SC/52/E6

Regional assessments of prey consumption by marine
cetaceans in the world
Tsutomu Tamura and Seiji Ohsumi
The Institute of Cetacean Research, 4-18 Toyomi-cho, Chuo-ku, Tokyo 104-0055, Japan

ABSTRACTThe total annual prey consumption by 37 species out of 75 species of marine cetaceans in the world wasassessed. The assessment was based on 1) recently available abundance estimates of cetaceans, 2) daily
prey consumption rates of cetaceans estimated by use of three methods, 3) estimated biomass of cetaceans
by use of average body weight and abundance, and 4) composition of prey species of cetaceans. The
annual prey consumption of cetaceans was estimated for three ocean regions, the Southern Hemisphereincluding the Indian Ocean (121-245 million tons), the North Pacific (62-85 million tons) and the North
Atlantic (55-107 million tons). Total annual prey consumption by cetaceans in the world was estimated tobe 249-436 million tons as the minimum, because our data are not covered on all cetacean species andwhole the distribution areas of them. The fish consumption by cetaceans in the Southern Hemisphereincluding the Indian Ocean was estimated to be 18-32 million tons and accounted for 66-120% ofcommercial fisheries catches in 1996. In the case of the North Pacific, the fish consumption was
estimated to be 21-30 million tons and accounted for 66-96% of commercial fisheries catches in 1996. In
the North Atlantic, the fish consumption by cetaceans was 15-25 million tons and accounted for 87-144%of commercial fisheries catches in 1996. We consider that at least, there was probably direct competition
between cetaceans and commercial fisheries in the North Pacific and the North Atlantic . However, as theinformation on the abundance of cetaceans was not included for all species, the actual figures of annual
prey consumption by all cetaceans are most probably larger than present results. More information ofabundance, body weight and prey composition of cetaceans in each region is necessary to consider
comp etition between cetaceans and commercial fisheries in order to address a more realistic for strategy
fisheries management and the conservation of cetaceans in future.
KEYWORDS:
PREY, PREY CONSUMPTION, ENERGETICS, CETACEANS, SOUTHERN HEMISPHERE, NORTHPACIFIC, NORTH ATLANTIC, WORLDINTRODUCTION
Seventy-nine species of cetaceans (whales, dolphins and porpoises) inhabit in the world, among which 75
species live in the sea. As cetaceans are mammals, they need a large amount of energy to keep their body
temp erature in the environment of water. Thus, they must consume large amounts of prey.
The cetaceans are top predators of the food web, playing an important role in the marine ecosystem. It
is important to elucidate the total prey consumption of cetaceans in the world, because these results canprovide information useful to address the issue of long term sustainability of marine living resources. Thiskind of work is practically difficult, because the data available are incomplete and many assumptions are1needed for this sort of study. The quantitative data on feeding ecology of top predators are insufficient.
Some researchers have estimated the food consumption by cetaceans based on techniques such asenergy-requirements calculations (Hinga, 1979; Lockyer, 1981; Innes et al., 1986; Armstrong andSiegfried, 1991; Sigurjónsson and Víkingsson, 1998; Tamura and Fujise, 2000b).
Furthermore, in recent years, some researchers tried to understand the competition between fish stockand cetaceans in small areas based on the statistical simulation model.
Tamura and Ohsumi (1999) tried to estimate the total prey consumption by marine cetaceans in theworld. They reported that total prey consumption of cetaceans was 279-498 million tons, which wereequivalent to three to six times of the total catch by marine commercial fisheries in recent years.
Young (1999) reported the potential for impact of large whales on commercially fishing in the South
Pacific Ocean. He reported the large whales in the Southern Hemisphere fed on krill, and dietary overlap
with commercial by fished species was relatively low. He noted that any assessment of interactions
between cetacean and fisheries was limited by a lack of qualitative and quantitative data in the South
Pacific Ocean.
Tamura and Ohsumi’s paper was introduced in the Scientific Committee of the IWC (IWC/SC) in 1999
and there were some comments as follows:
1. There are some unreliable data of the estimates of abundance of cetaceans. Furthermore, someestimates of the abundance of cetaceans used in this paper are old.
2. The species composition of the prey taken by cetaceans is not presented.
The IWC/SC agreed that the subjects discussed in these papers were important, but there was noconsensus on whether any conclusions could be drawn from them regarding the likely or potential direct
or indirect competitive impact of cetaceans on fisheries. It agreed that these topics should be considered at
a future meeting of the Committee (IWC, in press). An intersessional working group was established for
the Committee's work on these topics over the next two years, and a major was consideration planned for2001.
In this study, we again assessed the daily and annual prey consumption of marine cetaceans based on
newly available and recent abundance estimates, new average body weight of each species and threemethods used previously (Tamura and Ohsumi, 1999). This assessment was carried out for three regions;
the Southern Hemisphere including Indian Ocean (SHIO), the North Pacific (NP) and the North Atlantic(NA).
In addition, we estimated the annual prey consumption of cetaceans by prey categories using assumed
composition ratios. Finally, we considered the competition between cetaceans and fisheries at present ineach region.

MATERIALS AND METHODS
Available abundance estimates
The IWC/SC uses the estimates of current abundance based on direct methods such as sighting surveys orother methods that do not depend on catch data, such as photo-identification. However, such available
data were limited for species and regions, and some of them were old. For this study, we tried to find as
many as possible abundance estimates of cetacean in each region. We evaluated and obtained theabundance figures as current and reasonable as possible from published sources for calculating thebiomass of cetaceans.
Southern Hemisphere including Indian Ocean
The figures on abundance of 15 species out of 55 species of marine cetaceans distributing in this region
are shown in Table 1-1.

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Blue whale (Balaenoptera musculus): There are two sub-species of blue whale in the study region. The
most current abundance is 1,255 true blue whales (no CV available) based on combining data of
IWC/IDCR cruises from 1978/79 to 1987/88 (IWC, 1996), and pigmy blue whale abundance wasestimated at 5,000 individuals in the mid 1970’s (no CV available) (Gambell, 1976). We used these two
estimates (1,255 and 5,000) for calculation of biomass.
Fin whale (Balaenoptera physalus): The IWC has calculated an abundance of 85,200 individuals (noCV available) based on the history of catches and trends in CPUE (IWC, 1979). Another estimate is
15,178 individuals based on combining data of IWC/IDCR cruises from 1978/79 to 1987/88 (Butterworth
et al. 1994; IWC, 1996). We used former estimate for calculation of biomass, because the IDCR cruises
did not cover all the life range of this species, so that the figure by the IDCR was underestimated.
Sei whale (Balaenoptera borealis): The current abundance ranged from 9,720 to 12,000 individuals (noCV available) based on the history of catches and trends in CPUE (IWC, 1980; Mizroch et al., 1984;
Perry et al. 1999). We used an average estimate (10,860 individuals) for calculation of biomass.
Bryde’s whale (Balaenoptera edeni): The most current abundance is 89,000 individuals (no CV
available) based on the accumulated sightings data from 1976/77 to 1979/80 (Ohsumi, 1981).
Minke whale (Balaenoptera acutorostrata): The current abundance is 761,000 individuals (95%
confidence interval of 510,000-1,140,000) based on combining data of IWC/IDCR cruises from 1982/83
to 1988/89 (IWC, 1991a). The IWC has recognized this estimate is the best estimate of the current
abundance within the south of 60o S during the summer. We used this estimate for calculation of biomass.
Humpback whale (Megaptera novaeangliae): The most current abundance is 10,000 individuals (95%
C.I. 5,900-16,800) based on combining data of IWC/IDCR-SOWER surveys from 1985/86 to 1990/91.
The IWC has recognized this is the best estimate of the current abundance (IWC, in press). We used thisestimate for calculation of biomass.
Southern right whale (Eubalaena australis): The Workshop on the Comprehensive Assessment of Right
Whales (IWC, 1998) emphasized that the current best estimated abundance is preferably expressed as“about 7,000” individuals. We used this estimate for calculation of biomass.
Sperm whale (Physeter macrocephalus): The current abundance ranged from 128,000 to 290,000
individuals (CV=0.44-0.46) within the south of 30o S from combining data using IWC/IDCR surveys
from 1978/79 to 1990/91 (Butterworth et al., 1994; IWC, 1995). These numbers most likely represent alarge proportion of male whales. We used an average estimate (209,000 individuals) for calculation of
biomass. However, the abundance is under-biased. Because, these numbers represent abundance only in
the Antarctic, while species distribute in all oceans from equatorial waters to the Polar Regions.
Beaked whales: Arnoux’s beaked whale (Berardius arnuxii) and southern bottlenose whale(Hyperoodon planifrons) were included in this category. The current abundance is 599,000 individuals(95% C.I. 450,000-800,000) south of 50o S from combining data using IWC/IDCR surveys from 1976/77
to 1987/88 (Kasamatsu and Joyce, 1995). We used this estimate for calculation of biomass. However,these beaked whales distribute south of 30o S, and therefore, this abundance is an underestimate.
Killer whale (Orcinus orca): The abundance are 53,000 and 64,000 individuals (CV=0.30) in south of
60o S from combining data using IWC/IDCR surveys from 1978/79 to 1990/91 (Butterworth et al., 1994;
IWC, 1995). We used an average estimate (58,500 individuals) for calculation of biomass. However,killer whales distribute in all oceans from equatorial waters to the Polar Regions, and therefore theestimate is under-biased.
Long-finned pilot whale (Globicephala melas): The abundance are 43,000 and 130,000 individuals(CV=0.80-1.04) south of 60o S from combining data using IWC/IDCR surveys from 1978/79 to 1990/91(Butterworth et al., 1994; IWC, 1995). We used an average estimate (86,500 individuals) for calculationof biomass. However, the abundance is under-biased, because long-finned pilot whales distribute in southof 30o S in the Southern Hemisphere.

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Hourglass dolphin (Lagenorhynchus cruciger): The current abundance is 144,000 individuals (95% C.I.
100,000-200,000) south of 50o S from combining data using IWC/IDCR surveys from 1976/77 to
1987/88 (Kasamatsu and Joyce, 1995). We used this estimate for calculation of biomass.
Commerson’s dolphin (Cephalorhynchus commersonii): The current abundance is 3,211 individuals(no CV) from the Magellan Strait (Letherwood et al. 1988). We used this estimate for calculation of
biomass.
Hector’s dolphin (Cephalorhynchus hectori): The current abundance is 3,408 individuals (no CV)
around New Zealand (Dawson and Slooten, 1988). We used this estimate for calculation of biomass.
There are many other cetacean species in the Southern Hemisphere of which information on theabundance has not yet available. When abundance estimates are available, even in the same cetacean
species, the research area for whale sightings has not covered the whole of its distribution range. For
almost all the available abundance, the research areas that were in the waters of south of 60o S. Especiallythe knowledge on abundance of cetaceans in the Indian Ocean is scarce.
North Pacific
The figures on abundance of 25 species out of 40 species of marine cetaceans distributing in this region
are shown in Table 1-2.
Blue whale: Wade and Gerrodette (1993) estimated 1,415 individuals (CV=0.24) in the eastern tropical
Pacific. Perry et al. (1999) described that at a minimum there are currently over 3,300 blue whales in the
North Pacific. We used 3,300 individuals for calculation of biomass.
Fin whale: The current abundance ranged from 14,620 to 18,630 individuals in the entire North Pacificbased on the history of catches and trends in CPUE (Braham, 1991). We used an average estimate (16,125
individuals) for calculation of biomass.
Sei whale: The current abundance is 9,110 individuals (no CV available) based on the history ofcatches and trends in CPUE (Tillman, 1977). We used this estimate for calculation of biomass.
Bryde’s whale : The current abundance is 21,901 whales based on the ship-based line transect survey
data in the western North Pacific (Shimada and Miyashita, 1997; IWC, 1997b). The other available
abundance estimate is 13,023 (CV=0.20) whales based on the ship-based sighting survey data in theeastern tropical Pacific (Wade and Gerrodette, 1993). We used a sum estimate (34,924 individuals) for
calculation of biomass.
Minke whale: The current abundance is 25,000 individuals (95% C.I. 12,800-48,600) for the Okhotsk
Sea-West Pacific stock (IWC, 1992b) and the current abundance is 7,600 individuals (CV=0.40) for the
Sea of Japan stock (IWC, 1984). The IWC has recognized this is the best estimate of the present
abundance for the Okhotsk Sea-West Pacific stock (IWC, 1992b). We used a sum estimate (32,600
individuals) for calculation of biomass. This species also distributes in the eastern North Pacific, but noavailable information was obtained. The information on minke whale abundance in this region should bemade available in the future.
Humpback whale: The most current abundance ranged from 6,000 to 8,000 individuals based on using
photo-identification methods, but considering statistical biases and separated regional estimates(Calambokidis et al. 1997), Perry et al. (1999) described that the true abundance is likely to be higher
than this figure. We used 7,000 individuals as the average for calculation of biomass.
Northern right whale (Eubalaena glacialis): The current abundance ranged from 100 to 500 individuals
in the eastern North Pacific and the current abundance is 900 individuals (95% C.I. 404-2,108) in the Seaof Okhotsk (IWC, 1998). We used a sum estimate (1,200 individuals) for calculation of biomass.
Bowhead whale (Balaena mysticetus): The current abundance is 7,500 individuals (95% C.I.
6,400-9,200) in the Bering-Chukchi-Beaufort Seas stock. The IWC has recognized this is the best
estimate of the present abundance (Raftery and Zeh, 1991; IWC, 1992a). We used this estimate for4calculation of biomass.
Gray whale (Eschrichtius robustus): It is reported that their recent number is being estimated with
26,300 (95% C.I. 21,900-32,400) individuals and be increasing with 3.2% of year rate in the eastern
North Pacific stock (Hobbs and Rugh, 1999). The IWC has recognized this is the best estimate of thecurrent abundance for this stock (IWC, in press). We used this estimate for calculation of biomass.
However, there are additionally some hundred estimates for western Pacific stock.
Sperm whale: Kato and Miyashita (1998) estimated 102,112 individuals (CV=0.16) based on Japanese
Sighting Vessels surveys from 1982 to 1996 in western North Pacific. Another abundance is 22,666(CV=0.22) whales based on the ship-based sighting survey data in the eastern tropical Pacific (Wade andGerrodette, 1993). We used a sum estimate (124,778 individuals) for calculation of biomass. However,the sperm whales distribute in all oceans from equatorial waters to the polar seas, and therefore theabundance that we used is under-biased.
Dwarf sperm whale (Kogia simus): The abundance is 11,215 individuals (CV=0.29) based on the
ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used thisestimate for calculation of biomass, though this is under-biased because the dwarf sperm whales distributein the entire North Pacific.
Baird ’s beaked whale (Berardius bairdii): The estimated abundance is 3,950 individuals (CV=0.28) in
the Pacific coast of Japan based on sighting and effort data using Japanese Sighting Vessels surveys from1983 to 1989. The population size in the Sea of Japan and the Okhotsk Sea were preliminarily estimatedas 1,260 (CV=0.45) and 660 (CV=0.27) whales, respectively (Miyashita, 1990). We used a sum estimate(5,870 individuals) fo r calculation of biomass. However, the Baird’s beaked whales distribute in the entire
North Pacific, Sea of Japan, Okhotsk Sea and Bering Sea, these estimates are underestimates.
Cuvier’s beaked whale (Ziphius cavirostris): The abundance is 20,000 individuals (CV=0.27) whales
based on the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993).
We used this estimate for calculation of biomass. However, this estimate is under-biased, because theCuvier’s beaked whales distribute in the entire North Pacific.
Killer whale: The current abundance is 8,500 (CV=0.37) whales based on the ship-based sighting
survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used this estimate forcalculation of biomass. However, the killer whales distribute in the entire North Pacific. Above estimate
seems to be only a part of the large number in the North Pacific.
Short-finned pilot whale (Globicephala macrorhynchus): The most current abundance is 53,608
individuals (95% C.I. 34,723-82,756) in the western North Pacific based on sighting and effort data using
Japanese Sighting Vessels from 1983 to 1991 (Miyashita, 1993a). We used this estimate for calculation of
biomass. However, this estimate is under-biased, because, short-finned pilot whales distribute in the entire
North Pacific.
False killer whale (Pseudorca crassidens): The most current abundance is 16,668 individuals (95% C.I.
10,034-27,689) in the western North Pacific based on combining data using Japanes e Sighting Vessels
surveys from 1983 to 1991 (Miyashita, 1993a). Another abundance is 39,800 (CV=0.64) whales based on
the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used asum estimate (56,468 individuals) for calculation of biomass. However, false killer whales distribute in
the southern part of the North Pacific, and therefore the estimate is under-biased.
Pygmy killer whale (Feresa attenuata): The current abundance is 38,900 (CV=0.31) whales based on
the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used
this estimate for calculation of biomass. However, the abundance is under-biased, because the pygmy
killer whales distribute in the entire North Pacific.
Melon-headed whale (Peponocephala electra ): The current abundance is 45,400 (CV=0.47) whales
based on the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993).

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We used this estimate for calculation of biomass. As well, the melon-headed whales distribute in theentire North Pacific; this estimate seems to be under-biased.
Rough-toothed whale (Steno bredanensis): The current abundance is 145,900 (CV=0.32) whales basedon the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We
used this estimate for calculation of biomass. However, this estimate is under-biased, because therough-toothed whales distribute in the entire North Pacific.
Pacific white-sided dolphin (Lagenorhynchus obliquidens): The most current abundance is 988,000
individuals (95% C.I. 164,000-6,790,000) in the North Pacific based on combining data using Japanesesighting Vessels surveys from 1983 to 1990 (Miyashita, 1993b). We used this estimate for calculation of
biomass.
Risso’s dolphin (Grampus griseus): Estimated abundance for the western North Pacific is 83,289
individuals (95% C.I. 58,764-118,049) based on combining data using Japanese sighting vessels surveys
from 1983 to 1991 (Miyashita, 1993a). Another abundance was 289,300 individuals (CV=0.34) based on
the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used asum estimate (372,589 individuals) for calculation of biomass.
Bottlenose dolphin (Tursiops truncatus): Estimated abundance is 168,791 individuals (95% C.I.
102,000-279,044) in the western North Pacific based on combining data using Japanese Sighting Vessels
surveys from 1983 to 1990 (Miyashita, 1993a). Another abundance is 243,500 (CV=0.29) whales basedon the ship-based sighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We
used a sum estimate (412,291 individuals) for calculation of biomass.
Pantropical spotted dolphin (Stenella attenuata): The most current abundance are 730,900 individuals(CV=0.14) of Northeastern, 1,298,400 individuals (CV=0.15) of Western/southern and 29,800 individuals(CV=0.35) of Coastal based on the ship-based sighting survey data in the eastern tropical Pacific (Wadeand Gerrodette, 1993). Another abundance was 438,064 individuals (95% C.I. 312,285-614,503) in thewestern North Pacific based on combining data using Japanese Sighting Vessels surveys from 1983 to
1990 (Miyashita, 1993a). We used a sum estimate (2,497,164 individuals) for calculation of biomass.
However, pantropical spotted dolphins distribute in the southern part of North Pacific (south of 40o N), so
this estimate is under-biased.
Spinner dolphin (Stenella longirostris): The most current abundance are 631,800 individuals(CV=0.24) of eastern and 1,019,300 individuals (CV=0.19) of whitebelly area based on the ship-basedsighting survey data in the eastern tropical Pacific (Wade and Gerrodette, 1993). We used a sum estimate(1,651,100 individuals) for calculation of biomass. However, spinner dolphins distribute in the southernpart of North Pacific (south of 40o N), and this number is an underestimate.
Striped dolphin (Stenella coeruleoalba): The most current abundance is 1,918,000 individuals(CV=0.11) based on the ship-based sighting survey data in the eastern tropical Pacific (Wade andGerrodette, 1993). And, the other abundance was 570,038 individuals (95% C.I. 397,435-817,602) in thewestern North Pacific based on combining data using Japanese sighting vessels surveys from 1983 to
1990 (Miyashita, 1993a). We used a sum estimate (2,488,038 individual) for calculation of biomass.
Common dolphin (Delphinus delphis): The most current abundance are 476,300 individuals (CV=0.37)
of Northern, 406,100 individuals (CV=0.38) of Central and 2,210,900 individuals (CV=0.22) of Southernin the eastern tropical Pacific based on the ship-based sighting survey data from 1986 to 1990 (Wade andGerrodette, 1993). We used a sum estimate (2,664,300 individuals) for calculation of biomass. However,this abundance estimate is an underestimate, because common dolphins distribute in the southern part ofNorth Pacific (south of 50o N).
Fraser’s dolphin (Lagenodelphis hosei): The abundance estimate is 289,300 individuals (CV=0.34) inthe eastern tropical Pacific based on Sighting Vessels surveys from 1986 to 1990 (Wade and Gerrodette,1993). We used this estimate for calculation of biomass. However, Fraser’s dolphins distribute in the6southern part of the North Pacific (south of 30o N), this estimate seems to be under-biased.
Northern right whale dolphin (Lissodelphis borealis): Estimated abundance is 308,000 individuals(95% C.I. 59,000-1,680,000) in the North Pacific based on combining data using Japanese Sighting
Vessels surveys from 1983 to 1990 (Miyashita, 1993b). We used this estimate for calculation of biomass.
Dall’s porpoise (Phocoenoides dalli): The most current abundance estimate are 1,186,000 individuals(95% C.I. 991,000-1,420,000) of Pacific and 554,000 individuals (no CV) of Okhotsk in the western
North Pacific (Miyashita, 1991; Buckland et al., 1993; IWC, 1993). We used a sum (1,740,000
individuals) for calculation of biomass. However, this abundance estimate is an underestimate, because
Dall’s porpoises distribute in the northern part of the North Pacific (north of 30o N).
Finless porpoise (Neophocaena phocaenoides): Estimated abundance is 5,000 individuals (no CV) in
Seto Inland Sea (Kasuya and Kureha, 1979). We used this estimate for calculation of biomass. However,finless porpoise also distributes in other regions. This estimate is under-biased.
White whale (Delphinapterus leucas): the abundance estimate are 5,800 individuals (no CV) for
Alaska and 27,000 individuals (no CV) for USSR (IWC, 1992c). We used a sum estimate (32,800
individuals) for calculation of biomass.
There is many other cetacean species distributing in the North Pacific for which information on theabundance has not been produced yet. Reliable estimates for baleen whales are insufficient, too. We needto have more abundance information of cetaceans based on the direct methods such as sighting surveys infuture.
North Atlantic
The figures on abundance of 19 species out of 39 species of marine cetaceans distributing in this region
are shown in Table 1-3.
Blue whale: The most current abundance is ranging from 100 to 560 individuals based on the history ofcatches and trends in CPUE (Braham, 1991). In the Gulf of St. Lawrence, the most current abundance is
320 individuals based on using photo-identification methods (Sears et al., 1990). There is no statisticallyreliable estimate in the eastern North Atlantic. We used 330 individuals for calculation of biomass as theminimum value.
Fin whale: The current abundance is 47,300 whales (95% C.I. 27,723-82,031) based on the ship-basedline transect survey data (IWC, 1992d). The IWC has recognized this is the best estimate of the present
abundance. We used this estimate for calculation of biomass.
Sei whale: The current abundance is 4,000 individuals (no CV) based on the history of catches andtrends in CPUE (Braham, 1991). We used this estimate for calculation of biomass.
Bryde’s whale: There is no statistically reliable estimate of abundance in the North Atlantic. We
omitted this species from the calculation of abundance.
Minke whale: The current abundance are 118,299 individuals (95% C.I. 96,681-144,750) for North
Eastern Atlantic, 28,000 individuals (95% C.I. 21,600-31,400) for Central Atlantic and 3,266 individuals(95% C.I. 1,790-5,950) for West Greenland (IWC, 1991b; 1997a). The IWC has recognized theseestimates are the best estimate of the present abundance. We used a sum estimate (149,000 individuals)
for calculation of biomass.
Humpback whale: The current abundance is 5,561 individuals of west of Greenland based on using
photo-identification methods (IWC, 1986b). The IWC has recognized this estimate is the best estimate of
the present abundance. However, Smith et al. (1999) estimated 10,600 humpback whales (95% C.I.
9,300-12,100) based on mark recapture analysis of photo-identification methods in the North Atlantic. We
used this estimate for calculation of biomass.
Northern right whale: The current abundance ranged from 300 to 500 individuals in the western North
Atlantic (IWC, 1986a). We used the average estimate (400 individuals) for calculation of biomass.

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Bowhead whale: Estimated abundance is 450 individuals (no CV) (Zeh et al, 1993). We used thisestimate for calculation of biomass.
Sperm whale: Rice (1989) calculated the current abundance estimates in three regions (Southern
Hemisphere, North Pacific and North Atlantic), He calculated their abundance in North Atlantic as
190,000 individuals (no CV). Estimated abundance is also 190,000 individuals (no CV) for entire North
Atlantic based on the history of catches and trends in CPUE (Odell, 1992). There is no other statisticallyreliable estimated abundance in the North Atlantic. We used this estimate for calculation of biomass.
Northern bottlenose whale (Hyperoodon ampullatus): The current abundance is 44,300 individuals for
Iceland based on using photo-identification methods (Sigurjónsson and Víkingsson, 1998). We used thisestimate for calculation of biomass.
Killer whale: The current abundance estimate is 5,500 (no CV) individuals in the Iceland based on dataof Sighting Vessels surveys in 1987 (Sigurjónsson and Víkingsson, 1998). We used this estimate forcalculation of biomass. However, the Killer whales distribute in the entire North Atlantic, so this estimate
is under-biased.
Long-finned pilot whale: The current abundance estimate is 778,000 individuals (95% C.I.
440,000-1,370,000) based on Sighting Vessels Surveys in 1987 and 1989 in the central and eastern North
Atlantic (Buckland, et al., 1992; IWC, 1993). The IW C has recognized this is the best estimate of thepresent abundance. We used this estimate for calculation of biomass. However, this estimate isunder-biased, because this did not include the western and southern Atlantic areas.
White-beaked dolphin (Lagenorhynchus albirostris): The current abundance estimate is 13,420
individuals in Iceland based on data of Sighting Vessels surveys in 1987 (Sigurjónsson and Víkingsson,1998). We used this estimate for calculation of biomass.
Atlantic white-sided dolphin (Lagenorhynchus acutus): The current abundance estimate is 38,680
individuals in Iceland based on data of Sighting Vessels surveys in 1987 (Sigurjónsson and Víkingsson,1998). We used this estimate for calculation of biomass.
Harbour porpoise (Phocoena phocoena): Estimated abundance is 28,510 individuals in Iceland basedon data of Sighting Vessels surveys in 1987 (Sigurjónsson and Víkingsson, 1998). We used this estimate
for calculation of biomass.
White whale: Estimated abundance are 45,700 individuals (no CV) of Canada and 9,500 individuals(no CV) of USSR (IWC, 1992c). We used a sum estimate (55,200 individuals) for calculation of biomass.
Narwhal (Monodon monoceros): Estimated abundance were 28,000 individuals (22,000-33,500) for
Canada-Greenland and 1,300 individuals (no CV) for Northern Hudson Bay (IWC, 1992c). We used asum estimate (29,300 individuals) for calculation of biomass.
In the North Atlantic, there are many other cetacean species for which information on the abundance
has not y et made available. Even in the cetacean species where with information exists, the research area
for the sightings has not covered the whole of its distribution range. For many small cetaceans, there are a
few abundance estimates in the North Atlantic. We need the more abundance information of cetaceans
based on direct methods such as sighting surveys in the future.
Estimation of biomass of cetaceans based on abundance and average body weight
We used newly available and recent figures of abundance estimates on each cetacean species frompublished sources, and estimated their average body weights by use of the formula by Trites and Pauly(1998). They estimated the mean body weight by sex in each species. In this study, we applied theaverage weight of male and female for cetaceans excluding sperm whales in the Southern Hemisphere.
For sperm whales in the Southern Hemisphere, we applied the average weight of male. Biomass of eachcetacean species in three ocean regions was calculated with these data by multiplying the abundance andaverage body weight.

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Estimation of daily prey consumption of cetaceans
We calculated daily prey consumption using the rate of prey intake per body weight of each cetacean
species per day (feeding rate: % of body weight) and average body weight. This terminology of 'thefeeding rate' was proposed by Sergeant (1969). Some researchers have estimated the prey consumption bycetaceans on the basis of energy–requirement (e.g. Hinga, 1979, Lockyer, 1981, Armstrong and Siegfried,
1991; Tamura and Fujise, 2000b). In this study, we estimated the daily prey consumption and feeding rateby each cetacean species based on the following three methods.
Method-1 Estimation of daily prey consumption from average body weight
Innes et al.(1986) proposed the following method to estimate daily prey consumption of a cetacean fromits average body weight:
I = 0.42M0.67(1)

where I is daily prey consumption (kg per day) and M is average body weight (kg).
Method-2 Estimation of daily prey consumption from the standard metabolism
Sigurjónsson and Víkingsson (1998) proposed a method for estimation of daily prey consumption fromthe standard metabolism of each cetacean species. The daily prey consumption is given by:
D = 206.25M0.783 ; I = D/ 1,110.3 (for baleen whales in Southern Hemisphere)
D = 206.25M0.783 ; I = D/ 1,300(for baleen whales in Northern Hemisphere and toothed whales in the world)

(2)

(3)

where D is daily caloric value of prey intake (kcal per day), M is average body weight (kg) and I is daily
prey consumption (kg). We assumed that estimated caloric values of prey were 1,110.3 kcal/kg for baleen
whales in Southern Hemisphere (Clark, 1980) and 1,300 kcal/kg for baleen whales in Northern
Hemisphere and toothed whales in the world (Steimle and Terranova, 1985).
Method-3 Estimation of daily prey consumption from Klumov’s formula
Klumov (1963) proposed a method for estimating daily prey consumption from the average body weightof each cetacean species. The daily prey consumption is given in the following formula by him:
I = 0.035M(4)

where I is daily prey consumption (kg per day), M is average body weight (kg)
Estimation of annual prey consumption of cetaceans
We recalculated the annual prey consumption (C) by each cetacean species in three ocean regions fromavailable abundance estimates (N) and daily prey consumption rates (I) obtained from above threemethods by use of the following formula:C = 365 N I(5)9Composition of prey species
Moreover, we calculated the annual prey consumption in each prey category using the assumed preycomposition (% of weight) in each region from published sources (e.g. Pauly et al., 1998). Pauly et al.
(1998) categorized marine mammal’s prey among eight prey types for use in trophic modelling andrelated food web studies. However, we reconsidered the prey composition of baleen whales, because theyused different prey species in each region. As to the categories of prey species, we divided them into threegroups such as fish (pelagic and mesopelagic), cephalopods (squids) and crustaceans (copepods,
amphipods and krill).
Catch of marine organisms by fisheries in the worlds
For the comparison of amount of prey consumption by cetaceans with the amount of catch by fisheries in
the world, we used the annual catch statistics of marine organisms capture by commercial fisheries by the
Food of Agriculture Organization of the United Nations (FAO).
FAO divides the seas of the world into major fishing areas for statistical purposes (Fig. 1). We grouped
these statistical areas into three ocean regions. They are the Southern Hemisphere including the Indian
Ocean (FAO areas 41 (Southwest Atlantic), 47 (Southeast Atlantic), 51 (Western Indian Ocean), 57(Eastern Indian Ocean), 81 (Southwest Pacific), 87 (Southeast Pacific), and 48. 58. 88 (Southern Oceans)),
the North Pacific (61 (Northwest Pacific), 67 (Northeast Pacific), 71 (Western Central Pacific) and 77(Eastern Central Pacific)) and the North Atlantic (21 (Northwest Atlantic), 27 (Northeast Atlantic), 31(Western Central Atlantic), 34 (Eastern Central Atlantic) and 37 (Mediterranean and Black Sea)). The
amounts of fisheries catch statistics excluding inland fisheries and Aquaculture in 1996 was used fromFAO (1998). For the sake of convenience we name these three ocean regions SHIO, NP and NA,
respectively.
We summed up the catch species in 1996 into four groups (fish, cephalopods, crustaceans and others)
based on FAO Fishery statistics (FAO, 1998). Among them a group of others which include seaweed andothers is not a prey organisms of cetaceans, so that this group is excluded from the analysis. Table 2
shows the results.

RESULTSSouthern Hemisphere including Indian Ocean
Estimated biomass of cetaceans
The biomass of fin, minke and sperm whales accounted respectively for 24.7%, 26.1% and 29.4% of
total biomass of cetaceans (19,147 thousand tons) calculated in this study (Table 3-1).
Estimated daily prey consumption of cetaceans based on three methods
Estimated daily prey consumption of each cetacean species is given in Table 4-1.
Estimated daily rate of prey intake per body weight from equation (1) ranges from 0.93% in the case of
the blue whale of which average body weight is 102,737kg (i.e. 957kg of prey weight per day) to 13.99%
in a 28kg in Commerson’s dolphin (i.e. 4kg prey per day).
Estimates of the rate of prey intake per body weight per day from equation (2) range from 1.52% in theblue whale (i.e. 1,560kg prey per day) to 7.70% in Commerson’s dolphin (i.e. 2kg prey per day).
When we apply the Method-3, the blue whale takes 3,596 kg of prey (3.5%) per day and theCommerson’s dolphin takes 1 kg of prey (3.5%) per day.
Estimated annual prey consumption of cetaceans based on three methods
Estimated annual prey consumption of cetaceans is given in Table 5-1.

10

We calculated the annual prey consumption by baleen and toothed whales to be 77-159 and 45-85
million tons, respectively. Among them the annual prey consumption by minke and sperm whales
accounted for 40-55% of total annual prey consumption by baleen whales and 67-84% of total annual
prey consumption by toothed whales, respectively.
According to the assumed prey composition as shown in Table 6-1, 76-155 million tons of crustaceans(mainly Euphausia superba) were consumed by baleen whales. Cephalopods (mainly squids) wereconsumed by only toothed whales and amounted to 27-56 million tons. The annual crustacean
consumption by minke whales accounted for 42-58% of total annual crustacean consumption by baleen
whales. And the annual cephalopod consumption by sperm whales accounted for 76-90% of total annual
cephalopod consumption by cetaceans (Table 7-1).
Competition between commercial fisheries and cetaceans
Total fish consumption by cetaceans was 18-32 million tons, accounting for 66-120% of commercial
fisheries fish catch (27 million tons) in 1996. Total cephalopod consumption by cetaceans was 27-56
million tons, it was one order of magnitude greater than the commercial fisheries cephalopods catch (onemillion tons) in 1996.
North PacificEstimated biomass of cetaceans
The biomass of fin and sperm whales accounted respectively for 13.5% and 34.9% of total biomass bycetaceans (6,646 thousand tons) (Table 3-2).
Estimated daily prey consumption of cetaceans based on three methods
Estimated daily prey consumption of each cetacean species is given in Table 4-2.
Estimated daily rate of prey intake per body weight from equation (1) ranges from 0.93% in the case of
the blue whale of which average body weight is 102,737kg (i.e. 957kg of prey weight per day) to 15.14%
in a 22kg in vaquita (i.e. 3kg prey per day).
Estimates of the rate of prey intake per body weight per day from equation (3) range from 1.30% in theblue whale (i.e. 1,332kg prey per day) to 8.11% in vaquita (i.e. 2kg prey per day).
When we apply the Method-3, the blue whale takes 3,596 kg of prey (3.5%) per day and the vaquita
takes 1 kg of prey (3.5%) per day.
Estimated annual prey consumption of cetaceans based on three methods
Estimated annual prey consumption of cetaceans is given in Table 5-2.
The annual prey consumption by baleen and toothed whales was 16-39 million tons and 43-56 million
tons, respectively. Among them the annual prey consumption by fin, minke and sperm whales accounted
for 23-29%, 7-11% of total annual prey consumption by baleen whales and 25-64% of total annual prey
consump tion by toothed whales, respectively.
According to the estimated prey composition (Table 6-2), consumption by baleen whales feeding onfish and crustaceans (copepods and krill), amounted to 2-4 and 14-35 million tons, respectively. The
annual fish consumption by fin and minke whales accounted for 9-14%, 47-58% of total annual fishconsumption by baleen whales, respectively. Consumption by toothed whales mainly feeding on fish andcephalopods (squids), amounted to 17-28, 22-27 million tons, respectively. The annual fish consumption
by sperm whales and common dolphins accounted for 12-44%, 11-19% of total annual fish consumption
by toothed whales, respectively. The annual cephalopod consumption by sperm whales accounted for
36-75% of total annual cephalopod consumption by toothed whales (Table 7-2).

11

Competition between commercial fisheries and cetaceans
Total fish consumption by cetaceans was 21-30 million tons accounting for 66-96% of commercial
fisheries fish catch (31 million tons) in 1996. Total cephalopod consumption by cetaceans was 22-28
million tons, one order of magnitude greater than the commercial fisheries cephalopods catch (1.6 million
tons) in 1996.
North Atlantic
Estimated biomass of cetaceans
The biomass of fin, minke and sperm whales accounted respectively for 31.5%, 11.7% and 42.1% of total
biomass by cetaceans (8,356 thousand tons) (Table 3-2).
Estimated daily prey consumption of cetaceans based on three methods
Estimated daily prey consumption of each cetacean species is given in Table 4-3.
Estimated daily rate of prey intake per body weight from equation (1) ranges from 0.93% in the case of
the blue whale of which average body weight is 102,737kg (i.e. 957kg of prey weight per day) to 13.52%
in a 31kg in the harbour porpoise (i.e. 4kg prey per day).
Estimates of the rate of prey intake per body weight per day from equation (3) range from 1.30% in theblue whale (i.e. 1,332kg prey per day) to 7.53% in harbour porpoise (i.e. 2kg prey per day).
When we apply the Method-3, the blue whale takes 3,596 kg of prey (3.5%) per day and the harbour
porpoise takes 1 kg of prey (3.5%) per day.
Estimated annual prey consumption of cetaceans based on three methods
Estimated annual prey consumption of cetaceans is given in Table 5-3.
The annual prey consumption by baleen and toothed whales was 21-52 and 34-55 million tons,
respectively. Among them the annual prey consumption by fin, minke and sperm whales accounted for
51-65%, 24-38% of total annual prey consumption by baleen whales and 62-82% of total annual prey
consumption by toothed whales, respectively.
According to the estimated prey composition (Table 6-3), baleen whales feeding on fish andcrustaceans (copepods and krill), amounted to 6-11, 15-41 million tons, respectively. The annual fishconsumption by fin and minke whales accounted for 5-9%, 68-78% of total annual fish consumption bybaleen whales, respectively. Consumption by toothed whales mainly feeding on fish and cephalopods(squids), amounted to 14-24, 24-39 million tons, respectively. The annual fish consumption by sperm
whales and long-finned pilot whales accounted for 60-81%, 15-31% of total annual fish consumption by
toothed whales, respectively. The annual cephalopod consumption by sperm whales accounted for
62-82% of total annual cephalopod consumption by toothed whales (Table 7-3).
Competition between commercial fisheries and cetaceans
Total fish consumption by cetaceans was 15-25 million tons, accounting for 87-144% of commercial
fisheries fish catch (17 million tons) in 1996. Total cephalopod consumption by cetaceans was 24-39
million tons, this value was two orders of magnitude greater than the commercial fisheries cephalopod
catch (0.4 million tons) in 1996.

DISCUSSION
In this paper, we assessed again the annual prey consumption of cetaceans in the worlds based on newly
available and recent abundance estimates of cetaceans, new average body weight and three previous
methods to estimate daily prey consumption. As for the difference from the first assessment, new estimate12

is 30-60 million tons lesser for annual prey consumption by cetaceans in the world. This is due to theaverage weight of the sperm whales.
As mentioned above, information on the abundance of many species of cetaceans was not included in
our tables, because of the lack of data on abundance estimates for them. Furthermore, the research areasof them have not yet covered whole the range of their distribution.
The same figure of average body weight is used in this paper. However, the size compositions aredifferent by stocks, and there are sexual and age segregation in the distribution of some cetacean species.
These factors will be better to consider for further study on this problem. Therefore, the actual figures ofannual prey consumption by all cetaceans should be larger than the present results.
Because of the different types of assumptions in three methods used to estimate daily prey consumption,
the highest estimate was nearly twice of the lowest. However, the total annual prey consumption was
estimated to be 248-434 million tons in the world, and it is clear from the present study that cetaceans
feed on the range of hundreds of million tons of marine organisms.
We tried to assess the competition between cetaceans and commercial fisheries in each region as
follows:
Southern Hemisphere including Indian Ocean
The total fish consumption by cetaceans was 18-32 million tons that accounted for 67-119% of current
commercial fisheries catch of fish. Northridge (1984) reported the distribution, prey species of cetaceansin the Southern Hemisphere including Indian Ocean, and he stated that the population and prey species ofmost cetaceans were unknown. Most baleen whales (blue whale, fin whale, sei whale, minke whale andhumpback whale) feed mainly on krill (mainly Euphausia superba), and their feeding grounds are in the
Antarctic (Kawamura, 1980a; 1994).
Nemoto (1959) categorized that the feeding types of baleen whales in the Southern, as follows:
Euphausiid feeder: blue whale, fin whale, humpback whale and sei whale
Amphipod feeder: sei whale
Copepod feeder: right whale, sei whale
Fish feeder: Bryde’s whale
Minke whale is considered to be an euphausiid feeder (Horwood, 1990; Ichii and Kato, 1991; Tamura,1998). Northridge (1984) stated that these baleen whales excluding Bryde’s whale did not mainly feed onfish, and no interactions with fisheries were likely.
Bryde’s whale tends to stay in warmer waters. They are known to include some commercial fish as
prey species. Best (1967) reported that they consumed 47% fish and 53% euphausiids in South Africa.
Their fish are including some commercial fish such as pilchard (Sardinops ocellata), anchovy (Engraulis
capensis) and mackerels (Trachurus spp.). Best (1977) found that the inshore form of Bryde’s whale eat
mainly fish, especially pilchard (S. ocellata), anchovy (E. capensis) and horse mackerel (Trachurus
capensis). Kawamura (1980b) reported that they feed mainly on krill (e.g. Euphausia diomedeae, E.
recurva and Thysanoessa gregaria) in the South Pacific and Indian Ocean. Northridge (1984) stated that
this species would seem to have some amount of competition with fisheries, however, no conflict wasevident at present.
In almost all of small cetacean, their population sizes and prey species are unknown (Northridge, 1984).
However, their main prey species seemed to be the fish and squid distribute pelagic and mesopelagic.
Hence, there are some notorious information of interactions between fish fisheries and cetaceans such as
killer whale, false killer whale, and common dolphin in the region (Northridge, 1984).
As for sperm whale, their biomass is large (5,630 thousand tons), occupying 29.4% of total biomass ofcetaceans in the region. However, this value refers only to Antarctic, while sperm whales distribute alloceans from equatorial waters to the Polar Regions. Their prey species is dominated by mesopelagic13

squids, for which there is no commercial fishery. However, they eat mainly fish in such region as New
Zealand (Kawakami, 1980). Even though the share of commercial fish is small in their prey consumption,
the absolute quantity of fish consumption is very large because of their huge biomass. There may be someinteractions between sperm whales and fish fisheries. Furthermore, if the commercial fisheries of squid or
bottom fish and/or the abundance of sperm whales expand in the future, there may be some interactions
between sperm whales and squid or bottom fish fisheries.
In the Antarctic, baleen whales excluding Bryde’s whales feed mainly on krill during austral summer,
where the krill fisheries decreased recently because of diminishing of market. Of these species ofcetaceans, the minke whales play an important role in the prey web in the Antarctic in particular.
Armstrong and Siegfried (1991) indicated that the minke whales consume 95% of the total biomass ofkrill which is consumed by baleen whales in the Antarctic. This study showed that the annual crustacean
consumption by minke whales was 40-60 million tons, and the amount accounted for 40-54% of total
annual crustacean consumption by cetaceans in the Southern Hemisphere. Tamura et al. (1997) estimatedthe prey consumption of krill by minke whales around the Ross Sea in the Antarctic to be an order ofmagnitude greater than the estimated consumption by Adelie penguins and crabeater seals. We consideredthat there was direct competition for krill among cetaceans, seals and sea birds in austral summer in the
Antarctic. Krill fishery appears to be of minor importance now. However, any development of this fishery
can lead to increased competition between cetaceans and fisheries.
For better understanding of this phenomenon, it will be necessary to have more abundance estimate ofcetaceans, quantitative information of prey species to assess the interaction between fisheries andcetaceans. Especially as for Indian Ocean, there is no available abundance information of cetaceans at all.
North Pacific
The total fish consumption by cetaceans was 20-29 million tons accounting for 68-97% of commercial
fisheries fish catch in recent years.
In contrast to Southern Hemisphere, many species of baleen whales feed on various pelagic preyspecies of zooplankton, squid and fish (Kawamura, 1980a). Nemoto (1959) categorized that the feeding
types of baleen whales in the North Pacific, as follows:
Euphausiid feeder: blue whale, fin whale, Bryde’s whale, humpback whale and minke whale
Copepod feeder: right whale, sei whale and fin whale
Fish feeder: fin whale, Bryde’s whale, humpback whale and minke whale
Squid feeder: fin whale, sei whale
Northern right whales and bowhead whales feed on small copepods (e.g. Calanus glacialis and C.
hyperboreus) (Nemoto, 1959; Kawamura, 1980a). And, blue whales feed on krill (e.g. Euphausia pacifica,
Thysanoessa inermis and T. longipes) (Nemoto, 1959; Kawamura, 1980a).
Fin whales feed on many kinds of fish, mostly small schooling fish such as Japanese anchovy(Engraulis japonicus), Pacific saury (Cololabis saira), chub mackerel (Scomber japonicus), Pacificherring (Clupea pallasii) and walleye pollock (Theragra chalcogramma). And, they also eat a variety ofpelagic zooplankton and even some squid such as Japanese flying squid (Todarodes pacificus). Their preyspecies overlap with some commercial catch and their biomass is larger than other baleen whales, so there
may be interactions to some extent in the North Pacific.
Humpback whale also feed on many kinds of fish, mostly small schooling fish such as capelin(Mallotus villosus), chum salmon (Oncorhynchus keta), sand lance (Ammodites hexapterus, A.
personatus), Pacific herring (Clupea harengus) and walleye pollock, as well as a variety of pelagic krill(e.g. Euphausia pacifica) (Nemoto, 1959; Kawamura, 1980a). Northridge (1984) stated that nointeractions with fisheries were apparent. However, their prey species also overlap with some commercial
catch, and thus there may be interactions to some extent in the North Pacific.

14

On the other hand, sei whales feed on copepods (Calanus spp.), but they also feed on some small
schooling fish such as Japanese anchovy, Japanese pilchard (Sardinops melanostictus) and Japanese
flying squid. Bryde’s whales feed on krill, but they also feed on some small schooling fish such as
Japanese anchovy and Japanese pilchard (Nemoto, 1959; Kawamura, 1980a). At least, there is one reportof a Bryde’s whale that had been feeding upon penaeid shrimp in the South China Sea (Persons et al.
1999). Prey species of sei whales and Bryde’s whales also varied both geographically and temporally in
the North Pacific. Northridge (1984) stated that there appear to be no reported conflicts with fisheries.
However, their prey species overlap with some commercial fisheries catch, there may be an interaction tosome extent in the North Pacific.
As for minke whales, they feed on various pelagic prey species of zooplankton, squid and fish (Nemoto,
1959; Kawamura, 1980a; Tamura and Fujise, 2000a). Prey species varied both geographically andtemporally. For example, Kasamatsu and Tanaka (1992) reported that the composition of prey of minke
whales caught off the Sanriku-Hokkaido area changed largely during 1965-1987. They suggested thatchub mackerel was the dominant prey species in 1968-1976, but Japanese pilchard was then the dominant
prey species after 1977. Tamura et al. (1998) examined in detail on the stomach contents of minke whalescaught under the JARPN, and they noted that dominant prey species have changed to Pacific saury andJapanese anchovy in recent years. They feed on pelagic zooplankton and pelagic schooling fish. Tamura
and Fujise (2000a) reported most of the minke whale sightings occurred close to Pacific saury fishinggrounds. Tamura and Fujise (2000b) estimated seasonal consumption of Pacific saury by minke whales in
Pacific side of Japan during August and September; this value was equivalent to 10–21% of the catch ofPacific saury in Japan. Northridge (1984) stated that there was some interaction between this species andfisheries in the North Pacific. At least, we consider that there exists direct competition between minke
whales and commercial Pacific saury fisheries existed from summer to autumn in the western North
Pacific.
Gray whale feed mainly on benthic amphipods and shrimp. It is reported that their recent number isbeing estimated with 26,300 individuals and is increasing with 3.2% of year rate. Many stranding arebeing reported and the lack of prey resource is pointed out as major one of the factor. There may
demonstrate that the gray whales the eastern North Pacific stock are approaching their carrying capacity.
Wade and Gerrodette (1993) and Miyashita (1990, 1991, 1993a, b) estimated the population of small
cetaceans in the North Pacific. Their main prey species seemed to be fish and squids, which distributed
pelagic and mesopelagic. At least, there are some reports of interactions between fish fisheries andcetaceans such as killer whale, false killer whale, Dall’s porpoise and common dolphin in the region.
Abundance estimate of small cetaceans, quantitative data of prey species are necessary to assess theinteraction between fisheries and small cetaceans in the future.
As for sperm whale, their biomass is large (2,311 thousand tons), occupying 34.9% of total biomass ofcetaceans. Their prey species is dominated by mesopelagic squid, for which there seems to be nocommercial fish fishery. However, they eat some commercial pelagic fish such as sardines, salmon(Onchorhynchus gorbusha), Pacific saury, Chub mackerel in the western North Pacific (Kawakami, 1980).
Furthermore, Rice (1989) reported sperm whales fed on black cod, or sablefish, from longlines beingfrom retrieved by fisherman in the eastern Gulf of Alaska. Although their fish quantity is relatively small
consumption, it is conceivable that the whole quantity of fish consumption is very large, because theirbiomass is too large. There may be some interactions between sperm whale and fisheries. Furthermore, if
the commercial fisheries of squid or bottom fish and/or the abundance of sperm whales expand, there may
be some interactions between sperm whale and squid and/or bottom fish fisheries.
In the Bering Sea, Lowry and Frost (1985) tried to clearly the biological interactions between marine
mammals and commercial fisheries. They assessed the potential interactions between marine mammals
and fisheries in the Bering Sea. They calculated the ranked value based on diet composition, feeding15

strategy, importance, population size, and so on. However, there was no question that competition withfisheries occurred, because it were insufficient knowledge as to how marine mammals eat their prey(especially in relation to geographical, seasonal and yearly changes of prey species) and how the energy
got from feeding relates to growth, maturation, reproduction and survival.
Trites et al. (1997) tried the assessment of the degree of competition between fisheries and marine
mammals in the Pacific Ocean (FAO areas 61, 67, 71, 77, 81, 87 and 88). They calculated the total annual
prey consumption of marine mammals, as 150 million tons, equivalent to roughly three times thecommercial fis heries catch. However, their prey consisted of mesopelagic squids and fish, they proposedthat the most important consumers of fish and competitor of commercial fisheries were probably otherpredator fish, not marine mammals. But, they considered that there was an indirect competition between
fisheries and cetaceans in the Pacific Ocean. Furthermore, the available primary production for sustaining
fish and marine mammals being reduced, they suggested that the commercial fisheries could not continue
to expand as previously.
According to the North Pacific Marine Science Organization (PICES), there still exists drastic shortageof quantitative data on feeding ecology of top predators. In 2000, a workshop on “ A review of thetechnical basis for estimating the abundance of marine birds and mammals, and the impact of theirpredation on other organisms ” will be held in Japan. It is expected that improvement of knowledge on
prey consumption of marine mammals and their potential for top-down impacts in marine ecosystem in
the North Pacific will be furthered.
North Atlantic
The total fish consumption by cetaceans was 15-25 million tons accounting for 87-144% of commercial
fisheries fish catch in recent years.
In contrast to Southern Hemisphere, many species of baleen whales feed on various pelagic preyspecies of zooplankton and fish similar to those in North Pacific (Kawamura, 1980a).
Northern right whales and bowhead whales feed on small copepods (e.g. Calanus glacialis and C.
hyperboreus). And, blue whales feed on krill (e.g. Meganyctiphanes norvegica, Thysanoessa inermis).
Northridge (1984) stated that these species did not feed on fish, and was unlikely to be affected bycommercial fisheries.
On the other hand, fin whales consumed various pelagic prey species of zooplankton, squid and fish.
They feed on many kinds of fish, such as capelin (Mallotus villosus), sand lance, mackerel, herring, cod,and lantern fish (Nemoto, 1959; Kawamura, 1980a). Prey species of fin whales varied both
geographically and temporally in the North Atlantic. Perkins and Beamish (1979) reported that the fin
whale feed mainly on capelin in Newfoundland. Northridge (1984) stated that there were no interactions
with fisheries. However, there was the possibility of interactions with fisheries, because their biomass waslarger than other baleen whales.
Sei whales feed on copepods (Calanus spp.), but they also feed on some small schooling fish andsquids in other regions. Bryde’s whales feed mainly on krill, but they also feed on some small schoolingfish in the North Pacific and Southern Hemisphere (Nemoto, 1959; Best, 1967, 1977; Kawamura,
1980a,b). Northridge (1984) stated that there appears to be no reported conflicts with fisheries. However,they consume some small schooling fish in other regions, there may be the possibility of the interaction
with fisheries.
Humpback whales feed on many species of fish, mostly small schooling fish such as capelin, as well as
a variety of pelagic krill (e.g. M. norvegica, T. inermis). Perkins and Beamish (1979) reported that the
humpback whale feed mainly on capelin in Newfoundland. Northridge (1984) stated that no interactions
with fisheries are apparent. However, as their prey species overlap with some commercial catch, so there
may be an interaction to some extent in the North Atlantic.

16

As for Minke whales, they eat various pelagic prey species of zooplankton and fish. Prey species ofminke whales varied both geographically and temporally. In this region, feeding ecology of minke whales
has already been studied, their diet varies according to season, geographical area and prey availability.
Although krill (e.g. M. norvegica, T. inermis) are the important prey species, a wide range of fish species,
among which capelin, herring and sand lance are predominant prey species. In the North Sea, mackerel(Scomber scombrus) and sand lance are thought to be the dominant prey species. In the Northeast Atlantic
and in the Barents Sea, a variety of prey is consumed, and the most important of which are krill, capelin
and herring, but gadoids, especially cod (Gadus morhua), saithe (Pollachius virens) and haddock(Melanogrammus aeglefinus), are also significant prey items (Haug et al. 1995; 1996). In recent years,
increased attention has been paid to interactions between commercial fisheries and minke whales in the
North Atlantic. For example, consumption of Atlantic herring by minke whales was estimated to be
633,000 tons per year in a part of the Northeast Atlantic. This is more than half of the total Norwegiancatch of herring (Folkow et al., 1997). Furthermore, Schweder et al. (2000) described that the net loss tothe herring and cod fishery is some five tones of herring and cod due to direct and indirect effect on thecatches of an extra minke whale in the Barents Sea using simulation model. There seems to be evidence
enough that there is direct competition between minke whales and commercial fisheries in the North
Atlantic.
The population and prey species of almost all small cetacean are unknown (Northridge, 1984). Theirmain prey species seems to be fish and squids, which distribute pelagic and mesopelagic. However, assame as North Pacific Ocean, there are some interactions between fish fisheries and cetaceans such as
killer whale, false killer whale, harbour porpoise, bottlenose dolphin, white beaked dolphin, white whaleand common dolphin in the region. We need to have more abundance estimate of small cetaceans
available, as well as quantitative data of prey species to assess the interaction between fisheries and small
cetaceans in the future.
As for sperm whale, their biomass is large (3,519 thousand tons), occupying 42.9% of total biomass ofcetaceans similar to other regions. Their prey species is dominated by mesopelagic squid, for which there
is no commercial fishery, however, it has been reported that they eat mainly fish in Iceland (Sigurjónsson
and Víkingsson, 1998). There may be some interactions between sperm whales and fish fisheries.
Furthermore, if the commercial fisheries of squid or bottom fish and/or the population of sperm whales
will expand, there will be some interactions between sperm whales and squid or bottom fish fisheries.
In the Barents Sea, Bogstad et al. (1997) studied the effect on stocks of cod, herring and capelin byremoving the stock of minke whale in a simulation study using the MULTSPEC model. They noted thatthe increasing harp seal (Phoca groenlandica) stock would most heavily affect the capelin and cod stock.
Furthermore, Schweder et al. (2000) describe that the net loss to herring and cod fisheries is some fivetones of herring and cod due to direct and indirect effect on the catches of an extra minke whale using
simulation model in the Barents Sea.
We again tried the assessment of daily and annual prey consumption of marine cetaceans based on
newly available and recent abundance estimates, new average body weight of each species and threemethods used previously. Furthermore, we estimated the annual prey consumption of cetaceans by prey
categories using assumed composition ratios, and considered the competition between cetaceans andfisheries at present for three regions (SHIO, NP and NA). There seems to be evidence enough that there isdirect competition between some cetaceans and commercial fisheries in the North Pacific and North
Atlantic. However, it will be necessary to have more available abundance estimate of cetaceans,quantitative information of prey species to assess the interaction between fisheries and cetaceans. The
meeting of Competition between Fisheries and Cetaceans will be held and organized along the lines ofprevious IWC-sponsored conferences, with an open symposium and an invitational workshop in 2001. In

17this meeting, we will have more detail knowledge of available abundance estimate of cetaceans,quantitative information of prey species. Furthermore, we will understand the potential of cetaceanshaving a impact on commercial fisheries, either directly (by consuming commercial species such as
herring, Pacific saury and anchovy), or indirectly (by competing for prey resources) using simulation
model in the Antarctic, Barents Sea, and so on.
Growing concerns about the possible consequences of competition between marine mammals andfisheries make this an increasingly important issue in fisheries management and conservation in the future.
For this purpose, comparative research on the seasonal, local and annual distribution and abundance of
cetaceans and their prey should be enlarged. It makes possible to develop a blanket multi-species
management of marine organisms involving marine mammals as whales, dolphins, porpoises andpinnipeds in order to allow a more realistic fisheries management strategy, long-term and/or short-termsustainability of marine organisms involving marine mammals and their conservation in the world.

ACKNOWLEDGMENT
Our sincere thanks are given to Dr. Hiroshi Hatanaka of the National Research Institute of Fisheries
Science (NRIFS), Dr. Hidehiro Kato and Mr. Tomio Miyashita of the National Research Institute of Far
Seas Fisheries (NRIFSF) and Drs. Yoshihiro Fujise and Gabriel Gó mez Díaz of the Institute of Cetacean
Research (ICR) for their valuable suggestions and useful comments on this paper. We would like toexpress our thanks also to Prof. Doug Butterworth of the University of Cape Town, for his helpful advice
on this paper.

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22

Table 1. Assessments of abundance in each area
1-1. Southern Hemisphere including Indian Ocean
SpeciesBlue whale
Pigmy blue whale

AreaoSouth of 30 So

Fin whale
Sei whale
Bryde's whale
Minke whale

South of 30 SoSouth of 30 S

Humpback whale
Southern right whale
Pygmy right whale
Baleen whales total

South of 30 S

Sperm whale
Pygmy sperm whale
Dwarf sperm whale

South of 30 S

Arnoux's beaked whale
Southern bottlenose whale*3
Beaked whales
Cuvier's beaked whaleoSouth of 60 SooAbundance

CV

1,255
5,000

0.36N.e.

85,200*1
10,86089,000761,000

N.e.
N.e.
N.e.
0.14-0.28

10,000
7,000
N.d.

0.27
N.e.
N.e.

209,000
N.d.
N.d.

*2

N.e.
N.e.
0.15
N.e.

Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale

N.d.
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

Hector's beaked whale
Pygmy beaked whale
True's beaked whale
Strap-toothed whale

N.d.
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin
Killer whale

N.d.
N.d.
N.d.
*4
58,500

N.e.
N.e.
N.e.
0.30

Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale

South of 50 SoSouth of 60 SoSouth of 60 S

*586,500
N.d.
N.d.
N.d.

0.80-1.04
N.e.
N.e.
N.e.

N.d.
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

N.d.
144,000
N.d.
N.d.

N.e.
0.17
N.e.
N.e.

Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin

N.d.
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

Clymene dolphin
Striped dolphin*6Common dolphin
Fraser's dolphin

N.d.
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

N.d.
3,211
N.d.

N.e.
N.e.
N.e.

3,408
N.d.
N.d.
N.d.

N.e.
N.e.
N.e.
N.e.

N.d.

N.e.

Melon-headed whale
TucuxiIndo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin
Hourglass dolphin
Peale's dolphin
Risso's dolphin

Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin
Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoiseoSouth of 50 S

the Magellan strait
New ZealandFinless porpoise
Toothed whales total
Cetaceans total*1: Estimates of abundance ranged from 9,720 to 12,000.
*2: Estimates of abundance ranged from 128,000 to 290,000.
*3: Arnoux's beaked whale + Southern bottlenose whale*4: Estimates of abundance ranged from 53,000 to 64,000.
*5: Estimates of abundance ranged from 43,000 to 130,000.
*6: Including long-beaked common dolphin

23

Source of abundance
IWC 1996; Perry et al. 1999
Gambell 1976; Perry et al. 1999
IWC 1979; Perry et al . 1999
IWC 1980; Mizroch et al . 1984; Braham 1991; Perry et al . 1999

510,000 5,900 -Ohsumi 1981
1,140,000 IWC 1991a
16,800 IWC in press
IWC in press; Perry et al . 1999

Butterworth et al. 1994; IWC 1995

0.44-0.46
N.e.
N.e.

N.d.
N.d.
599,000
N.d.

o

95% CI

450,000 -800,000 Kasamatsu and Joyce 1995

Butterworth et al. 1994; IWC 1995
Butterworth et al. 1994; IWC 1995

100,000 -200,000 Kasamatsu and Joyce 1995

Letherwood et al. 1988
Dawson and Stoolen 1988

1-2. North Pacific
SpeciesArea

Blue whale
Fin whale
Sei whale
Bryde's whale

Western PacificEastern tropical PacificSea of Japan

Minke whale

Okhotsk Sea-West Pacific
Humpback whale
Northern right whale
Bowhead whale
Gray whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Baird's beaked whale

Cuvier's beaked whale

Abundance

CV

3,300
*1
16,125

0.24N.e.

9,110
21,901
13,023
7,600

N.e.
0.19
0.20
0.40
0.30
N.e.
N.e.

95% CI

Source of abundance
Wade and Gerrodette 1993; Perry et al . 1999
Braham 1991; Perry et al . 1999
Tillman 1977; Perry et al . 1999

14,781 -32,450 Shimada and Miyashita 1997; IWC 1997b
Wade and Gerrodette 1993
IWC 1984

12,800 -48,600 IWC 1992b
Calambokidis et al . 1997; Perry et al . 1999
IWC 1998; Perry et al . 1999
2,108 IWC 1998; Perry et al . 1999

Eastern

25,000
*2
7,000
*3
300

Okhotsk Sea
Bering-Chukchi-Beaufort Seas
Eastern

900
7,500
26,3000.03

Western PacificEastern tropical Pacific

0.16
0.22
N.e.
0.29

Kato and Miyashita 1998
Wade and Gerrodette 1993

Eastern tropical Pacific102,112
22,666
N.D.
11,215Western PacificSea of Japan
Okhotsk Sea
Eastern tropical Pacific

3,950
1,260
660
20,000

0.28
0.45
0.27
0.27

Miyashita 1990
Miyashita 1990
Miyashita 1990
Wade and Gerrodette 1993

N.D.
N.D.
N.D.
N.D.

N.e.
N.e.
N.e.
N.e.

Blainville's beaked whale
Ginkgo-toothed beaked whale
Hubbs' beaked whale
Stejneger's beaked whale

404 6,400 21,900 -

9,200 Raftery and Zeh 1991; IWC 1992a
32,400 Hobbs and Rugh 1999; IWC in press

Wade and Gerrodette 1993

Killer whale
Short-finned pilot whale
False killer whale

Eastern tropical PacificWestern PacificWestern PacificEastern tropical Pacific8,500
53,608
16,66839,800

0.37
0.22
0.26
0.64

Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin
Rough-toothed dolphin

Eastern tropical PacificEastern tropical PacificEastern tropical Pacific38,90045,400N.D.
145,900

0.31
0.47
N.e.
0.32

Western PacificEastern tropical Pacific

988,000
83,289289,300

0.17-1.50
0.18
0.34

164,000 58,764 -

6,790,000 Miyashita 1993b
118,049 Miyashita 1993a
Wade and Gerrodette 1993

Western PacificEastern tropical PacificWestern PacificNortheastern

168,791
243,500
438,064
730,900

0.26
0.29
0.17
0.14

102,000 -279,044 Miyashita 1993a
Wade and Gerrodette 1993
614,503 Miyashita 1993a
Wade and Gerrodette 1993

Western / southern
CoastalEasternwhitebelly

1,298,400
29,800631,800
1,019,300

0.15
0.35
0.24
0.19

Western PacificEastern tropical PacificNorthern
Central570,038
1,918,000
476,300
406,100

0.18
0.11
0.37
0.38

Southern
Eastern tropical Pacific2,210,900
289,300
308,000
1,186,000

0.22
0.34
0.31-1.13
0.09
N.e.
N.e.

Seto Inland Sea

554,000
N.D.
N.D.
5,000

AlaskaUSSR

5,800
27,000

Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin

Spinner dolphin
Striped dolphin*4Common dolphin

Fraser's dolphin
Northern right whale dolphin
Dall's porpoise

Pacific
OkhotskHarbour porpoise
VaquitaFinless porpoiseWhite whale

34,723 10,034 -Wade and Gerrodette 1993
82,756 Miyashita 1993a
27,689 Miyashita 1993a
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993

312,285 -Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
397,435 -59,000 991,000 -

817,602 Miyashita 1993a
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
Wade and Gerrodette 1993
1,680,000 Miyashita 1993b
1,420,000 Buckland et al. 1993
Miyashita 1991, IWC 1993

Kasuya and Kureha 1979
IWC 1992c
IWC 1992c

Toothed whales total
Cetaceans total*1: Estimates of abundance ranged from 14,620 to 18,630.
*2: Estimates of abundance ranged from 6,000 to 8,000.
*3: Estimates of abundance ranged from 100 to 500.
*4: Including long-beaked common dolphin

241-3. North Atlantic
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale

Area
North Western Atlantic

North Eastern Atlantic
Central Atlantic

*1

CV

330
47,300

N.e.

4,000
N.D.
118,299
28,000

N.e.
N.e.

3,266
10,600
*2
400
450

0.07
N.e.
N.e.

190,000
N.D.
N.D.

N.e.
N.e.
N.e.

N.D.
44,300
N.D.
N.D.

N.e.
N.e.
N.e.
N.e.

N.D.
N.D.
5,500
778,000

N.e.
N.e.
N.e.
0.30

Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale

N.D.
N.D.
N.D.
N.D.

N.e.
N.e.
N.e.
N.e.

Atlantic hump-backed dolphin
Rough-toothed dolphin
White beaked dolphin
Atlantic white sided dolphin

N.D.
N.D.
13,42038,680

N.e.
N.e.
N.e.
N.e.

Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin

N.D.
N.D.
N.D.
N.D.

N.e.
N.e.
N.e.
N.e.

Spinner dolphin
Clymene dolphin
Striped dolphin*3Common dolphin

N.D.
N.D.
N.D.
N.D.

N.e.
N.e.
N.e.
N.e.

Iceland
CanadaUSSR

N.D.
28,51045,700
9,500

N.e.
N.e.

Canada-Greenland
Northern Hudson Bay

28,0001,300

Humpback whale
Northern right whale
Bowhead whale

West GreenlandWest of Iceland
North Western Atlantic

Abundance

Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale

Iceland

Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale

Fraser's dolphin
Harbour porpoiseWhite whale
NarwhalIcelandEastern

Iceland
Iceland

95% CI

Source of abundance

27,723 -Braham 1991; Perry et al . 1999
82,031 IWC 1992dBraham 1991; Perry et al . 1999

96,681 21,600 -

144,750 IWC 1997a
31,400 IWC 1991b

1,790 9,300 -

5,950 IWC 1991b
12,100 Smith et al . 1999
IWC 1986a; Perry et al. 1999
Zeh et al . 1993
Rice, 1989; Odell, 1992

Sigurjónsson and Víkingsson 1998

440,000 -Sigurjónsson and Víkingsson 1998
1,370,000 Buckland et al. 1992; IWC 1993

Sigurjónsson and Víkingsson 1998
Sigurjónsson and Víkingsson 1998

Sigurjónsson and Víkingsson 1998
IWC 1992c
IWC 1992c
22,000 -Toothed whales total
Cetaceans total*1: Estimates of abundance ranged from 100 to 560.
*2: Estimates of abundance ranged from 300 to 500.
*3: Including long-beaked common dolphin

25

33,500 IWC 1992c
IWC 1992c

Table 2. Catch of each group by commercial fisheries in 1996 (FAO 1998).
Study Region

FAO area
Fish

Southern
Hemisphere(including
Indian Ocean)North PacificNorth Atlantic

Total

41
47
51
57
81
87
48,58,88
Total
61
67
71
77
Total
21
27
31
34
37
Total

Commercial Fisheries Catch in 1996 (tons)
Cephalopoda Crustacean
OthersTotal

1,667,613
1,012,052
3,602,001
3,423,452
550,967
16,761,837
9,963
27,027,885
19,716,050
2,750,809
7,505,751
1,240,702
31,213,312
1,013,674
10,467,611
1,275,317
3,112,271
1,277,218
17,146,091

716,652
7,996
94,36784,65673,55451,70528
1,028,958
1,156,571
627
282,374
188,331
1,627,903
38,88058,43531,143
192,083
60,480381,02181,745
10,933
323,099
267,892
7,203
63,651
101,212855,735
2,329,317
98,640675,117
89,941
3,193,015
392,028
261,751
257,865
49,84345,193
1,006,680

8,061
735
11,336
81,473
6,395
150,918
0
258,918
1,764,243
30,454375,276
49,702
2,219,675
586,150
240,684
132,3428,970
111,126
1,079,272

2,474,071
1,031,716
4,030,803
3,857,473
638,119
17,028,111
111,203
29,171,496
24,966,181
2,880,530
8,838,518
1,568,676
38,253,905
2,030,732
11,028,481
1,696,667
3,363,167
1,494,017
19,613,064

75,387,288

3,037,882

5,055,430

3,557,865

87,038,465

26

Table 3. Estimated the annual prey consumption based on three methods.
3-1. Southern Hemisphere including Indian Ocean
SpeciesBlue whale
Pigmy blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Southern right whale
Pygmy right whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Arnoux's beaked whale
Southern bottlenose whale*2
Beaked whales
Cuvier's beaked whale
Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale
Hector's beaked whale
Pygmy beaked whale
True's beaked whale
Strap-toothed whale
Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
TucuxiIndo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin
Hourglass dolphin
Peale's dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin*3Common dolphin
Fraser's dolphin
Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin
Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoise
Finless porpoise
Toothed whales total
Cetaceans total

Average body Abundance
weight (kg)(inds.)
102,737
102,737
55,59016,811
16,1436,566
30,40823,383N.d.
*126,939
177
101
1,733
1,079
1,406
829
N.D.
449
501
376
294
N.D.
445
631
334
1,069
87
2,281
851
643
578
98
105
39
115
92
50
34
59
224
188
65
66
41
47
116
80
95
62
28
33
67
31
58
42
41

*1: Only average weight of male (26,939kg)*2: Arnoux's beaked whale + Southern bottlenose whale*3: Including long-beaked common dolphin

27

1,255
5,000
85,20010,86089,000761,000
10,0007,000
N.d.
209,000
N.d.
N.d.
N.d.
N.d.
599,000
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
58,50086,500
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
144,000
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
3,211
N.d.
3,408
N.d.
N.d.
N.d.
N.d.

Biomass(t)

Biomass%

128,935
513,685
4,736,268
182,567
1,436,727
4,996,726
304,080
163,681

0.7
2.7
24.7
1.0
7.5
26.1
1.6
0.9

12,462,669
5,630,251

65.1
29.4

842,194

4.4

133,439
73,612

0.7
0.4

4,896

0.0

90

0.0

228

0.0

6,684,709
19,147,379

34.9
100.0

3-2. North Pacific
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Gray whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Baird's beaked whale
Cuvier's beaked whale
Blainville's beaked whale
Ginkgo-toothed beaked whale
Hubbs' beaked whale
Stejneger's beaked whale
Killer whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin
Rough-toothed dolphin
Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Spinner dolphin
Striped dolphin*1Common dolphin
Fraser's dolphin
Northern right whale dolphin
Dall's porpoise
Harbour porpoise
VaquitaFinless porpoiseWhite whale
Toothed whales total
Cetaceans total

Average body Abundance
weight (kg)(inds.)
102,737
55,59016,811
16,1436,566
30,40823,38331,076
15,372

3,300
16,125
9,110
34,92432,600
7,000
1,200
7,500
26,30018,519
177
101
3,137
829
449
376
470
455
2,281
643
578
98
105
115
92
78
224
188
65
41
116
80
95
105
61
31
22
41
313

124,778
N.D.
11,2155,870
20,000
N.D.
N.D.
N.D.
N.D.
8,500
53,60856,46838,90045,400N.D.
145,900
988,000
372,589412,291
2,497,164
1,651,100
2,488,038
2,664,300
289,300
308,000
1,740,000
N.D.
N.D.
5,000
32,800*1: Including long-beaked common dolphin

28

Biomass(t)

Biomass%

339,032
896,389
153,148563,778
214,052
212,856
28,060233,070
404,284
3,044,668
2,310,764

5.1
13.5
2.3
8.5
3.2
3.2
0.4
3.5
6.1
46.0
34.9

1,133
18,414
16,580

0.0
0.3
0.3

19,38934,47032,639
3,812
4,767

0.3
0.5
0.5
0.1
0.1

13,42377,064
83,46077,511
162,316
67,695
288,612213,144
27,48432,340106,140

0.2
1.2
1.3
1.2
2.5
1.0
4.4
3.2
0.4
0.5
1.6

205
10,2663,601,626
6,646,294

0.0
0.2
54.4
100.4

3-3. North Atlantic
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale
Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Atlantic hump-backed dolphin
Rough-toothed dolphin
White beaked dolphin
Atlantic white sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin
Common dolphin*1
Fraser's dolphin
Harbour porpoiseWhite whale
NarwhalToothed whales total
Cetaceans total

Average body Abundance
weight (kg)(inds.)
102,737
55,59016,811
16,1436,566
30,40823,38331,076330
47,3004,000
N.D.
149,000
10,600400
45018,519
177
101
829
1,689
449
455
393
445
2,281
851
643
578
98
105
77
92
142
92
224
188
65
66
41
47
116
80
95
31
313
325

190,000
N.D.
N.D.
N.D.
44,300
N.D.
N.D.
N.D.
N.D.
5,500
778,000
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
13,42038,680
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
28,51055,20029,300*1: Including long-beaked common dolphin

29

Biomass(t)

Biomass%

33,9032,629,407
67,244

0.4
31.5
0.8

978,334
322,325
9,353
13,984
4,054,550
3,518,610

11.7
3.9
0.1
0.2
48.5
42.1

74,8230.9

12,546
662,078

0.2
7.9

1,906
3,559

0.0
0.0

884
17,2789,523
4,301,204
8,355,755

0.0
0.2
0.1
51.5
100.0

Table 4. Estimated the daily prey consumption based on three methods.
4-1. Southern Hemisphere including Indian Ocean
Species
Baleen whales
Blue whale
Pigmy blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Southern right whale
Pygmy right whale
Toothed whales
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Arnoux's beaked whale
Southern bottlenose whale*2
Beaked whales
Cuvier's beaked whale
Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale
Hector's beaked whale
Pygmy beaked whale
True's beaked whale
Strap-toothed whale
Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
TucuxiIndo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin
Hourglass dolphin
Peale's dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin*3Common dolphin
Fraser's dolphin
Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin
Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoise
Finless porpoise

Average bodyweight (kg)Method-1(kg)%

Method-2(kg)%

Method-3(kg)%

102,737
102,737
55,59016,811
16,1436,566
30,40823,383
N.d.

957
957
634
285
277
152
423
355

0.93
0.93
1.14
1.69
1.72
2.31
1.39
1.52

1,560
1,560
964
378
366
181
601
490

1.52
1.52
1.73
2.25
2.27
2.76
1.98
2.09

3,596
3,596
1,946
588
565
230
1,064
818

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

390
13
9
62
45
54
38

1.45
7.61
9.16
3.58
4.19
3.84
4.57

467
9
6
55
38
46
31

1.73
5.16
5.83
3.15
3.49
3.29
3.69

943
6
4
61
38
49
29

3.50
3.50
3.50
3.50
3.50
3.50
3.50

25
27
22
19

5.60
5.40
5.94
6.44

19
21
16
14

4.22
4.12
4.38
4.62

16
18
13
10

3.50
3.50
3.50
3.50

25
32
21
45
8
75
39
32
30
9
9
5
10
9
6
4
6
16
14
7
7
5
6
10
8
9
7
4
4
7
4
6
5
5

5.61
5.00
6.17
4.20
9.62
3.27
4.53
4.97
5.15
9.25
9.04
12.54
8.77
9.44
11.55
13.12
10.94
7.04
7.46
10.59
10.54
12.33
11.79
8.75
9.89
9.35
10.76
13.99
13.25
10.49
13.52
11.00
12.21
12.33

19
25
15
37
5
68
31
25
23
6
6
3
7
5
3
3
4
11
10
4
4
3
3
7
5
6
4
2
2
4
2
4
3
3

4.22
3.92
4.50
3.49
6.02
2.96
3.67
3.90
3.99
5.87
5.78
7.16
5.67
5.95
6.79
7.38
6.55
4.90
5.09
6.41
6.39
7.09
6.88
5.66
6.13
5.91
6.48
7.70
7.43
6.37
7.53
6.57
7.04
7.09

16
22
12
37
3
80
30
23
20
3
4
1
4
3
2
1
2
8
7
2
2
1
2
4
3
3
2
1
1
2
1
2
1
1

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

*1

26,939
177
101
1,733
1,079
1,406
829
N.D.
449
501
376
294
N.D.
445
631
334
1,069
87
2,281
851
643
578
98
105
39
115
92
50
34
59
224
188
65
66
41
47
116
80
95
62
28
33
67
31
58
42
41

*1: Only average weight of male (26,939kg)*2: Arnoux's beaked whale + Southern bottlenose whale*3: Including long-beaked common dolphin304-2. North Pacific
Species
Baleen whales
Blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Gray whale
Toothed whales
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Baird's beaked whale
Cuvier's beaked whale
Blainville's beaked whale
Ginkgo-toothed beaked whale
Hubbs' beaked whale
Stejneger's beaked whale
Killer whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin
Rough-toothed dolphin
Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Spinner dolphin
Striped dolphin*1Common dolphin
Fraser's dolphin
Northern right whale dolphin
Dall's porpoise
Harbour porpoise
VaquitaFinless porpoiseWhite whale

Average bodyweight (kg)Method-1(kg)%

Method-2(kg)%

Method-3(kg)%

102,737
55,59016,811
16,1436,566
30,40823,38331,076
15,372

957
634
285
277
152
423
355
430
268

0.93
1.14
1.69
1.72
2.31
1.39
1.52
1.38
1.74

1,332
824
323
313
155
514
418
522
301

1.30
1.48
1.92
1.94
2.36
1.69
1.79
1.68
1.96

3,596
1,946
588
565
230
1,064
818
1,088
538

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

18,519
177
101
3,137
829
449
376
470
455
2,281
643
578
98
105
115
92
78
224
188
65
41
116
80
95
105
61
31
22
41
313

304
13
9
92
38
25
22
26
25
75
32
30
9
9
10
9
8
16
14
7
5
10
8
9
9
7
4
3
5
20

1.64
7.61
9.16
2.95
4.57
5.60
5.94
5.51
5.57
3.27
4.97
5.15
9.25
9.04
8.77
9.44
9.97
7.04
7.46
10.59
12.33
8.75
9.89
9.35
9.04
10.82
13.52
15.14
12.33
6.31

348
9
6
87
31
19
16
20
19
68
25
23
6
6
7
5
5
11
10
4
3
7
5
6
6
4
2
2
3
14

1.88
5.16
5.83
2.77
3.69
4.22
4.38
4.17
4.20
2.96
3.90
3.99
5.87
5.78
5.67
5.95
6.16
4.90
5.09
6.41
7.09
5.66
6.13
5.91
5.78
6.50
7.53
8.11
7.09
4.56

648
6
4
110
29
16
13
16
16
80
23
20
3
4
4
3
3
8
7
2
1
4
3
3
4
2
1
1
1
11

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

*1: Including long-beaked common dolphin314-3. North Atlantic
Species
Baleen whales
Blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Toothed whales
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale
Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Atlantic hump-backed dolphin
Rough-toothed dolphin
White beaked dolphin
Atlantic white sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin
Common dolphin*1
Fraser's dolphin
Harbour porpoiseWhite whale
Narwhal

Average bodyweight (kg)Method-1(kg)%

Method-2(kg)%

Method-3(kg)%

102,737
55,59016,811
16,1436,566
30,40823,38331,076

957
634
285
277
152
423
355
430

0.93
1.14
1.69
1.72
2.31
1.39
1.52
1.38

1,332
824
323
313
155
514
418
522

1.30
1.48
1.92
1.94
2.36
1.69
1.79
1.68

3,596
1,946
588
565
230
1,064
818
1,088

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

18,519
177
101
829
1,689
449
455
393
445
2,281
851
643
578
98
105
77
92
142
92
224
188
65
66
41
47
116
80
95
31
313
325

304
13
9
38
61
25
25
23
25
75
39
32
30
9
9
8
9
12
9
16
14
7
7
5
6
10
8
9
4
20
20

1.64
7.61
9.16
4.57
3.62
5.60
5.57
5.85
5.61
3.27
4.53
4.97
5.15
9.25
9.04
10.02
9.44
8.18
9.44
7.04
7.46
10.59
10.54
12.33
11.79
8.75
9.89
9.35
13.52
6.31
6.23

348
9
6
31
53
19
19
17
19
68
31
25
23
6
6
5
5
8
5
11
10
4
4
3
3
7
5
6
2
14
15

1.88
5.16
5.83
3.69
3.16
4.22
4.20
4.34
4.22
2.96
3.67
3.90
3.99
5.87
5.78
6.18
5.95
5.41
5.95
4.90
5.09
6.41
6.39
7.09
6.88
5.66
6.13
5.91
7.53
4.56
4.52

648
6
4
29
59
16
16
14
16
80
30
23
20
3
4
3
3
5
3
8
7
2
2
1
2
4
3
3
1
11
11

3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50
3.50

*1: Including long-beaked common dolphin

32

Table 5. Estimated the annual prey consumption based on three methods.
5-1. Southern Hemisphere including Indian Ocean
SpeciesBlue whale
Pigmy blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Southern right whale
Pygmy right whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Arnoux's beaked whale
Southern bottlenose whale*2
Beaked whales
Cuvier's beaked whale
Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale
Hector's beaked whale
Pygmy beaked whale
True's beaked whale
Strap-toothed whale
Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
TucuxiIndo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin
Hourglass dolphin
Peale's dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin*3Common dolphin
Fraser's dolphin
Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin
Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoise
Finless porpoise
Toothed whales total
Cetaceans total

Average body Abundance
weight (kg)
102,737
102,737
55,59016,811
16,1436,566
30,40823,383N.d.
*126,939
177
101
1,733
1,079
1,406
829
N.D.
449
501
376
294
N.D.
445
631
334
1,069
87
2,281
851
643
578
98
105
39
115
92
50
34
59
224
188
65
66
41
47
116
80
95
62
28
33
67
31
58
42
41

1,255
5,000
85,20010,86089,000761,000
10,0007,000
N.d.
209,000
N.d.
N.d.
N.d.
N.d.
599,000
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
58,50086,500
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
144,000
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
N.d.
3,211
N.d.
3,408
N.d.
N.d.
N.d.
N.d.

*1: Only average weight of male (26,939kg)*2: Arnoux's beaked whale + Southern bottlenose whale*3: Including long-beaked common dolphin

33

Method-1(tons)

Method-2(tons)

Method-3(tons)

438,574
1,747,307
19,730,111
1,128,547
9,000,810
42,122,913
1,545,767
907,410714,615
2,847,073
29,992,901
1,498,705
11,898,389
50,301,128
2,194,957
1,250,816

1,647,144
6,562,326
60,505,824
2,332,299
18,354,187
63,833,175
3,884,622
2,091,025

76,621,439
29,788,184

100,698,584
35,635,138

159,210,602
71,926,457

11,806,445

10,116,791

10,759,028

1,594,564
1,217,898

1,443,150
986,040

1,704,677
940,387

234,420

131,90362,546

4,590

2,526

1,149

8,740

5,310

2,917

44,654,841
121,276,280

48,320,858
149,019,442

85,397,161
244,607,762

5-2. North Pacific
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Gray whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Baird's beaked whale
Cuvier's beaked whale
Blainville's beaked whale
Ginkgo-toothed beaked whale
Hubbs' beaked whale
Stejneger's beaked whale
Killer whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin
Rough-toothed dolphin
Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Spinner dolphin
Striped dolphin*1Common dolphin
Fraser's dolphin
Northern right whale dolphin
Dall's porpoise
Harbour porpoise
VaquitaFinless porpoiseWhite whale
Toothed whales total
Cetaceans total

Average body Abundance
weight (kg)
102,737
55,59016,811
16,1436,566
30,40823,38331,076
15,372

3,300
16,125
9,110
34,92432,600
7,000
1,200
7,500
26,30018,519
177
101
3,137
829
449
376
470
455
2,281
643
578
98
105
115
92
78
224
188
65
41
116
80
95
105
61
31
22
41
313

124,778
N.D.
11,2155,870
20,000
N.D.
N.D.
N.D.
N.D.
8,500
53,60856,46838,90045,400N.D.
145,900
988,000
372,589412,291
2,497,164
1,651,100
2,488,038
2,664,300
289,300
308,000
1,740,000
N.D.
N.D.
5,000
32,800*1: Including long-beaked common dolphin

34

Method-1(tons)

Method-2(tons)

Method-3(tons)

1,153,222
3,734,132
946,691
3,531,958
1,804,477
1,082,037
155,556
1,176,327
2,573,992
16,158,393
13,835,152

1,604,869
4,848,145
1,073,746
3,987,669
1,840,381
1,312,263
183,136
1,430,124
2,890,075
19,170,407
15,864,486

4,331,135
11,451,366
1,956,468
7,202,266
2,734,509
2,719,235
358,461
2,977,469
5,164,723
38,895,634
29,520,007

37,865
198,082
276,697

24,095
185,846
223,358

14,470235,241
211,810

231,689625,566
613,531
128,710
157,324

209,688
490,684
475,483
81,625100,552

247,688
440,354
416,957
48,70160,898462,738
2,805,450
2,145,055
2,110,726
6,275,396
3,047,058
9,216,924
7,694,769
937,487
1,067,308
4,190,467

291,370
1,733,846
1,493,543
1,440,831
3,799,283
1,751,163
5,957,596
4,769,206
592,447
682,159
2,518,871

171,476
984,493
1,066,201
990,199
2,073,583
864,805
3,687,024
2,722,915
351,102413,144
1,355,939

9,227
236,282
56,303,501
72,461,894

5,303
170,855
42,862,292
62,032,699

2,619
131,153
46,010,777
84,906,410

5-3. North Atlantic
Species

Average bodyweight (kg)Abundance

102,737
55,59016,811
16,1436,566
30,40823,38331,076330
47,3004,000
N.D.
149,000
10,600400
45018,519
177
101
829
1,689
449
455
393
445
2,281
851
643
578
98
105
77
92
142
92
224
188
65
66
41
47
116
80
95
31
313
325

190,000
N.D.
N.D.
N.D.
44,300
N.D.
N.D.
N.D.
N.D.
5,500
778,000
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
13,42038,680
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
N.D.
28,51055,20029,300Blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale
Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Atlantic hump-backed dolphin
Rough-toothed dolphin
White beaked dolphin
Atlantic white sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin
Common dolphin*1
Fraser's dolphin
Harbour porpoiseWhite whale
NarwhalToothed whales total
Cetaceans total

Method-1(tons)

Method-2(tons)

Method-3(tons)

115,322
10,953,453
415,671

160,487
14,221,225
471,458

433,11433,590,674
859,042

8,247,456
1,638,513
51,85270,58021,492,847
21,066,845

8,411,556
1,987,142
61,04585,80725,398,720
24,156,922

12,498,217
4,117,699
119,487
178,648
51,796,881
44,950,243

987,320

863,736

955,860

149,916
10,954,046

135,6818,868,658

160,269
8,458,046

56,928
122,678

37,64877,24624,34545,461

43,627
397,645
216,457
33,995,462
55,488,310

24,293
287,537
157,187
34,608,907
60,007,627

11,291
220,721
121,650
54,947,885
106,744,767*1: Including long-beaked common dolphin

5-4. Total
Region

Method-1(tons)Southern Hemisphere including Indian Ocean
Baleen whales
Toothed whales
Cetacean total
North PacificBaleen whales
Toothed whales
Cetacean total
North Atlantic
Baleen whales
Toothed whales
Cetacean total
Total
Baleen whales
Toothed whales
Cetacean total

35

Method-2(tons)

Method-3(tons)

76,621,439
44,654,841
121,276,280

100,698,584
48,320,858
149,019,442

159,210,602
85,397,161
244,607,762

16,158,393
56,303,501
72,461,894

19,170,407
42,862,292
62,032,699

38,895,634
46,010,777
84,906,410

21,492,847
33,995,462
55,488,310

25,398,720
34,608,907
60,007,627

51,796,881
54,947,885
106,744,767

114,272,679
134,953,804
249,226,484

145,267,711
125,792,057
271,059,768

249,903,117
186,355,822
436,258,939

Table 6. Assumed prey composition (% of weght) of cetaceans in each Region
6-1. Southern Hemisphere including Indian Ocean
SpeciesBlue whale
Pigmy blue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Southern right whale
Pygmy right whale
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Arnoux's beaked whale
Southern bottlenose whale*1
Beaked whales
Cuvier's beaked whale
Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale
Hector's beaked whale
Pygmy beaked whale
True's beaked whale
Strap-toothed whale
Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
TucuxiIndo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin
Hourglass dolphin
Peale's dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin*2Common dolphin
Fraser's dolphin
Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin
Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoise
Finless porpoise

Fish

Cephalopoda Crustacean

Others

100.0
100.0
99.5
99.8
53.0
100.0
100.0
100.0
100.0
5.0
5.0
10.0
10.0
20.0
15.0
10.0

0.5
0.2
47.0

SourceNemoto and Kawamura 1977
Kawamura 1994
Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Kawamura 1980
Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Nemoto 1959
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

25.0
20.0
10.0
60.0
20.0
40.0
30.0

70.0
75.0
80.0
30.0
60.0
45.0
60.0

50.0

50.0

Pauly et al . 1998

20.0

80.0

Pauly et al . 1998

30.0

100.0
70.0

Pauly et al . 1998
Pauly et al . 1998

70.0
50.0
25.0
40.0
50.0
30.0
30.0
70.0
90.0
60.0
80.0
50.0
50.0
10.0
75.0
50.0
50.0
60.0
50.0
60.0
70.0
60.0
50.0
50.0
60.0
50.0

10.0
10.0
75.0
60.0
50.0
50.0
70.0
10.0

60.0
50.0

30.0
40.0

*1: Arnoux's beaked whale + Southern bottlenose whale*2: Including long-beaked common dolphin

Pauly et al . 1998

20.0

5.0

Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Odell and McClune 1999
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Brownell and Donahue 1999
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

10.0
10.0

Pauly et al . 1998
Pauly et al . 1998

40.0

20.0
20.0
10.0
10.0

30.0
20.0
50.0
40.0
85.0
25.0
50.0
50.0
40.0
40.0
35.0
30.0
35.0
50.0
30.0
40.0
45.0

10.0
5.0

10.0
5.0
5.0
20.0

36

6-2. North Pacific
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Gray whale
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Baird's beaked whale
Cuvier's beaked whale
Blainville's beaked whale
Ginkgo-toothed beaked whale
Hubbs' beaked whale
Stejneger's beaked whale
Killer whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin
Rough-toothed dolphin
Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Spinner dolphin
Striped dolphin*1Common dolphin
Fraser's dolphin
Northern right whale dolphin
Dall's porpoise
Harbour porpoise
VaquitaFinless porpoiseWhite whale

Fish

5.0
3.4
11.1
70.0
17.2

5.0
25.0
20.0
10.0
35.0
30.0
50.0
20.0
5.0
50.0
40.0
50.0
30.0
30.0
90.0
60.0
65.0
10.0
75.0
50.0
60.0
60.0
70.0
60.0
50.0
55.0
75.0
50.0
50.0
70.0

Cephalopoda Crustacean

Others

100.0
93.3
95.4
88.9
30.0
82.8
100.0
100.0
95.0
5.0
5.0
10.0
10.0
10.0

1.7
1.2

70.0
75.0
80.0
55.0
60.0
50.0
80.0
95.0
10.0
60.0
50.0
50.0
70.0

Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Tamura and Fujise 2000a
Nemoto and Kawamura 1977
Nemoto and Kawamura 1977
Nemoto 1959
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

40.0

20.0
10.0
10.0

30.0
35.0
85.0
25.0
50.0
40.0
35.0
30.0
35.0
50.0
40.0
20.0
50.0
40.0
10.0

5.0

5.0
5.0
5.0
5.0
10.0
20.0

*1: Including long-beaked common dolphin

37

SourcePauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Odell and McClune 1999
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

6-3. North Atlantic
SpeciesBlue whale
Fin whale
Sei whale
Bryde's whale
Minke whale
Humpback whale
Northern right whale
Bowhead whale
Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale
Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale
Short-finned pilot whale
False killer whale
Pygmy killer whale
Melon-headed whale
Atlantic hump-backed dolphin
Rough-toothed dolphin
White beaked dolphin
Atlantic white sided dolphin
Risso's dolphin
Bottlenose dolphin
Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin
Common dolphin*1
Fraser's dolphin
Harbour porpoiseWhite whale
NarwhalFish

Cephalopoda Crustacean
100.0
97.0
98.0
88.9
41.0
40.0
100.0
100.0
5.0
5.0
10.0
10.0
15.0

3.0
2.0
11.1
59.0
60.0

25.0
20.0
10.0
30.0
15.0
50.0
45.0

50.0
25.0
40.0
50.0
30.0
30.0
100.0
60.0
75.0
65.0
10.0
75.0
50.0
50.0
60.0
50.0
60.0
70.0
60.0
75.0
70.0
35.0

Others

70.0
75.0
80.0
60.0
70.0
50.0
55.0
100.0
10.0
75.0
60.0
50.0
50.0
70.0

Sigurjónsson and Víkingsson 1998
Sigurjónsson and Víkingsson 1998
Sigurjónsson and Víkingsson 1998
Nemoto and Kawamura 1977
Sigurjónsson and Víkingsson 1998
Sigurjónsson and Víkingsson 1998
Nemoto 1959
Nemoto 1959
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

40.0

20.0

30.0
20.0
25.0
85.0
25.0
50.0
50.0
40.0
40.0
35.0
30.0
35.0
20.0
10.0
50.0

10.0
5.0
10.0
5.0

10.0
5.0
5.0
5.0
20.0
15.0

*1: Including long-beaked common dolphin

38

SourcePauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Odell and McClune 1999
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998
Pauly et al . 1998

Table 7. Estimated the annual prey consumption based on three methods.
7-1. Southern Hemisphere including Indian Ocean
Species

Abundance
Fish

Method-1
Cephalopoda Crustacean

Fish

Method-2
Cephalopoda Crustacean

Method-3
Cephalopoda Crustacean

FishBlue whale
Pigmy blue whale
Fin whale

1,255
5,000
85,2000098,651000438,574
1,747,307
19,631,460

00149,965000714,615
2,847,073
29,842,936

00
302,5290001,647,144
6,562,326
60,203,295

Sei whale
Bryde's whale
Minke whale
Humpback whale

10,86089,000761,000
10,0002,257
4,230,381
0
0

0
0
0
0

1,126,290
4,770,429
42,122,913
1,545,767

2,997
5,592,243
0
0

0
0
0
0

1,495,707
6,306,146
50,301,128
2,194,957

4,665
8,626,468
0
0

0
0
0
0

2,327,635
9,727,719
63,833,175
3,884,622

Southern right whale
Pygmy right whale
Baleen whales total

7,000
N.d.

0
0
4,331,288

000907,410072,290,150

005,745,205

0001,250,816
0
94,953,379

008,933,662

0002,091,0250
150,276,940

Sperm whale
Pygmy sperm whale
Dwarf sperm whale
Arnoux's beaked whale

209,000
N.d.
N.d.
N.d.

7,447,046

20,851,729

1,489,409

8,908,785

24,944,597

1,781,757

17,981,614

50,348,520

3,596,323

Southern bottlenose whale*1
Beaked whales
Cuvier's beaked whale

N.d.
599,000
N.d.

4,722,578

5,312,900

1,770,967

4,046,717

4,552,556

1,517,519

4,303,611

4,841,563

1,613,854

Shepherd's beaked whale
Blainville's beaked whale
Gray's beaked whale
Ginkgo-toothed beaked whale

N.d.
N.d.
N.d.
N.d.

Hector's beaked whale
Pygmy beaked whale
True's beaked whale

N.d.
N.d.
N.d.

Strap-toothed whale
Andrew's beaked whale
Longman's beaked whale
Irrawaddy dolphin

N.d.
N.d.
N.d.
N.d.

Killer whale
Long-finned pilot whale
Short-finned pilot whale

58,50086,500N.d.

797,282
304,475

159,456
913,42400721,575
246,510

144,315
739,53000852,338
235,097

170,468
705,29000False killer whale
Pygmy killer whale
Melon-headed whale
Tucuxi

N.d.
N.d.
N.d.
N.d.

Indo-Pacific hump-backed dolphin
Rough-toothed dolphin
Dusky dolphin

N.d.
N.d.
N.d.

Hourglass dolphin
Peale's dolphin
Risso's dolphin
Bottlenose dolphin

144,000
N.d.
N.d.
N.d.

117,210

117,210065,951

65,951031,27331,2730Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin

N.d.
N.d.
N.d.

Clymene dolphin
Striped dolphin*2Common dolphin
Fraser's dolphin

N.d.
N.d.
N.d.
N.d.

Southern right whale dolphin
Commerson's dolphin
Heaviside's dolphin

N.d.
3,211
N.d.

2,295

1,377

918

1,263

758

505

574

345

230

Hector's dolphin
Black dolphin
Spectaced porpoise
Burmeister's porpoise

3,408
N.d.
N.d.
N.d.

4,370

3,933

437

2,655

2,389

265

1,458

1,313

146

Finless porpoise
Toothed whales total
Cetaceans total

N.d.
13,395,256
17,726,544

27,360,029
27,360,029

3,261,731
75,551,881

13,993,455
19,738,660

30,450,096
30,450,096

3,300,046
98,253,426

23,405,967
32,339,628

56,098,771
56,098,771

5,210,553
155,487,492*1: Arnoux's beaked whale + Southern bottlenose whale*2: Including long-beaked common dolphin397-2. North Pacific
Species

Abundance

Method-1
Cephalopoda Crustacean

Fish

Method-2
Cephalopoda Crustacean

Fish

Method-3
Cephalopoda Crustacean

FishBlue whale

3,300

0

0

1,153,222

001,604,869

004,331,135

Fin whale
Sei whale
Bryde's whale
Minke whale

16,125
9,110
34,92432,600186,707
32,187392,047
1,263,134

63,48011,360003,483,945
903,143
3,139,911
541,343

242,40736,507
442,631
1,288,266

82,41812,885004,523,319
1,024,354
3,545,038
552,114572,568
66,520799,451
1,914,156

194,673
23,47800

10,684,125
1,866,471
6,402,814
820,353

Humpback whale
Northern right whale
Bowhead whale
Gray whale

7,000
1,200
7,500
26,300186,11000128,7000000895,927
155,556
1,176,327
2,445,293

225,70900
144,50400
0
0

1,086,554
183,136
1,430,124
2,745,571

467,70800258,23600002,251,527
358,461
2,977,469
4,906,487

Baleen whales total
Sperm whale
Pygmy sperm whale
Dwarf sperm whale

124,778
N.D.
11,2152,188,885
3,458,788

74,841
9,684,606

13,894,667
691,758

2,380,025
3,966,122

95,303
11,105,140

16,695,079
793,224

4,078,641
7,380,002

218,151
20,664,005

34,598,842
1,476,000

Baird's beaked whale
Cuvier's beaked whale
Blainville's beaked whale
Ginkgo-toothed beaked whale

5,870
20,000N.D.
N.D.

Hubbs' beaked whale
Stejneger's beaked whale
Killer whale
Short-finned pilot whale

N.D.
N.D.
8,500
53,608

False killer whale
Pygmy killer whale
Melon-headed whale
Indo-Pacific hump-backed dolphin

3,786

30,292

3,786

2,409

19,276

2,409

1,447

11,576

1,447

69,32983,009108,945
166,018

19,80827,67065,04667,007102,215
134,015

18,58522,33682,33463,543

129,383
127,086

23,524
21,181

115,844
250,226

23,169375,34000104,844
196,274

20,969294,41100123,844
176,141

24,769264,2120056,46838,90045,400N.D.

306,765
38,61347,197306,765
64,355
110,127000237,742
24,48730,166

237,742
40,81270,38600
0

208,478
14,61018,270208,478
24,35042,629000Rough-toothed dolphin
Pacific white-sided dolphin
Risso's dolphin
Bottlenose dolphin

145,900
988,000
372,589412,291

277,643
1,823,542
214,505
1,583,044

138,821981,907
1,823,296
527,681

46,274
0
107,2530

174,822
1,127,000
149,354
1,080,623

87,411
606,846
1,269,511
360,208

29,137
074,677
0102,886
639,920
106,620742,649

51,443
344,572
906,271247,550

17,148053,3100Pantropical spotted dolphin
Spinner dolphin
Striped dolphin*1Common dolphin

2,497,164
1,651,100
2,488,038
2,664,300

3,137,698
1,828,235
5,530,155
5,386,338

3,137,698
1,218,823
3,225,923
2,308,431

00460,8460

1,899,642
1,050,698
3,574,558
3,338,444

1,899,642
700,465
2,085,159
1,430,762

00297,88001,036,791
518,883
2,212,214
1,906,040

1,036,791
345,922
1,290,458
816,87400184,3510

Fraser's dolphin
Northern right whale dolphin
Dall's porpoise
Harbour porpoise289,300
308,000
1,740,000
N.D.

562,492
533,6542,304,757

328,121533,654
1,676,187

46,874
0
209,523

355,468
341,079
1,385,379

207,356
341,079
1,007,549

29,6220125,944

210,661
206,572
745,766

122,886
206,572
542,375

17,5550
67,797

4,614
165,397
27,725,633
29,914,518

3,691
23,62826,797,479
26,872,320

923
47,256
1,661,972
15,556,639

2,652
119,599
19,293,415
21,673,440

2,121
17,08622,040,161
22,135,464

530
34,171
1,428,515
18,123,594

1,309
91,807
16,590,790
20,669,430

1,048
13,11527,422,366
27,640,517

262
26,231
1,888,806
36,487,648

VaquitaFinless porpoiseWhite whale
Toothed whales total
Cetaceans total

N.D.
5,000
32,800*1: Including long-beaked common dolphin407-3. North Atlantic
Species

Abundance
Fish

Method-1
Cephalopoda Crustacean

Fish

Method-2
Cephalopoda Crustacean

Fish

Method-3
Cephalopoda CrustaceanBlue whale
Fin whale

330
47,3000328,6040
0

115,322
10,624,850

0426,63700160,487
13,794,588

0
1,007,720

00433,11432,582,954

Sei whale
Bryde's whale
Minke whale
Humpback whale

4,000
N.D.
149,565
10,6008,313

0407,3589,429

0462,029

17,1810841,861

4,884,451
983,108003,394,279
655,405

4,981,637
1,192,285

003,461,815
794,857

7,401,910
2,470,620

005,143,700
1,647,080

006,204,476
5,266,711

00014,746,792

51,85270,58015,319,646
1,053,342

00
6,609,988
6,039,231

000
16,909,845

61,04585,807
18,820,629
1,207,846

0010,897,430
11,237,561

000
31,465,170

119,487
178,648
40,946,844
2,247,512

148,098

691,124

148,098

129,560

604,615

129,560

143,379

669,102143,379

74,9582,738,511

14,9928,215,534

0067,8402,217,165

13,5686,651,494

0080,134
2,114,512

16,027
6,343,535

0042,696
79,741

11,38630,6692,846
12,26828,23650,2107,530
19,311

1,882
7,725

18,25829,5494,869
11,365

1,217
4,546

32,720278,352
75,7608,725
39,765108,228

2,181
79,52932,46918,220201,276
55,0154,859
28,75478,593

1,215
57,507
23,578

8,468
154,505
42,577

2,258
22,07260,825565
44,144
18,2478,737,547
14,942,023

23,867,215
23,867,215

1,330,733
16,650,379

8,806,752
15,416,740

24,318,569
24,318,569

1,429,314
20,249,942

13,828,944
24,726,374

38,595,223
38,595,223

2,459,611
43,406,455

Northern right whale
Bowhead whale
Baleen whales total
Sperm whale
Pygmy sperm whale

190,000
N.D.

Dwarf sperm whale
Cuvier's beaked whale
Northern bottlenose whale
Blainville's beaked whale
Sowerby's beaked whale

N.D.
N.D.
44,300N.D.
N.D.

Gervais' beaked whale
True's beaked whale
Killer whale
Long-finned pilot whale
Short-finned pilot whale

N.D.
N.D.
5,500
778,000
N.D.

False killer whale
Pygmy killer whale
Melon-headed whale
Atlantic hump-backed dolphin
Rough-toothed dolphin

N.D.
N.D.
N.D.
N.D.
N.D.

White beaked dolphin
Atlantic white sided dolphin
Risso's dolphin
Bottlenose dolphin

13,42038,680N.D.
N.D.

Pantropical spotted dolphin
Atlantic spotted dolphin
Spinner dolphin
Clymene dolphin
Striped dolphin

N.D.
N.D.
N.D.
N.D.
N.D.

Common dolphin
Fraser's dolphin
Harbour porpoiseWhite whale
Narwhal

*1

400
450

N.D.
N.D.
28,51055,20029,300Toothed whales total
Cetaceans total*1: Including long-beaked common dolphin

7-4. Total
RegionFish

Method-1
Cephalopoda Crustacean

Fish

Method-2
Cephalopoda Crustacean

Fish

Method-3
Cephalopoda CrustaceanSouthern Hemisphere including Indian Ocean
Baleen whales
Toothed whales
Cetacean total
North Pacific

4,331,288
13,395,256
17,726,544

0
27,360,029
27,360,029

72,290,150
3,261,731
75,551,881

5,745,205
13,993,455
19,738,660

030,450,096
30,450,096

94,953,379
3,300,046
98,253,426

8,933,662
23,405,967
32,339,628

0
56,098,771
56,098,771

150,276,940
5,210,553
155,487,492

Baleen whales
Toothed whales
Cetacean total
North Atlantic
Baleen whales

2,188,885
27,725,633
29,914,518

74,841
26,797,479
26,872,320

13,894,667
1,661,972
15,556,639

2,380,025
19,293,415
21,673,440

95,30322,040,161
22,135,464

16,695,079
1,428,515
18,123,594

4,078,641
16,590,790
20,669,430

218,151
27,422,366
27,640,517

34,598,842
1,888,806
36,487,648

6,204,476

0

15,319,646

6,609,988

0

18,820,629

10,897,430

040,946,844

Toothed whales
Cetacean total

8,737,547
14,942,023

23,867,215
23,867,215

1,330,733
16,650,379

8,806,752
15,416,740

24,318,569
24,318,569

1,429,314
20,249,942

13,828,944
24,726,374

38,595,223
38,595,223

2,459,611
43,406,455

Total
Baleen whales
Toothed whales
Cetacean total

12,724,649
49,858,436
62,583,085

74,841
78,024,723
78,099,564

101,504,463
6,254,436
107,758,899

14,735,218
42,093,622
56,828,840

95,30376,808,827
76,904,130

130,469,087
6,157,875
136,626,962

23,909,733
53,825,700
77,735,433

218,151
122,116,359
122,334,510

225,822,626
9,558,969
235,381,595

41

NA
NP

SHIO

Fig.1. Map of major fishing areas for statistical purposes and ocean regions in this study, based on FAO (FAO, 1991).

42