of Alascan Gulf
(160-130°W)
British Columbia
Central California
New Zealand
IcelandAzoresSouth Georgia and South Africa
Notes:

Ratio of occurrencein percentage

Sex ofwhalesYearobserved

Squid

Fish

98
91
97
94
100
69

2
9
3
6
0
31

80
64
53
72

20
36
47
28

1957

94
87
71
93

6
13
29
7

1960
1963
1960
1963

32
;:;;446151
36
87;:;;
90

68
56;:;;
39
49
64

1963
1948-49
1959-62
1963-64
1967
1949
1932-35

~13

10

Males
Females
Total

1948-49
1946-48""
1772
1951-52?

Males
Both sexes
Both sexes

1) The ratios were calculated with the numbers of stomachs having squid and fish.
2) Sources are the same as those in Table l.

everywhere.
The composition of the food items in sperm whale depends on the composition of the food animals inhabiting the area where the whales take food (Berzin1971), but it does not always represent the fauna of the area. This may be thinkable from the fact that species composition of the families is different between net
samples and whales' stomach contents, and many of those taken by nets are smaller species and not young specimens of the large species sampled by whales (Clarke,
M. R., 1977).
The most important food items of sperm whales are cephalopods, followed byfishes as are shown in Tables I and 2. In addition to cephalopods and fishes,
crabs, shrimps, krill, lobsters, colonial tunicates, jelly-fishes, sponges, starfishes, sea
cucumbers, vibrissae, gorgonians, etc. were reported from the stomachs of sperm
whales (Mizue 1950, Clarke, R. 1956, Tarasevich 1963), but these are not considered to be the normal food items.
The families and species of cephalopods and fishes. reported as the food of
sperm whales by many scientists are summarised in Appendix Tables I and II.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SPERM WHALE FOOD, REVIEW

203

Cephalopods as the food of sperm whales
As are shown in Appendix Table I, the cephalopods consist of 36 genera(about 56 species) belonging to 19 families, of which only 5 genera (about 6-7 species) belonging to 4 families are octopods and vampyromorph, and the other 31
genera (about 50 species) belonging to 15 families are decapods. Thus squids areof far greater irhpotance than octopods almost everywhere. But in the littoral
waters, the significance of octopods for sperm whales is sometimes greater, especially of those which have a pelagic mode of life, e. g. Amphitretus sp. and Alloposus mollis. They are sometimes found in 50% of the total number of stomachs examined(Berzin, 1971).
Most decapods in Appendix Table I are pelagic species except Loligo sp. whichis the littoral species and was found in the stomachs of sperm whales in the northeastern part of the Atlantic (Clarke, R., 1956). This may be a very rare example.
Octopus spp. are also littoral species and were reported from the stomachs of sperm
whales caught in the littoral waters of the North Pacific (Berzin, 1971).
It is noteworthy, as Berzin (1971) stated, that some of the species inhabiting
the surface waters in some regions, e. g. Todarodes pacificus which is the widespread
and abundant species in the western part of the North Pacific and serves as foodfor the most varied pelagic animals (including baleen whales), do not form apart of the sperm whales' diet.
The data on the compositions in numerical and weight percentages of familiesof cephalopod constituents in sperm whale food are available in the waters around
Japan, Kurile Islands, California, New Zealand, Peru and Chile, Iceland, Azores,
Vigo and Madeira as are shown in Table 3.
The numerically important species of cephalopods are as follows: In theJapanese waters, Histioteuthis dojleini is the most important and Octopoteuthis sp.,Moroteuthis robusta and Ommastrephes bartrami are also important (Omura, 1950; Mizue,
1951; Berzin, 1971; Kawakami, 1976; Okutani et al., 1976, 1978). In the Kurile
Islands waters, the species belonging to Gonatidae such as Gonatopsis borealis, Gonatus
magister and Gonatus fabricii, Galiteuthis armata and Histioteuthis sp. are important(Beteshe'va and Akimushkin, 1955; Berzin, 1959, 1971; Tarasevich, 1963). In the
Okhotsk Sea, Gonatus fabricii is important (Tarasevich, 1963; Berzin, 1971 ). In the
Bering Sea and the adjacent waters, Moroteuthis robusta, the species belonging to
Gonatidae such as Gonatopsis borealis, Gonatopsis makko, Gonatus magister and Gonatusfabricii, and Galiteuthis armata are important (Berzin, 1959, 1971; Okutani and Nemoto 1964). Off British Columbia and California, Moroteuthis robusta, Gonatopsis
borealis and Gonatus fabricii are important (Pike, 1950; Rice, 1963; Berzin, 1971 ;Fiscus and Rice, 1974; Clarke, M. R., 1979). In the Tasmanian and New Zealandwaters, Moroteuthis sp. and Onychoteuthis sp. are important (Gaskin and Cawthorn,
1967; Berzin, 1971; Clarke, M. R., 1977). Off Peru and Chile, Histioteuthis sp.,
Chiroteuthis spp., Octopoteuthis sp. and Dosidicus gigas are important (Berzin, 1971;
Clarke, M. R. et al., 1976; Clarke, M. R., 1977). In the eastern North Atlantic,
Histioteuthis bonelli is the most important and followed by Taningia danae (Clarke, R.,
1955 1956 ,· Clarke, M. R., 1962, 1977 ,· Keil 1963 · Roe 1969 · Berzin 1971 ·'Sci. Rep. Whales Res. Inst.,
No. 32, 1980

'

'

'

'

'

'

204

KAWAKAMITABLE 3.

COMPARISON IN NUMERICAL AND WEIGHT PERCENTAGE BY
Kurile Ialands

Japan

California

Family(1976)(1977)

Enoploteuthidae

0.1

Octopoteuthidae

11. l

19.9

Onychoteuthidae

11.4

3.9

1.3

4.0

(Okhotsk)(Pacific)

3.4

1.5

3.2

8.4

8.8

42.9

64.5

50.2

59.5

17.9

6.8

3.1

3.8

1.0

10.9

4.4

Cycloteuthidae
Gonatidae
Psychroteuthidae
Lepidoteuthidae

0.1Architeuthidoe

0.2

Histioteuthidae

30.4

38.2

Ommastrephidae

14.5

0.5

0.1

1.3

2.1

5.0

25.2

11.2

Chiroteuthidae
Cranchiidae

3.7

5.6

27.0

26.5

8.7

Pholidoteuthidae
Unidentified squid

1.5

39.3

Vampyroteuthidae
Octopodidae

2.0

0.9

0.5

Alloposidae

1.6

Amphitretidae

1.5

Others0.7

Total
Source**

100.0

100.0

86.2*

114. 3*

100.0

100.0

(1)

(2)

(3)

(3)

(4)

(5)

Notes 1) The values in parentheses are the percentage by weight.
2) *: These values are calculated by the present author in the same way as the original author
did.

Sci. Rep. Whales Res. Inst.,.No. 32, 1980

SPERM WHALE FOOD, REVIEW205

FAMILY OF THE CEPHALOPOD CONSTITUENTS IN SPERM WHALE FOOD
New
Zealand

(-)

(-)
70.7
(89. 7)

(-)
(-)
(-)

Iceland

Peru, Chile

5.5
(2.6)
9.2
(1.9)
0.1
(0. I)

(-)
3.2
(1.4)
0.1
(0.1)

AzoresCompletecollection

Mixedsample

0.2
(0.1)
3.4
(25. 3)
0.8
(5.9)
0.6
(0.4)
0.3
(0.1)
0.1
(0.0)

0.3
6.8

39.1

3.3

1.8

(-)

(-)

(-)

13.3
(1.0)
8.0
(5.6)

50.3
(56. 3)4.1(31. 7)
16. l
(1.0)
0.8
(0.5)

(-)
(-)
(-)

(-)

8.0
(3. 7)

7.6
(l.1)
3.2
(3. 3)

(-)

2.9
(0.3)
14.3
(83.0)

1.0
(0.3)
0.5
(14.2)

(-)

(-)

(-)

(-)

(-)

(-)

12.9
0.2

(-)

0.2
(3.4)
73.9
(46.5)
0.1
(0.0)
0.1
(0.0)
1.9
(0.6)
0.1
(0.0)
15.8
(10.1)

Madeira

0.7

1.0
(-)

Vigo

0.3
60.5

59. l

(-)

(-)

5.7
(2.3)
1.4
(6.6)
67.2
(5.6)

1.3
(4.0)
I. 7
(40.6)
88.3(36.1)

(-)

(-)

0.3

3.3

(-)

(-)

5.7
(0. I)

(-)

(-)

(-)

(-)

(-)

(-)

(-)

0.7
7.0

(-)
2.6

(-)

(-)

(-)

(-)

(-)

(-)

2.8
(7. 5)

2.9
(2.1)

0.8
(1.5)

(-)

(-)

(-)

(-)

(-)

(-)

(3.4)
100.0
(100.0)
(II)

(-)

(-)

(-)

(-)

100.0
(100.0)(6)100.0(100.0)(7)100.0(100.0)
(8)

100.0

100.0

(8)

(9)

100.0
(100.0)(10)3) **: (!) Okukani et al. 1976 (2) Okutani and Satake 1978 (3) Tarasevich 1963 (4) Betesheva
and Akimushkin 1955 (5) Rice 1963 (6) Gaskin and Cawthorn 1967 (7) Clarke, M. R. et al.
1976 (8) Clarke, M. R. and MacLeod 1976 (9) Clarke, R. 1956 ( 10) Clarke, M. R. and
MacLeod 1974 (11) Clarke M. R. 1962, amended by Clarke, M. R. 1974.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

206

KAWAKAMI

Clarke, M. R. and MacLeod, 1974). In the Indian Ocean, histioteuthids are themost important (Matthews, 1938; Berzin, 1971; Clarke, M. R., 1972, 1977). In
the Antarctic, onychoteuthids and cranchiids are very important (Matthews, 1938;
Korabelnikov, 1959; Berzin, 1971; Clarke, M. R., 1977).
The data on the amount of squids as the food of sperm whales are rather
numerous (Clarke, M. R., 1962; Clarke, M. R. and MacLeod, 1974, 1976; Clarke,
M. R. et al., 1976), but most of them have not been treated quantitatively (Table 3).
According to Clarke, M. R. (1977) who reported the quantitatively important squid families estimated by the beaks removed from the stomachs of sperm
whales, octopoteuthids, including the large Taningia danae, are important in all
regions except the Antarctic and off Peru and Chile, and histioteuthids, including
several species, are important everywhere expect the Antarctic. In addition tothem, onychoteuthids, architeuthids, ommastrephids such as Dosidicus gigas, Todarodes sp., Ancistrocheirus of enoploteuthid, and pholidoteuthids are also important insome regions.

Fishes as the food of sperm whales
Though the species of fishes obtained from the stomachs of sperm whales arevarious as are shown in Appendix Table II, namely 55 genera (about 68 or more
species) belonging to 49 families, the occurrence prortion of fishes in the food is not
so large as squids, and is different by region and year like cephalopods as are shownin Table 1. The ratios of occurrence of squids to fishes in the food of sperm whales
by region are shown in Table 2. In the North Pacific the fish occurrence is between 1%and68% of the stomachs having fishes and/or squids in them (Omura, 1950;
Pike, 1950; Mizue, 1951 ; Betesheva and Akimushkin, 1955; Tomilin, 195 7; Tarasevich, 1963; Rice, 1963; Okutani and Nemoto, 1964). It is only 1-9% in the Japanese waters, 31 % in the Kurile Islands waters, 6-47% in the western part of theBering Sea and Aleutian coast west of 180°, 7-29% in the Bering Sea and Aleutian
coast between 180° and 160°W, 68% off the coast of Alaskan Gulf, not less than 56%
off British Columbia and 39% off California. In the Bering Sea and Aleutian coastwest of 180° it is, as is shown in Table 2, 6-13% according to Okutani and Nemoto(1963), but it is 20%, 36% and 47% in the waters of Komandorskiye, Aleutorskiye
and northern part of the Bering Sea respectively according to Berzin (1959). Thus
fishes as the food of the sperm whales mostly predominate in the eastern waters along the Alsakan Gulf and the east Bering Sea as was stated by Okutani and Nemoto(1964), and in the northern part of the both sides of the North Pacific.
In the New Zealand waters the sperm whales take squids and fishes in nearly
the same ratio, but about one third of them feed both fishes and squids, and theratio of fishes to squids by weight was 1: 1.69 (Gaskin and Cawthorn, 1967).
In the Iceland waters of the Atlantic, fishes occur in 98% of the sperm whale
stomachs with food, in which 54% contain both squids and fishes (Roe, 1969), andthe occurrence ratio of squids to fishes is 36: 64. In the Azores waters fishes occurin 13% or less (Clarke, R. 1956). For the sperm whales in the North Atlantic,
fishes are more important in the northern part of the Ocean.
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SPERM WHALE FOOD, REVIEWTABLE 4.

FishesLamprey
Shark
Skate
Rag fishSardineSalmon-like fish
Lanternfish
Conger eel
Saury
Dory-types
South kingfish
GroperAnarrhichus minor
Ling
Rock fish
Sable fish
Lingcod
Lumpsucker
Cod
Angler fish
Total
Source207

COMPARISON IN NUMERICAL PERCENTAGE OF THE
FISHES IN SPERM WHALE FOOD
Japan

Japan

BritishColumbia

California

New
Zealand

Iceland

25.0
54.2

6.9

6.3
3.1

4.2

l. 7
13.8

2.2
3.2
20.0
35.6
4.3
6.7

6.5
29.3
12 .1
15.5
3.1
20. 7
80.0

55.9

25.0

35.6
8.3
8.3

20.0

30.1

100.0
Omura
1950

100.0
Mizue
1951

100.0
Pike
1950

100.0
Rice
1963

100.0
GaskinandCawthorn
1967

31.3
18.8
12.5
100.0
Roe
1969

Note: The percentages were calculated with the numbers of stomachs in which the fish were found by
the present author.

In the waters of South Georgia and South Africa, the fishes occur in 11 % of
the sperm whales' stomachs with food (Matthews, 1938), and in the Antarctic, in
5-13% (Clarke, R., 1956; Korabelnikov, 1959) (Table 1).
Thus, generally speaking, the occurrence proportion of fishes is not so large
as squids, and in many cases fishes are found mixed with squids. These conditions
are various according to the region, and the regions where fishes are rather important are the northern and the northeastern parts of the North Pacific, the New Zealand waters and the northern part of the North Atlantic.
The data on the composition in numerical percentage of fish constituents insperm whale food are available in the waters of Japan, British Columbia, California, New Zealand and Iceland as are shown in Table 4. The important fishes ineach region are rock fish and cod for the Japanese waters, rock fish and rag fish for
the British Columbian waters, skate and shark for Californian waters, dory-type fish
and ling for the New Zealand waters, and lumpsucker and rock fish for the Icelandwaters.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAKAMI

208

THE FEEDING TIME OF SPERM WHALES

It may be thinkable that sperm whales actively feed during night when squids comeup to the surface, and do not move about so actively in the daytime, judging fromthe catch data of the Antarctic whaling (Matsushita 1955 ), but Okutani and N emoto(1964) and Clarke, M. R. (1980) found no evidence for special feeding time in the
North Pacific and off Durban respectively.
THE SIZE OF FOOD ANIMALS EATEN BY SPERM WHALESSquidsThough the size of cephalopods usually eaten by sperm whales does not appear so large, sperm whales are considered to attack sometimes the gigantic squids.
This is considerable from the large scars up to 20 cm in diameter on the skin of
sperm whales caused by large suckers of squids, and also from the reports of huge
fragments of squids vomitted by dying whales or recovered among the stomach
contents, although Roe (1969), who recorded the sucker scars of 1.7-11.5 cm in diameter, doubted whether the very large scars such as 11.5 cm in diameter had been,
in fact, caused by squids, and considered it was possible that they were old sucker
scars which had stretched as the whale had grown (Matthews, 1938; Roe, 1969;
Berzin, 1971).
TABLE 5. SIZES OF SQUIDS FROM STOMACHS OF SPERM WHALESEXAMINED AT HORTA IN 1949 (Quoted from Clarke, R., 1956)
Sizes of squids
Length group
Small
MediumMedium-large
Large
Total
Average size of squids

Standard
length
0.6 to 0.9 m
0.9 to 1.5
1.5 to 1.8
1.8 to 2.4

Female whales

Male whales

No. of suids

No. of squids

%

41
26
2
1
70
0.95m

59
37
3

28
13
0

100

42
0.92m

%
67
31
0
2
100

Kondakov (1940) considered that the suckers as large as 20 cm in diameter
might belong to Architeuthis of 18 m in total length. The large Architeuthis whose total
length and weight were 10.5 m (mantle length was 2 m), 184 kg, and 12 m, 200 kg
were actually removed from the stomachs of sperm whales from the Azores in 1955
and from the Antarctic in 1964 respectively (Clarke, M. R., 1955; Berzin, 1971).
An architeuthid 2.4 m in mantle length was obtained from the stomach of the
sperm whale in the Azores waters (Keil 1963). In addition to these architeuthids,
Moroteuthis robusta of 2.9 m, 2.4 m and 2.4 m long were reported from the stomachsof the sperm whales caught off Kommandorskiye Islands, off British Columbia andin the Antarctic respectively (Pike, 1950; Clarke, R., 1956; Berzin, 1971 ).
As the large scars and scratches are usually found on the head of male whales,
and females are smaller in body length than males, it is often considered that male
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SPERM WHALE FOOD, REVIEW

209

sperm whales take larger squids than females (Matthews, 1938). Clarke, M. R.
(1980) also considered that males favour larger species than females by a x2 test of
the data of the sperm whales off Durban. But there is also another opinion thatmales and females take food of the same size as shown in Table 5 (Clarke, R. 1956).
The size of the food items in the diet may be different according to the ground,and an example of the difference was shown by Clarke, R. (1956) as follows: Theaverage standard length of squids from the sperm whales caught in the Azores was
0.94 m and that of the Antarctic (Moroteuthis ingens) was 1.3 m.

FishesFishes are, as stated above, generally not so important food for sperm whales
as squids, but sometimes large fishes 1-3 m in body length have been removed fromthe stomachs of sperm whales as follows: a 3 meter shark, the species of which was
unidentified, was reported off South Africa (Chabb, 1918; fido Berzin 1971), abasking shark Cetorhinus maximus 2.5 m long, at the Azores (Clarke, R., 1956), agreen shark Somniosus sp. 2.1 m long, another shark Squalus acanthias 1.3 m long,and Alepisaurus aesculopius 1.3 m long, in the Kurile waters (Betesheva, 1961 ; fido
Berzin 1971), fishes belonging to Notothenidae up to 1.5 m long and a ray Rajagriseocandata I.Im long, near Tierra del Fuego (Semskii, 1962, fido Berzin 1971),
Dissostichus mawsoni up to 1.7 m long (as a rule 1.2-1.4 m), near the Balleny Island(Berzin, 1971 ), fan tailed ragfish lcosteus aenigmaticus 1.3 m long, off British Columbia(Pike, 1950).
THE WEIGHT OF DOOD OF SPERM WHALES

The weight offood in a stomach of sperm whales
The weight of food in a stomach of sperm whales may be different according
to the size of whales, and is generally considered to be less than 300 kg. According
to Betesheva and Akimushkin (1955) and Betesheva (1961), it did not exceed 200
kg. Other data showed that stomachs contained 201-500 squid (Gonatus fabricii)(Berzin, 1971 ), the weight of which may be calculated as 80-200 kg, supposing the
average weight of this squid is 400 g. The weight of fresh food of the sperm whalesin the Cook Strait region of New Zealand was reported to have varied from 12. 7 to
105 kg (Gaskin and Cawthorn, 1967).
On the difference of the quantity of food for male and female sperm whales,
there are two different opinions. The quantity of food of sperm whales in theJapanese waters was not different between males and females (Mizue, 1950), but
the uncomplete data from the Azores suggested (not concluded) that females werefeeding rather less heavily than males, and this might be explained as follows:
females are hampered to feed heavily by calves which cannot dive deep (Clarke,R., 1956).

The amount ef sperm whale food consumed in a day and in a year
The food of sperm whales consumed in a day was considered to be at least 2Sci. Rep. Whales Res. Inst.,
No. 32, 1980

210

KAWAKAMI

3 tons of squids for a sperm whale 13-14 m long by Sleptsov (1952), and one ton
a day by Berzin (1971).
Clarke, M. R. (1977) considered the amount of food consumed in a day by
sperm whales would be 2-4% of their body weight and calculated as 300 kg
and 200 kg for males and females respectively, supposing the average body weights
were 15 tons and 5 tons for males and females respectively. As he stated that theweight of sperm whales is between 8 and 50 tons, if the largest whale is considered,
the amount of food consumed in a day will be one ton.
The total weight of cephalopods eaten by sperm whales each year has been
estimated by Clarke, M. R. (1977) to be over 110 million tons on the basis of thedata on estimated number of whales and estimated weight of food consumed bywhales, and also as a muximum figure the amount of cephalopods eaten was estimated to be 320 million tons, accepting a value of 15 tons for the average whale
and a consumption of 3.5% of body weight per day as well as an average calorificvalue of 75% of that for mascular squids.
NUTRIENT DISPERSAL BY SPERM WHALESThis problem has scarecely been studied. Sperm whales seem to eat food actively
near the surface during night as stated above, but it may be true that they certainly eat several midwater species and also eat species in spawning condition on thebottom. Therefore, it could be considerable that sperm whales probably carry nutrient upwards by eating deepsea squid and defaecating near the surface as Clarke,
M. R. (1977) stated.
Many families of cephalopods are said to have large amount of ammonia intheir tissues and coelom, and 53-78% of the number of cephalopods consumed bysperm whales are said to be ammonical squid (Clarke, M. R., 1977), which areprobably not good for human food as they are.
ACKNOWLEDGMENTS

My sincere thanks are due to Dr H. Omura, Director of the Whales ResearchInstitute, who kindly enocouraged me to make this review. I would also like toexpress my very warm thanks to Mrs Y. Takahashi of the Whales Research Institute and Mrs M. Hara of Ocean Research Institute of Tokyo University who kindly helped me in borrowing papers reffered.
REFERENCES
Aim, T., 1978. Keys to the Japanese fishes fully illustrated in colors, Hokuryukan, Tokyo, pp. 358. (in Japanese)
BERZIN, A. A., 1959. On food of sperm whale in the Bering Sea. /zvestia TINRO, 47: 161-165. (in Russian)
BERZlN, A. A., 1971. The sperm whale (Translated into English in 1972). Israel Program for Scientific
Translation, pp. 394.
BETESHEVA, E. I. and I. I. AKIMUSHKIN, 1955. Food of the sperm whale (Physeter catodon L.) in the Kurile
Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SPERM WHALE FOOD, REVIEW

211

Islands region. Truqy Inst. Okeanol. 18: 86-94. (in Russian)
CLARKE, M. R., 1962. Stomach contents of a sperm whale caught off Madeira in 1959. Norsk HvalfangstTid., 51(5):173-191.
CLARKE, M. R., 1966. A review of the systematics and ecology of ocean squids. Adv. mar. Biol., 4: 99-300.
CLARKE, M. R., 1972. New technique for the study of sperm whale migration. Nature, 238: 405-406.
CLARKE, M. R., 1977. Beaks, nets and numbers. Sym. Zoo!. Soc. London, 38: 89-126.
CLARKE, M. R., 1980. Cephalopoda in the diet of sperm whales of the southern hemisphere and their
bearing on spearm whale biology. Discovery Rep. 37. pp. 324.
CLARKE, M. R. and N. MACLEOD, 1974. Cephalopod remains from a sperm whale caught off Vigo, Spain.
J. mal. biol. Ass. U.K., 54: 959-968.
CLARKE, M. R. and N. MACLEOD, 1976. Cephalopod remains from sperm whales caught off Iceland. J.
mar. biol. Ass. U.K., 56: 733-749.
CLARKE, M. R., N. MACLEOD and 0. PALIZA, 1976. Cephalopod remains from the stomachs of sperm
whales caught off Peru and Chile. :?,ool., Lond, 180: 477-493.
CLARKE, R., 1955. A giant squid swallowed by a sperm whale. Norsk Hvalfangst-Tid., 44 (10): 589-593.
CLARKE, R., 1956. Sperm whales of the Azores. Discovery Rep., 28: 237-298.
FAR SEAS FISHERIES RESEARCH LABORATORY, 1972. Colored illustrations of bottom.fishes collected by Japanese trawlers. Japan Deep Sea Trawlers Association, Tokyo, pp. 145. (in Japanese)
FAR SEAS FISHERIES RESEARCH LABORATORY, 1976. Colored illustrations ef bottomjishes collected by Japanese trawlers. II. Japan Deep Sea Trawlers Association, Tokyo, pp. 188. (in Japanese)
Fiscus, C. H. and D. W. RICE, 1974. Giant squids, Architeuthis sp., from stomachs of sperm whales captured
off California. Calif. Fish and Game, 60 (2): 91-93.
GAMBELL, R., 1972. Sperm whales off Durban. Discovery Rep. 35, 199-358.
GASKIN, D. E. and M. W. CAWTHORN, 1967. Diet and feeding habits of the sperm whale (Pkyseter catodon L.)
in the Cook Strait region of New Zealand. N.:?,. J. mar. Freshwat. Res. 1 (2): 159-179.
lsHIKAWA, C. and Y. WAKIYA, 1914. Note on a gigantic squid obtained from the stomach ofa sperm whale.
J. Coll. Agric. Imp. Univ. Tokyo, 4 (7): 435-443.
lwAI, E., 1956a. Descriptions on unidentified species of dibranchiate cephalopods. I. An oegopsiden squid
belonging to Genus Architeuthis. Sci. Rep. Whales Res. Inst., 11: 140-146.
IWAI, E., 1956b. Descriptions on unidentified species of dibranchiate cephalopods. II. A Cranchiidae
squid of the Genus Taonius. Sci. Rep. Whales Res. Inst., 11: 153-158.
KAWAKAMI, T., 1976. Squids found in the stomach of sperm whales in the northwestern Pacific. Sci. Rep.
Whales Res. Inst., 28: 145-151.
KEIL, A., 1963. Riesentintenfische aus dem Pottwal-Magen. Natur und Museum, 93 (8): 319-323.
KoRABELNIKOV, L. V., 1959. Diet of sperm whale in the Antarctic. Priroda, 3.59: 103-104. (in Russian)
McCANN, C., 1974. Body scarring on Cetacea-Odontosetes. Sci. Rep. Whales Res. Inst., 26: 145-155.
MATSUBARA, K., 1979. Fish, morphology and hierarchy, Ishizaki-Shoten, Tokyo, pp. 1605.
MATSUSHITA, T., 1955. Daily rhythmic activity of sperm whales in the Antarctic Ocean. Bull. Japanese
Soc. Sci. Fish., 20 (9): 770-773. (in Japanese with English abstract)
MATTHEWS, L. H., 1938. The sperm whales, Physeter catodon. Discovery Rep., 17: 93-168. 9 pls.
MrzuE, K., 1950. Food of whales in the adjacent waters of Japan. Sci. Rep. Whales Res. Inst., 5: 81-90.
NrsmwAKI, M., 1965. Whales and Pinnipeds, University of Tokyo Press, Tokyo, pp. 82.
0KUTANI, T., 1973. Guide and keys to squid in Japan. Bull. Tokai Reg. Fish. Res. Lab. 74: 83-111. (inJapanese with English abstract)
0KUTANI, T., 1975. Supplements and amendments for" Guide and keys to squid in Japan". Bull. TakaiReg. Fish. Res. Lab., 83: 41-44. (in Japanese with English abstract)
0KUTANI, T. and T. NEMOTO, 1964. Squids as the food of sperm whale in the Bering Sea and Alaskan Gulf.
Sci. Rep. Whales Res. Inst. 18: 111-121.
0KUTANI, T., Y. SATAKE, S. 0HSUMI and T. KAWAKAMI, 1976. Squids eaten by sperm whales caught off
Jo ban district, Japan, during January-February, 1976. Bull. Tokai Reg. Fish. Res. Lab., 87: 67-113.
0KUTANI, T. and Y. SATAKE, 1978. Squids in the diet of 38 sperm whales caught in the Pacific off northern
Honshu, Japan, February 1977. Bull. Tokai Reg. Fish. Res. Lab., 93: 13-27.
Sci. Pep. Whales Res. Inst.,
No. 32, 1980

212

KAWAKAMIOMURA, H., 1950. Whales in the adjacent waters of Japan. Sci. Rep. Whales Res. Inst., 4: 27-113.
PrKE, G. C., 1950. Stomach contents of whales caught off the coast of British Columbia. Prog. Rep. Pacif.
Cst. Stns, 83: 27-28.
RrcE, D. W., 1963. Progress report on biological studies of the larger cetacea in the waters off California.
Norsk Hvalfangst-Tid., 52 (7): 181-187.
RoE, H.S.J ., 1969. The food and feeding habits of sperm whales (Physeter catodon L.) taken off the west coastof Iceland. j. Cons. int. Explor. Mer., 33 (!): 93-102.
TARASEVICH, M. N., 1963. Data on feeding of sperm whales in the northern area ofKurile waters. Trudy
Inst. Okeanol Akad. nauk SSSR. 71: 195-206. (in Russian with English summary).

Sci. Rep. Whales Res. Inst.
No. 32, 1980

SPERM WHALES FOOD, REVIEW213

APPENDIX TABLE I. THE CEPHALOPODS FOUND IN THE
STOMACHS OF SPERM WHALES BY AREA*
FamilyGenus Species>

Loliginidae
Loligo forbesi
Enoploteuthidae
Ancistrocheirus lesueuri +Octopoteuthidae
Octopoteuthis longiptera +0. spp.
+Taningia danae+~Cucioteuthis unguiculata Onychoteuthidae+
Onychoteuthis banksii+
0. spp.
+Moroteuthis robusta+
M. liinbergii+
lvl. ingens
lvl. robsoni
M. knipovitchi
M. sp.
Tetronychoteuthis
dussumierii
T. sp.
Kondakovia longimana
K. sp.
Cycloteuthidae
Cycloteuthis akimushkini C. sp.
Gonatidae+
Gonatus fabricii+
G. berryi+
G. antarcticus
G. sp.
+
Ber~yteuthis magister+~ Gonatus magister+
Gonatopsis borealis+
G. makko+
G. octopedatus+
Mesonychoteuthis
hamiltoni
Psychoteuthidae
Psychoteuthis sp.
Lepidoteuthidae
Lepidoteuthis grimaldii +L. sp.
Architeuthidae
Architeuthis japonica
+

N2

>

NE 3

IndianAtlantic

Pacific
NW 1> sw•>

SE 5

>

NE 3

>

> SE5l

so>

+

+

SW 4

Antarctic
Pac

Atl

Ind Ant7l

Off S.
Afr.Bl

+

+
+

+
+

+
+

+
+

+

+

+

+
+
+

+
+

+

+

+

+

+

+

+
+
+

+
+

+

+
+

+
+

+

+

+

+

+

+

+

+

+

+

+
+

+

+
+
+

+
+

+

+

+
+
+

+
+

+
+

+

+
+
+

+
+
+
+

+
+
+
+
+
+
+

+
+
+
+

+
+

+

+

+
Continued .•.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

214

KAWAKAMIAPPENDIX TABLE I.
FamilyGenus Species

Continued.

Atlantic

Pacific

IndianNWll N 2 > NE 3 > sw•> SE 5> NE 3 >sw•> SE5)

A. physeteris=Dubioteuthis physeteris A. sp.
Histioteuthidae+
Histioteuthis dojleini+=Stigmateuthis dojleini
H. sp.
=S. sp.
=Calliteuthis sp.
H. meleagroteuthi s=Meleagroteuthis+
separata
H. bonelliana
H. bonellii
H. cookiana
Ommastrephidae
Todarodes sagittatus
T. sp.
Nototodarus sloani
Ommastrephes bartrami +=Stenoteuthis bartrami +Dosidicus gigas=Ommastrephes gigas
Symplectoteuthis sp.
Chiroteuthidae
Chiroteuthis ca{yx+C. veranyi+
C. spp.
Mastigoteuthidae
Mastigoteuthis sp.
Cranchiidae
Cranchia scabra+
Taonius pavo+
T. megalops
T. spp.
+Galiteuthis armata+
G. sp.
+
Phasmatopsis li)!moctypus P. sp.
Mesonychoteuthis
hamiltonyPholidoteuthidae
Pholidoteuthis sp.
P. ? boschmai
Vampyroteuthidae
Vampyroteuthis
injernalis

+

+
+

+

+
+

+

+
+
+
+
+

+

+

S6>

+
+

Antarctic
Pac

Atl

+

Ind Ant7 >Off S.
Afr. 8 >

+

+
+

+

+

+

+
+

+

+
+

+
+

+
+

+

+

+
+

+
+
+

+

+

+
+
+
+
+
+

+
+

+
+

+

+

+

+

+

+
+

+

+

+
+

+

+

+

+

+
+
+
+
+

+
+

+
+
+

+

+
+

+
+
Continued .••Sci. Rep. Whales Res. Inst.,
No. 32, 1980

SPERM WHALE FOOD, REVIEWAPPENDIX TABLE I.

Continued.

Atlantic

Pacific

FamilyGenus Species

Indian _ _ _Antarctic_ _ _ _ _ Off S.

NW 1> N 2> NE 3 > SW 4> SE 5> NE 3> SW 4> SE5>

Vampyroteuthis sp.
Octopodidae
Octopus vulgaris
0. gilbertianus
0. sp.
Paroctopus gilbertianus
Alloposidae
Alloposus mollis
A. sp.
Amphitretidae
Amphitretus sp.

+
+
+
+
+

+

+

+
+

215

S 6>

Pac

At!

Ind Antn Afr.B·>

+

+

+
+
+

+
+
+

+

+

Notes:* The list has been drawn up on the basis of data from the works listed in the chapter " REFERENCE." The bar in the table only shows that the shecimen was not reported by this name.
1) Northwestern part of the Ocean.
5) Southeastern part of the Ocean.
2) Northern part of the Ocean.
6) Southern part of the Ocean.
3) Northeastern part of the Ocean.
7) The part of the Ocean was not reported.
4) Southwestern part of the Ocean.
8) Off South Africa.

APPENDIX TABLE II. THE FISHES FOUND IN THE STOMACHS
OF SPERM WHALES BY AREA*
At!. Ind.

Pacific
English nameLamprey
Pacific lamprey
Brown cat shark
Basking shark
Blue shark
Shark
Spined dog fish

Green shark
Greenland shark
Black shark
Shark

FamilyGenus Species
Petromyzonidae
Entophenus tridentatus
Scyliorhinidae
Apristurus brunneus
Cetorhinidae
Cetorhinus maximus
C. sp.
Carchariidae
Carcharias glaucus
Squalidae
Squalus acanthias=Koinga kirki
Dalatiidae
Somniosus sp.
S. microcephalus
Dalatias licha
D. sp.
Echinorhinidae
Echinorhinus cooki
E. sp.

z ~ z ~rn
+ +
+

~

~

~

rn

'p..°u"' ~zAntarctic
u

U:i

Ol

p..

~

"O
i::

...
i::

<i:

+
+

+
+ +

+
+
+

+

+

+
+

+
+

+
+
Continued ...

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAKAMI

216

Continued.

APPENDIX TABLE II.

English nameShark, Pacificeangel shark§: " &iz z zRound-herring

SardineSalmonSalmon like fish
Lantern fish

Large eel
Conger eel
Eel
Saury
Dory-like fish
John Dory
Porcupine fish
Mackrel3:rn ~rn 0..."" ~z~Rajidae

Myctophidae
Myctophum humboldti
Tarletonbeania crenularis
Alepisauridae=Plagiodontidae
Alepisaurus aesculapius=Plagyodus aesculapius
A. spp.
Anguillidae
Anguilla sp.
Congridae
Scombresocidae
Cololabis saira
Trachichthidae
Hoplostethus sp.
ZeidaeZeus Jaber
Diodontidae
Diodon sp.
Scombridae
Scomber japonicus
S. tapeinocephalus=S. japonicus
tapeinocephalus

c;,

""

0...

~

"O

~

c

<t;

+
+

Raja smirnovi
R. rhina
R. griseocaudat,aR. sp.
Chimaeridae
Dussumieridae
Etrumeus micropus
Clupeidae
Sardinops melanosticta
Engraulidae
Engraulis japonicus
Salmonidae
Onchorhynchus gorbusha

(.)

(.)

Squatinidae+

Squatina californica
Shark
Ray, Long nose
skate

Antarctic

At!. Ind.

Pacific
FamilyGenus Species

+

+ +

+

+

+ +

+
+

+

+

+
+
+
+

+
+
+ +
+

+
+

+

+
+
+

+

+ +
+
+
+
+
+
+
Continued ...

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

217

SPERM WHALE FOOD, REVIEWAPPENDIX TABLE II.

Continued.
Atl. Ind.

Pacific
English name

FamilyGenus Species

~

z

Tuna
Yellow fin tuna
BarracudaSouthern king fish

GroperLing
Rock fish
Red fishRock fish

Sable fish, Blackcod

ThunidaeThunus albacares
Sphyraenidae
Sphyraena sp.
Acinaceidae
Rexea solandri=Jordanidia solandriHistiopteridae
Pseudopentaceros richardsoni
Serranidae
Po[vprion oxygeneios
Anarrhichadidae
Anarrhichas minor
Ophidiidae
Genypterus blacodes
Scorpaenidae
Sebastes jlammeus
S. iracundus
s. alutus
S. mentella
S. marinus
S. ruberrimus
S. rober=Sebastodes rober
S. sp.
Helicolenus papilosus
Anoplopomidae
Anoplopoma fimbriaz z 3:
~

rJJ

~

rJJ

"'utllii..

~

Antarctic
u

z

U:i

tll

ii..

~

-0

>::
......

i::

~

+
+

+

+
+
+
+
+
+ + + +
+
+
+
+

+
+ +

Hexagramrnidae
Pleurogrammus monopterigius P. sp.
+
Ophiodon elongatus
Greeling, Ling cod
CottidaeLarge gobies+
Myoxocephalus jaok+
M. verrucosus+
M. sp
Agonidae
Percis japonica
Cyclopteridae
Cyclopterus lumpus
Lurnpsucker
Aptocyclus ventricosus+
MoridaePodonema longipes+
GadidaeCod (fish)+
Gadus macrocephalus
+

+
+

+
+

+
+

+

+
+
+
+
+

+

+
+

Continued ...

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

KAWAKAMI218

APPENDIX TABLE II.

Continued.
Pacific

English name

FamilyGenus Species;::z=G. morhua macrocephalus +G. morhua
G. aeglefinus=Melanogrammus
aeglefinus
Pollachius t•irens
Theragra chalcogramma
Walleye pollack+
Eleginus gracilis+
E. gracilis navaga+
Southern poutassou Gadidae
Micromesistius australis
Notothenidae
Dissostichus eleginoides
D. mawsoni
Coryphaenoididae
Macrurid=Macruridae
Coryphaenoides pectoralis+=Laemonema longipes
C. sp.
=Macrurns sp.
Hemimacrurus acrolepis+
Icosteidae
Icosteus aenigmaticus
Fan-tailed rag-fish
Acrotus willoughbyi
Brown ragfish
Angler fish
Lophiidae
Lophius piscatorius
Large (bathy
Ceratiidae
pelagic)
Ceratias holboelli
angler fish
Himantolophidae
Himantolophus groenlandicus
Oneirodidae
Angler fish
Oneirodes sp.
+
Pacific cod

At!. Ind.

Antarctic

~

z z
+

+
+
+
+

+

+

+

+

+
+
+
+
+

+
+

+

+ +

+

Notes:* The list has been drawn up on the basis of data from the works listed in the chapter " REFERENCE." The bar in the table only shows that the specimen was not reported by this name.
1) Northeastern part of the Ocean.
5) Southeastern part of the Ocean.
2) Northern part of the Ocean.
6) The part of the Ocean was not reported.
3) Northeastern part of the Ocean.
7) Southern part of the Ocean.
4) Southwestern part of the Ocean.

Sci. Rep. Whales Res. Inst.,
No. 32, 1980

THE SCIENTIFIC REPORTS OF THE WHALES RESEARCHINSTITUTE, TOKYO, JAPANNUMBER I, JUNE 1948
Akiya, S. and S. Tejima. Studies on digestive enzyme in whale. 3-7
Akiya, S., Y. Ishikawa, S. Tejima, and T. Tanzawa. Studies on tryptase from a whale (Balaenoptera borealisL.). 8-10
Akiya, S., S. Tejima, and Y. Ishikawa. Studies on the utilization of whale meat by the use of pancreatic
tryptase of whales. 11-14
Akiya, S. and F. Kobo. The test culture of some microorganisms with whale meat peptone. 15-16
Nakai, T. Chemical studies on the freshness of whale meat. I. Evaluation of freshness and changes inquantity of several kinds of nitrogen in whale meat following deterioration of freshness. 17-26
Nakai, T. Chemical studies on the freshness of whale meat. II. On comparison between whale meat andbeef on deterioration of freshness and autolysis. 27-30
Tawara, T. On the simultaneous extraction of vitamin A-D and vitamin B2 complex from the liver of afin whale (Nagasu-Kujira, Balaenoptera physalus L.). 31-37
Tawara, T. Studies on whale blood. I. On the separation of histidine from whale blood. 38-40
Nakai,.J. and T. Shida. Sinus-hairs of the sei-whale (Balaenoptera borealis). 41-47

NUMBER 2, DECEMBER 1948
Ogawa, T. and S. Arifuku. On the acoustic system in the cetacean brains. 1-20
Yamada, M. Auditory organ of the whalebone whales. (Preliminary report). 21-30
Nakai, T. Chemical studies on the freshness of whale meat. III. Effect of hydrogen-ion concentration on
decrease in freshness and titration curve of whale meat with HCl and Na 1 C0 2 • 31-34
Ishikawa, S., Y. Omote, and Y. Soma. Analytical distillation of vitamin A in the whale liver oil. 35-41
Ishikawa, S., Y. Ornate, and H. Kanno. Molecular distillation of sperm whale blubber oil. 42-45
Kaneko, A. Molecular distillation of fin whale liver oil. 46-50
Akiya, S. and K. Takahashi. Determination oftryptophane in whale meat. 51-54
Ishikawa, Y. and S. Tejima. Protein digestive power of sperm whale pancreatic enzyme. 55-60
Tsukamoto, S. Experiment on digestion of whale meat by koji-mould. 61-66

NUMBER 3, FEBRUARY 1950
Ogawa, T. and T. Shida. On the sensory tubercles oflips and of oral cavity in the sei and the fin whale.
1-16
Ohe, T. Distribution of the red marrow in bones of the fin whale. 17--22
Hosokawa, H. On the cetacean larynx, with special remarks on the laryngeal sack of the sei whale andthe aryteno-epiglottideal tube of the sperm whale. 23-62
Akiba, T., T. Tsuchiya, M. Umehara, and Y. Natsume. Bacteriological studies on freshness of whale
meat. (Report No. 1). 63-70
Ishikawa, Y. Protein digestive power of sperm whale pancreatic enzyme. II. 71-78
Mori, T. and M. Saiki. Properties of fats and oils contained in various parts of a sperm whale body. 7984
Tawara, T. and R. Fukazawa. Studies on kitol. I. Preparation ofkitol from whale liver oil. 85-88
Tawara, T. and R. Fukazawa. Studies on kitol. II. Influence of kitol fraction on the determination of
the International Unit of Vitamin A. 89-91
Tawawa, T. and R. Fukazawa. Studies on kitol. III. The effect of sunlight, air and heat on the vitamin
A and kitol fractions. 92-95

ii
Tawara, T. On the respiratory pigments of whale (Studies on whale blood II.). 96-101
Yoshida, M. Research on methionine in whale. 102-105
Mizue, K. Factory ship whaling around Bonin Islands in 1948. 106-118
Mizue, K. and H. Jimbo. Statistic study of foetuses of whales. 119-131
Nishiwaki, M. and K. Hayashi. Biological survey of fin and blue whales taken in the Antarctic season
1947-48 by the Japanese fleet. 132-190

NUMBER 4, AUGUST 1950
Omura, H. On the body weight of sperm and sei whales located in the adjacent waters of Japan. 1-13
Omura, H. Diatom infection on blue and fin whales in the Antarctic whaling area V (the Ross Sea area).
14-26
Omura, H. Whales in the adjacent waters ofJapan. 27-113
Nishiwaki, M. Determination of the age of Antarctic blue and fin whales by the colour changes in crystalline lens. 115-161
Nishiwaki, M. Age characteristics in baleen plates. 162-183
Nishiwaki, M. On the body weight of whales. 184-209

NUMBER 5, JUNE 1951
Akiba, T., M. Umehara and Y. Natsume. Bacteriological studies on freshness of whale meat. (Report
No. II.). 1--4
Hosokawa, H. On the pelvic cartilages of the Balaenoptera-foetuses, with remarks on the specifical andsexual difference. 5-15
Ohe, T. Iconography on the abdominal cavity and viscera of the Balaenoptera, with special remarks upon
the peritoneal coverings. 17-39
Akiya, S. and 0. Hoshino. Isolation of histidine from whale blood using 3,4-dichlorobenzene sulfonic acid.
41-47
Tawara, T. and R. Fukazawa. Studies on kitol. IV. Purification of kitol by chromatographic. 49-51
Ishikawa, S., Y. Omote and H. Okuda. Substances related to vitamin A in the whale liver oil. 53-59
Ishikawa, S., Y. Omote, M. Kijima and H. Okuda. Thermal decomposition ofkitol. 61-69
Mizue, K. Grey whales in the east sea area of Korea. 71-79
Mizue, K. Food of whales (In the adjacent waters of Japan). 81-90
Nishiwaki, M. and T. Ohe. Biological investigation on blue whales (Balaenoptera musculus) and fin whales( Balaenoptera physa/us) caught by the Japanese Antarctic whaling fleets. 91-167

NUMBER 6, DECEMBER 1951
Hosokawa, H. On the extrinsic eye muscles of the whale. with special remarks upon the innervation andfunction of the musculus retractor bulbi. 1-33
Murata, T. Histological studies on the respiratory portions of the lungs of cetacea. 35-47
Kojima, T. On the brain of the sperm whale (Physeter catodon L.). 49-72
Mizue, K. and T. Murata. Biological investigation on the whales caught by the Japanese Antarctic whaling
fleets season 1949-50. 73-131
Nishiwaki, M. On the periodic mark on the baleen plates as the sign of annual growth. 133-152
Nishiwaki, M. and T. Hibiya. On the sexual maturity of the sperm whales (Ph_yseter catodon) found :11 theadjacent waters of Japan (I). 153-165
Nakai, T. Chemical studies on freshness of whale meat. IV. Some informations of Archomobacter ubiquitum
isolated from whale carcass. 167-176
Nakai, T. and H. Ono. The effects of electric shock and fatigue on post-mortem changes in muscle. 177185

iii
Omote, Y. Complete recovery of vitamin A from molecular distillation residue of whale-liver oil. 187191
Omote, Y. Chemical structure ofkitol (I). Double bonds and hydroxyl groups. 193-198
Hirata, M. Experimental investigation on flattened head harpoon. An attempt for restraining ricochet.
199-207

NUMBER 7, JULY 1952
Ogawa, T. On the cardiac nerves of some cetacea, with special reference to those of Berardius bairdii
Stejneger. 1-22
Akiya, S., 0. Hoshino and N. Motohashi. On an attempt to preserve whale meat freshness with 5-nitrofurfuriden aminoguanidine from decay. 23-30
Akiya, S. and R. Sawamura. Colorimetric determination of 5-nitro-2-furfuridene aminoguanidine. 31-36
Tomiyama, S. and M. Takao. Studies on utilization of higher fatty alcohol from sperm whale oil. 37-46
Omote, Y. A rapid method for the separate determination of vitamin A and kitol in the whale-liver oil.
47-50
Arai, Y. and S. Sakai. Whale meat in nutrition. 51-67
Yamaguchi, K. and K. Fujino. On the serological constitution of striped dolphin (Prodelphinus caeruleoalbus(Meyen)) (I). 67-77
Nishimoto, S., M. Tozawa and T. Kawakami, Food ofsei whales (Balaenoptera borealis) caught in the Bonin
Island waters. 79-85
Nishiwaki, M. On the age-determination of Mystacoceti, chiefly blue and fin whales. 87-119
Nishiwaki, M. and T. Hibiya. On the sexual maturity of the sperm whales (Physeter catodon) found in theadjacent waters of Japan (II). 121-124
Ohno, M. and K. Fujino. Biological investigation on the whales caught by the Japanese Antarctic whaling
fleets, season 1950/51. 125-183

NUMBER 8, JUNE 1953
Yamada, M. Contribution to the anatomy of the organ of hearing of whales. 1-79
Omura, H. Biological study on humpback whales in the Antarctic whaling areas IV and V. 81-102
Fujino, K. On the serological constitutions of the sei-, fin-, blue- and humpback-whales (I). 103-125
Ogawa, T. On the presence and disappearance of the hind limb in the cetacean embryos. 127-132
Nishiwaki, M. and T. Yagi. On the age and the growth of teeth in a dolphin (Prodelphinuscaeruleo-albus).
(I). 133-146
Kakuwa, Z., T. Kawakami and K. Iguchi. Biological investigation on the whales caught by the Japanese Antarctic whaling fleets in the 1951-52 season. 147-213
Nishiwaki, M. Hermaphroditism in a dolphin (Prodelphinus caeruleo-albus ). 215-218

NUMBER 9, JUNE 1954
Akiya, S., 0. Hoshino and N. Motohashi. Attempt to preserve freshness of whale meat with germicides.
II. 1-10
Ogawa, T. On the musculature of the sinus venosus and its continuation with the so-called conducting
system of the whale's heart. 11-35
Yamada, M. Some remarks on the pygmy sperm whale, Kogia. 37-58
Yamada, M. An account ofa rare porpoise, Feresa Gray from Japan. 59-88
Omura, H. and K. Fujino. Sei whales in the adjacent waters ofJapan. II. Further studies on the external
characters. 89-103
Fujino, K. On the serological constitution of the sperm- and Baird beaked-whales (I) Blood groups ofthe sperm- and Baird beaked-whales. 105-120

iv
Fujino, K. On the body proportions of the fin whales (Balaenoptera physalus (L)) caught in the northern
Pacific Ocean (I) (Preliminary report). 121-163
Nishiwaki, M., T. Hibiya and S. Kimura. On the sexual maturity of the sei whale of the Bonin waters.
165-177
Uda, M. Studies of the relation between the whaling grounds and the hydrographical conditions (I).
179-187

NUMBER 10, JUNE 1955
Hosokawa, H. Cross-sections ofa 12-mm. dolphin embryo. 1-68
Nemoto, T. White scars on whales (I) Lamprey marks. 67-77
Omura, H. and T. Nemoto. Sei whales in the adjacent waters of Japan. III. Relation between movement and water temperature of the sea. 79-87
Omura, H., K. Fujino and S. Kimura. Beaked whale Berardius bairdi of Japan, with notes of -?,iphiuscavirostris. 89-132
Fujino, K. On the body weight of the sei whales located in the adjacent waters ofJapan (II.) 133-141
Nishiwaki, M. On the sexual maturity of the Antarctic male sperm whale (Physeter catodon L.). 143-149
Ohta, K., T. Watarai, T. Oishi, Y. Ueshiba, S. Hirose, T. Yoshizawa, Y. Akikusa, M. Sato and K. Okano,Composition of fin whale milk. 151-167

NUMBER 11, JUNE 1956
Omura, H. and H. Sakiura. Studies on the little piked whale from the coast of Japan. 1-37
Nishiwaki, M., T. Hibiya and S. Kimura. On the sexual maturity of the sperm whale (Physeter catodon)
found in the North Pacific. 39-46
Fujino, K. On the body proportions of the sperm whales (Pr,yseter catodon). 47-83
Fujino, K. On the serological constitution of the fin whales II. Further studies on blood groups. 85-98
Nemoto, T. On the diatoms of the skin film of whales in the northern Pacific. 99-132
Hoshina, T. and Y. Sugiura. On a skin disease and a nematode parasite of a dolphin, Tursiops truncatus(Montagu, 1821). 133-138
Iwai, E. Descriptions on unidentified species of dibranchiate cephalopods. I. An oegopsiden squid belonging to the genus Architeuthis. 139-151
Iwai, E. Descriptions on unidentified species of dibranchiate cephalopods. II. A cranchiidae squid of thegenus Taonius. 153-161
Uda, M. and K. Nasu. Studies of the whaling grounds in the northern sea-region of the Pacific Ocean inrelation to the meteorological and oceanographic conditions. (Part I). 163-179
Kimura, S. and T. Nemoto. Note on a minke whale kept alive in aquarium. 181-189
Ishikawa, Y. A characteristic property of whale oils concerning the absorption of gases. I. On the absorption of carbon dioxide by whale oils. 191-213

NUMBER 12, JUNE 1957
Omura, H. Osteological study of the little piked whale from the coast of Japan. 1-21
Nishiwaki, M. Age characteristics of ear plugs of whales. 23-32
Nemoto, T. Foods of baleen whales in the northern Pacific. 33~9
Nasu, K. Oceanographic conditions of the whaling grounds in the waters adjacent to Aleutian Islands andthe Bering Sea in summer of 1955. 91-101
Kimura, S. The twinning in southern fin whales. 103-125
Ichihara, T. An application of linear discriminant function to external measurements of fin whale. 127189

v
Nishiwaki, M. Very small embryo of cetacea. 191-192
Nishiwaki, M. One-eyed monster of fin whale. 193-195
Ogawa, T. and T. Kamiya. A case of the cachalot with protruded rudimentary hind limbs. 197-208
Uda, M. and A. Dairokuno. Studies of the relation between the whaling grounds and the hydrographic
conditions. II. A study of the relation between the whaling grounds off Kinkazan and the boundaryof water masses. 209-224
Abe, T. Notes on fishes from the stomachs of whales taken in the Antarctic. I. Xenocyttus nemotoi, a new
genus and new species of zeomorph fish of the subfamily Oreosonimae Goode and Bean, 1895. 225-233
Tsuyuki, H. On the oils contained in various blubbers of northern elephant seal, Mirounga angustirostris.
235-240NUMBER 13, SEPTEMBER 1958
Omura, H. North Pacific right whale. 1-52
Nishiwaki, M. and T. Kamiya. A beaked whale Mesoplodon stranded at Oiso Beach, Japan. 53-83
Nishiwaki, M. and C. Randa, Killer whales caught in the coastal waters off Japan for recent 10 years.
85-96
Ohsumi, S. (Kimura), M. Nishiwaki and T. Hibiya. Growth of fin whale in the northern Pacific. 97133
Nishiwaki, M., T. Hibiya and S. Ohsumi (Kimura). Age study of sperm whale based on reading of
tooth laminations. 135-153
Nishiwaki, M., T. Ichihara and S. Ohsumi (Kimura). Age studies of fin whale based on ear plug. 155169
Fujino, K. On the serological constitution of fin whale. III. Human B blood group substances in erythrocytes and some notes on anti-fin Ju specific antibodies. 171-184
Nemoto, T. Cocconeis diatoms infected on whales in the Antarctic. 185-191
Nemoto, T. and K. Nasu. Thysanoessa macrura as a food of baleen whales in the Antarctic. 193-199
Ichihara, T. Gray whale observed in the Bering Sea. 201-205
Ohsumi, S. (Kimura). A descendant of Moby Dick or a white sperm whale. 207-209
Nasu, K.. Deformed lower jaw of sperm whale. 211-212
Omura, H. Note on embryo of Baird's beaked whale. 213-214
Uda, M. and N. Suzuki. Studies of the relation between the whaling grounds and the hydrographic conditions. III. The averaged conditions of the whaling grounds and their trends of variation during
1946-55. 215-229
Seki, Y. Observations on the spinal cord of the right whale. 231-251
Kamiya, T. How to count the renculi of the cetacean kidneys, with special regard to the kidney of theright whale. 253-267
Hosokawa, H. and T. Sekino. Comparison of the size of cells and some histological formations between
whales and man. 269-301
Ogawa, T., T. Tsunoda and M. Osawa. Amino acid composition of whale meat. 303-307
Ishikawa, Y. A characteristic property of whale oils concerning the absorption of gases. II. On the absorption of nitrogen by whale oils. 309-321
Tsuyuki, H. Component fatty acids of northern elephant seal oil. 323-332

NUMBER 14, SEPTEMBER 1959
Omura, H. Bryde's whale from the coast of Japan. 1-33
Nishiwaki, M. and T. Kamiya. Mesoplodon stejenegeri from the coast of Japan. 35-48
Nishiwaki, M. Humpback whales in Ryukyuan waters. 49-87
Cushing, John E., K. Fujino and K. Takahashi. Glycerol-freezing technique as an aid in blood typingof whales. 89-100

vi
Fujino, K. and John E. Cushing. Blood typing of dried whale erythrocytes with 1311 labelled antibody.
101-106
Ichihara, T. Formation mechanism of ear plug in baleen whales in relation to glove-finger. 107-135
Nasu, K. Surface water condition in the Antarctic whaling Pacific area in 1956-57. 137-143
Ohsumi, S. (Kimura). A deformed fin whale foetus. 145-147
Nemoto, T. Food of baleen whales with reference to whale movements. 149-290
Yamada, M. and F. Yoshizaki. Osseous labyrinth of cetacea. 291-304
Nakai, T. Distribution of amino acid in proteins from various parts of whale body. 305-326

NUMBER 15, NOVEMBER 1960
Nishiwaki, M. Ryukyuan humpback whaling in 1960. 1-16
Ohsumi, S. Relative growth of the fin whale, Balaenoptera ph_vsalus (Linn.). 17-84
Fujino, K. Immunogenetic and marking approaches to identifying subpopulations of the North Pacificwhales. 85-142
Nasu, K. Oceanographic investigation in the Chukchi Sea during the summer of 1958. 143-158
Tokita, K. and ECG Research Group. Electrocardiographical studies on bottlenosed dolphin (Tursiops
truncatus). 159-165

NUMBER 16, MARCH 1962
Omura, H. Bryde's whale occurs on the coast of Brazil. 1-5
Omura, H. Further information on Bryde's whale from the coast of Japan. 7-18
Nishiwaki, M. Ryukyuan whaling in 1961. 19-28
Nemoto, T. A secondary sexual character of fin whales. 29-34
Omura, H., M. Nishiwaki, T. Ichihara and T. Kasuya. Osteological note of a sperm whale. 35-45
Ichihara, T. Prenatal dead foetus of baleen whales. 47-60
Nishiwaki, M. Mesoplodon bowdoini stranded at Akita Beach, Sea of Japan. 61-77
Nishiwaki, M. Observation on two mandibles of Mesoplodon. 79-82
Sinclair, John. An early dolphin embryo (Stenella caeruleoalbus) in serial sections. 83-87
Nemoto, T. Food of baleen whales collected in recent Japanese Antarctic whaling expeditions. 89-103
Uda, M. Subarctic oceanography in relation to whaling and salmon fisheries. 105-119

NUMBER 17, FEBRUARY 1963
Nishiwaki, M., S. Ohsumi and T. Maeda. Change of form in the sperm whale accompanied with growth.
1-14
Ohsumi, S., T. Kasuya and M. Nishiwaki. The accumulation rate of dentinal growth layers in the maxillary tooth of the sperm whale. 15-35
Ichihara, T. Photometric method for counting laminae in ear plug of baleen whale. 37-48
Yoshikawa, T. and T. Suzuki. The lamination of the masseter of the humpback whale. 49-52
Fujino, K. Intra-uterine selection due to maternal-foetal in compatibility of blood type in the whales.
53-65
Cushing, John E., K. Fujino and N. Calaprice. The Ju blood typing system of the sperm whale and specificsoluble substances. 67-77
Nemoto, T. New records of sperm whales with protruded rudimentary hind limbs. 79-81
Nemoto, T. and K. Nasu. Stones and other aliens in the stomachs of sperm whales in the Bering Sea.
83-91
Nishiwaki, M. Taxonomical consideration on genera of Delphinidae. 93-103
Nasu, K. Oceanography and whaling ground in the subarctic region of the Pacific Ocean. 105-155

vii
Nemoto, T. ·Some aspects of the distribution of Ca/anus cristatus and C. plumchrus in the Bering and its neighbouring waters, with reference to the feeding of baleen whales. 157-170
Tsuyuki, H. and U. Naruse. Studies on the oil of black right whale in the northern Pacific Ocean. 171190
Yagi, T., M. Nishiwaki and M. Nakajima. A preliminary study on the method of time marking withleadsalt and tetracycline on the teeth of northern fur seal. 191-195

NUMBER 18, MARCH 1964
Fujino, K. Fin whale subpopulations in the Antarctic whaling areas II, III and IV. 1-27
Ichihara, T. Prenatal development of ear plug in baleen whales. 29-48
Ohsumi, S. Examination on age determination of the whale. 49-88
Nemoto, T. School of badeen whales in the feeding areas. 89-110.
Okutani, T. and Nemoto, T. Squids as the food of sperm whales in the Bering Sea and Alaskan Gulf.
111-122
Ohsumi, S. Comparison of maturity and accumulation rate of corpora albicantia between the left andright ovaries in cetacea. 123-148
Omura, H. A systematic study of the hyoid bones in the baleen whales. 149-170
Nishiwaki, 1\.-1. Revision of the article " Taxonomical consideration on genera of Delphinidae" in No. 17.
171-172
Tsuyuki, H. and U. Naruse. Studies on the lipids in brain of black right whale in the northern Pacific
Ocean. 173-180

NUMBER 19, APRIL 1965
Ohsumi, S. Reproduction of the sperm whale in the north-west Pacific. 1-35
Kasuya, T. and T. Ichihara. Some informations on minke whales from the Antarctic. 37-43
Nemoto, T. and T. Kasuya. Foods of baleen whales in the Gulf of Alaska of the North Pacific. 45-51
Nishiwaki, M., M. Nakajima and T. Kamiya. A rare species of dolphin (Stenella attenuata) from Arari,Japan. 53-64
Nishiwaki, M., T. Kasuya, T. Tobayama, T. Kamiya and M. Nakajima. Feresa attenuata captured at the
Pacific Coast of Japan in 1963. 65-·90
Nakajima, M. and M. Nishiwaki. The first occurrence of a porpoise (Electra electra) in Japan. 91-104
Hosokawa, H. and T. Kamiya. Sections of the dolP.hin's head (Stenella caeruleoalba). 105-133
Ohsumi, S. A dolphin (Stenella caeruleoalba) with protruded rudimentary hind limbs. 135-136

NUMBER 20, SEPTEMBER 1966
Ohsumi, S. Sexual segregation of the sperm whale in the North Pacific. 1-16
lchihara, T. Criterion for determining age of fin whale with reference to ear plug and baleen plate. 1782
Kasuya, T. Caryotype of a sei whale. 83-88
Kasuya, T. and S. Ohsumi. A secondary sexual character of the sperm whale. 89-94
Nishiwaki, M. and K. S. Norris. A new genus, Peponocephala, for the odontoceti cetacean species Electra
eleclra. 95-100
Nishiwaki, M., M. Nakajima and T. Tobayama. Preliminary experiments for dolphin marking. 101107
Nemoto, T. Thysanoessa euphausiids, comparative morphology, allomorphosis and ecology. 109-155
Nasu, K. Fishery oceanographic study on the baleen whaling grounds. 157-210
Ichihara, T. and M. Nishiwaki. External measurements and weight of a southern elephant seal. 211-212

viii
Tsuyuki, H. and S. Itoh.

Studies on the oils contained in blubber of a southern elephant seal.

213-221

NUMBER 21, JUNE 1969
Omura, H., S. Ohsumi, T. Nemoto, K. Nasu and T. Kasuya. Black right whales in the North Pacific.
1-78
Nishiwaki, M. and Y. Hasegawa. The discovery of the right whale skull in the Kisagata shell bed. 79-84
Ohsumi, S. Occurrence and rupture of varginal band in the fin, sei, and blue whales. 85-94
Hosokawa, H., S. Igarashi, T. Kamiya and K. Hirosawa. Morphological characteristics and myelinization of acoustic system in the dolphins (Stenella caeruleoalba). 95.:..123
Mo!, T. and P.J.H. van Bree. A short contribution to the history of whaling in Japan during the I 7th
century. 125-129
Tsuyuki, H. and S. Itoh. Fatty acid composition offinless porpoise oil. 131-135.
Tsuyuki, H. and S. Itoh. Fatty acid composition of many toothed pilot whale oil. 137-141

NUMBER 22, JUNE 1970
Omura, H., T. Ichihara and T. Kasuya. Osteology of pygmy blue whale with additional info~mation on
external and other characteristics. 1-27
Nishiwaki, M. and T. Kasuya. Recent record of gray whale in the adjacent waters of Japan and a consideration on its migration. 29-37
Kasuya, T. and D. W. Rice. Note on baleen plates and on arrangement of parasitic barnacles of graywhale. 39-43
Nishiwaki, M. and T. Kasuya. A Greenland right whale caught at Osaka Bay. 45-62
Nasu, K. and Y. Masaki. Some biological parameters for stock assessment of the Antarctic sei whale.
63-74
Ohsumi, S., Y. Masaki and A. Kawamura, Stock of the Antarctic minke whale. 75-125
Kawamura, A. Food ofsei whale taken by Japanese whaling expeditions in the Antarctic season 1967/68.
127-152
Nemoto, T. and K. I. Yoo. An amphipod, Parathemisto gaudichaudii as a food of the Antarctic sei whale.
153-158
Tobayama, T., S. Uchida and M. Nishiwaki. Twin foetuses from a blue white dolphin. 159-162
Machida, S. A sword-fish sword found from a North Pacific sei whale. 163-164
Tsuyuki, H. and S. Itoh. Fatty acid components of black right whale oil by gas chromatography. 165-170

NUMBER 23, SEPTEMBER 1971
Ohsumi, S. Some investigations on the school structure of sperm whale. 1-25
Kawamura, A. Influence of chasing time to stomach contents of baleen and sperm whales. 27-36
Kasuya, T. Consideration of distribution and migration of toothed whales off the Pacific coast of Japan
based upon aerial sighting record. 37-60
Omura, H. A comparison of the size of vertebrae among some species of the baleen whales with specialreference to whale movements. 61-69
Omura, H., M. Nishiwaki and T. Kasuya. Further studies on two skeletons of the black right whale in
the North Pacific. 71-81
Nishiwaki, M. and T. Kasuya. Osteological note of an Antarctic sei whale. 83-89
Hosokawa, H. and T. Kamiya. Some observations on the cetacean stomachs, with special considerations
on the feeding habits of whales. 91-101
Lugassy, A. A., E. Korostoff and J. L. Rabinowits. Influence of incremental lines upon the compressive
strength of sperm whale den tin. 103-110

ix
Nishiwaki, M. and N. Oguro. Baird's beaked whales caught on the coast of Japan in recent JO years.
111-122
Mizue, K., M. Nishiwaki and A. Takemura. The underwater sound of Ganges river dolphins (Platanista
gangetica). 123-128
Kasuya, T. and M. Nishiwaki. First record of Mesoplodon densirostris from Formosa. 129-137
Kawamura, A. and K. Kashita. A rare double monster of dolphin, Stene/la caeruleoalba. 139-140
Tsuyuki, H. and S. Itoh. Fatty acid components of Ganges river dolphin oil. 141-147

NUMBER 24, NOVEMBER 1972
Omura, H. An osteological study of the Cuvier's beaked whale, Ziphius cavirostris, in the north west Pacific.
1-34
Nishiwaki, M. and N. Oguro. Catch of the Cuvier's beaked whales off Japan in recent years. 35--41
Nishiwaki, M., T. Kasuya, K. Kureha and N. Oguro. Further comments of Mesoplodor. gingkodens. 43-56
Kasuya, T. Growth and reproduction of Stene/la caeruleoalba based on the age determination by means ofdentinal growth layers. 57-79
Kasuya, T. and N. Oguro. A new tagging method of dolphins. 81-85
Kasuya, T. Some informations on the growth of the Ganges dolphin with a comment on the Indus dolphin.
87-108Kasuya, T. and A.K.M. Aminul Haque. Some informations on the distribution and seasonal movementof the Ganges dolphin. 109-115
Tsuyuki, H. and S. ltoh. Fatty acid component of various blubber oil of Ganges River dolphin. 117-125
Naito, Y. and M. Nishiwaki. The growth of two species of the harbour seal in the adjacent waters of
Hokkaido. 127-144
Ichihara, T. and K. Yoshida. Diving depth of northern fur seals in the feeding time. 145-148

NUMBER 25, SEPTEMBER 1973
Kasuya, T. Systematic consideration of recent toothed whales based on the morphology of tympanoperiotic bone. 1-103
Omura, H. A review of pelagic whaling operations in the Antarctic based on the effort and catch data in
10° squares of latitude and longitude. 105-203
Nasu, K. Results of whale sighting by Chiyoda Maru No. 5 in the Pacific sector of the. Antarctic andTasman Sea in the 1966/67 season. 205-217
Kawamura, A. Food and feeding of sei whale caught in the waters south of 40°N in the North Pacific.
219-236
Ohsumi, S. Find of marlin spear from the Antarctic minke whales. 237-239
Seki, Y. An anatomical study on the lower extension of the dorasl vagal nucleus to the upper cervical
cord in the sperm whale. 241-249
Tobayama, T., M. Nishiwaki and H. C. Yang. Records of the Fraser's Sarawak dolphin (Lagmodelphis
hosei) in the western North Pacific. 251-263
Miyazaki, N., T. Kusaya and M. Nishiwaki. Food of Stene/la caeruleoalba. 265-275
Nishiwaki, M. Possible vestigial teats of killer whale. 277-278
Williamson, G. R. Counting and measuring baleen and ventral grooves of whales. 279-292
Tsuyuki, H. and S. Itoh. Fatty acid component of blubber oil of Amazon River dolphin. 293-299
Naito, Y. Comparison in colour pattern of two species of harbour seal in adjacent waters of Hokkaido.
301-310x

NUMBER 26, NOVEMBER 1974
Omura, H. PoJsible migration route of the gray whale on the coast of Japan. 1-14
Satake, Y. and H. Omura. A txonomic study of the minke whale in the Antarctic by means ofhyoid bone.
15-24
Kawamura, A. Food and feeding ecology in the southern sei whale. 25-144
McCann, C. Body scarring on cetacea-odontocetes. 145-155
Kasuya, T., N. Miyazaki and W. H. Dawbin. Growth and reproduction of Stene/la attenuata in the Pacificcoast of Japan. 157-226
Miyazaki, N., T. Kasuya and M. Nishiwaki. Distribution and migration of two species of Stene/la in the
Pacific coast of Japan. 227-243
Kamiya, T. and P. Pirlot. Brain morphogenesis in Stenella coeruleoalba. 245-253
Castello, H.P., A. P. Torno and J. S. Panizza. First Antarctic record of a killer whale stranding. 255258
Kamiya, T. and N. Miyazaki. A malformed embryo of Stenella coeruleoalba. 259-263
Kamiya, T. and F. Yamasaki. Organ weights of Pontoporia blainvillei and Platanista gangetica (Platanistidae).
265-270
Machida, S. Surface temperature field in the Crozet and Kerguelen whaling grounds. 271-287
Machida, S. The voyage of the Konan Maru No. 16 to the Antarctic whaling grounds. 289-302
Itoh, S. and H. Tsuyuki. Fatty acid component of different blubber oil of finless porpoise. 303-306
Itoh, S. and H. Tsuyuki. Fatty acid component of Senegal manatee fats. 309-311
Naito, Y. Thr hyoid bones of two kinds of harbour seals in the adjacent waters of Hokkaido. 313-320

NUMBER 27, SEPTEMBER 1975
Omura, H. Osteological study of the minke whale from the Antarctic. 1-36
Williamson, G. R. Minke whales off Brazil. 37-59
Kawamura, A. A consideration on an available source of energy and its cost for locomotion in fin whales
with special reference to the seasonal migrations. 61-79
Kasuya, T. and M. Nishiwaki. Recent status of the population oflndus dolphin. 81-94
Kasuya, T. Past occurrence of Globicephala melaena in the western North Pacific. 95-108
McCann, C. A study of the genus Berardius Duvernoy. 111-137
Nishiwaki, M. and K. Kureha. Strange organ in the anal region of the finless porpoise. 139-140
Machida, S. Distribution of sperm whale catches in the southern Indian Ocean. 141-159

NUMBER 28, OCTOBER 1976
Kawamura, A. and Y. Satake. Preliminary report on the geographical distribution of the Bryde's whalein the North Pacific with special reference to the structure of the filtering apparatus. 1-35
Pivorunas, A. A mathematical consideration on the function of baleen plates and their fringes. 37-55
Omura, H. and T. Kasuya. Additional information on skeleton of the minke whale from the Antarctic.
57-68
Omura, H. A skull of the minke whale dug out from Osaka. 69-72
Kasuya, T. Reconsideration of life history parameters of the spotted and striped dolphins based on cementa! layers. 73-106
McCann, C. Notes on the foetal skull of Mesoplodon stejnegeri. 107-117
Gianuca, N. M. and H.P. Castello. First record of the southern bottlenose whale, Hyperoodon planifrons
from Brazil. 119-126
Brownell, R. L. Jr., L. A. Aguayo and N. D. Torres. A Shepherd's beaked whale, Tasmacetus shepherdi, fromthe eastern South Pacific. 127-128
Brownell, R. L. Jr. and R. Praderi. Records of the delphinid genus Stenella in western South Atlantic

xiwaters. 129-135
Yamasaki, F., H. Satomi and T. Kamiya. An observation on the papillary projections at the lingual
margin in the striped dolphin. 137-140
Kasuya, T. and N. Miyazaki. An observation of epimeletic behavior of Lagenorhyncus obliquidens. 141143
Kawakami, T. Squids found in the stomach of sperm whales in the northwestern Pacific. 145-151
Leung, Y. M. Life cycle of <:;nmus scammoni (Amphipoda: Cyamidae), ectoparasite of gray whale, witha remark on the associated species. 153-160
Kagei, N., T. Tobayama and Y. Nagasaki. On the helminthum of Franciscana, Pontoporia blainvillei.
161-166
Tsuyuki, H. and S. Itoh. Fatty acid component oflipid of Euphausia superba. 167-174
Naito, Y. The occurrence of the phocid seals along the coast ofJapan and possible dispersal of pups. 175185
Naito, Y. and M. Oshima. The variation in the development of pelage of the ribbon seal with reference
to the systematics. 187-197

NUMBER 29, DECEMBER 1977
Kasuya, T. Age determination and growth of the Baird's beaked whale with a comment on the feta!
growth rate. 1-20
Miyazaki, N. On the growth and reproduction of Stene/la coeruleoalba off the Pacific coast ofJapan. 21-48
Kawamura, A. On the food of Bryde's whales caught in the South Pacific and Indian Oceans. 49-58
Herman, L. M. and R. C. Antinoja. Humpback whales in the Hawaiian breeding waters: population andpod characteristics. 59-85
Aminul Haque, A.K.M., M. Nishiwaki, T. Kasuya and T. Tobayama. Observations on the behaviourand other biological aspects of the Ganges susu, Platanista gangetica. 87-94
Yamasaki, F., S. Komatsu and T. Kamiya. A comparative morphology of anal tonsils in Platanistidae.
95-100
Nemoto, T., R. L. Brownell, Jr. and T. Ishimaru. Coconeis diatom on the skin of Franciscana. 101-105
Castello, H.P. Food of a killer whale: Eagle sting-ray, Myliobatis found in the stomach of a stranded
Orcinus orca. 107-111
Nishiwaki, M. and A. Sasao. Human activities disturbing natural migration routes of whales. 113-120
Yoshida, K., N. Baba, M. Oya and K. Mizue. On the formation and regression of corpus luteum in thenorther.n fur seal ovaries. 121-128
Abe, H., Y. Hasegawa and K. Wada. A note on the air-sac ofribbon seal. 129-135
Kawamura, A. and T. Furuno. On the northern extremes of pack ice observed by whaling vessels in thesummer of the Antarctic seasons 1957/58-1962/63. 137-141

NUMBER 30 DECEMBER 1978
Kasuya, T. The life history of Dall's porpoise with special reference to the stock off the Pacific coast ofJapan. 1-64
Miyazaki, N. and M. Nishiwaki. School structure of the striped dolphin off the Pacific coast of Japan.
65-116
Clarke, R., A. Aguayo L. and S. B. de! Campo. Whale observation and whale marking off the coast of
Chile in 1964. 117-178
Miyazaki, N. and S. Wada. Observation of cetacea during whale marking cruise in the western tropical
Pacific, 1976. 179-196
Goodall, R. N. P. Report on the small cetaceans stranded on the coasts of Tierra de! Fuego. 197-232
Miyazaki, N. and S. Wada. Fraser's dolphin, Lagenodelphis hosei in the western North Pacific. 231-244
Nemoto, T. Humpback whales observed within the continental shelf waters of the eastern Bering Sea.

xii

245-247
Yamamoto, Y. and H. Hiruta. Stranding of a black right whale at Kumomi, southwestern coast of Izu
Peninsula. 249-251
Klima, M. Comparison of early development of sternum and clavicle in striped dolphin and in humpback
whale. 253-269
Omura, H. Preliminary report on morphological study of pelvic bones of the minke whale from theAntarctic. 271-279
Kamiya, T., F. Yamasaki and S. Komatsu. A note on the parathyroid glands ol Ganges susu. 281-284
Yamasaki, F., S. Komatsu and T. Kamiya. Taste buds in the pits at the posterior dorsum of the tongueof Stenella coeruleoalba. 285-290
Kawamura, A. On the baleen filter area in the South Pacific Bryde's whales. 291-300
Kasuya, T. and M. Nishiwaki. On the age characteristics and anatomy of the tusk of Dugan.if dugon.
301-310
Kagei, N., K. Asano and M. Kihata.
superba. 311-313

On the examination against the parasites of Antarctic krill,

Euphausia

NUMBER 31, DECEMBER 1979
Kasuya, T. and K. Kureha. The population of finless porpoise in the Inland Sea of Japan. 1-44
Kasuya, T. and R. L. Brownell Jr. Age determination, reproduction, and growth of Frnaciscana dolphin,
Po11toporia blainvillei. 45-67
Jurasz, C. M. and V. P. Jurasz. Feeding modes of the humpback whale, Megaptera novaeangliae, insoutheast Alaska. 69-83
Omura, H. and T. Kasuya. A skull of baleen whale dredged from the Inland Sea of Japan. 85-92
Kamiya, T., T. Tobayama and M. Nishiwaki. Epidermal cyst in the neck of a killer whale. 93-94
Major, P. F. An aggressive encounter between a pod of whales and billfish. 95-96
Kato, H. Carotenoid colored minke whale from the Antarctic. 97-99
Kato, H. Unusual minke whale with deformed jaw. 101-103
Naito, Y. and S. Konno. The post breeding distributions of ice-breeding harbour seal (Phoca largha)
and ribbon seal (Phoca fasciata) in the southern sea of Okhotsk. 105-119
Naito, Y. A record of the bearded seal wandering with special reference to the wandering speed.
121-123
Miyazaki, N., K. Itano, M. Fukushima, S. Kawai and K. Honda. Metals and organochlorine compounds in the muscle of dugong from Sulawesi Island. 125-128
Kamiya, T., S. Uchida and T. Kataoka. Organ weights of Dugong dugon. 129-132
Nishiwaki, M., T. Kasuya, N. Miyazaki, T. Tobayama and T. Kataoka. Present ditribution of the dugong
in the world. 133-141

NUMBER 32, DECEMBER 1980
Kawamura, A. Food habits of the Bryde's whales taken in the South Pacific and Indian oceans. 1-23
Omura, H. Morphological study of pelvic bones of the minke whale from the Antarctic. 25-37
Hohn, A. A. Age determination and age related factors in the teeth of western North Atlantic bottlenose
dolphins. 39-66
Yonekura, M., S. Matsui and T. Kasuya. On the external characters of Globicephala macrorhy11ehus off Taiji,
Pacific coast of Japan. 67-95
Nemoto, T., P. B. Best, K. Ishimaru and H. Takano. Diatom films on whales in South African waters.
97-103Kamiya, T. and P. Pirlot. Brain organization in Platanista gangetica. 105-126
Yamasaki, F., S. Komatsu and T. Kamiya. A comparative morphological study on the tongues ofmanatee and dugong (Sirenia). 127-144

xiii
Casinos, A. and J. Bou. On a massive stranding of short-finned pilot whale, Globicephala macrorhynchus
Gray, 1846, on Margarita Island (Venezuela). 145-148
Mermoz, J. F. A brief report on the behavior of commerson's dolphin, Cephalorhynchus commersonii, in
Patagonian shores. 149-154
Kawamura, A. A review of food of balaenopterid whales. 155-198
Kawakami, T. A review of sperm whale food. 199-218

SUBJECT INDEX

Taxonomy, Body proportionand Osteology
Balaena mysticetus 22: 45-62
Euba/aena glacia/is 13: 1-52, 21: 1-78, 21: 79-84,
23: 71-81, 30: 249-251
Eschrichtius robustus 22: 29-37, 26: 1-14
Balaenoptera musculus 7: 125-183
B. musculus brevicauda 22: 1-27
B. Pkysalus 7: 125-183, 9: 121-163, 12: 127-189,
J.'i: 17-84, 16: 29-34
B. borealis 9: 89-103, 14: 1-33, 23: 83-89
B. edeni 9: 89-103, 14: 1-33, 16: 1-5, 16: 7-18,
31: 85-92
B. acutorostrata II: 1-37, 12: 1-21, 19: 37-43, 22:75-125, 27: 1-36, 28: 57-68, 28: 69-72
Megaptera novaeangliae 7: 125-183, 14: 49-87
Physeter catodon 7: 125-183, 11: 47-83, 16: 35-45,
17: 1-14
Kogia sp. 9: 37-58
Tasmacetus shepherdi 28: 127-128
Mesoplodon ginkgodens 13: 53-83, 24: 43-56
M. densirostris 23: 129-137
M. st1!)negeri 14: 35-48, 28: 107-117
M. bowdoini 16: 61-77
M. sp. 16: 79-82:(,iphius cavirostris 24: 1-34
Berardius 27: 111-137
B. bairdii 10: 89-132
Hyperoodon planifrons 28: 119-126
Peponocephala e/ectra 19: 91-104, 20: 95-100
Feressa attenuata 9: 59-88, I 9: 65-90
Orcinus orca 26: 255-258
Globicephala macrorkynchus and G. melaena 27: 95110
Globicephala macrorhynchus 32: 67-95, 32: 145-148
Lagenodelphis hosei 25: 251-263, 30: 231-244
Stene/la attenuata 19: 53-64
S. spp. 28: 129-135
Platanista gangetica 24: 87-108
Small cetaceans; Tierra de! Fuego 30: 197-230
Mirounga leonina 20: 211-212
Systematic study
Pelvic bone 5: 5-15, 30: 271-279, 32: 25-37
Hyoid bone, baleen whales 18: 149-170
Balaenoptera acutorostrata 26: 15-24
Phoca 26: 313-320
Sternum and clevicle
Stene/la coeru/eoalba 30: 253-269

Megaptera novaeangliae 30: 253-269
Tympano-periotic bone, toothed whales 25: 1-103
Vertebrae, baleen whales 23: 61-69
Skull and other characteristics, delphinidae 17:
93-103, 18: 171-172
Secondary sexual character
Balaenoptera PkYsa/us I 6: 29-34
Physeter catodon 20: 89-94
Karyotype
Balaenoptera borealis 20: 83-88

Anatomical and Histological study
Brain, PkYseter 6: 49-72
Stene/la 26: 245-253
Platanista 32: 105-126
Spinal cord, Eubalaena 13: 231-251
Dorsal vagal nucleus, Physeter 25: 241-249
Acoustic system 2: 1-20, 21: 95-123
Organ of hearing 2: 21-30, 8: 1-79
Labyrinth 14: 291-304
Sinus hair, Balaenoptera borealis I: 41-47
Sensory tubercle, lip 3: 1-16
Lingual margin 28: 137-140
Taste buds, Stene/la 30: 285-290
Tongue, Sirenia 32: 127-144
Head section, Stene/la 19: 105-133
Extrinsic eye muscle 6: 1-33
Masseter, Megaptera 17: 49-52
Heart, conducting system 9: 11-35
cardiac nerve, Berardius 7: 1-22
Larynx 3: 23-62
Air-sac, Histriophoca and Phoca 29: 129-135
Lung 6: 35-47
Parathyroid, Platanista 30: 281-284
Abdominal cavity, iconography 5: 17-39
Stomach 23: 91-101
Renculi 13: 253-267
Anal tonssil., Platanistidae 29: 95-100
Corpus luteum, Callorhinus 29: 121-128
Red bone marrow, B. PkYsalus 3: 17-22
Embryo, Stene/la 10: 1-68, 16: 83-87
Size of cell 13: 269-301
Epidermal cyst 31 : 93-94

Body and organ weight
Eubalaena glacialis 13: 1-52, 21: 1-78
Balaenoptera musculus 3: 132-190, 4: 184-209, 7:
125-183
B. musculus brevicauda 22: 1-27

ii

B. Physalus 3: 132-190, 4: 184-209, 7: 125-183
B. borealis 4: 1-13
B. edeni 10: 133-141
B. acutorostrata 22: 75-125
Megaptera noveangliae 7: 125-183, 14: 49-87
Physeter catodon 4: 1-13, 7: 125-183
Mesoplodon ginkgodens 24: 43-56
Lagenodelphis hosei 25: 251-263
Stenella attenuata 26: 157-226
Platanista gangetica 24: 87-108, 26: 265-270
Pontoporia blainvillei 26: 265-270
Mirounga leonina 20: 211- 212
Dugong dugon 31: 129-132

Age determination
Crystalline lens 3: 132-190, 4: 115-161
Baleen plates 4: 162-183, 6: 133-152
Ear plug 12: 23-32, 14: 107-135, 17: 37-48, 18:
29-48
Baleen whales 7: 87-119
Balaenoptera physalus 13: 155-169, 18: 49-88, 20:
17-82
Physeter catodon 13: 135-153, 17: 15-35, 20: 1-16
Berardius bairdii 29: 1-20
Tursiops truncatus 32: 39-66

Stenella coeruleoalba 8: 133-1461 24: 57-79, 28: 73106, 29: 21-48
S. attenuata 26: 157-226, 28: 73-106
Platanista gangetica 24: 87-108
Pontoporia blainviliei 31 : 45-67
Callorhinus ursinus 17: 191-195
Dugong dugon 30: 301-310

Population study
Eubalaena glacialis 13: 1-52, 21 : 1-78
Eschrichtius robustus 5: 71-79, 13: 201-205, 22: 2937, 22: 39-43, 26: 1-14
Balaenoptera musculus 3: 132-190, 4: 27-113, 5: 91167, 6: 73-131, 7: 125-183, 8: 147-213
B. physalus 3: 119-131, 3: 132-190, 4: 27-113, 5:
91-167, 6: 73-131, 7: 125-183, 8: 147-213, II:
85-98, 12: 103-125, 13: 97-133, 13: 155-169, 15:
85-142, 17: 53-65, 18: 1-27, 18: 49-88
B. borealis 3: 119-131, 4: 27-113, 9: 89-103, 22:
63-74
B. edeni 3: 106-118, 3: 119-131, 9: 89-103, 9:
165-177, 10: 79-87, 14: 1-33, 16: 7-18, 28: 135, 30: 291-300
B. acutorostrala 11: 1-37, 11: 181-189, 19: 37-43,
22: 75-125, 37-59
Megaptera novaeangliae 4: 27-113, 6: 73-131, 7:
125-183, 8: 81-102, 8: 147-213, 14: 49-87, 15:

1-16, 16: 19-28, 29: 59-85, 30: 245-247
Physeter catodon 3: 106-118, 3: 119-131, 4: 27-113,
6: 153-165, 7: 121-124, 7: 125-183, 8: 147-213,
10: 143-149, II: 39-46, 13: 135-153, 17: 15-35,
19: 1-35, 20: 1-16, 23: 1-25-?,iphius cavirostris 10: 89-132, 24: 35-41
Berardius 27: 111-137
B. bairdii 10: 89-132, 13: 213-214, 23: 111-122,
29: 1-20
Orcinus orca 13 : 85-96
Globicephala macrorhynchus and G. melaena 27: 95110
Stene/la coeruleoalba 12: 191-192, 22: 159-162, 24:
57-79, 26: 227-243, 28: 73-106, 29: 21-48, 30:
65-115S. attenuata 26: 157-226, 26: 227-243, 28: 73-106
Lagenodelphis hosei 30: 231-244
Phocoenoides dalli 30: 1-64
Neophocaena phocaenoides 31 : 1-44
Cephalorhynchus commersonii 32: 149-154
Platanista gangetica 24: 87-108, 24: 109-115, 27:
81-94, 29: 87-94
Pontoporia blainvillei 31 : 45-67
School, baleen whales 18: 89-110
Corpora albicantia 18: 123-148
Virginal band 21 : 85-94
Counting and measuring, baleen and ventral grooves
25:279-292
Baleen, function 28: 37-55
Underwater sound 23: 123-128
Epimeletic behavior 28: 141-143
Marking dolphin 20: 101-107, 24: 81-85
Human activity disturbing whales 29: 113-120
History, whaling 21: 125-129
Color pattern, Phoca 25: 301-310
Growth, Phoca 24: 127-144
Pelage, Historiophoca 28: 187-197
Occurrence, phocid seals 28: 175-185
Distribution, Phoca 31: 105-119
Dugong 31: 133-141
Diving depth, Callorhinus 24: 145-148
Wandering speed, Erignathus 31: 121-123
Serology 7:69-77, 8: 103-125, 9: 105-120, II:
85-98. 13: 171-184, 14: 89-100, 14: 101-106, 15:
85-142, 17: 53-65, 17: 67-77, 18: 1-27

Food and feeding(See also population study)
Baleen whales 5: 81-90, 12: 33-89, 13: 193-199,
14: 149-290, 16: 89-103, 17: 157-170, 19: 45-51,
20: 109-155
Balaenoptera borealis 22: 127-152, 22: 153-158, 25:

iii

219-236, 26: 25-144
B. edeni 7: 79-85, 29: 49-58, 32: 1-23
Megaptera novaeangliae 31 : 69-83
Eschrichtius robustus 22: 39-43
Physeter catodon 5: 81-90, 11: 139-151, 11: 153161, 18: 111-122, 28: 145-151, 32: 199-218
Orcinus orca 29: 107-111
Stene/la coeruleoalba 25: 265-275
Balaenopterids 32: 155-198
Antarctic fish from stomach 12: 225-233
Stone and alien from stomach 17: 83-91
Stomach content in relation to chasing time 23:
27-36
Energy budget 27: 61-79

Whaling ground, environmental
9: 179-187, II: 163-179, 12:91-101, 12:209-224,
13: 215-229, 14: 137-143, 15: 143-158, 16: 105119, 17: 105-155, 20: 157-210, 26: 271-287, 27:
141-157
Statistical review 25: 105-203
Pack-ice limit 29: 137-141
Sighting
By boat 25: 205-217, 26: 289-302, 30: 117-178,
30: 179-195
By air 23: 37-60

Parasite, scar and skin disease
Diatom 4: 14-26, 11: 99-132, 13: 185-191, 29:
101-105, 32: 97-103
Cyamus 28: 153-160
Barnacle 22: 39-43
White scar 10: 69-77, 26: 145-155
Skin disease 11: 133-138
Helminthes 11: 133-138, 28: 161-166
Marlin spear 14: 149-290 (p. 252), 22: 163-164,
25: 237-239
Aggressive encounter 31: 95-96
Parasite, Euphausia 30: 311-313

Chemical study
Enzyme, stomach I: 3-7
pancreas I: 8-10, I: 11-14, 2: 55-60, 3:
71-78
Whale meat, peptone I: 15-16
freshness I: 17-26, I: 27-30, 2: 3134, 3: 63-70, 5: 1-4, 6: 167-176,

7: 23-30, 7: 31-36, 9: 1-10
tryptophane 2: 51-54
digestion 2: 61-66
nutrition 7: 51-67
amino acid
13: 303-317, 14: 305326
methionine 3: 102-105
Whale blood I: 38-40, 3: 96-101, 5: 41-47
Whale milk 10: 151-167
Vitamin I: 31-37, 2: 35-41, 5: 53-59, 6: 187-191,
7: 47-50
Kitol 3: 85-88, 3: 89-91, 3: 92-95, 5: 49-51, 5:
61-69, 6: 193-198, 7: 47-50
Oil, gas absorption 11 : 191-213, 13: 309-321
molecular distillation 2: 42-45, 2: 46-50
Oil, Eubalarna 17: 171-190
Physeter 3: 79-84, 7: 37-46
Mirounga 12: 235-240, 13: 323-332, 20: 213221
Lipid, Eubalaena 18: 173-180
Fatty acid composition of oil,
Eubalaena 22: 165-170
Neophocaena 21: 131-135, 26: 303-306
Peponocephala 21 : 13 7-141
Platanista 23: 141-147, 24: 117-125
Inia 25: 293-299
Trichechus 26: 307-311
Krill 28: 167-174
Metal, Dugong 31: 125-128
Organochlorine compounds, Dugong 31: 125-128

Miscellaneous
Hind limb 8: 127-132, 12: 197-208, 17: 79-81,
19: 135-136
Hermaphroditism 8: 215-218
Prenatal dead fetus 16: 47-60
Malformed fetus 12: 193-195, 14: 145-147, 23:
139-140, 26: 259-263
Albino 13: 207-209
Carotinoid body color 31: 97-99
Deformed jaw 13: 211-212, 31: IOl-103
Vestigial teat 25: 277-278
Strange organ 27: 139-140
Electrocardiogram, Tursiops 15: 159-165
Electric shock 6: 177-185
Compressive strength, dentin 23: 103-110
Flattened head harpoon 6: 199-207

AUTHOR INDEX

A
Abe, H. 29: 129-13.5
Abe, T. 12: 225-233
Aguayo L., A. 28: 127-128, 30: 117-177
Akiba, T. 3: 63-70, 5: 1-4
Akikusa, S. I 0: 1.51-167
Akiya, S. I: 3-7, I: 8-10, I: 11-14, I: 15-16, 2:
51-54, 5: 41-47, 7: 23-30, 7: 31-36
Aminul Haque, A.K.M. 24: 109-11.5, 29: 87-94
Antinoja, R. C. 29: 59-8.5
Arai, Y. 7: 51-67
Arifuku, S. 2: 1-20
Asano, K. 30: 311-313
BBaba, N. 29: 121-128
Best, P. B. 32: 97-103
Bou, J. 32: 145-148
Brownell, R.L.Jr. 28: 127-128, 28: 129-135, 29:
101-105, 31: 45-67c
Calaprice, N. 17: 67-77
Casinos, A. 32: 145-148
Castello, H.P. 26: 255-258, 28: 119-126, 29:
107-111
Clarke, R. 30: 117-177
Cushing, John E. 14: 89-100, 14: 101-106, 17:
67-77
DDairokuno, A. 12: 209-224
Dawbin, W. H. 26: 157-226
de! Campo, S. B. 30: 117-177
E

ECG Research Group

15: 159-165

F
Fujino, K. 7: 67-77, 7: 125-183, 8: 103-125, 9:
89-103, 9: 105-120, 9: 121-163, 10: 89-132, 10:
133-141, 11: 47-83, 11: 85-98, 13: 171-184, 14:
89-100, 14: 101-106, IS: 85-142, 17: 53-65, 17:
67-77, 18: 1-27
Fukazawa, R. 3: 85-88, 3: 89-91, 3: 92-95, 5:
49-51
Fukushima, M. 31: 125-128
Furuno, T. 29: 137-141

IV

G

Gianuca, N. M. 28: 119-126
Goodall, R.N.P. 30: 197-232
H

Handa, C. 13 : 85-96
Hasegawa, Y. 21: 79-84, 29: 129-135
Hayashi, K. 3: 132-190
Herman, L. M. 29: 59-85
Hibiya, T. 6: 1.53-165, 7: 121-124, 9: 165-177,
22: 39-46, 13: 97-133, 13: 135-136
Hirata, M. 6: 199-207
Hirosawa, K. 21: 95-123
Hirose, S. 10: 151-167
Hiruta, H. 30: 249-151
Hohn, A. A. 32: 39-66
Honda, K. 31: 125-128
Hoshina, T. 11: 133-138
Hoshino, 0. 5: 41-47, 7: 23-30, 9: 1-10
Hosokawa, H. 3: 23-62, 5: 5-15, 6: 1-33, 10: 168, 13: 269-301, 19: 105-133, 21: 95-123, 23:
91-101
I

Ichihara, T. 12: 127-189, 13: 155-169, 13: 201205, 14: 107-135, 16: 47-60, 17: 37-48, 18: 2948, 19: 37-43, 20: 17-82, 20: 211-212, 22: 1-27,
24: 145-148
Igarashi, S. 21: 95-123
Iguchi, K. 8: 147-213
Ishikawa, S. 1: 11-14, 2:35-41, 2:42-45, 2:5560, 3: 71-78, 5: 53-59, 5: 61-69, 11: 191-213,
13: 309-321
Ishimaru, K. 32: 97-103
Ishimaru, T. 29: 101-105
Itano, K. 31: 125-128
Itoh, S. 20: 213-221, 21: 131-135, 22: 165-170,
23: 141-147, 24: 117-125, 25: 293-299, 26: 303306, 26: 307-311, 28: 167-174
Iwai, E. 11: 139-151, 11: 153-161

J
Jimbo, H. 3: 119-131
J urasz, C. M. 31 : 69-83
Jurasz, V. P. 31: 69-83

K
Kagei, N.

28: 161-166, 30: 311-313

v

Kakuwa, Z.

8: 147-213

Kamiya, T. 12: 197-208, 13: 53-83, 13: 253-267,
14: 35-48, 19: 53-64, 19: 105-133, 21: 95-123,
23: 91-101, 26: 245-253, 26: 259-263, 26: 265270, 28: 137-140, 29: 95-100, 30: 281-284, 30:
285-290, 31: 93-94, 31: 129-132, 32: 105-126, 32:
127-144
Kaneko, A. 2 : 46-50
Kanno, H. 2: 42-45
Kashita, K. 23: 139-140
Kasuya, T. 16: 35-45, 17: 15-35, 19: 37-43, 19:45-51, 19: 65-90, 20: 83-88, 20: 89-94, 21: 1-27,
22: 1-27, 22: 29-37, 22: 39-43, 22: 45-62, 23:
37-60, 23: 71-81, 23: 83-89, 23: 129-137, 24:
43-56, 24: 57-79, 24:81-85, 24:87-108, 24:
109-115, 25: 1-103, 25: 265-275, 26: 157-226,
26: 227-243, 27: 81-94, 27: 95-108, 28: 57-68,
28: 73-106, 28: 141-143, 29: 1-20, 29: 87-94, 30:
J-63, 30: 301-310, 31: 1-44, 31: 45--{)7, 31: 8592, 31: 133-141, 32: 67-95
Kataoka, T. 31: 129-132, 31: 133-141
Kato, H. 31: 97-99, 31: 101-103
Kawai, S. 31: 125-128
Kawakami, T. 7: 79-85, 8: 147-213, 28: 145-151,
32: 199-218
Kawamura, A. 22: 75-125, 22: 127-152, 23: 2736, 23: 139-140, 25: 219-236, 26: 25-144, 27:
61-79, 28: 1-35, 29: 49-58, 29: 137-141, 30:
291-303, 32: 1-23, 32: 155-198
Kihata, M. 30: 311-313
Kimura, S. 9: I 65-177, JO: 89-132, I 1: 39-46,
11: 181-189, 12: 103-125
Kijima, M. 5: 61-69
Klima, M. 30: 253-269
Kobo, F. 1: 15-16
Kojima, T. 6: 49-72
Komatsu, S. 29: 95-100, 30: 281-284, 30: 285290, 32: 127-144
Konno, S. 31: 105-109
Korostoff, E. 23: 103-110
Kureha, K. 24: 43-56, 27: 139-140, 31: 1-44
L

Leung, Y. M. 28: 153-160
Lugassy, A. A. 23: 103-1 JO
M

Machida, S. 22: 163-164, 26: 271-287, 26: 289302, 27: 141-159
Maeda, T. 17: 1-14
Major, P. F. 31: 95-96
Masaki, Y. 22: 63-74, 22: 75-125

Matsui, S. 32: 67-95
McCann, C. 26: 145-155, 27: 111-137, 28: 107117
Mermoz, J. F. 32: 149-154
Mizue, K. 3: J06-I 18, 3: 119-131, 5: 71-79, 5:
81-90, 6: 73-131, 23: 123-128, 29: 121-128
Miyazaki, N. 25: 265-275, 26: 157-226, 26: 227243, 26: 259-263, 28: 141-143, 29: 21-48, 30:
65-115, 30: 179-195, 30: 231-244, 31: 125-128,
31: 133-141
Mo!, T. 21: 125-129
Mori, T. 3: 79-84
Motohashi, N. 7: 23-30, 9: 1-10
Murata, T. 6: 35-47, 6: 73-131
N

Nagasaki, Y. 28: 161-166
Naito, Y. 24: 127-144, 25: 301-310, 26: 313-320,
28: 175-185, 28: 187-197, 31: 105-119, 31: 121123
Nakai, T. I: 17-26, 1:27-30, 1:41-47, 2:31-34,
6: 167-176, 6: 177-185, 14: 30.5-326
Nakajima, M. 17: 191-195, 19: 6.5-90, 19: 91J04, 20: JOl-J07
Naruse, U. 17: 171-190, 18: 173-180
Nasu, K. II: 163-179, 12: 91-101, 13: 193-199,
13: 211-212, 14: 137-143, 15: 143-1.58, 17: 8391, 17: 105-15.5, 20: 157-210, 22: 63-74,' 25:
205-217
Natsume, Y. 3: 63-70, 5: 1-4
Nemoto, T. JO: 67-77, 10: 79-87, I I: 99-132, I I:
181-189, 12: 33-89, 13: 97-133, 13: 185-191, 13:
193-199, 14: 149-290, 16: 29-34, 16: 89-103, 17:79-81, 17: 83-91, 17: 191-195, 18: 89-110, 18:
I I 1-122, 19: 45-51, 20: 109-15.5, 21: 1-78, 22:
153-1.58, 23: 129-137, 27: 81-94, 29: 101-105,
30: 245-247, 32: 97-103
Nishimoto, S. 7: 79-85
Nishiwaki, M. 3: 132-190, 4: 115-161, 4: 162183, 4: 184-209, 5: 91-167, 6: 133-152, 6: 153165, 7: 87-119, 7: 121-124, 8: 133-146, 8: 215218, 9: 165-177, JO: 143-149, 11:39-46, 12:2332, 12: 191-192, 12: 193-195, 13: 53-83, 13: 8596, 13: 97-133, 13: 135-153, 13: 155-169, 14:35-48, 14: 49-87, 15: 1-16, 16: 19-28, 16: 3.546, 16: 61-77, 16: 79-82, 17: 1-14, 17: 15-35,
17: 93-103, 17: 191-195, 18: 171-172, 19: 53-64,
19: 65-90, 19: 91-104, 20: 95-100, 20: 101-107,
20:211-212, 21:79-84, 22:29-37, 22:45-62,
22: 1.59-162, 23: 71-81, 23:83-89, 23: 111-122,
23: 123-128, 23: 129-137, 24: 35-41, 24: 43-56,
24: 127-144, 25: 251-263, 25: 265-275, 25: 277-

vi
278, 26: 227-243, 27: 81-94, 27: 139-140, 29:
87-94, 29: I 13-120, 30: 65-115, 30: 301-310, 31:
93-94, 31: 133-141
Norris, K. S. 20: 95-1000Ogawa, T. 2: 1-20, 3: 1-16, 7: 1-22, 8: 127-132,
9: 11-35, 12: 197-208, 13: 303-307
Oguro, N. 23: 111-122, 24: 43-56, 24: 81-85
Ohe, T. 3: 17-22, 5: 17-39, 5: 91-107
Ohno, M. 7: 125-183
Oshima, M. 28: 187-197
Ohsumi, S. (Kimura) 13: 97-133, 13: 135-153, 13:
155-169, 13: 207-209, 14: 145-147, 15: 17-84,
17: 1-14, 17: 15-35, 18: 49-88, 18: 123-148, 19:
1-35, 19: 135-136, 20: 1-16, 20: 89-94, 21: 1-78,
21: 85-94, 22: 75-125, 23: 1-25, 25: 237-239
Ohta, K. 10: 151-167
Oishi, Y. 10: 151-167
Okano, K. 10: 151-167
Okuda, H. 5: 53-59
Okutani, T. 18: 111-122
Omote, Y. 2: 35-41, 2: 42-45, 5: 53-59, 5: 6169, 6: 187-191, 6: 193-198, 7: 47-50
Omura, H. 4: 1-13, 4: 14-26, 4: 27-113, 8: 81102, 9: 89-103, 10: 79-87, 10: 89-132, 11: 1-37,
12: 1-21, 13: 1-52, 13: 213-214, 14: 1-33, 16:
1-5, 16: 7-18, 16: 35-45, 18: 149-170, 21: 1-78,
22: i-27, 23: 61-69, 23: 71-81, 24: 1-34, 25:
105-203, 26: 1-14, 26: 15-24, 27: 1-36, 28: 5768, 28: 69-72, 30: 271-279, 31: 85-92' 32: 25-37
Ono, H. 6: 177-185
Osawa, M. 13: 303-307
Oya, M. 29: 121-128p

Panizza, J. S. 26: 255-258
Pirlot, P. 26: 245-253, 32: 105-126
Pivorunas, A. 28: 37-55
Praderi, R. 28: 129-135

Sato, M. 10: 1.51-167
Satomi, M. 28: 137-140
Sawamura, R. 7: 31-36
Seki, Y. 13: 231-2.51, 25: 241-249
Sekino, T. 13: 269-301
Shida, T. I: 41-47, 3: 1-16
Soma, Y. 2: 35-41
Sugiura, Y. II: 133-138
Suzuki, T. 13: 215-229, 17: 49-.52
TTakahashi, K. 2: .51-.54, 14: 89-100
Takano, H. 32: 97-103
Takao, M. 7: 37-46
Takemura, A. 23: 123-128
Tanzawa, T. I: 8-10
Tawara, T. I: 31-37, I: 38-40, 3: 85-88, 3: 8991, 3: 92-9.5, 3: 96-101, 5: 49-51
Tejima, S. 1:3-7, 1:8-10, I: 11-14, 2:.55-60
Tobayama, T. 19: 6.5-90, 20: 101-107, 22: 1.59162, 25: 2.51-263, 28:. 161-166, 29: 87-94, 31:
93-94, 31: 113-141
Tokita, K. 1.5: 1.59-165
Torno, A. P. 26: 25.5-2.58
Torres, N. D. 28: 127-128
Tozawa, H. 7: 79-8.5
Tsuchiya, T. 3: 63-70
Tsukamoto, S. 2: 61-66
Tsunoda, T. 13: 303-307
Tsuyuki, H. 12: 235-240, I 3: 323-332, 17: 171190, 18: I 73-180, 20: 213-221, 21: 131-13.5, 21:
137-141, 22: 165-170, 23: 141-147, 24: 117-125,
2.5: 293-299, 26: 303-306, 26: 307-31 I, 28: 167174

uUchida, S. 22: 159-162, 31: 129-132
Ueshiba, Y. 10: 151-167
Uda, M. 9: 179-187, 11: 163-179, 12: 209-224,
13: 21.5-229, 16: 10.5-119
Umehara, M. 3: 63-70, 5: 1-4v

R

Rabinowits, .J. L. 23: 103-110
Rice, D. W. 22: 39-43s
Saiki, M. 3: 79-84
Sakai, S. 7: .51-67
Sakiura, H. 11: 1-37
Sasao, A. 29: 113-120
Satake, Y. 26: 1.5-24, 28: 1-35

van Bree, P.J.H.

21: 125-129

w
Wada, K. 29: 129-135
Wada, S. 30: 179-19.5, 30: 233-246
Watari, T. 10: 1.51-167
Williamson, G. R. 2.5: 279-292, 27: 37-.59

viiyYagi, T. 8: 133-146, 17: 191-195• 32: 127-144
Yamada, M. 2: 21-30, 8: 1-79, 9: 37-58, 9: 5988, 14: 291-304
Yamaguchi, K. 7: 69-77
Yamamoto, Y. 30: 249-251
Yamasaki, F. 26: 265-270, 28: 137-140, 29: 95-

100, 30: 283-286, 30: 289-292, 32: 127-144
Yang, H. C. 25: 251-263
Yonekura, M. 32: 67-95
Yoo, K. I. 22: 153-158
Yoshida, K. 24: 145-148, 29: 121-128
Yoshida, M. 3: 102-105
Yoshizaki, F. 14: 291-304
Yoshikawa, T. 10: 151-167, 17: 49-52

a:g fJJ 55 if. 12 JJ 15 13 FD ,mrJ
a:g 'fj] 55 if. 12 jJ 30 13 Ja :ff

*i •

*

*i'1lJ'Nf:ilr
FD ,mrJ ;g.

Jl;fB'!Ji:tA!Yffi

13 :<$: till ,(tjj\ ~ #;;

2M

1iJf

'.9G

m

*ffi~~*g~~~lT§3*1%

tf* t± F!J~Jf '.9G

Jfj

it,\jllj ;f* ~ ~ t±*ffi~*'f~gtifl~:f:EO T§ 2*!11!

Printed by
Kenkyusha Printing Co.
Shinjuku-ku, Tokyo

:if ftffi 4,000 p:]

Obtainable from Japan Publication Trading Co. Ltd.,
Sarugakucho, Chiyoda-ku, 1-2-1, Tokyo 101