U. S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

October 2005

Report of the

International Cachalot Assessment

Research Planning Workshop,

Woods Hole, Massachusetts,

1-3 March 2005

Tim D. Smith

Randall R. Reeves

John L. Bannister

Editors

U.S. DEPARTMENT OF COMMERCE

Carlos M. Gutierrez, Secretary

National Oceanic and Atmospheric Administration

Vice Admiral Conrad C. Lautenbacher, Jr., USN (ret.), Under Secretary for Oceans and Atmosphere

National Marine Fisheries Service

William T. Hogarth, Assistant Administrator for Fisheries

October 2005

NOAA Technical Memorandum NMFS-F/SPO-72

Report of the International Cachalot

Assessment Research Planning Workshop,

Woods Hole, Massachusetts, 1-3 March 2005

Tim D. Smith1, Randall R. Reeves2, and John L. Bannister3, Editors

1 National Marine Fisheries Service, 166 Water St., Woods Hole, Massachusetts 02543, USA

2 Okapi Wildlife Associates, 27 Chandler Ln., Hudson, Quebec I0P 1H0, CANADA

3 The Western Australia Museum, Francis St., Perth, Western Australia 6000, AUSTRALIA
The preparation of this document was supported jointly by the US Marine Mammal 

Commission and the US National Marine Fisheries Service. MMC support was through 

Grant No. 19Z007 to the University of New Hampshire, Professor A.A. Rosenberg and 

Affiliate Professor Tim D. Smith, Principal Investigators. NMFS support was through the 

Protected Species Branch of the Northeast Fisheries Science Center, Woods Hole, MA.

This document will initially be issued only online. It will be available at:

http://www.nefsc.noaa.gov/nefsc/publications/online.htm

It will be available in PDF format so that a paper copy can be easily printed out. It may

subsequently be issued on paper as well. If it is issued on paper, then copies would be

available from:

Protected Species Branch

Northeast Fisheries Science Center

National Marine Fisheries Service, NOAA

166 Water St.

Woods Hole, MA 02543

This document may be cited as:

Smith, TD; Reeves, RR; Bannister, JL, Editors. 2005. Report of the International Cachalot

Assessment Research Planning Workshop, Woods Hole, Massachusetts, 1-3 March 2005.

U.S. Dep. Commerce, NOAA Tech. Memo. NMFS-F/SPO-72, 45 p.
Page iii

CONTENTS

1. Welcome ......................................................................................................................................................................1

2. Review Terms of Reference, Agenda, Available Documentation, and Meeting Arrangements ....................................1

3. Introduction of Workshop Chair and Rapporteur ........................................................................................................2

4. Overviews ....................................................................................................................................................................2

5. Population Structure and Movements .........................................................................................................................3

5.1 Tagging ................................................................................................................................................................3

5.2 Individual Identification .......................................................................................................................................4

5.3 Acoustic ...............................................................................................................................................................5

5.4 Morphology .........................................................................................................................................................5

5.5 Genetics ...............................................................................................................................................................6

5.6 Historical Evidence ..............................................................................................................................................6

5.7 Other ....................................................................................................................................................................6

6. Abundance and Distribution .......................................................................................................................................6

6.1 Whaling Records .................................................................................................................................................6

6.2 Genetic Diversity ..................................................................................................................................................7

6.3 Sightings and Acoustics Surveys, Including Dive Cycle ....................................................................................7

6.4 Individual Identification .......................................................................................................................................9

7. Life History ..................................................................................................................................................................9

7.1 Age Determination ...............................................................................................................................................9

7.2 Vital Rates .......................................................................................................................................................... 10

7.3 Social Structure .................................................................................................................................................. 10

8. Population Ecology .................................................................................................................................................... 11

8.1 Feeding .............................................................................................................................................................. 11

8.2 Diving Physiology ............................................................................................................................................. 12

9. Human Interactions .................................................................................................................................................... 13

9.1 20th Century Whaling ........................................................................................................................................ 13

9.2 Pre-20th Century Whaling.................................................................................................................................. 14

9.3 Interactions with Fisheries and Shipping ........................................................................................................... 15

9.4 Environmental Issues ......................................................................................................................................... 16

10. Field Programs ........................................................................................................................................................... 17

10.1 Gulf of Mexico .................................................................................................................................................... 17

10.2 Mediterranean Sea ............................................................................................................................................. 18

10.3 Eastern North Pacific .......................................................................................................................................... 18

10.4 Western North Pacific ........................................................................................................................................ 19

10.5 Western North Atlantic and Caribbean .............................................................................................................. 19

10.6 Eastern and Central North America (including Iceland) ..................................................................................... 20

10.7 South Pacific ...................................................................................................................................................... 20

10.8 Odyssey .............................................................................................................................................................. 21

10.9 Indian Ocean ...................................................................................................................................................... 22

10.10 Antarctic ........................................................................................................................................................... 22

11. Future Work ............................................................................................................................................................... 22

11.1 Need to Understand the True, Underlying Structure of Populations ................................................................. 22

11.2 Need to Obtain Accurate Estimates of the Numbers of Whales Removed by Whaling from Each Population .. 23

11.3 Need to Estimate Abundance for a High Proportion of Waters Worldwide ....................................................... 23

11.4 Need to Improve Understanding of the Demographics of Population Growth .................................................. 24

11.5 Need to Develop Sperm Whale Population Models ........................................................................................... 25

11.6 Biological Significance of Present-Day "Changes" ........................................................................................... 26

11.7 Implementing Components of Needed Research ............................................................................................... 27

12. Top Priorities for Future Work ................................................................................................................................... 30

13. References Cited ........................................................................................................................................................ 32
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TABLES

Table 1. Analyses facilitated by biopsies, with handling and storage procedures ............................................................. 27

Table 2. Research tasks by general category to be addressed in preparation for in-depth assessment of sperm whale

populations .......................................................................................................................................................... 31

ANNEXES

Annex 1: List of Participants .............................................................................................................................................. 37

Annex 2: Agenda................................................................................................................................................................ 39

Annex 3: List of Documents ............................................................................................................................................... 40

Annex 4: A Brief History of the IWC Scientific Committee’s Assessments of Sperm Whales ........................................... 43

Annex 5: Comparison of Photo-Identification and Biopsy Sampling ................................................................................. 44
Page 1

1. WELCOME

Smith welcomed participants on behalf of the conveners (Smith and Reeves). Despite a major snowstorm in the

New England region, nearly everyone was able to arrive

safely and on time. The list of participants is given in Annex

1.

Clapham spoke briefly about the life of Bill Watkins, an

esteemed scientist at the Woods Hole Oceanographic Institution and pioneer of research on sperm whale behavior.

For many workshop participants, Bill’s death in late September 2004 meant the loss of a valued and generous colleague. He was an innovative and influential force in the

fields of marine bioacoustics and telemetry, a great editor, a

unique resource, and a remarkable man. As such, he will be

missed by many of us in the marine mammal community.

Kerr and Godard spoke briefly about Rebecca Clark, a young

scientist killed by the tsunami in December 2004 while working on a sea turtle project in Thailand. She had been associated with the voyage of the Odyssey since 1999. Kerr recalled that after sailing from the Galápagos to the Marquesas

(54 days at sea) and spending only four days on shore in

“paradise,” Rebecca had been eager to resume the voyage.

She is remembered as an enthusiastic, meticulous,

hardworking, and good-humored colleague. Bannister noted

that the Australian Government and its Department of the Environment and Heritage had asked to be associated with the

remembrance of Rebecca Clark at this workshop.

2. REVIEW TERMS OF REFERENCE,

 AGENDA, AVAILABLE

 DOCUMENTATION, AND MEETING

 ARRANGEMENTS

The terms of reference for the workshop, developed by

a steering group within the International Whaling

Commission’s Scientific Committee, were as follows:

• Identify and evaluate new methods, identify critical tests

of such methods, and describe how these might be conducted, especially using combinations of new methods

simultaneously.

• Identify relevant spatial scales and formulate plans for

regional field studies to address key uncertainties relevant to an eventual In-depth Assessment.

• Develop a research program that would be necessary

and sufficient as the basis for an In-depth Assessment

of sperm whales, including research coordination and

funding mechanisms.

Smith placed the workshop and its terms of reference in

a wider context, citing contributory rationales, as follows:

• Since the early 1980s when the IWC Scientific Committee last attempted to assess sperm whale stocks, individual researchers and a few independent programs

have made steady progress toward a better understanding of sperm whale biology, behavior, ecology, and population dynamics. This has required development of

novel methods for studying live, free-ranging sperm

whales, and the availability of such methods offers new

possibilities for research planning.

• Sperm whales are no longer high on the IWC Scientific

Committee’s agenda, given that commercial whaling on

the species stopped with the moratorium that took effect in the Antarctic in 1983 and elsewhere in 1987. Nevertheless, the Committee has accepted the recent initiative, led by Smith and a small group of colleagues, to at

least begin preparing the background for an eventual

in-depth assessment of sperm whale populations.

• There is interest within the U.S. Federal Government in

reassessing the sperm whale’s status under the Endangered Species Act. The sperm whale is one of several

species of large whales (also the humpback whale and

fin whale) that are listed as Endangered but for which

credible supporting documentation is lacking. There is

interest in determining whether this listing is warranted

and in completing a long-delayed recovery plan.

• The sperm whale is classified in the IUCN Red List as

Vulnerable, but again, the documentation to justify that

status has not been provided. A global assessment of

the species and a regional assessment of the Mediterranean population have been underway for some time

within the Cetacean Specialist Group of the IUCN (World

Conservation Union) Species Survival Commission, and

both have proven controversial.

• Sperm whales are subject to an array of threats from

human activities. Sperm whales are hunted today only

on a very limited scale (e.g., in Indonesia – Barnes 1996;

the western North Pacific – CARP/FP/6), and they are

killed occasionally by gillnets and ship collisions. Their

depredation on demersal longlines has put them in conflict with fisheries in the Gulf of Alaska (black cod) and

the Southern Ocean (toothfish). Further, like other cetaceans, sperm whales are contaminated by a variety of

potentially toxic manmade chemicals, and there is increasing concern about the potential effects of underwater noise on sperm whales (e.g., from offshore oil

and gas development).

• A subproject of the Alfred E. Sloan Foundation’s Census of Marine Life, called History of Marine Animal

Populations or HMAP, has sparked interest in studying the history of whaling in order to better understand

the impacts on whale populations and, in turn, marine

ecosystems. An HMAP-sponsored workshop in 2002

(Smith and Reeves 2003; CARP/HI/5, CARP/HI/12) cited

the need for a workshop “on sperm whale population

biology, ecology and abundance to determine regional

population structure.”

All of the factors listed above helped lay the groundwork and provided impetus for the workshop. The conven-
Page 2

ers envisaged that the results would be of interest to a

range of parties, including the IWC Scientific Committee,

agencies of the U.S. Federal Government (e.g., the National

Marine Fisheries Service, the Marine Mammal Commission,

and the Minerals Management Service), IUCN, fishery management and advocacy bodies, the oil and gas industry, the

world’s navies, the Census of Marine Life, and nongovernmental organizations.

The draft agenda was reviewed briefly, modified

slightly, and adopted (Annex 2).

Smith explained the scheme for classifying and numbering workshop documents, which are listed in Annex 3.

Throughout this report, documents that were prepared explicitly for the workshop are cited as CARP/.... These documents are summarized and discussed within the report, but

with no intention to distribute them (e.g., through a proceedings volume). Readers wishing to obtain copies of any

of the papers are encouraged to contact the author(s) (see

Annex 1 for contact details). Documents labeled as For Information (FI) are cited within the report in the standard

manner – author(s) and publication date/status – with full

citations in the References Cited section.

3. INTRODUCTION OF WORKSHOP

 CHAIR AND RAPPORTEUR

Bannister chaired the meeting and Reeves was rapporteur.

The task of drafting the workshop report was delegated to

Reeves and Smith, and all participants were offered an opportunity to review the draft before the report was finalized.

4. OVERVIEWS (CARP/INT)

Whitehead presented a summary and critique of his

published analysis of the global status of sperm whales

(Whitehead 2002). For that analysis, he used the available

(published) results of modern abundance surveys (mainly

shipboard line-transect) from various regions to produce a

global abundance estimate for the species. He did this by

first correcting the estimates for whales missed on the

trackline (g(0) = 0.87) and then scaling up, assuming that

about 24% of the sperm whale’s global habitat had been

adequately surveyed. He employed three different scaling

approaches – by area, assuming that all ocean areas >1000m

deep and at <70o of latitude have the same average density

of sperm whales; by Townsend’s (1935) plotted catch positions from 19th century whaling (citing Jaquet et al. 1996 as

partial justification); and by primary productivity, using

surface chlorophyll data from NOAA. A simple population

model was used to examine possible trajectories from 1999

back to 1712 when commercial sperm whaling began. He

used “best estimates” and “reasonable ranges” for input

parameters including: percentage of sperm whales in the

Atlantic (as opposed to Indo-Pacific) before modern whaling (best 33%, range 25-40%); extent of depletion in Atlantic 1712-1799 (best 33%, range 10-55%); maximum rate of

increase (best 1.1%, range 0.7-1.5%); density-dependent

exponent (best 1.4, range chosen randomly); correction factor for open-boat catch (best 1.5, range 1.1-3.0); correction

for modern catch (best taken as given, range 0.9-1.2); 1999

population size (best 360,000, range chosen from normal

distribution of 360,000 and CV = 0.36). Each model run calculated central values, along with 95% confidence intervals, for the pre-exploitation population level (1712) and the

relative levels in 1880 (when open-boat whaling was greatly

in decline) and 1999. The results suggested that there were

some 1,110,000 sperm whales (95%CI: 672,000 to 1,512,000)

in 1712, reduced by open-boat whaling to about 71% of that

(95% CI: 52 to 100%) in 1880, and further reduced by modern whaling to about 32% (95% CI: 19 to 62%) in 1999.

In his published paper, Whitehead (2002) acknowledged

that there were “some potential biases and errors which

were not fully considered” in his model and therefore that

the resulting estimates could be even less precise than indicated. He nevertheless concluded that other authors had

substantially over-estimated pre-exploitation abundance (by

a factor of two or three) and under-estimated the present

extent of depletion (by a factor of at least two). He also

acknowledged the difficulty of reconciling his modeling results showing relatively modest depletion by the early openboat fishery with the findings by Tillman and Breiwick (1983)

and Whitehead (1995), which indicated severe drops in encounter rates (about 60%) on the Japan and Galápagos sperm

whaling grounds during the first half of the 19th century

(also see Bannister et al. 1981). Whitehead (2002) concluded

in this regard that the discrepancy “may be at least partially

explained if the whales changed their schooling behavior or

distribution as exploitation progressed, or if there were refuges, such as unavailable or undiscovered grounds, where

the whales were fairly free from the whalers.”

Barlow (2003a) described the IWC Scientific Committee’s

models of sperm whale population dynamics as “among the

most complex models that have ever been used to manage

any living resource” (see Annex 4). He distinguished two

types of population models for sperm whales, each with a

different purpose. Demographic models can be used to estimate current, historical, or potential rates of population

growth. Assessment models can be used to determine the

present status of populations relative to historical population sizes. His conclusion regarding previous demographic

models, estimated from whaling statistics, was that they did

not have “a sufficiently solid foundation to be trusted without independent verification using alternative methods.”

Regarding assessment models, Barlow considered that of

Whitehead (2002) to be “exemplary” because it took full

advantage of the two “most dependably estimable parameters that affect status” – (1) current abundance from linetransect surveys and (2) numbers of whales removed by

whaling over time. Barlow identified four steps needed to
Page 3

elaborate and improve upon Whitehead’s assessment, as

follows: (1) a fundamental understanding of population

structure; (2) accurate estimates of numbers of whales of

each sex removed from each population; (3) increased survey coverage so that abundance estimates are available for

a greater proportion of the species’ range; and (4) better

understanding of sperm whale demography, particularly in

relation to the maximum rate of population growth. He also

suggested that a Bayesian population dynamics model

would provide a better way to deal with missing and uncertain data.

During the discussion of Whitehead’s presentation,

participants emphasized the desirability of using a sex-structured population model to account for the effects of the

male bias in 20th century catches. Whitehead agreed on the

desirability of such an approach, which could be expected

to show extreme depletion of adult males and less severe

depletion of females, especially post-World War II. In addition, Dawson expressed concerns about methodological

differences underlying the estimates of current abundance,

not all of which were accounted for in Whitehead’s analysis. Gunnlaugsson expressed several reservations, including his view that the abundance estimates used in the model

were negatively biased (i.e., g(0) was overestimated) and

that the “best” estimate of maximum rate of increase of 1.1%

was too low. Best observed that the data stream from whaling had stopped approximately 20 years ago and that studies of live sperm whales had, to date, provided little basis

for improving estimation of fecundity or survival. He also

pointed out that most of the field research with living sperm

whales had taken place in tropical regions, which may not

be representative of the species overall. Best emphasized

that improving certain parameter estimates would be infeasible without reference to “old” whaling data.

Further suggestions on how sperm whale assessment

models could be improved are given in section 11.5, below.

5. POPULATION STRUCTURE AND

 MOVEMENTS (CARP/PS&M)

As noted above, and as reflected in the previous call

for a workshop “to determine regional population structure” (Smith and Reeves 2003), progress in assessing the

status of sperm whales requires an improved understanding of population structure.

Mesnick presented CARP/PS&M/3, in which she and

Whitehead reviewed the various methods that have been

used to study population structure and movements in sperm

whales. Existing methods include: morphology,

morphometrics, parasite analysis, distribution of catch or

sightings data, patterns of change in catch-per-unit-effort

(CPUE) or sightings rates, mark-recapture, photo-identification, contaminant analyses, allozymes, mitochondrial

DNA (mtDNA) sequencing, and distributions of

microsatellites. Newer methods being developed include:

satellite tagging, vocal (coda) analysis, trace analysis of

tooth sections, single nucleotide polymorphisms (SNPs),

and Y-chromosome sequence variation. CARP/S&M/3 identified three specific sites where applications of one or more

of the approaches listed are underway. These are the Odyssey voyage based at the Ocean Alliance in Weston, Massachusetts (CARP/FP/4, CARP/FP/9; and see 10.8, below),

Whitehead’s laboratory at Dalhousie University in Halifax,

Nova Scotia, and Mesnick’s laboratory at the Southwest

Fisheries Science Center in La Jolla, California.

5.1 Tagging

Firing steel markers into the muscles of large whales,

including sperm whales, in the expectation that they would

be recovered when the same whales were killed and processed by the whaling industry, was a method used to study

long-range movements, migrations, and “stock identity”

before the emergence during the 1970s and 1980s of new

“non-invasive” methods such as photo-identification and

biopsy sampling (Brown 1977). Returns of these “Discovery marks” have been used only to a limited extent to inform

hypotheses concerning sperm whale population structure

(see Donovan 1991 for a review). Best pointed out that Discovery marking was largely opportunistic and was generally not designed to answer specific questions or test hypotheses.

In the North Pacific, Discovery marking was conducted

by Canada, Japan, United States, and USSR. Japanese marking began in 1949 and continued until 1979 when commercial pelagic whaling ceased. The results of Japanese Discovery marking were reported to the IWC Scientific Committee every year through the Japan Progress Reports on

Whale Research. In addition, two reviews of Japanese whale

marking results have been published (Omura and Ohsumi

1964; Ohsumi and Masaki 1975). The analysis by Kasuya

and Miyashita (1988) explicitly integrated mark-recapture

data from all four countries (as of 1987) as well as Japanese

and Soviet catch and sightings data with oceanography,

concluding that there were likely at least three sperm whale

stocks in the North Pacific – northern and southern stocks

in the west and a single stock in the east. Also, the tagging

data showed trans-equatorial movement by sperm whales

in the Pacific.

Discovery marking in the North Atlantic was not reviewed for the workshop. However, a male marked off Nova

Scotia, Canada, was later taken off northwestern Spain, some

6000km away (Mitchell 1975). Another killed off Iceland had

previously been struck by a hand harpoon in the Azores,

approximately 3000km to the south (Martin 1982). A male

Discovery-marked off Mauritania was later taken off Cape

Town, South Africa (Ivashin 1967), demonstrating transequatorial movement in the Atlantic. Mark returns have also

indicated links between the Antarctic and waters off Durban

(South Africa), and substantial latitudinal movements along

the west coast of southern Africa by both sexes (Best and

Ross 1989). Finally, Discovery mark returns have been used
Page 4

to suggest that females have smaller “home ranges”

(straight-line distances between marking and recapture) than

males (averages of 372 and 850 n. miles, respectively) (Best

1979).

Bannister commented that returns of Discovery marks

from sperm whales in the Southern Hemisphere were fewer

than expected and that this could have been a result of the

fact that the USSR program was not fully integrated with

those of other whaling nations. It could also be related to

the strategic misreporting of whale catches by the Soviet

fleet (cf. Zemsky et al. 1995).

Substantial progress has been made since 2002 on satellite tracking sperm whales, mainly in the northern Gulf of

Mexico under the direction of Bruce Mate. Animals there

have been tracked for more than a year, and battery longevity rather than tag retention is currently the main limiting

factor. Miller reported that a method was being developed

to extend battery life by generating energy from the instrumented whale’s own movement through the water. Ohsumi

noted that a sperm whale tag was being developed in Japan

by Hayashi.

After some discussion of the pros and cons of satellite

tagging, it was generally agreed that the main value is that

it provides unequivocal data on the movements of a very

small set of animals (relative to the entire population). It

shows where the animals go when they are not being monitored by direct observation. The northern Gulf of Mexico

provides an ideal context in which to approach and instrument sperm whales, but the sampling there may be biased.

For example, researchers there have not yet succeeded in

approaching and tagging large, solitary (“roving”) males,

which are likely the most wide-ranging individuals. While

satellite tagging is properly regarded as a valuable tool for

investigating population structure, it is best seen as complementary to other methods, rather than as definitive by itself.

With implantable tags, a pronounced swelling is often

observed for several months at the tagging site (for up to 11

months in one instance according to Miller). In most instances the swelling is gone and the site is “clean” thereafter. Participants with direct experience generally did not feel

that satellite tagging had any harmful long-term effects on

the whales.

There was brief discussion of VHF radio tagging of

sperm whales using suction-cup attachment. Miller explained that these tags provided detailed information on

movements and behavioral ecology for only brief periods

(up to two days). The method was, therefore, not considered relevant for investigation of population structure.

5.2 Individual Identification

Much of the discussion of this agenda item alternated

between the use of photo-identification for studying population structure and its use for abundance estimation. In

addition, the discussion often considered simultaneously

the two main types of individual identification – photographic matching and genotyping from biopsies. These two

methods were compared, with a view to evaluating their

relative strengths and weaknesses (see Annex 5).

Photo-identification has been used widely since the

1980s to trace movements (Dufault and Whitehead 1995)

and develop movement models (Whitehead 2001). Photographs of the flukes (and to some extent the back and dorsal fin) allow sperm whales to be identified individually. As

a rule of thumb, a sperm whale can be expected to raise its

flukes above the surface about once every hour (Gordon,

pers. comm.). Gordon, Jaquet, and Whitehead have acquired

extensive experience with photo-identification of sperm

whales in the northern Gulf of Mexico and Caribbean Sea,

various parts of the North Atlantic, the northern Indian

Ocean, the Gulf of California, the Galápagos, and Chile;

they have conducted their work from both large and small

vessels (e.g., CARP/PS&M/5).

Whitehead and Mesnick (CARP/PS&M/3) identified

strengths of photo-identification to include that: (1) it is

non-lethal and largely non-invasive; (2) it can be applied

inexpensively and by diverse, small-scale research operations; and (3) analytical models are already well developed

for using the data. Digital photographic technology has

greatly improved the feasibility and affordability of photoidentification. Weaknesses include: (1) marks used to identify animals can change; (2) there is a need to correct for

unevenness of effort, which reduces model precision; (3)

accuracy of identification is a function of quality of the

photograph; and (4) it can be difficult to coordinate input

from a large variety of researchers. Photo-identification is

limited as a tool for studying population structure because

each photo-identification event provides information on

the animal’s location at only a single point in time, and data

can be obtained only from areas (often near shore) where

research is being conducted.

Some participants argued that photo-identification was

impractical on the high seas far from coastlines, and for a

species so abundant and wide-ranging as the sperm whale.

This depends partly, of course, on the question being addressed and the amount of effort invested in the research.

However, participants with extensive first-hand experience

approaching and photographing sperm whales reported that

they had no difficulty obtaining fluke photographs in offshore (“pelagic”) conditions.

It was also noted that the problem of false positives, a

particular concern when applying photo-identification methods to large populations, is already addressed to some extent by the computer-assisted matching procedures that

are being used (see below). Further, all methods of assessing numerically large and wide-ranging populations have

their limitations, so those that rely on individual identification and “recapture” should not necessarily be discounted.

With regard to concerns about mark change, Dawson

(CARP/FP/1; also see item 10.7) noted that during his eight

years of photo-identification work in Kaikoura, New Zealand,

there had not been a single case where changes in markings
Page 5

were sufficient to cause difficulty with matching. He also

emphasized that all of the sperm whales in his study area

(maturing and mature males) had proven to be well enough

marked for individual photo-identification. Participants with

experience in tropical waters pointed out that mixed groups

tend to be more difficult to approach than maturing and

mature males. Discussion of the relative importance of incorporating effort to photograph the back and dorsal fin,

rather than just the flukes, was inconclusive.

Photo-identification images for the North Atlantic and

adjoining waters are coordinated within the North Atlantic

and Mediterranean Sperm Whale Catalogue (NAMSC).

NAMSC holds images from the Mediterranean and Caribbean Seas and the Gulf of Mexico. The catalog is curated by

the International Fund for Animal Welfare (contact Tim Lewis

at tlewis@ifaw.org).

Another photo-identification initiative, which to date

has been focused mainly within the eastern Atlantic and

Mediterranean areas but could be extended globally, is

Europhlukes (http://www.europhlukes.net/). Europhlukes

was a 3-year project funded by the European Community to

create a coordinated database and matching tools for cetacean photo-identification images. Sperm whales have been

a particular focus for Europhlukes, probably because of the

existence of NAMSC. Europhlukes has developed structures and tools for field databases from which subsets of

data and images can be exported to a main online database.

Automated matching tools have also been developed as

part of Europhlukes, and these are most developed for sperm

whales. Development work on automated matching is being continued by Eric Pauwels at the Centre for Mathematics and Computer Science, Amsterdam. Another initiative

from Europhlukes has been to establish a web page to allow

experience and “best practices” on photo-identification to

be exchanged among fieldworkers.

The present systems used by both Europhlukes and

Whitehead’s laboratory to compare and match photographs

of sperm whales can be characterized as semi-automated.

They still require judgments concerning the suitability of

photographs for inclusion in the catalogs, i.e., a grading

system to classify photographs according to quality and

information content. They also require a human observer to

make final decisions; perhaps this is not only unavoidable

but also desirable. Participants agreed that techniques involving a probabilistic approach to matching are both attainable and desirable, and therefore should be encouraged.

5.3 Acoustic

Mesnick introduced CARP/PS&M/2, representing an

attempt to integrate acoustic data on “vocal clans” (groups

of sperm whales that are distinguished by distinctive coda

repertoires) with genetic data. The concept of using acoustic differences as markers for population structure has been

developed previously by Weilgart and Whitehead (1997)

and Rendell and Whitehead (2003). Social codas are produced only in mixed schools of sperm whales (none by

adult males, although Gordon pointed out that the term

“coda” was first applied to patterns heard at the end of

dives by males) and therefore the vocal clans are directly

relevant only to female population structure. Drouot noted

that the coda repertoire of sperm whales in the Mediterranean Sea is different from the repertoires of Atlantic animals. Madsen stated that codas have not been recorded

from the large males off Norway, and Dawson that the maturing and mature males off Kaikoura, N.Z., rarely make coda

sounds. Barlow observed that in the Pacific, it can take 12-

24 hours of recording to obtain coda sounds; the whales

seem to produce them only when they are socializing.

Watwood, based on her experience in the North Atlantic,

Mediterranean, and Gulf of Mexico, stated that some animals produce codas at depth, and these would not necessarily be picked up by a surface hydrophone.

Some vocal clans have been found to be sympatric,

which raises the question of social philopatry and how clan

structure might relate to genetic population structure. Are

sperm whale populations structured more according to language than to geography? Rendell et al. (CARP/PS&M/2)

found statistically significant mtDNA genetic differentiation among the three vocal clans that they compared, but

none of those clans was strictly matrilineal (i.e., each clan

contained more than one haplotype). The authors concluded that more work was needed to ascertain the influence of group structure on acoustic and population structure. They identified four specific approaches to be pursued in future studies: (1) investigating group effects by

expanding sampling to include more groups within each

clan, and more clans, across a broader geographic range;

(2) investigating the relative importance of area effects (if

any) by a combined (hierarchical) group, geographical, and

clan analysis; (3) ensuring that relatedness of individuals

within groups does not violate the basic assumption that

samples are random and independent; and (4) ascertaining

whether coda dialects are more likely transmitted genetically or culturally (i.e., by learning).

Diverse views were expressed on the question of

whether codas are, in fact, appropriate markers for population structure. Groups that share coda repertoires seem to

interact preferentially, if not exclusively, with one another.

Thus, they are in some sense functional units. It is crucial

to know how codas are transmitted and whether, for example, groups of whales might just converge on a given

coda repertoire. A problem in evaluating what kind of marker

the coda might be is that when one records a coda, it usually is not possible to determine which individual in a group

has produced it.

5.4 Morphology

Rice (1989, 1998) reviewed, and dismissed as inconclusive, the evidence of population structure from morphological variation and biochemical differences in sperm whales
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at a global scale. Recognizing that a number of studies of

geographical variation had been published since, the workshop concluded that there would be value in a review and

synthesis of such information.

Ohsumi referred to his own analyses of tooth counts in

sperm whales from the Antarctic, South Georgia, Japan, and

other areas. He found no statistically significant difference

in counts across regions and therefore concluded that this

was not a promising approach for distinguishing populations.

It was suggested that the pattern of body scarring by

cookie-cutter sharks (Isistius spp.) might hold promise as a

population marker in sperm whales (as it has in killer whales).

Participants agreed that an investigation of scarring in general (e.g., from killer whales, lampreys, or cookie-cutter

sharks) might contribute to the formulation of hypotheses

concerning sperm whale population structure.

5.5 Genetics

Biopsy sampling and genetic analyses have become

standard tools for assessing population structure in whales.

Mesnick summarized CARP/PS&M/1, which describes

progress to date by “Cachalote Consortium,” a collaboration among researchers who hold genetic data on sperm

whales for the purposes of planning and carrying out investigations of global population structure in sperm whales.

Mitochondrial DNA markers (maternally inherited) and

nuclear DNA markers (biparentally inherited; e.g.,

microsatellites) are currently used widely. SNPs and Y-chromosome markers (paternally inherited) are viewed as the

most promising new tools for the immediate future.

The combined collection of material currently includes

more than 2400 tissue samples from areas including the Gulf

of California, Chile, the Galápagos, the Gulf of Mexico, the

Azores, and Tasmania. Significant gaps remain in the North

Atlantic, western Pacific, and Southern Hemisphere. A remarkable feature of preliminary analyses is the low diversity of mitochondrial DNA in sperm whales: 24 variable sites

have defined only 28 haplotypes worldwide thus far. No

fixed genetic differences have been found to differentiate

populations.

The problem of defining strata for analysis represents a

major challenge, and some of the new approaches for integrating acoustic data (coda repertoire) and genetic data

(mtDNA) were discussed in CARP/PS&M/2 (see Item 5.3,

above). Stratification by geographic and group differences

may be confounded by group vs. clan effects. An integrated

approach is needed to determine whether, and to what extent, sperm whale populations are structured socially or

geographically. To this end, understanding the function

and context of codas may be key.

There was extensive discussion of the relative merits of

photo-identification and genotyping, and a working group

was formed to summarize that discussion (Annex 5).

In addition to biopsies from living sperm whales, a potentially important source of sperm whale DNA is material

in museum collections, e.g., teeth (cf. CARP/FP/2 and see

Item 10.9, below).

5.6 Historical Evidence

Hypotheses on population structure can be informed

by spatial discontinuities among concentrations of sperm

whales (“grounds”) where the species was observed or

hunted in the past (CARP/PS&M/3). A weakness of making

definitive inferences about population boundaries from such

evidence, however, is that sperm whales clearly move between grounds (e.g., photo-identified individuals from the

Galápagos were later seen in the Gulf of California; CARP/

FP/8). Differences in catch or sighting rates between regions can be interpreted as suggesting incomplete mixing,

and therefore contribute to hypotheses that can be tested

using other, more nearly definitive markers (e.g., genetics).

The temporal scales of available catch or sighting rate

datasets range from about five to 50 years, and large

amounts of such data are available for some areas and periods (e.g., Bannister et al. 1981; Hope and Whitehead 1991).

5.7 Other

Chemical analysis of trace elements in teeth might be

used for retrospective inference of habitat use. Such an

analysis may elucidate temporal patterns of movement between high- and low-latitude feeding grounds. An advantage of this approach is that it can be conducted using

archived material. Isotopic analysis of blubber, skin, or teeth

may provide insights into dietary preferences and, in turn,

population structure.

Best called attention to the possible use of differences

in breeding season to distinguish sperm whale stocks

(Tormosov et al. 2003).

6. ABUNDANCE AND DISTRIBUTION

6.1 Whaling Records

The geographic location of whaling can provide basic,

albeit potentially biased, information on spatial distribution

patterns. For example, Bannister summarized CARP/HI/3,

in which he attempted to characterize the 19th century sperm

whaling grounds as identified and described in the literature. Relying principally on the works of five major authors

(Beale, Wilkes, Scammon, Clark, and Townsend), he identified 64 locations worldwide: 17 each in the North Atlantic

and South Pacific and ten each in the South Atlantic, North

Pacific, and Indian Ocean. Relatively few of these were “mixed

grounds” where other whale species were also regularly
Page 7

hunted. Josephson and Smith illustrated the location of

these grounds in CARP/HI/6.

Year-round grounds were mainly in the tropical belt

between 30oS and 30oN whereas those south of 25oS or north

of 25oN were visited primarily in summer. While American

whalers dominated the industry, the British and French fleets

were also prominent for at least a few decades, and there

were some differences in the grounds used by American

and British whalers.

In discussion, Bannister confirmed that the Mediterranean Sea was not a major whaling ground, at least not for

the American fishery. It is also of interest that some areas

where sperm whales are present in relatively large numbers

today (e.g., the lee shores of Tasmania and Kangaroo Island, Australia; the northern coast of Chile; waters southeast of Sri Lanka) were not always identified as whaling

grounds. Bannister observed that problems inherent using

sailing vessels, e.g., the need to avoid lee shores, could

help explain at least some of what appear to be anomalies of

this kind.

Smith and Josephson described the distribution of 20th

century whaling activity in CARP/HI/15, noting that whaling was generally distributed more poleward, with relatively

little overlap with 19th century whaling grounds except in

the western North Pacific. The shifts in the grounds in the

19th century and the differences in the grounds used in the

20th century make it difficult to draw inferences about distribution patterns, especially over time and in areas where

whalers did not operate.

Changes in catch and sighting rates in the 19th century

suggest marked changes in abundance over decades on

the Japan Ground in the western North Pacific (Bannister et

al. 1981) and around the Galápagos in the eastern Pacific

(Hope and Whitehead 1991). Bannister et al.’s data were

used to estimate pre-whaling abundance of sperm whales

on the Japan Ground (Tillman and Breiwick 1983), although

the lack of clarity about population structure made it unclear whether the analysis should have taken into account

whaling results from other regions where this same whale

population might have been hunted (Smith and Reeves 2003).

In the 20th century, studies of sperm whales by the IWC

Scientific Committee also considered decreases in the numbers of whales caught per unit of effort (CPUE), although

the rapid evolution of whaling equipment and techniques

as well as the mixed-species character of many operations

often confounded the interpretation of such change (see

Appendix 5).

6.2 Genetic Diversity

Methods of estimating population size before whaling

that do not rely on catch data could be useful, especially

where the catch history and population models have large

uncertainty. The potential for using genetic diversity to

estimate historical population size (e.g., Roman and Palumbi

2003) was discussed within the IWC Scientific Committee

in 2004 (IWC 2005). The low mtDNA genetic diversity in

sperm whales represents a different situation than that of

the humpback whale, fin whale, and common minke whale

considered by Roman and Palumbi (2003). Given the low

mtDNA genetic diversity observed in sperm whales, direct

application of the Roman and Palumbi approach would be

problematic, and indeed it has not been applied to sperm

whale populations. However, Lyrholm et al. (1996) used a

novel genetic method, quite different from that of Roman

and Palumbi, to estimate time since common ancestry and

explain the low mtDNA genetic diversity in sperm whales.

The IWC Scientific Committee’s critique of Roman and

Palumbi’s paper (IWC 2005) stated, “A key concern regarding the use and interpretation of genetic-based estimates of

historic abundance is that these cannot be assigned to a

point in time narrow enough to assure that the estimates

apply to the time period just prior to the onset of whaling

that has been the reference point for management....” A

number of additional sampling, molecular, and analytical

biases and uncertainties require further investigation, as

outlined in the Scientific Committee’s report. Uncertainties

include the effect of unsampled populations on estimated

genetic diversity, the bias due to deviations from mutationdrift equilibrium, the ratio of effective population size to

survey population size, the mode and rate of changes in

mtDNA control regions, the genetic diversity in nuclear

loci, and methods of determining statistical reliability. Substantial further work would need to be completed before

genetically derived abundance estimates for sperm whales

could be deemed useful for assessment purposes.

6.3 Sightings and Acoustics Surveys, Including

 Dive Cycle

Gillespie introduced CARP/A&D/1, which reviewed and

compared acoustic methods of assessing sperm whale abundance. There are three basic types of surveys that incorporate an acoustic component: the “Cartwheels” method, “Distance”-type line-transect methods, and the “hybrid” method.

The Cartwheels method involves sampling at discrete stations along a transect and uses a statistical approach developed by Hiby and Lovell (1989) to estimate detection

range based on numbers of whales in 45o sectors at each

station. Its advantages are that individuals do not have to

be tracked for extended periods and that it only requires

point sampling. Among its disadvantages are that it requires

relatively large samples to narrow confidence limits for estimation of effective detection range, and it only works robustly when the separation between sampling stations is

50-130% of the detection range, thus requiring some prior

knowledge of detection range to ensure this. Bias in abundance estimates derived from the Cartwheels method will

be directly proportional to any bias in estimates of the proportion of time spent vocalizing. Distance-type line-transect

methods can be used effectively in areas, such as the Southern Ocean (Leaper et al. 2000), where densities are relatively
Page 8

low and individuals are separated by at least a few hundred

meters. They require the ability to track individuals or small

groups long enough to establish their positions by intersecting bearings from many points along the trackline. Hybrid surveys use acoustic detection to locate groups and

then require the vessel to close on them to obtain visual

estimates of group size.

Barlow and Taylor (2005) applied the hybrid method for

an extensive survey of the northeastern temperate Pacific,

resulting in an estimate of 20,000-30,000 sperm whales in

the study area. In presenting the paper, Barlow noted that

slow clicks were detected at ranges up to 37km whereas

usual sperm whale clicks were typically heard at less than

9km. In a separate study (Barlow and Rankin 2004) independent teams of observers searched for sperm whales visually and acoustically during surveys in the eastern tropical

Pacific. The percentages of missed groups on the trackline

were 38% for visual and 21% for acoustic. Assuming that

the two methods are independent, the percentage missed

by both teams was 8%. Although acoustic detection methods greatly reduced the fraction of missed animals, they

cannot reliably estimate group sizes and some groups are

still missed. Therefore, the authors recommended that a

hybrid approach be used for sperm whale surveys.

Most of the “groups” (= aggregations) included in the

study of Barlow and Taylor (in press) consisted of asynchronously diving “clusters,” which they defined as subgroups of 2-10 whales in close proximity to one another.

Such clusters were often spread over several square kilometers. Typically, the vessel would spend 90 minutes in the

area, with at least five observers maintaining a 360o watch,

before deciding on a final group size estimate. According to

Barlow, group size estimates made 10 minutes following initial detection were about half those made after the 90-minute

closing mode watch. During workshop discussion, it was

noted that in some circumstances (e.g., off Peru), clusters

of whales can be so numerous and geographically extensive that it leads to “system overload” on the part of survey

observers.

The sperm whale’s proclivity for deep, prolonged diving has generated concerns about availability bias (g(0)).

Those concerns are summarized below:

6.3.1 Visual

Better methods of estimating g(0), the probability of

detecting sperm whales on the trackline in visual linetransect surveys, are needed both to improve future density and abundance estimates and to “correct” the results

of past surveys. Whitehead (2002) used a single estimate of

g(0) to correct for missed animals for a wide variety of survey types in a wide variety of habitats. Better estimates of

density and abundance from past surveys could be obtained if g(0) estimates were more specific to the survey

method, region, and average group size.

Simultaneous use of towed hydrophones is likely to be

the best approach to improve g(0) estimates for visual

sightings surveys, as it is probably the only way to deal

adequately with the problem of estimating g(0) for groups

of asynchronously diving individuals. Estimates of g(0) can

also be derived from dive data for visual survey methods

that are based only on detecting individuals (e.g., cue counting). The usual methods of estimating g(0) using two independent teams of visual observers on ship surveys are not

likely to be effective for sperm whales because they only

account for perception bias (from animals that surface within

the visual range of observers but are not seen) and do not

include the likely greater contribution from availability bias

(from animals that are submerged and not available to be

seen).

6.3.2 Acoustic

Simultaneous use of visual and acoustic survey methods is also an effective way to estimate g(0) for acoustic

surveys, particularly those that treat groups as the units of

observation. Acoustic methods based on detection of individuals can be corrected using information on dive times

and surface times. Information on long periods of acoustic

silence (“resting” or “sleeping” behavior) is also important

for developing correction factors for acoustic surveys.

Whitehead pointed out that, in his experience, sperm whales

form spatially tighter groups in the Pacific than in the Atlantic. If this is true more generally, acoustic methods that

depend on detection of individuals might be more effective

in the Atlantic and methods based on detection of groups

might be more effective in the Pacific.

6.3.3 Group vs. Individual Detections

It is important to appreciate that in the line-transect

method described in CARP/A&D/1, the units of detection

are individual animals (albeit individuals that are aggregated)

while for the hybrid methods described by Barlow and Taylor (in press), the units of detection are groups. Detailed

information on vocal behavior, which can be obtained from

long recordings made while following individuals (“focal

follows”, e.g., see CARP/FP/1; Drouot et al. 2004a), may be

useful in calculating a value of g(0) for individuals in the

Distance-type method, although very detailed data – at the

level of the time of each click – may be required to model

this for different detection scenarios. It is unlikely that such

data can provide a realistic g(0) for “group” detection. This

will depend, however, on a host of factors, including spatial

distribution of the group, the precise definition of “group,”

and the degree of synchronicity of vocal behavior of individuals within the group. Further, it may be the vocal output of a small number of animals that determines a group’s

detection probability. Barlow noted (and see Barlow and
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Taylor in press) that in North Pacific surveys, aggregations

typically were not detected by the vocal output of most of

their members but, rather, by the characteristic calls

(“clangs” or “slow clicks”) of mature males within them.

6.3.3.1 Cost and Equipment

An advantage of passive acoustic monitoring is that it

can reduce survey costs by allowing the use of either small,

relatively inexpensive vessels (such as motor sailers) which,

because of their small size and hull shape, are often ideal

acoustic monitoring vessels, or platforms of opportunity.

In several instances, simple towed arrays and semi-automated analysis and recording systems have been used by

small teams of one or two researchers to conduct largescale quantitative acoustic surveys, incurring little or no

additional vessel costs. Oceanographic research vessels,

which often follow a predetermined survey design and collect useful ancillary oceanographic data, have proven to be

particularly suitable platforms. The hydrophone arrays used

for both the small-vessel surveys and the platform-of-opportunity surveys were very simple. Most, in fact, were less

sophisticated than the array described by Leaper et al. (1992).

Simple, low-cost equipment was appropriate for those early

trials and remains so for surveys from low-cost platforms or

platforms of opportunity. However, for dedicated surveys,

investment in larger two- or three-dimensional arrays offers

opportunities for greater spatial resolution. The continuing

advances in acoustic digital processing and the development of more powerful analysis software should make the

real-time analysis of data from such arrays feasible and affordable. In addition, groups such as the Centre for Research into Ecological and Environmental Modelling at the

University of St. Andrews, UK, are working on improved

analysis methods tailored to acoustic survey capabilities

and limitations.

6.3.3.2 Click Rate and Time Spent Vocalizing

Dawson summarized his experience in studying click

rate and the proportion of time individual sperm whales

spend silent (CARP/FP/1). For acoustic surveys, it is important to know what proportion of time whales spend vocalizing. For approaches based on click counting, it is important to know usual click rate. Usual click rates measured

over complete dive cycles of photographically identified

individuals at Kaikoura, NZ, showed that five-minute averages of mean usual click rate did not differ significantly

within dives, among dives of the same whale, or among

whales (Douglas 2000). On average, individual sperm whales

at Kaikoura spent 60% of their time usual clicking in winter

and in summer. There was no evidence that whale identity

or stage of the dive recorded affects significantly the percentage of time spent usual clicking.

For acoustic surveys at Kaikoura, it is probably reasonable to assume that the probability of detection on the

trackline is unity – at least for foraging individuals. This is

because silent individuals generally recommence clicking

while the ship is still within acoustic range. For example, the

dive cycle generally lasts about 54 minutes, and the longest

average continuous period of silence is around 14 minutes.

During 14 minutes, an acoustic survey vessel traveling at 8

knots will travel less than 2nmi, far less than the typical

range over which usual clicks are detectable.

6.3.3.3 Cue Counting

Abundance estimates for the central and eastern North

Atlantic from the NASS-2001 survey are based on a cuecount-transect method that corrects for availability bias

(Gunnlaugsson et al. 2002). This method critically relies on

information about the dive cycle (frequency of dives and

proportion of time spent at the surface between dives), and

it is preferable that the dive data come from the area being

surveyed. It is anticipated that the same method will be

used to analyze data from the NASS-2007 survey

(Gunnlaugsson, pers. comm.). The method has only been

applied in high-latitude regions of the North Atlantic where

most sperm whales are solitary males. It is uncertain whether

it would be practical in areas where whales occur in large

groups.

6.4 Individual Identification

Mark-recapture estimates (using photo-identification)

are available for sperm whales only in a few local areas

(Leaper et al. 2003). Assumptions concerning random sampling, population closure, and immigration/emigration apply to sperm whales as they do to other cetacean populations, although particular complications may arise from “social organization within mixed groups” of sperm whales.

Additional discussion of mark-recapture estimation appears

under Items 5.2 and 5.5 and in Annex 5.

7. LIFE HISTORY (CARP/LH)

7.1 Age Determination

Bannister drew attention to a study of growth layer

groups (GLGs) in 92 teeth collected from three sperm whale

strandings on the Tasmanian coast (Evans et al. 2002). The

large inter-reader variability suggested that age estimates

based on GLG counts in sperm whales are subjective and

can only be regarded as relative. Photographs increased

definition of growth structures and decreased variation

between counts. High-quality photographs should be used

to verify GLG counts with other readers, resulting in “con-
Page 10

sensus counts,” ensuring interpretation of the same structures and confidence in comparing GLG counts.

7.2 Vital Rates

In introducing a review of sperm whale vital rates

(CARP/LH/1), Best pointed out that these were an important component of past management attempts to set catch

limits. Their current significance, however, at least in the

context of this workshop, is probably limited to providing

input to models used to explore the effects of past whaling

on population trajectories and estimate initial population

sizes.

Twentieth-century sperm whaling featured the differential exploitation of males because of their larger size (and

proximity to summer whaling grounds for baleen whales in

higher latitudes). The effective sex ratio (or the proportions

of mature animals of each sex needed to maintain the fertilization rate) was therefore a major issue in assessments of

sperm whales. In the absence of information on the mating

system, the Scientific Committee of the IWC used a model

based essentially on the premise that males tend to join

groups of females that then travel together for extended

periods. Thus, based on observed group sizes, the Committee assumed that 2 mature (at least 25 years old) males were

needed per 15 mature females in the population, and that if

the ratio fell below that level, the pregnancy rate would

decline accordingly. To test whether greater relative male

depletion indeed resulted in reduced female breeding success, the Committee examined the observed pregnancy rate

in the catch. Results were equivocal, with observed declines possibly confounded by temporal shifts in the whaling grounds or in the degree of selection against lactating

females. Also, the male depletion models that were used

tended to fail to match the observed trends in pregnancy

rate, either qualitatively or quantitatively. Recent observations of living sperm whales suggest that large males associate only very briefly with a school of mature females during the breeding season. In Best’s view, this observation

suggests that the Committee’s analyses were biased toward under-estimating resilience. Whitehead pointed out

that results from different kinds of analysis suggest that

the breeding success of male sperm whales is highly skewed

(see Whitehead 2003:282-83) and thus that pregnancy rates

are not resilient to changes in the abundance of large males.

Identification of socially mature males as individuals at

least 25 years old was based on a rapid increase in testis

growth and density of spermatozoa in the seminal fluid at

this age, as well as observations of the size of males accompanying females in the breeding season. However, physiological maturity (the stage at which spermatozoa are first

present in the testes) occurs much earlier, even in males as

young as 10-12 years. Moreover, there is a secondary acceleration in growth in body length at around 18-20 years of

age, possibly associated with the commencement of migrations to higher latitudes than those normally visited by

females. Whether any of these younger males manage to

participate successfully in breeding is unknown, but some

investigators consider it possible that they could do so in

the absence of competition from larger males (Best 1979).

Modeling the effects of whaling also requires estimates

of natural mortality rate. These were obtained in the past

from the age composition of the catch, and were therefore

likely confounded to some degree by fishing mortality. Thus,

while population theory would suggest that male sperm

whales should have higher natural mortality rates than females, and that natural mortality should increase in older

mature individuals of both sexes, the appearance of such

features in the age-composition data could equally be attributed to the effects of exploitation. In spite of these uncertainties, the IWC Scientific Committee adopted a higher

natural mortality rate for males than females. Juvenile mortality has remained unmeasured in either sex.

7.3 Social Structure

Mesnick presented CARP/PS&M/1, CARP/PS&M/2,

and CARP/LH/4 on behalf of herself and her various coauthors. All three papers are relevant to this agenda item as

well as to Item 5 (Population Structure and Movements),

above. Sperm whales have a complex social structure. The

observed “group” of females and immature whales is a temporary association between more stable social “units.”

Breeding males rove between female groups, but important

elements of the mating system remain unknown. Male-biased exploitation and the possible disturbance of the groups

of females and immature whales by whaling may have lowered the fecundity of surviving females, although evidence

and mechanisms for such reduction have not been clearly

identified. The social structure and mating system of sperm

whales are being studied principally using photo-identification and genetic analyses. These types of studies are

augmented by studies of vocalizations, observed behavior,

and information from short- and long-term tags, and through

inferences from other aspects of sperm whale biology. Genetic research is under rapid development. Research on

paternity and the relationship between fecundity and social integrity is particularly important.

At present, no genetic evidence of a strictly or largely

matrilineal unit or group of sperm whales is available. Rather,

genetic results suggest that groups of female and immature

sperm whales generally contain more than one matriline (a

matriline being a set of animals with the same oldest living

female ancestor), as indicated by the presence of multiple

mtDNA haploytpes. Both “groups” and “units” contain

clusters of closely related animals, but some individuals

have no close relations. These results are consistent across

50+ groups sampled at sea and in strandings in four different ocean basins (Richard et al. 1996; Christal et al.1998;

Bond1999; Lyrholm et al. 1999; Mesnick 2001; Mesnick et

al. 2003; Engelhaupt 2004). The view of female sperm whale

social structure that is emerging is one of kith (close, but
Page 11

not genetically related companions) and kin. Observations

of groups in areas without a significant modern whaling

history are currently being collected in the western Atlantic

(Whitehead, pers. comm.) and may be particularly valuable

in addressing whether the non-matrilineal structure is an

artifact of removals by commercial whaling.

There was considerable discussion of whether the low

observed proportions of calves (about 1% in the Galápagos;

Whitehead et al. 1997) are indicative of low calving rates,

and if they are, whether this is an intrinsic and “normal”

feature of the species or instead reflective of the differential

depletion of large males by commercial whaling that ended

more than 20 years ago. An alternative explanation would

be that low observed proportions of calves is an expression

of the extreme environmental variability of the region. The

observed proportions of calves in various low-latitude areas seem to differ markedly today, suggesting that rates of

increase can vary according to population history and/or

other factors. The workshop recognized that some inconsistencies in the available data could not easily be reconciled, but concluded that it would be useful for field researchers in different geographic areas to compare their

observations of proportions of calves. In view of the difficulties of detecting calves (or identifying individuals as

calves) at sea, hormonal sampling of females from biopsies

might be worth considering as an approach for estimating

calf production (pending a demonstration of feasibility).

Stranded groups of subadult males have been found to

be composed predominantly of unrelated individuals, although there were cases of half-siblings within each of the

groups (Bond 1999; Engelhaupt 2004).

Kato introduced CARP/LH/2, which examined the ageand body-length structure of a sperm whale school composed of 14 males that stranded on the Ohura coast,

Kagoshima, Japan, on 22 January 2002. The authors succeeded in obtaining body lengths for all animals and ages

for 12 of the 14. Although one exceptionally large male (15.5

m, 41 yr) was involved, the lengths (mean 12.81, range 12.1

– 13.7 m) and ages of the remaining animals were consistent

with those for medium-sized bachelors as defined by Best

(1979). Thus, these data were interpreted as supporting the

existence and definition of a male social unit. The authors

gave two alternate interpretations for the presence of the

large male: either this animal was socially still immature, or

large males do not always segregate permanently from other

social units.

Dawson summarized the results of his work on body

size distribution of male sperm whales in the Kaikoura area

of New Zealand (CARP/FP/1). Norris and Harvey (1972)

proposed that multiple pulses present in clicks result from

reflections within the head, and thus that inter-pulse interval (IPI) is an indicator of head length, and by extrapolation,

total body length. While several previous studies have generated acoustic estimates of whale length, only one (Gordon 1990) was validated by independent measures of length

(for 11 individuals). Research at Kaikoura, NZ, on individually identified, photogrammetrically measured whales

showed that, measured over short periods within the same

dives, IPIs were highly stable within individuals. Further,

the relationship between IPI and photogrammetrically measured length was non-linear (a second-order polynomial

had a highly significant fit; Rhinelander and Dawson 2004).

Most individuals showed significant increases in IPIs over

several years, suggesting growth.

Dawson considered that IPIs provide more precise estimates than photogrammetry and thus are more suitable for

sampling the size, age, and sex distribution of whales in a

given area or group. He recognized, however, that more IPI

data and more independent photogrammetric data will be

needed to further develop the relationship. Other participants cited the difficulty of applying Dawson’s methods to

sperm whales in areas where they occur in large groups. It

was agreed that there should be a standard procedure for

recording IPIs that takes account of the animal’s orientation with respect to the receiver. The small but measurable

effects of pressure and temperature need to be incorporated and accounted for. Also, Best called attention to the

possibility that post-mortem stretching may help explain

the difficulty of reconciling carcass lengths measured on

whale processing platforms with lengths derived from photographs of living animals.

8. POPULATION ECOLOGY

8.1 Feeding

In introducing his review of sperm whale feeding Best

noted that feeding success might be a key factor in interpreting sperm whale movements and population dynamics.

The nature of sperm whale food has been fairly well established through the examination of stomach contents and

(more recently) the collection of feces at sea (CARP/PE/1).

Both methods have various biases, many of them in common. In the case of stomach contents, some bias can be

circumvented through the use of prey items with flesh still

attached. Fecal sampling has the additional problem of the

differential sinking rates of beaks of different sizes. Most

studies to date have demonstrated the predominance of

cephalopods, especially mesopelagic and bathypelagic

squids, in the diet, although fish are of considerable importance in some areas. There is some evidence of prey partitioning by sex (and in males by size), with larger males tending to feed on larger species of squid and to take larger

individuals of a particular species than females and small

males. Also, males in general feed more frequently on benthic

fishes and crabs.

Rates of feeding have historically been examined

through the incidence of fresh remains in the stomach, but

analyses have largely been confined to estimates of diurnal

or intra-annual variation, rather than inter-annual trends.

Data on blubber thickness have been used as a proxy for

feeding success, but such data are sensitive to the measurement techniques employed. More recently, defecation
Page 12

rates in living animals have been used as a measure of feeding success. Differential feeding rates between larger males

and females and/or smaller males have been found in a number of studies, using data on both stomach contents and

defecation. It has also been suggested that large males are

out-competed by females when they occur sympatrically.

There was some disagreement among participants concerning the value, and indeed the feasibility, of using defecation as an index of feeding success or rate. Jaquet pointed

out that detection of feces on the surface can be influenced

by lighting conditions and height of observation platform.

Madsen stated that a strict study protocol is needed to

avoid startling the whales and inadvertently “forcing” them

to defecate. Drouot noted that sperm whales in the Mediterranean are rarely observed to defecate. Moreover, it is

difficult to see how to calibrate defecation to feeding rates,

even if it were possible to observe whales constantly over

a full feeding cycle, and if there were no heterogeneity in

digestibility and pass-through rates of different prey types.

Bando summarized the analyses of stomach contents

from 28 sperm whales taken from May to September under

the 2000-2003 JARPN II program in the western North Pacific (CARP/PE/03). Thirty-two prey species were identified, consisting of 28 squids, one octopus, and three fishes.

Weight of stomach contents was measured for each individual and mean weight was ca. 0.2-0.5% of total body weight

in each subarea. Intestine contents were sampled from some

of the whales. Numerous beaks were found in the large

intestine. Species identification of these beaks and comparisons with stomach contents are ongoing. Bando expressed the view that these types of analyses are important

for future elucidation of feeding ecology of sperm whales

and that they can contribute to improvement of non-lethal

sampling methods, such as fecal sampling. In response to a

question, Ohsumi stated that these data coming from animals killed in offshore waters supplement previous studies

of stomach contents from animals killed in coastal waters.

Madsen suggested that oxygen uptake and biomass

turnover might be estimated from ventilation rates (obtained

from D-tags) and that this could provide a more accurate

assessment of the sperm whale’s role in the ecosystem than

simply additional data on stomach contents from killed

whales. In fact, understanding the species’ role in the ecosystem requires information on both metabolic needs and

what is consumed.

Drouot presented CARP/PE/2 on investigations of

sperm whale feeding in the Mediterranean. In the past,

feeding success has been assessed by measuring the fatness or blubber thickness of stranded animals (i.e., average

success over a few weeks or months) and by analyzing

stomach contents (i.e., evidence of feeding over a few hours

prior to death). Another method that has been used recently

is to count “creaks,” which are vocalizations (increased

click rate of up to 220/sec, persisting for 10-25sec, followed

by silence) thought to be produced by sperm whales investigating targets at close range, and therefore indicative of

feeding attempts (cf. Miller et al. 2004a). This method was

applied in the northern Mediterranean, where single sperm

whales made an average of 25 creaks per dive (Drouot et al.

2004b). However, the method is difficult to apply when several whales are diving within range of the hydrophone, as it

becomes difficult to discriminate the creaks of individual

whales by ear. Further methodological development is

needed before feeding attempts can be reliably detected

and counted in such conditions. Other issues that need to

be resolved are how to enumerate the number of prey items

taken per creak (e.g., proportion of missed prey, catches of

single or multiple prey) and the meaning of pauses in the

click sequence (e.g., visual approaches of bioluminescent

prey?). Timing of the first creak of a dive (consistently

about 6 minutes following flukes-up in the Mediterranean study by Drouot and Gannier) is believed to provide a rough estimate of the depth of the feeding layer.

In addition to providing insights on sperm whale feeding

ecology, the creak rate and the foraging depth may be

useful parameters for helping to assess the effects of

anthropogenic disturbances.

In discussion, participants cited the difficulty of distinguishing creaks from interruptions in clicking (pauses) that

may be unrelated to foraging (cf. Jaquet et al. 2001). Also,

there is the problem of knowing whether any given foraging attempt was or was not successful (cf. Miller et al. 2004a).

There is very high within-region variability in creak rates.

Generally, it was agreed that analyses of creak rates to assess foraging patterns, while promising, are problematic in

some respects and need further development.

Other possible approaches to assess foraging success

might include ultrasonic measurement of blubber thickness

(cf. Moore et al. 2001) and using high-resolution archival

tags (so-called D-tags) to infer blubber content from buoyancy and gliding patterns during ascent and descent (cf.

Miller et al. 2004b).

8.2 Diving Physiology

During an average dive, a sperm whale spends about

45min at depth and about 10min at the surface recovering.

Scaling from the Weddell seal, it has been estimated that a

45min dive is within a sperm whale’s aerobic dive limit. Miller

inferred, based on D-tag data, that female sperm whales

approach their predicted aerobic diving limits more often

than males. However, Whitehead expressed his impression

that in a given area, females and males seem to dive approximately for the same length of time, while on a global scale,

males exhibit more variable diving behavior than females,

the latter being relatively stereotyped in this regard.

Attention was drawn to the recent paper by Moore and

Early (2004) where they document progressive bone damage in sperm whales, which they speculate could be related

to trauma from nitrogen sickness (the bends). This hypothesis, if true (but see Rothschild [2005] and Moore and Early

[2005]), indicates that sperm whales pay a physiological

price for their deep-diving behavior.
Page 13

Diving physiology is relevant to estimation of g(0) (see

Item 6.3), and therefore actual dive times, when measured,

should be published and, if at all possible, stratified by sex.

In relation to this point, Whitehead noted that the percentage of time spent socializing by sperm whales differs considerably by area (e.g., Caribbean vs. tropical Pacific), and

that because much of this behavior is at the surface, this

could have a large effect on g(0).

Thode presented CARP/A&D/2 (and see Thode et al.

2002; Thode 2004), which was relevant to a number of agenda

items involving the underwater acoustic tracking of sperm

whales. Sperm whale clicks generate enough energy to reverberate, or echo, off the ocean surface and bottom. Under

certain circumstances, these echoes can be used to track a

sperm whale in range and depth using a single hydrophone

deployed from the surface. This technique has been used

to measure sperm whale dive profiles and foraging depths

in the Gulf of Alaska and Mexico. The foraging behavior of

sperm whales around longlines in Alaska has also been

investigated. If a second hydrophone can be deployed

with sufficient horizontal separation, a 3-dimensional dive

track can be derived under more general circumstances,

because then only a single surface-reflected echo is needed.

Automated systems using this method are currently being

developed as part of a study in the northern Gulf of Mexico

(Sperm Whale Seismic Study, Texas A&M), where potential

correlations are being investigated between sperm whale

foraging and the presence of prey concentrations signaled

by acoustic backscattering. These techniques are currently

being incorporated into standard acoustic tracking software.

9. HUMAN INTERACTIONS

9.1 20th Century Whaling

Smith drew attention to Allison and Smith (2004), which

described and classified whaling operations around the

world, drawing on Reeves and Smith (in press). Five types

of operation were responsible for most of the sperm whale

hunting in the 20th century. Of these, the most important

were Norwegian-style land stations and factory ships. The

magnitude of whaling in the 20th century is remarkably well

known, although an integrated database representing the

complete catch data has only recently been assembled.

Catch records for many whaling operations were reported

to and assembled by the Bureau of International Whaling

Statistics (BIWS) between 1930 and 1986, and reported to

the IWC subsequently. However, catches for some whaling

operations were not reported to, or otherwise did not come

to the attention of, either of these bodies.

The 20th century catch data have been assembled in a

single database, seasonally and by expedition or land station for the entire century. The database shows that 20th

century catches are relatively well documented. It provides

a better understanding of the completeness and reliability

of some data sources, and it has resulted in improved allocation of catches to species and area. In the process of

assembling the database, whaling operations with substantial remaining uncertainties have been identified, and this

affords guidance on where additional archival research

would be most valuable.

Reports of total catches are available at quite detailed

levels (Allison and Smith 2004: their Table 2). Decadal summaries by ocean basin, nation, and type of operation reveal

the major whaling operations and how catches shifted over

the century (Allison and Smith 2004: their Table 3.)

In addition to the total catch data, information has been

reported on individual whales taken, including location, sex,

and length, in some cases with additional biological observations. Reports on individual whales are available for a

large fraction of the total whales caught, and include locations. These data show that 20th century catches were generally at higher latitudes than pre-20th century catches, and

there was limited spatial overlap with the earlier whaling

grounds (CARP/HI/15).

A number of whaling operations have been identified

for which submitted data were either incomplete or falsified

(e.g., Zemsky et al. 1995; Kasuya 1999; Yablokov and

Zemsky 2000). While these data have been improved in

many cases, major uncertainties remain concerning catches

of sperm whales in the North Pacific by Soviet pelagic operations and some Japanese shore stations. Because of the

likely degree of falsification, there is a need to address these

uncertainties in order to determine the biological impact of

sperm whaling in this ocean basin. One approach that has

proven useful is to search for archival data that were collected during whaling operations but were not reported. In

the absence of such archival material, various statistical

approaches exist that would allow estimation of missing

catches from similar whaling operations where more nearly

complete data are available. Such approaches are currently

being applied to Antarctic catch data and should be applied

to North Pacific data. Kasuya (2003) outlined an approach

for dealing with some of the Soviet and Japanese records

and called for an expansion of coverage to include additional geographic and seasonal strata in the North Pacific.

There was no known falsification of sperm whale catches

by modern whaling in the North Atlantic.

In both the North Pacific and the Southern Hemisphere,

sperm whale catches were routinely under-reported by the

USSR (Soviet Union) beginning in about 1948 and continuing until the early 1970s when the International Observer

Scheme came into effect (Yablokov et al. 1998; Brownell et

al. 2000). In the North Pacific, true catch data are available

for only two floating factory fleets: the Dalnij Vostok and

the Vladivostock. Catches were misreported both in total

and by sex, with the overall true catch total for these two

fleets being 106,053 (reported = 86,741). Totals for the two

fleets by sex were as follows: males 73,173 (reported 72,532),

females 32,880 (reported 14,209). True catch data are not

available for three other floating factory fleets. However,

using correction factors derived from the Dalnij Vostok
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and Vladivostock data, Brownell et al. (2000) estimated total Soviet North Pacific takes for 1949-71 at ca. 180,000 sperm

whales. If one adds to this the 1972-79 total catch (32,338),

the grand total of Soviet sperm whale catches in the North

Pacific (known + estimated, 1949-79) is approximately

212,338 whales. Also in the North Pacific, the reliability of

Japanese catch statistics is in doubt, especially for postWorld War II operations (Kasuya 1999).

Southern Hemisphere catch records have been largely

rectified. The total true Soviet catch of sperm whales in the

Southern Hemisphere was 89,493 (reported = 74,834;

Yablokov et al. 1998, Clapham and Baker 2002). The total

estimated 20th century catch for the Southern Hemisphere

(all nations, including the revised Soviet data) was estimated by Clapham and Baker (2002) at 395,000 sperm whales.

9.2 Pre-20th Century Whaling

In a previous workshop (July 2002), a detailed research

program was outlined to improve understanding of the effects of whaling on sperm whale populations worldwide

and on regional scales (Smith and Reeves 2003). The emphasis was on refinement of catch history for pre-modern

(“open-boat”) sperm whaling. Smith provided an overview

of progress since 2002 on that research agenda (CARP/HI/

5).

One area of progress was improved estimation of openboat removals on a global basis from aggregate and voyage-based sperm oil returns, following earlier work by Best

(1983). Improved estimates for the 19th century and new

estimates for the 18th century are being developed by Best

(CARP/HI/16 and CARP/HI/17). For the 19th century, the

overall approach had been to compile sperm oil production

figures from the US and other whaling operations, either

using declared landings from that fishery (US, Britain,

France) or oil imported into the UK from other fisheries

(Germany, Australia, New Zealand, Chile, etc.). Where possible, the latter imports were checked against declared exports from the nation concerned. A correction factor for

vessels lost was applied to the US production figures (and

will be applied to the British figures; Best, pers. comm.).

The adjusted production figures were then used as an index of the total catch, and were divided by a barrel-perwhale figure to obtain an estimate of the number of whales

processed. Where possible, barrel-per-whale figures were

used that were from that contemporary fishery. In the case

of the US fishery, such figures were obtained by dividing

the declared returns of a particular voyage, as listed by

Starbuck (1878) or Hegarty (1959), by the number of sperm

whales listed for the same voyage by Townsend (1935).

These yields were in turn stratified by vessel-type, as smaller

vessels (brigs, schooners, and sloops) tended to have lower

mean oil yields than larger vessels. For other nations, oil

yields were obtained either from information on the given

nation’s own fishery (e.g. France, Azores) or by analogy

with the US fishery (e.g. Britain). The total landed catch for

the 19th century (adjusted for vessel loss rates) was estimated to be 271,900 sperm whales, of which 69.1% were

taken by US whalers. At its peak (ca 1840), the fishery may

have been landing between 6,000 and 7,000 sperm whales

annually.

For the 18th century the overall approach was much the

same, but adequate series of production indices were only

available after 1762, and then often only as “train oil” without any indication as to type (whale or sperm). Some separation was attempted using whalebone (baleen) landings to

determine the proportion of whale oil, although the retention of whalebone seemed to be strongly affected by market forces. Production figures for the US from 1790 from

Starbuck (1878) were pro-rated upward to account for missing voyages (using Lund 2001). Adequate barrel yield per

whale data were only available from the French fishery, and

an average value from this source was applied to all production figures. The estimated total landed catch from 1762

to 1799 from the US, British, and French fisheries, combined

(adjusted for vessel loss rates), was 27,600 sperm whales,

of which 74% were taken by US whalers. The estimates

from both CARP/HI/16 and CARP/HI/17 refer to landed catch

only, and still need to be adjusted for whales struck and lost

that died and were not recovered.

Smith presented CARP/HI/1 in which he and his colleagues summarized other progress since the 2002 workshop. A “voyage database” contains summary information

for roughly 15,000 individual voyages by American whaling vessels. This includes information on rigging, announced destination, and amount of sperm oil (and other

products) obtained during the voyage. A second database

contains daily information from a sample of whaling logbooks, including numbers of whales sighted and taken, and

in some cases volumes of oil obtained from individual whales.

Pierce and Smith (CARP/HI/11) described the specific data

being extracted and the data entry program being used.

Smith and Josephson illustrated selected voyage tracklines

in CARP/HI/7, and illustrated the location of catches as

individual points and as numbers per area in CARP/HI/8.

Taken together, these two databases allow estimation

of total catches using two approaches. One is that used by

Best (CARP/HI/16 and CARP/HI/17) – volume of oil landed

divided by average volume of oil obtained from individual

whales. The second approach estimates the catch as the

product of the numbers of voyages and the average numbers of whales per voyage. CARP/HI/2 addressed the characteristics of these two approaches. The oil yield per animal

was most affected by latitude, as would be expected from

the known sex and size segregation, and the apparent differences in average oil yield per whale from vessels with

different rigging was not significant once latitude and year

had been accounted for. It is known that vessels with different rigging were used in different regions (e.g., Atlantic

versus Pacific), and likely in different latitudes, so assigning a single average yield per whale may be inappropriate.

Further, CARP/HI/2 demonstrated greater average numbers

of whales per voyage for the generally larger barks and
Page 15

ships than for the usually smaller schooners and brigs, as

well as higher average catches per voyage after 1875. The

authors plan to explore further the implications of using the

catch-per-voyage estimator for different time periods and

areas.

Smith’s presentation prompted a discussion of whether

sperm whales in different areas differ in body size (= oil

yield). No conclusion could be reached, but this is a question that deserves closer investigation through a variety of

methods. In response to a question as to whether spermaceti was ever registered separately from sperm oil, Chatwin

and Best said that the distinction was generally not made

except sometimes early in the fishery when “head matter”

was listed as such. There was also a brief discussion of

how large sperm whales could get. Best stated that yields in

excess of 100 barrels were not infrequently recorded (there

being 31 whales with this yield or greater in the Townsend

“abstracts”) and that a 100bbl sperm whale would be about

63 ft long.

Lund called attention to the availability of a collection

of ship manifests for New Bedford covering the years 1818-

1919, noting that a small sample examined by her had revealed a number of discrepancies with the product data in

Starbuck (1878). Further investigation of these manifests

subsequent to the workshop revealed that the discrepancies primarily occurred in the earlier years (Lund, pers.

comm.).

During discussion, attention was drawn to what has

been described as a paradox. Regional historical studies by

Bannister et al. (1981) and Hope and Whitehead (1991) appeared to confirm that whaling pressure in the 19th century

caused declines in sperm whale encounter rates on both

the Japan and Galápagos Grounds, yet this would imply

much smaller pre-exploitation whale numbers than are plausible, given the magnitude of the catches by the modern

whaling industry in the 20th century (for further elaboration, see Whitehead 1995). Among possible explanations

(from Smith and Reeves 2003) are that: (1) analyses of encounter rates have been confounded by changes in whale

behavior (i.e., they learned to avoid the whaling ships), (2)

catches by the open-boat fisheries have been greatly underestimated, or (3) environmental carrying capacity for

sperm whales increased substantially between the 19th and

early or mid-20th century.

9.3 Interactions with Fisheries and Shipping

9.3.1 Longline Depredation

Straley summarized CARP/HI/9, noting that there is

evidence of depredation by sperm whales on longline gear,

defined as observation of damaged or lost fish, reduction in

expected catch, or damaged hooks, from many locations in

the Southern Hemisphere, the Gulf of Alaska (see CARP/

HI/10), and the North Atlantic off Greenland and Newfoundland. Most observations have involved solitary or small

groups of male sperm whales. Target fishes have included

sablefish (Anoplopoma fimbria), grenadier, and Pacific halibut in the North Pacific, Greenland halibut (turbot) in the

North Atlantic, and Patagonian toothfish in the Southern

Ocean. In all reported instances, depredation has occurred

on fishing grounds that are also recognized as natural feeding grounds for sperm whales, and the authors of CARP/

HI/9 concluded that longlining has simply made it “easier”

for sperm whales to obtain their natural prey. A better understanding of the nature and magnitude of interactions

between sperm whales and longline fisheries will depend

on the systematic collection of data. In the toothfish fishery, explosives are used, at least to some extent, to deter

whales. Unfortunately, a large part of this fishery is illegal

and uncontrolled, which effectively precludes monitoring

and mitigation for that component.

9.3.2 Longline Depredation in Alaska

Straley summarized CARP/HI/10 on the longstanding

problem of sperm whale depredation on demersal longlines

in the Gulf of Alaska. Depredation on gear set for sablefish,

also called black cod or butterfish, has been occurring since

at least the mid-1970s when the phenomenon was first observed. The fishery, one of the most lucrative in Alaska,

was year-round until the early 1980s when fleet expansion

resulted in a regulatory shortening of the season. In 1995

individual fishing quotas were implemented, reducing overall effort with an 8 month open season.

In 2003 and 2004, the North Pacific Research Board

funded the first phase of a collaborative study between

fishermen, scientists, and managers to collect quantitative data on longline depredation. Off the port of Sitka, in

the eastern Gulf of Alaska, the shelf edge is 10-20nmi

offshore. This makes Sitka an ideal study base because,

within 2 hours of departure, a researcher in a fast boat

can be following fishing vessels hauling longline gear

off the shelf. The eventual goal is to develop deterrents

or changes in fishing practice that will reduce depredation and hence decrease the economic loss to fishermen.

Fishermen collect data on fishing activity and whale behavior, and they provide photographic documentation.

Also, they assist in the deployment of acoustic equipment (hydrophone arrays) on their longline anchoring

gear. The initial phase of the study has been successful

in finding sperm whales near fishing vessels and evaluating the magnitude of the depredation.

Results indicated that whales were present near the fishing vessels about a third of the time. Of those sets with

whales present during the haul, 65% had evidence of depredation. Depredation was determined by the presence of

shredded fish bodies or lips remaining on hooks. From 1 to

7 whales were found near the fishing vessels. Also, lone

sperm whales were observed to dive repeatedly along the

shelf edge with no vessel in close proximity. Preliminary

genetic results determined that the six whales biopsy-
Page 16

sampled in 2003 were all males. A total of 34 individual sperm

whales were photo-identified across both years.

The conflict between fishermen and sperm whales arises

from the spatial and temporal overlap in their efforts to take

advantage of the same resource. Fishing vessels may function as magnets for whales that would not otherwise associate with one another. This may create opportunities for

researchers to learn about feeding and social behavior, individual movements, and population structure. Mark-recapture methods can be used to estimate the number of whales

in the region. Future plans include (a) placing cameras on or

near longlines to discover how fish are removed from lines

and (b) expanding the acoustic component. This latter would

involve using a towed passive array for 3-dimensional tracking to estimate how far away a sperm whale can hear a

fishing vessel and how far away the vessel (fisherman) can

hear the whale.

In discussion, it was noted that although pots can be

used to catch at least some of the demersal target fish species,

longlines are currently the most common gear used . Thode

listed three basic approaches for addressing the depredation

problem: (1) not fishing in certain areas (avoidance), (2) active

deterrence, and (3) passive deterrence. The last of these may

involve reduction in acoustic cues (e.g., quieter winches) or

“flashing a mirror” (acoustically) back at the whale as it homes

in on its target. He cited rockfish bladders, which make the line

“light up” acoustically as it is being hauled, and bird activity

as among the cues that might attract whales. Mesnick pointed

out that one of the best strategies is to prevent the problem

from starting. She noted that in the past, Alaskan longliners

would spend 45 minutes hauling the line very loudly and then

effectively “chum” the whales and various scavengers as they

processed the catch.

Cornish called the workshop’s attention to the International Fisheries Observer Conference in Sydney, Australia,

in November 2004, and specifically to the pre-conference

workshop on “Developing Best Practices for the Collection

of Longline Data to Facilitate Research and Analysis to

Reduce Bycatch.” Although sperm whales do not appear to

be killed or injured often as a result of their interactions with

longline gear, it was clear that observers on longline vessels represent a potentially valuable resource for collecting

systematic data on sperm whales observed in the vicinity

of fishing operations. A data form developed by Straley in

collaboration with Alaskan fishermen provides a standard

format for documenting interactions with sperm whales.

Among the important elements to include are target species

of the fishery, bycaught species, presence of offal, where

whales occur in relation to the vessel and currents, and

behavior of the whales around the vessel.

9.3.3 Bycatch

Although it was not discussed in any detail, participants wished to record the fact that sperm whales are, like

other cetaceans, susceptible to entanglement in gillnets.

The frequency of entanglement has been noted as a particular problem in the Mediterranean Sea (Notarbartolo di

Sciara 1990) and along the west coast of South America

(Haase and Félix 1994).

9.3.4 Ship Strikes

Sperm whales are also susceptible to ship strikes (Laist

et al. 2001) although the frequency of collisions appears to

be low off North American coasts. Collision risk is regarded

as a more significant conservation concern for sperm whales

in the Mediterranean Sea and around the Canary Islands.

9.3.5 Competition with Fisheries

The neon flying squid (Ommastrephes bartrami), which

is one of the major target species for fisheries in Japan, was

found in the stomachs of sperm whales sampled during the

2000-2003 JARPN II surveys in the western North Pacific.

Preliminary estimates indicate that 800,000 tons of neon

flying squid are consumed by sperm whales, equivalent to

roughly eight times the total estimated catch of this species

by fisheries in the western North Pacific (Tamura et al. 2004;

CARP/PE/3). Ohsumi suggested that these estimates indicate the possibility of competition with fisheries.

The Gulf of California is another area where sperm whales

might feed on a commercially fished species of squid, in

this instance jumbo squid (Dosidicus gigas), which is a

major food source for sperm whales off Peru and Chile. A

pilot study of sperm whale diving behavior in relation to

squid distribution and behavior was conducted off Santa

Rosalia (Gulf of California) (CARP/FP/8). Five sperm whales

were tagged with satellite-linked time-depth recorders and

several large D. gigas were tagged with archival tags. Preliminary analyses showed that sperm whales spent most of

their time at depths of around 300m, but comparisons with

squid data have not yet been completed. This was the first

time that both sperm whales and their potential prey were

tagged simultaneously in the same area, and further research

is planned. See also Item 10.3.

Deep-sea fishing operations have often targeted species that are long-lived, slow-growing, and poorly known

(e.g., rockfish, Sebastodes), with predictable results of overexploitation and stock collapse. In some cases, fishes that

form part of the diet of sperm whales in some areas have

been fished more generally, potentially resulting in a perturbation to part of the food supply of sperm whales.

9.4 Environmental Issues

9.4.1 Contaminants

There is widespread and growing concern about the

effects of chemical contamination on high-order marine con-
Page 17

sumers, such as the sperm whale. This topic was not reviewed for the workshop or discussed in depth. However,

Godard and her colleagues with Ocean Alliance summarized their biopsy sampling program and their plans for conducting a variety of contaminant analyses (see Item 10.8,

below).

Godard presented a summary of Godard et al (2004),

which demonstrated in vitro cytochrome P450 1A1 induction in sperm whale tissues after exposure to ßNaphthoflavone. The study demonstrated a causal relationship between chemical exposure and CYP1A1 induction and therefore validated the use of CYP1A1 expression

in skin biopsies as a biomarker in sperm whales (and other

cetaceans).

9.4.2 Underwater Noise

Sperm whales are acoustically oriented animals. The

extent to which they use sound in all aspects of their lives is

still being elucidated, and new technologies such as archival telemetry are providing new insights in this area. One

indication of the importance of acoustics for this species is

the extraordinary investment in specialized energy-rich fats

and oils found in the spermaceti, junk, and other associated

bodies within the head. Together, these elements comprise

an organ that is easily the largest natural sound-producing

structure on the planet. The evident importance of acoustics to sperm whales is an a priori reason to suspect that

they are sensitive to manmade sound, including shipping

noise, especially because of their deep-diving habit. Deep

diving may constrain a sperm whale’s behavior, making any

forced change in response to disturbance costly. For example, the large fixed investment in time traveling to and

from feeding depth during a typical sperm whale foraging

dive means that any reduction in overall dive duration would

have a proportionally large effect on time spent foraging. In

addition, the one group of cetaceans (Ziphiidae, beaked

whales) for which there appears to be good evidence of

mortality resulting from exposure to anthropogenic sound

(as suggested by Frantzis 1998 and subsequent authors))

are also deep divers. While the mechanism leading to the

deaths of beaked whales remains uncertain, recent work by

Jepson et al. (2003) suggests that they suffer decompression sickness, perhaps as a result of surfacing too quickly

or remaining too long at the surface between dives in the

presence of noise. Bone damage recently observed in sperm

whales is morphologically similar to bone necrosis, a condition associated with saturation diving in humans. Moore

and Early (2004) suggested that the tissues of sperm whales

also become supersaturated with nitrogen, the effects of

which may be exacerbated by exposure to noise.

In summary, there are reasons for concern, but the evidence for serious impacts of anthropogenic sound (noise)

on sperm whales is equivocal. Few studies have been conducted, and published reports, many based on opportunistic observations, give contradictory results.

9.4.3 Oil and Gas Industry

Within the oil and gas industry, techniques have recently been developed to allow oil and gas to be exploited

seaward of the continental shelf. Rigs are currently operating at depths greater than 2000m and that limit continues to

be extended. This means that oil- and gas-related activities

are being pursued on a large scale in sperm whale habitat

for the first time. Seismic surveys, which use large arrays of

airguns to make intense sound pulses, have been the activity of most immediate concern. Large-scale seismic surveys

are employed during the exploration phase and there is an

increasing trend within the industry for smaller-scale seismic surveys to be repeated to monitor how oil reserves are

being exploited (so called four-dimensional surveys). During the exploitation phase of an oil field, there is increased

noise production and disturbance involved with drilling,

rig construction and operation, and the vessel traffic involved in servicing an oil field.

Workshop participants involved in field experiments in

the northern Gulf of Mexico (see Item 10.1, below) reported

preliminary results suggesting that sperm whales there, even

after many years of frequent exposure to seismic airgun

noise, exhibit at least subtle behavioral responses (e.g., Miller

noted some indication of declines in creak rates at distances

as much as 5-10km from the sound source). Despite the

difficulty of determining if and how these responses might

translate into biologically significant effects (e.g., changes

in vital rates), the very fact that sperm whales are such

deep-diving, acoustically oriented animals is cause for concern about the potential impacts of noise pollution on them.

10. FIELD PROGRAMS

10.1 Gulf of Mexico

During 2000-2002 the Southeast Fisheries Science Center (SEFSC) participated in a multifaceted, collaborative

sperm whale research program with funding from the Minerals Management Service (Mullin et al. 2003). These studies focused primarily on photo-identification, behavior, and

tagging of sperm whales in the northern Gulf of Mexico and

have been continued in the ongoing Sperm Whale Seismic

Study. Prior to those studies, SEFSC marine mammal assessment surveys were conducted as “piggy-backed” visual sighting surveys between 1996-2001. In addition, smallscale photo-identification studies in the northern Gulf of

Mexico have been conducted aboard small vessels during

the last two years.

In summer 2003 and spring 2004 the SEFSC conducted

dedicated marine mammal assessment surveys in oceanic

waters of the Gulf of Mexico between the continental shelf

break and the limit of the U.S. EEZ. These were combined

visual line-transect and passive acoustic surveys, employing the 90min count approach of Barlow and Taylor (2001).

In addition, nighttime small-scale acoustic surveys were
Page 18

conducted to provide fine-scale information on sperm whale

presence/absence throughout the Gulf and for comparison

to daytime encounter rates. Biopsy samples were collected

opportunistically by deploying a small inflatable boat. These

studies are expected to result in substantially higher abundance estimates for sperm whales in the Gulf than those

presently available due to the improved estimates of group

size and correction for visibility bias, or g(0). The SEFSC

plans to conduct its next large-scale vessel survey in the

Gulf of Mexico during summer 2007. That survey will likely

include two independent visual teams, passive acoustics,

dedicated biopsy sampling, and deployment of bottommounted recorders.

Gordon presented CARP/FP/7, an overview of the Sperm

Whale Seismic Study (SWSS). This study in the northern

Gulf of Mexico is sponsored and administered jointly by

the U.S. Minerals Management Service and the Texas A&M

Research Foundation, with additional partnerships (e.g.,

Office of Naval Research, National Science Foundation, and

National Marine Fisheries Service). The potential vulnerability of sperm whales to offshore petroleum exploration

and development operations, and especially to airgun noise,

has become a major concern as oil and gas activities have

expanded offshore into waters deeper than 200m. The fundamental goals of SWSS are to define “normal” behavior

and habitat use by sperm whales in the study area and

determine how these are altered as a result of seismic survey operations. SWSS includes the following technical

components: satellite imagery and limited physical oceanography input, a visual watch team, a passive acoustics

monitoring team, a satellite tag team (long-range tracking),

a D-tag team (controlled exposure studies), a DNA team, a

photo-identification and behavior team, and a “meso-scale”

team that conducts “classical” observational research from

a sailboat (see below). Thode called attention to a parallel

study sponsored by industry that involves passive acoustic monitoring to supplement onboard visual observation

as part of seismic survey mitigation protocols

(www.pamguard.org). The idea is to ensure that whales

within visual or acoustic range of a seismic vessel are detected and located in time to allow the operator to take

appropriate action (e.g., temporarily shutdown the airguns)

and reduce the likelihood of an impact.

In discussion, Gordon indicated that there was little

prospect in the immediate future of extending the satellite

tagging operation into waters outside the northern Gulf of

Mexico study area. Thus far, one tagged whale traveled to

the Gulf of Campeche (Mexico) and at least one male moved

into the North Atlantic and then returned. For the most part,

however, the population in the region appears to be fairly

stationary.

Gordon also presented CARP/PS&M/5, which described the initial results of work by the SWSS “meso-scale”

team, consisting mainly of photo-identification, acoustic

recording, biopsy sampling, and observations of behavior.

In the first year they worked from a large vessel with a team

of 15 (depending on a small rigid-hulled inflatable for close

approaches to the whales), and in the second year from a

smaller boat with a team of seven. Results demonstrated

that the sailboat with a small research team was much more

cost-effective than the large vessel and larger team of researchers.

In response to a question concerning the relative merits of large vs. small platforms for observing calves and

obtaining data to estimate calving rates, Whitehead stated

that, using the same platform and crew, he had observed a

very dramatic contrast in proportions of calves between

the eastern tropical Pacific on one hand and the Caribbean

Sea and Indian Ocean on the other.

10.2 Mediterranean Sea

A central question for the Mediterranean Sea, where

abundance and movements through the Strait of Gibraltar

are poorly known, is the extent to which sperm whales there

are isolated from those in the North Atlantic. Drouot et al.

(2004b) found frequency differences in mtDNA haplotypes

between sperm whales in the Mediterranean Sea and those

in the eastern North Atlantic.

Comprehensive assessment of sperm whale abundance

in the Mediterranean is precluded by the uneven distribution of effort and the complete lack of effort in the southeastern part (CARP/FP/11). More than 20 institutes and research groups are active in the Mediterranean, although

the sperm whale is a focal study subject for only a few of

them. Most of those primarily collect photo-identification and acoustic data in their local areas. Recent acoustic surveys conducted by the International Fund for Animal Welfare in the Ionian Sea (between southern Italy

and Greece) and in the southwestern Mediterranean

(along the North African coast from Morocco to Tunisia)

should provide abundance estimates for those areas in

the near future.

The sperm whale is one of the priority species for broadscale abundance surveys being planned under the Agreement on the Conservation of Cetaceans of the Black Sea,

Mediterranean Sea and Contiguous Atlantic Area

(ACCOBAMS). The earliest that any such survey is likely

to take place is 2007. It is anticipated that the surveys will

employ ships operating in double-platform mode (Buckland

Turnock method), which is considered the most effective

method for most of the species of interest. The primary data

for assessing sperm whale abundance, however, will be

acoustic (CARP/FP/11).

10.3 Eastern North Pacific

NOAA’s Southwest Fisheries Science Center in La Jolla,

California, has conducted multi-species cetacean linetransect surveys annually in the eastern North Pacific since

1986, and intermittently prior to that. Annual field effort is

typically 240 sea days on NOAA research ships. Study ar-
Page 19

eas vary from year to year, but have covered the eastern

tropical Pacific (1986-90, 1992, 1998-2000, and 2003), the U.S.

West Coast (1991, 1993, 1996, 2001), the U.S. EEZ of Hawaii

(2002), the Aleutian Islands, Gulf of Alaska and Bering Sea

(1996, 2004), and western Baja California and the Gulf of

California (1993). These are visual line-transect surveys

using 25X binoculars as the primary searching method, but

the surveys also include collecting a full suite of oceanographic measures of cetacean habitats. In addition to these

multi-species surveys, a dedicated sperm whale survey was

conducted in the eastern temperate Pacific in 1997 (Barlow

and Taylor 2005). Towed arrays were added to collect acoustic data on vocalizing dolphins and sperm whales in 1997

and in most subsequent years. Sperm whale density estimates from visual line-transect methods have been made

for the eastern tropical Pacific (Wade and Gerrodette 1993),

West Coast (Barlow 1995, Barlow 2003b), eastern temperate

Pacific (Barlow and Taylor 2005), and Hawaii (Barlow 2003c)

study areas. An acoustic line-transect estimate of sperm

whale density was also made for the eastern temperate Pacific (Barlow and Taylor 2005). Multi-species line-transect

surveys by the SWFSC are expected to continue into the

foreseeable future, with 120-240 sea days per year on NOAA

research vessels. In summer/fall of 2005, survey areas will

include two distinct regions: (1) U.S. EEZ waters around

Johnston and Palmyra Atolls and surrounding international

waters between those islands and Hawaii, and (2) the U.S.

West Coast. In summer/fall of 2006, survey efforts will return to the eastern tropical Pacific.

Clapham reported that the National Marine Mammal

Laboratory in Seattle holds some fluke photographs and

biopsies from the vicinity of the Aleutian Islands, but there

are no concrete plans for research on sperm whales in that

laboratory. The autonomous listening devices deployed by

Sue Moore and colleagues may have generated some useful data on sperm whales. Although the U.S. Navy’s bottom-mounted hydrophone arrays (Sound Surveillance System, or SOSUS) remain active in the North Pacific, Barlow

pointed out that the archived components generally do not

go above about 100Hz, which means they have little to offer

regarding sperm whales.

The ongoing sperm whale depredation study in the Gulf

of Alaska will continue to collect data on sperm whale behavior, acoustics, genetics, and photo-identification (see

CARP/A&D/2, Thode, Scripps Institution of Oceanography; and CARP/HI/10, Straley, University of Alaska Southeast).

Jaquet summarized CARP/FP/8, describing sperm whale

studies in the Gulf of California, Mexico, since 1998. The six

field seasons to date have spanned an average of one month

each, 564 individual sperm whales have been identified,

and further research is planned. Traditional methods (developed by Whitehead and colleagues in the 1980s) have

been used to assess distribution, abundance, residency,

social organization, habitat use, patterns of small-scale

movement, large-scale movements, genetics, and coda repertoires of the whales in the Gulf. The use of similar methods in different study areas allows comparisons between

regions and consideration of spatial variation in social organization, mating behavior, habitat use, etc. Preliminary

analyses suggest that social organization, group size, and

mating strategy are similar in the Gulf of California, the

Galápagos, and Chile, but differ substantially between these

areas and the northern Gulf of Mexico, where similar techniques were used in summer 2004 (see CARP/PS&M/5).

Differences have been observed in habitat use and site fidelity between sperm whales in the Gulf of California and

those off the Galápagos and Chile, with the whales using

mainly relatively shallow habitat (600-1000m) in the Gulf of

California and showing high site fidelity for a small area of

the central Gulf. Eleven individuals first identified in the

Galápagos were resighted in the Gulf of California, a straightline distance of about 3800km.

10.4 Western North Pacific

Kato noted the large-scale Japanese sighting survey

program in the western North Pacific since the mid-1970s

and introduced CARP/FP/5 and CARP/FP/10. These papers examined monthly changes in spatial distribution

and yearly changes in encounter rates of sperm whales.

Preliminary estimates of abundance were also produced.

The large-scale program is expected to continue. Kato

also drew attention to specific research projects in Japan

on sperm whale acoustics and to data-logger experiments

with sperm whales. CARP/FP/6 provided an overview of

Japan’s whale research program in the western and central North Pacific (JARPN, 1994-1999, and JARPN-II, 2000

and ongoing), and CARP/A&D/6 analyzed sperm whale

distribution in the western North Pacific from sightings

surveys between 1994 and 2004.

10.5 Western North Atlantic and Caribbean

The Southeast Fisheries Science Center conducts largescale vessel surveys in Atlantic waters of the U.S. EEZ

between Florida and Maryland on a two- to three-year cycle.

The last large-scale assessment survey was conducted in

summer 2004. It involved two independent visual sighting

teams and passive acoustic monitoring. High densities of

sperm whales were encountered along the continental shelf

break north of Cape Hatteras, and a survey is planned for

summer 2005 to collect biopsies from sperm whales and

other species in that area. Further, a “process-oriented”

ecosystem survey is being planned for summer 2006, to

include intensive hydrographic sampling, active fishery

acoustics to assess biomass of food species, mid-water

trawling, intensive biopsy sampling, and visual marine mammal sightings (Garrison, pers. comm.). The goal will be to

evaluate habitat features that account for the observed high

densities of sperm whales and other marine mammals in this

region.
Page 20

The Northeast Fisheries Science Center will continue

to conduct summer multispecies line-transect (ship and aircraft) surveys in shelf and offshore waters between Maryland (38oN) and the Gulf of St. Lawrence. Surveys are conducted at 3- to 5-year intervals. An aircraft is used to survey

shelf (0-200m) waters in the entire survey region. Shelf edge

(200m) and oceanic waters between Maryland and the U.S./

Canada EEZ border are surveyed by ship. Ship surveys

include visual (two independent teams) and acoustic components. Further, in summer 2006 or 2007 a dedicated biopsy sampling survey will be conducted throughout the

survey region (Waring, pers. comm.).

Whitehead reported that the Canadian Department of

Fisheries and Oceans conducts marine mammal surveys

sporadically, mainly off Newfoundland. His own shipboard

work recently involved a visit to the Sargasso Sea, mainly

to test equipment. Very high densities of sperm whales were

found there. Whitehead noted that the western North Atlantic may be of particular interest because it is one of very

few areas of the world where sperm whales were not subjected to modern industrial whaling.

Whitehead also reported that he and his group at

Dalhousie University have an ongoing field program at

Dominica in the West Indies. Kato called attention to a

Caribbean FAO “ecosystem” study that began in 2002. Several participating countries have an interest in the sperm

whale and are compiling sightings.

10.6 Eastern and Central North Atlantic

 (including Iceland)

A long-term study in the Azores, principally involving

acoustic monitoring and photo-identification, was funded

by the International Fund for Animal Welfare from 1987-

1995 (Leaper et al. 1992; Matthews et al. 2001). This study

has been continued to some extent by the University of the

Azores and by some of the whalewatching operators (Gordon, pers. comm.).

From 4 June to 2 July 2004 the Norwegian R/V G.O. Sars

conducted a multidisciplinary survey along the northern

portion of the Mid-Atlantic Ridge (Reykjanes Ridge to the

Azores). Sperm whales were the most frequently sighted

cetaceans. Data analyses will be available in summer 2005

(Waring, pers. comm.).

A photo-identification study ran for many years (1987-

1990s) along the west coast of Norway, based on a

whalewatching operation (Lettevall et al. 1993; Hastie et al..

2003). Madsen reported that he and Mark Johnson have a

continuing collaboration with B. Møhl to study sperm whale

acoustics off Norway.

A regular series of quantitative acoustic surveys of the

Shetland Faeroes channel and waters to the northwest of

Scotland have been conducted since 2000 by researchers

from Aberdeen University and the Sea Mammal Research

Unit (SMRU) using the Fisheries Research Vessel Scotia.

Two to three surveys are carried out each year and this

series is currently being continued (Hastie et al. 2003).

Norwegian NASS surveys and serial yearly partial-coverage surveys, primarily aimed at minke whales, have been

combined to produce two estimates of abundance for sperm

whales in the northeastern Atlantic. These estimates are

not corrected for availability bias (Øien 2005). An estimate

for the NASS-2001 survey area – East Greenland to the

Faroe Shelf and Jan Mayen – is corrected for availability

bias (Gunnlaugsson et al. 2002). A comparison of sperm

whale sighting rates from the series of NASS surveys 1987-

2001 and observations from O-group surveys around Iceland, 1982-1995, shows a decline in both cases. This is contrary to increases in sighting rates of other species

(Gunnlaugsson 2004).

The Norwegian minke whale surveys are expected to

continue. The next large-scale NASS survey is scheduled

for 2007 and will be coordinated by NAMMCO in collaboration with the IWC.

10.7 South Pacific

Dawson provided a summary of the Otago University

project at Kaikoura, NZ (CARP/FP/1). The sperm whales

there are comprised of (a) “residents” that remain in the

study area for several weeks or months, and return to it

regularly, and (b) “transients” that appear to be passing

through. Several residents have been seen six years in a

row, and two that were first identified in 1991 were still visiting Kaikoura in 2002. Mark-recapture analysis of photoidentification data collected from 1990-2001 suggested that

an average of 79 (CV = 23%) whales were present in any one

summer or winter season (Childerhouse et al. 1995; Gormley

2002). There is no evidence of a trend, and no evidence of

seasonal differences in abundance. The photo-identification catalog contains 202 individuals. To date, all well-photographed individuals have been uniquely identifiable. Mark

change has been observed, but over a period of 4.5 years

has been insufficient to cause misidentification

(Childerhouse et al. 1996). Both whaling records (Grady 1982)

and stereophotogrammetry (Dawson et al. 1995) indicate

that, except for rare visits by mixed groups, the sperm whales

routinely present off Kaikoura are males. Age-length data

(Ohsumi 1977) suggest that about two thirds are between

10-20 years old, and thus pubertal (Chessum 1992; Dawson

et al. 1995). The remaining third are aged 25 years or older.

Abundance is similar between summer and winter, but

distribution differs significantly; whales are found closer

inshore in winter. Fish (especially grouper) become more

important in the winter diet (Gaskin and Cawthorn 1967). It

seems likely that this dietary change causes of the shift in

distribution. Dives and surface intervals were significantly

longer in summer (mean dive time 43.9 vs. 38.7 min; mean

surface interval 9.3 vs. 8.8 min). Whales covered, on average, 0.86nmi (CV = 50%) between consecutive flukes-up
Page 21

(Jaquet et al. 2000). Large whales did not dive for longer

than small whales, and dive time and surface recovery period were only very weakly correlated. Unlike sperm whales

in nursery groups, males at Kaikoura very seldom spent

extended periods (>15min) at the surface. These males spent

about 83% of their total time underwater.

Off Kaikoura, sperm whales are the focus of

whalewatching, which involves the use of boats and aircraft to view the animals year-round. Richter et al. (2003)

made boat-based and shore-based observations to quantify the responses of whales to the whalewatching activities. Shore-based observations showed that blow interval

decreased significantly in the presence of the research vessel and/or whalewatching platforms. Data collected from

the research vessel showed that both whalewatching boats

and planes, individually or together, caused significant increases in time spent at the surface and in the frequency

and number of heading changes. In the case of boats, there

was also a significant decrease in the time to first click.

Aerial behavior was significantly more frequent when only

the research vessel was present, which is likely due to its

closer positioning to surfacing whales after acoustic tracking. Transients react more frequently and more strongly to

vessels than do residents. For this reason, and because of

their more inshore distribution, residents receive the majority of whalewatching attention. Reactions to whalewatching

vessels vary significantly among different individuals, some

of which are very tolerant. Reactions also vary with season,

for reasons that are not understood. On balance, effects on

resident whales, while statistically detectable, appear not

to be of any serious biological consequence. However, current whalewatching effort on residents is high, such that

individuals are likely to spend approximately half of their

surfacing time during the busy summer season in the company of one or more vessels.

Dawson described an acoustic and photo-identification survey of sperm whales conducted in Tongan waters

from May to September 2003, focusing on the area around

Vava’u and between Vava’u and the Ha’apai island groups.

This was a collaboration between scientists at Otago University in Dunedin, New Zealand, and the Southwest Fisheries Sciences Center in La Jolla, California. In addition to

the survey in Tonga, a hydrophone array was towed on the

voyage from New Zealand’s east cape to Tonga. Despite

poor weather that restricted array deployment, sperm whales

were heard on six days of this 9-day passage. In Tongan

waters, mixed groups including calves were found most often along the 1000m contour between the Vava’u and

Ha’apai island groups. Groups of males were occasionally

seen to the east and west of Vava’u. In one case, these

whales were silent for extended periods. Detection distances

under sail at slow speeds (<6 knots) were around 10nmi for

usual clicks. Under good conditions, slow clicks could be

heard considerably farther away (ca. 20nmi).

Whitehead expressed interest in resuming work in the

South Pacific, having carried out extensive studies there

(Chile to the Gulf of California) from 1985-2000. Future efforts by his group would focus on, among other things,

estimating survival rates.

10.8 Odyssey

Ocean Alliance’s “Voyage of the Odyssey” program is a

five-year (2000-2005) global effort designed to gather

baseline data on levels and potential effects of synthetic

contaminants in the world’s oceans. Detailed information

on methods and synopses of the data collected thus far

were presented in CARP/FP/4 and CARP/FP/9. The ship is

expected to return to the U.S. east coast in autumn 2005. A

new voyage is expected to begin in 2007 (Godard, pers.

comm.).

Persistent lipophilic contaminants accumulate and

biomagnify in marine mammals because of their high body

fat content, their relatively long life span, and their high

trophic position within marine food webs. Of all marine mammals, the sperm whale was chosen as the study species for

the program because of its global distribution and because

it can be identified and tracked acoustically. The Odyssey’s

route was designed to include regions historically known

as sperm whale grounds as well as regions little or poorly

surveyed.

Close to 1000 biopsies had been collected to the time of

the workshop; a final sample size of about 1200 is expected

by the program’s end. Whenever possible, each biopsy

collected by the Odyssey team is divided into subsamples

that can provide material for the following analyses: contaminant burden, biomarkers of exposure to and effects of

contaminants, genetics, stable isotopes, and fatty acids.

Godard recommended that biopsy efforts from other platforms follow similar subsampling protocols in order to maximize the information obtained from each individual sperm

whale sampled. According to Godard, analyses of contaminant burdens can be expected to provide information on

the overall level of environmental contaminants in sperm

whale tissues. In addition, differences in contaminant patterns may be useful as markers for population or stock differentiation. Studies of the potential effects of environmental contaminants on the health of sperm whales (cf. Godard

et al. 2004) are ongoing.

Godard acknowledged that contaminant analyses can

be costly and that many samples have yet to be analyzed.

Arrangements have been made to have some of the material

analyzed in Christina Fossi’s laboratory at the Universitá di

Siena, Italy. Godard acknowledged that zonation of contaminant concentrations in skin and blubber can be a confounding factor in some analyses. She noted that sex would

be determined for each biopsy and that a gross estimate of

the individual’s body size (as a proxy for age) was also

available in each case.

In addition to the toxicology component, the Ocean

Alliance program includes genetics and acoustics compo-
Page 22

nents. The initial genetic analyses will provide information

on sex distribution, sex ratio, and the relationship between

sex and contaminant burden. Acoustic recordings associated with the program also may provide information that is

useful for sperm whale population assessment. After a brief

discussion of this latter point, the workshop concluded

that it was unlikely the acoustics data could be used retrospectively to generate meaningful density estimates. It was

agreed that, at a minimum, the acoustics data should be

archived at Cornell University.

10.9 Indian Ocean

Bannister briefly described a proposal to develop methods to determine sperm whale distribution, population size

and trend, habitat, and conservation status in Australian

waters, particularly off southwestern Australia where the

commercial sperm whale fishery operated from 1956 to 1978

(CARP/FP/2). A pilot study has been funded for 2005, with

two main elements: (a) to review an earlier proposal for aerial

surveys off Albany, Western Australia, and (b) to review

methods of DNA extraction and to sequence mtDNA from

sperm whale teeth. The first element would provide a proposal for surveys of relative abundance to be compared

against data from the earlier whaling aerial spotter operation. The second element would consist of an analysis of

mtDNA diversity based on teeth collected from the commercial catch.

10.10 Antarctic

Kato summarized the current status of the IWC’s IDCR/

SOWER project, which began in 1978/79 with the primary

objective of stock assessment of Antarctic minke whales.

The project has now completed its third set of circumpolar

surveys. Future planning is ongoing through a special working group. Further detailed planning will take place at the

upcoming (2005) meeting of the Scientific Committee. The

sperm whale is a potential priority, but it is important to

consider that the program’s Antarctic focus means that only

large males can be investigated. Kato emphasized that these

cruises were sampling only the large-male component of

the Southern Ocean population and therefore could not be

expected to provide estimates of the whole population. Best

added that, in fact, they sample only that part of the largemale component that is south of 60oS, and that sampling the

whole adult male component would require redesign of the

surveys and extending the northern boundary of the study

area northward.

CARP/FP/6 provided an overview of Japan’s Antarctic

whale research program (JARPA), and CARP/A&D/7 presented new information on sperm whale abundance and

distribution in Antarctic Areas IIIE, IV, V, and VIW (35oE to

145oW). Ohsumi stated that there is interest in estimating

the biomass of sperm whales as input to ecosystem models.

11. FUTURE WORK

Participants recognized that the overarching theme of

the workshop was population assessment. Development of

such an assessment will require the following (not necessarily in order of priority):

11.1 Need to Understand the True, Underlying

 Structure of Populations

The need for an improved understanding of population

structure in sperm whales was a frequent theme of the workshop, and indeed a significant part of the rationale for convening it. “Structure” can be interpreted variously as applying to, or being driven by, differences in sex, age, behavior, geography, genetics, or culture. In the context of this

workshop, population structure was essentially considered

the same as stock structure, with “stock” interpreted to

mean that the internal dynamics of a group of animals are

more important than external exchange with other groups.

Given that the overarching theme of the workshop was

population assessment, it is important to consider whether

such assessment is likely to be sensitive to a range of scales

of population structure. For example, a reasonable initial

step might be to establish a series of possible scales ranging, say, from ocean basins to 5-degree squares. If depletion levels appear similar across that range and at the extremes, there may be little need to worry about getting things

exactly right. Additional work on population structure may

not then be a high priority, at least from the perspective of

assessment.

Although genetics is often invoked as a key factor in

determining population structure, it was considered more

appropriate here to consider genetics a consequence of,

not a driving factor for, the structure. In other words, genetics provides a way of assessing structure but does not

necessarily cause it, and therefore genetic difference constitutes a marker for other structuring forces. A global review of sperm whale genetics is clearly a priority. This will

require, as a first step, an inventory of what material is available for genetic analyses, including where and how it was

collected, by whom, etc. Such a process has already begun

and should be encouraged and supported (see CARP/

PS&M/1). The next steps would be to analyze the available

material, and then to conduct directed sampling based on

the initial results and working hypotheses.

Participants struggled with the problem of how to define hypothetical population units (i.e., strata), recognizing

that the traditional concept of geographic boundaries may

not adequately reflect cultural aspects of sperm whale popu-
Page 23

lation structure (cf. Whitehead et al. 2004). A non-traditional view requires the integration of genetics with finerscale “cultural” markers such as coda dialects (CARP/

PS&M/ 2), as well as basic data on modal and extreme movements of individuals (e.g., from satellite tagging and photoidentification), morphology (e.g., scarring), and knowledge

about mating systems and foraging ecology (e.g., from historical whaling data). CARP/PS&M/1 and CARP/PS&M/3,

together, provided an initial basis for such an integrative

approach.

Using a hierarchical model, one might begin by asking:

Are there multiple distinct units within the global sperm

whale population or not? In addressing that question, one

can choose between a deductive process of assembling the

available data and looking for patterns, and a more inductive process using a predictive ecological framework.

Another way of approaching the issue of population

structure might be with the following series of questions:

1. Is there a single global population, or is meaningful structure present within that population?

2. If there are distinct groups of sperm whales, are they or

are they not geographically overlapping?

3. What markers, in addition to or instead of genetic markers, can be used to define sperm whale populations (e.g.,

differences in behavior or “culture”)?

The following alternatives for establishing strata to

compare and test were agreed:

1. Use as an initial working hypothesis that the sperm

whales in each ocean basin represent separate units

(stocks).

2. Use strata alternatively based on: oceanography, geography, ecology (prey distribution), or social or cultural

variables (coda repertoires), as well as a “no structure”

hypothesis.

Among the tools that might be used for the above analyses are: tagging (movement data), photo-identification,

acoustics, and biopsies (DNA, contaminants, stable isotopes).

As a way of trying to rank various methods of addressing population structure, a straw poll of workshop participants, on a scale of 1 to 3 (low to high), had the following

results:

• High – parasite and predator (scarring inflicted by killer

whales) analyses, Discovery mark returns, photoidentification, mtDNA sequencing, nuclear DNA markers (microsatellites and single nucleotide polymorphisms), satellite tagging, vocal (coda) analyses, trace

analysis of tooth sections, Y-chromosome sequence

variation, and breeding-area studies (seasons out of

phase).

• Medium – patterns of change in catch or sightings per

unit of effort, contaminant analyses.

• Low – morphometrics, morphology, distribution of catch

or sightings data, allozymes.

11.2 Need to Obtain Accurate Estimates of the

 Numbers of Whales (Preferably by Sex and

 Size Class) Removed by Whaling from Each

 Population

Although ideally catch and associated data (including

some kind of effort index) should be collected at a fine scale,

limitations of time and cost are unavoidable in practical

terms. Particularly in regard to historical (pre-20th century)

whaling where there is substantial uncertainty, information

on the statistical properties (e.g., ideally confidence limits,

but at least some indication of lower and upper bounds) of

catch estimates should be provided. Also when possible, it

is preferable to explore a range of mortality factors to “correct” catch data for hunting loss (struck/lost) in different

areas and times. While corrections to account for hunting

loss and allocation of catches to sex should be straightforward for much of the era of modern whaling (with exceptions as noted under Item 9.1), this is not the case for the

open-boat era.

At what point is further pursuit of improved catch data

no longer cost-effective? The workshop was unable to answer this question conclusively. However, participants

agreed that the answer depends in large part on the scale of

analysis and the size of the area inhabited by the “population” of interest. It was further noted that there was likely a

strong temporal effect, such that efforts to collect better

information from the early days of sperm whaling (especially the 18th century) are likely to be more worthwhile

than efforts to improve the more recent catch history.

The workshop emphasized the importance of reaching

closure on the revised modern catch data for the North

Pacific, and the need to specify sex to the maximum extent

possible in the case of sperm whales. It was agreed, for

example, that the sex composition of the validated sample

of catches in the North Pacific could be extrapolated in the

manner outlined by Kasuya (2003).

11.3 Need to Estimate Abundance for a High

 Proportion of Waters Worldwide

Whitehead (2002) extrapolated densities from a heterogeneous set of abundance surveys to estimate current sperm

whale numbers worldwide. Additional areas of the world’s

oceans need to be surveyed to validate those density estimates. Special emphasis should be given to waters of the

Atlantic and Indian Oceans because only small proportions

of them have been surveyed systematically for sperm whales.
Page 24

11.3.1 Line-Transect Surveys: Visual and

 Acoustic

Combined visual and acoustic (hybrid) surveys need

to be continued for the immediate future, but it is reasonable to expect acoustic-only surveys to become the norm

eventually, given their relative efficiency. As explained more

fully under Item 10.1 (and see CARP/PS&M/5), the current

state of acoustic survey methodology allows for the use of

small boats and platforms of opportunity, which obviates

the need for large field teams and costly ship charters.

There was some disagreement on the question of how

much further development is necessary for acoustic surveys, but it was agreed that unprocessed (“raw”) acoustic

data should be carefully organized and archived so that as

methods of analysis improve, those data can be reanalyzed.

A particular need for acoustic methods is to determine how

to estimate group size when surveying areas where sperm

whales occur in large groups.

Further refinement of g(0) is needed for visual surveys.

This will require more dive data (e.g., from data loggers),

more parallel visual and acoustic surveys for calibration,

and more modeling. A caveat for telemetry data is that they

are useful for estimating g(0) for individuals but not necessarily for groups. It was also noted that the proportions of

time spent by whales resting vs. socializing are critical to

g(0), yet these patterns vary a great deal between ocean

areas. Whitehead indicated that groups of sperm whales

tend to be larger and more compact in the Pacific than in the

Atlantic. As better estimates of g(0) become available, they

can be used to reanalyze data from past surveys as well as

to analyze data from future surveys, recognizing the potential variability among surveys.

Kato stated that Japan has been carrying out shipboard

sighting surveys to obtain abundance estimates for most

species because this methodology is reliable and realistic.

However, because of the necessity to have appropriate g(0)

values, acoustic surveys are also useful for sperm whales

or long-diving cetaceans. As a consequence, the National

Research Institute of Far Seas Fisheries has started simultaneous visual and acoustic surveys for sperm whales. Furthermore, the Institute has succeeded in obtaining diveprofile data by attaching data loggers to sperm whales and

Baird’s beaked whales. These data can be used to improve

estimates of g(0) for sperm whales.

The workshop discussed whether the effort and observations (visual and/or acoustic) from the Odyssey voyage

could be used retrospectively to generate useful density

estimates ex post facto. Also, Kerr noted that the ship would

be visiting the Twelve-Forty (12oN by 40oW) Ground in the

North Atlantic in summer 2005, and wondered whether plans

could incorporate the necessary protocols for obtaining

useful data for density estimation. More generally, platforms of opportunity (e.g., seismic survey vessels, transoceanic shipping, and oceanographic research) offer the

possibility of obtaining useful data at little cost but also the

risk of biases of various sorts. Some platforms carry sophisticated oceanographic equipment or operate year-round

in all conditions. The best platforms are those that follow a

systematic or grid design and that travel at low or moderate

speed. Acoustic survey techniques are particularly amenable to use on platforms of opportunity.

11.3.2 Mark-Recapture Studies

Photographic mark-recapture methods of estimating

abundance are useful and have been applied successfully

over relatively small spatial scales. They are likely to be

most useful for population assessment in fairly closed areas such as the Mediterranean Sea, Gulf of Mexico, and

Gulf of California. However, the large spatial scales over

which most sperm whale populations occur mean that photoidentification is unlikely to be a generally useful technique

for population estimation. For further elaboration of the

relative merits of this and other techniques, see Items 5.2

and 5.5.

11.3.3 Methods of Extrapolation

Several suggestions were offered on ways to validate

or improve the extrapolation procedures used by Whitehead (2002) to estimate global sperm whale abundance. With

access to unprocessed (and not just summarized) data from

surveys, it should be possible to extrapolate to additional

areas using multivariate approaches. Kato reported that the

Worldwide Map of Cetacean Distribution based on Japanese sightings data (Miyashita et al. 1995) is being updated. When available (possibly 2006), it may be of use in

decisions about extrapolation. Finally, collation of data from

various platforms of opportunity (see 11.7.2, below) might

also provide insights about presence, absence, and relative

densities of sperm whales in unsurveyed areas.

11.4 Need to Improve Understanding of the

 Demographics of Population Growth

Among the important parameters to estimate are individual growth rate, average age at sexual maturity, pregnancy rate, and survival rate (by age and sex).

Whitehead’s (2002) model is very sensitive to rmax.

Therefore, validation or improvement of the values used for

that parameter must be a high priority. Knowing the survival rate of adult female sperm whales in their prime would

substantially improve population modeling. Because of the

great difficulty of obtaining an unbiased sample from the

data presently available, obtaining estimates from a “closed”

population (e.g., Caribbean Sea or Gulf of Mexico) using

fishery-independent data (e.g., photo-identification) is an

option to consider (cf. Barlow and Clapham 1997). It is uncertain, however, whether any isolated or relatively isolated

population would be representative of the species overall.
Page 25

Best pointed out that survival rates calculated in this manner (i.e., using photo-identification for a specific ocean area)

would require a substantial time series to acquire sufficient

precision, and that the longer the time span, the more likely

that the estimates would be confounded by emigration and

by the likely age-specific nature of sperm whale survival.

Because of the time-consuming nature of such studies, it is

important to capitalize on data already available and on

programs that are in place and continuing. For example,

approximately 20 years of data are available for the eastern

Pacific and the Caribbean (Whitehead, pers. comm.).

Although there might be some merit in re-analyzing the

whaling-derived data (Best et al. 1984), this was not considered particularly promising, as the same problems of heterogeneity would remain. Another suggestion was that rmax

be estimated independently for females, and that modeling

be limited to the female component of the population. A

drawback, of course, is that male survival is likely critical to

maintaining high pregnancy rates. Regarding the relevance

of male survival to rate of increase, Whitehead suggested

that integration of photo-identification and genetics data

could provide a means of establishing paternity, and therefore assessing “social” maturity in males. Incorporation of

acoustic or photogrammetric measurements would also help

to generate estimates of body size at “social” maturity.

Besides better estimates of survival rate, estimates of

gross reproductive rate are needed. These are currently

determined from the ratios of calves to other animals in the

school, but problems with field determination of “calves”

(and the identification of the component of the population

represented by the other animals in the school) indicate

that more rigorous methods are needed to assess reproductive rate.

Potential methods to investigate reproductive status

of individuals include: (1) fecal steroid hormone analysis to

assess pregnancy and sexual maturity, (2) hormone assays

of biopsies, (3) hormone assays of blow expirate, (4) longitudinal photo-identification studies of calves to determine

age at sexual or social maturity (assuming that calves are

well enough marked for photo-identification), and (5) longterm photogrammetric studies to track individual growth.

More use might also be made of tooth sections in large

samples from the whaling industry (assuming that such teeth

are linked to biological data on the specimens from which

they were extracted), and data from satellite tracking could

be informative for some aspects of life history.

Ohsumi and Gunnlaugsson suggested that research

catches of sperm whales, under present-day environmental

conditions, would be a valuable supplement to other kinds

of life history data. Workshop participants noted, however,

that the value of such data would depend on the extent to

which the samples duplicate existing samples and on the

number of individuals sampled. Unless many individuals

were sampled, which would necessitate large-scale whaling, the value of data from research catches will be low.

Strandings, especially mass strandings, might be investigated as a source of relevant data, but the same qualification as mentioned for research catches applies – i.e., inevitably small sample size and thus inadequate statistical

power.

11.5 Need to Develop Sperm Whale Population

 Models

There was general agreement that modeling of sperm

whale populations should move as quickly as possible into

a Bayesian, and preferably an age-structured, framework.

Population models for sperm whales need to be compatible with (i.e., more closely matched to) the quality of

available data. As is always true of models, it is important

that the uncertainty associated with data and rates used as

input be explicitly represented.

Best considered that development of a more appropriate model of the effects of relative male depletion is essential for proper assessment of the current status of sperm

whales. During the major 20th century episode of exploitation, many more males than females were taken, and inevitably a population model incorporating catches by sex would

show that males (and particularly large males) have been

depleted substantially more than females. This is true even

after allowing for the substantial under-reporting of females

in the Soviet (pelagic; Brownell et al. 2000) and Japanese

(shore station; Kasuya 1999) catches. The implications for

the population trajectory would depend critically on whether

such depletion was sufficient to adversely affect female

reproductive success. One assumption of the previous male

depletion model used by the IWC Scientific Committee has

been shown by recent field studies to be inappropriate (although probably risk-averse), and there is an ongoing need

to establish: (a) the threshold size of breeding males and (b)

the effective sex ratio of breeding males to mature females.

Addressing these questions adequately will require carefully planned field experiments, as well as further simulation

modeling. Lengthy tracking of individual roving males, if

feasible, could prove informative.

Gunnlaugsson noted that although some stable CPUE

series from modern whaling operations may not be of any

significance, observations of historic depletion and trend

should be reflected in the output of population models if

such models are to be considered realistic. Alternatively,

priors on depletion levels and trends can be used as input

to the models to estimate population growth rate. With an

age-structured model, the observed mortality rates from “age

readings” (GLGs in teeth) could be compared to the mortalities predicted by the model, or even fitted in the model.

Gunnlaugsson urged that estimates of effort should be collected wherever feasible. In his view, a decline in CPUE in a

fishery that is unrestricted in range is generally believed to

reflect a decline in the stock, and possibly a disproportionately severe decline (i.e., non-linearity).

The issue of how, and to what degree, CPUE data should

be incorporated into any sperm whale model was controversial. On one side, there was a view that all CPUE data are
Page 26

suspect and that inherent biases confound virtually any

analysis that uses such data. On the other side, it was noted

that in some cases of “pure” sperm whale fisheries (i.e.,

with no other whale species as alternate targets), the relatively “clean” CPUE data would be informative for a sufficiently resolved model. Examples might be the 19th century

sperm whale fisheries on the Japan Ground (Bannister et al.

1981) and around the Galápagos (Hope and Whitehead 1991)

and the 20th century fisheries off South Africa (Best 1974

and pers. comm.) and Western Australia (Kirkwood and

Bannister 1980).

Additional suggestions to improve Whitehead’s model

included: (1) further exploration of the density dependent

response using additional simulations and perhaps incorporating lessons from work with other species (e.g., seals in

the UK) and (2) incorporating a variable, time-dependent

carrying capacity (K) to reflect possible changes in global

primary productivity over time.

11.6 Biological Significance of Present-Day

 “Changes”

11.6.1 Climate Change

Whitehead reported that the two main sperm whale

“clans” around the Galápagos were strongly affected by El

Niño. If the incidence of such events increases, as expected

as a result of climate change, this could significantly influence the balance among sperm whale clans according to

their different adaptive characteristics. Some of the implications of climate change for sperm whale populations were

addressed by Whitehead et al. (2004), who concluded that

“cultural diversity” in sperm whales may need to be preserved as a way of minimizing the risks to the species from

climate change.

Participants discussed briefly whether sperm whales,

as oceanic animals that forage at great depths, might be

less vulnerable to the effects of climate change than animals that depend more directly on surface plankton. The

balance of opinion was that in most models, primary production near the surface is closely linked to deep-ocean

conditions, and therefore it is reasonable to assume that

effects on the former can be extrapolated to the latter.

11.6.2 Chemical Pollutants

In some other taxa (studied in the laboratory or the wild),

high levels of some of the pollutants detected in sperm

whales have been implicated in reproductive or immunological problems. Too little is known to assess whether pollutants cause or contribute to such disorders in sperm

whales; however, if problems do exist, or could arise in the

future, they would potentially compromise already-low rates

of population growth and recovery in this species.

The workshop agreed on the value of continuing to

collect, analyze, and archive sperm whale tissues for contaminant analyses. Understanding the effects of the various chemicals, and dose:response relationships, requires

long-term effort, but reporting of tissue levels in the meantime should continue. In addition, collection and analyses

of contaminant levels in known prey of sperm whales would

be informative. According to Godard, the standards and

protocols for tissue collections and archives, as outlined in

CARP/FP/9, are in conformity with those of the National

Institute of Standards and Technology, which serves as the

long-term storage site for archived tissues. Ocean Alliance

was encouraged to explore collaboration with the IWC’s

Pollution 2000+ project.

Godard and Mesnick provided a table to guide biopsy

collection and storage (Table 1).

11.6.3 Changing Prey Base

This topic was recognized as an important one, and the

workshop agreed that methods for monitoring feeding success (e.g., creak rates, defecation rates, blubber thickness

measurements; see Item 8.1) should be integrated as fully

as possible into field studies of sperm whales.

11.6.4 Increased Underwater Sound

There has been growing concern about the impacts of

manmade sound on cetaceans, including sperm whales (see

Item 9.4). These concerns range from the discrete effects of

activities with limited duration over limited time periods to

the more generalized (chronic, cumulative) effects of such

things as ship traffic.

The most sensitive technique for evaluating short-term

effects on behavior involves monitoring the behavior of a

whale before, during, and after a controlled exposure to

sound (Tyack et al. 2003). Such experiments can be used to

define a dose:response relationship between a sound exposure and a behavioral response. If the experiment is designed to measure an important type of behavior whose

function is understood, then it can address the question of

how much sound prevents an animal from meeting a need

such as foraging, maintaining contact between mother and

calf, or finding a mate. The area of greatest uncertainty is

predicting how such disruption affects growth, survival, or

reproduction of the individual (National Research Council

2005). Larger spatial scales and longer time series are clearly

needed to address this uncertainty.

It was noted that the subject of underwater sound and

its effects on marine mammals has been or is being addressed

in a comprehensive manner by a number of U.S. agencies,

notably the Ocean Commission, the Marine Mammal Commission, and the National Research Council (2005).
Page 27

11.6.5 Other Factors

The ongoing human-caused mortality from entanglements and ship strikes was noted. Reportedly high rates of

driftnet mortality in the Mediterranean Sea have been a

conservation issue for a considerable time and were discussed at the annual IWC Scientific Committee meeting in

2004 (IWC 2005). At the present workshop, it was agreed

that the IWC should be encouraged to continue compiling

data on incidental catches of cetaceans, and that special

attention be given to sperm whales in the Mediterranean

and in other areas where driftnetting overlaps the occurrence of sperm whales. Also, it was suggested that analyses of scarring on the bodies of living sperm whales (particularly in the region of the tail peduncle) could help elucidate the incidence of entanglement.

Sperm whale interactions with longline fisheries have

become a major management issue in some regions (Gulf of

Alaska, Southern Ocean), and they also represent a significant scientific challenge in determining their ecological significance and in finding ways of solving or mitigating the

problem. The workshop recommended that data be collected

in longline fisheries to determine the nature and extent of

interactions with sperm whales and to improve knowledge

of the whales’ foraging patterns. Standard data collection

protocols are essential for trend analyses.

11.6.6 Implications for Changes in Vital Rates

No attempt was made to investigate this issue in detail.

The workshop simply noted the difficulty of inferring

changes in vital rates from potential effects of such things

as exposure to chemical contaminants or noise, reduced

availability of prey, or climate change.

11.7 Implementing Components of Needed

 Research

11.7.1 Agencies with Interest

Some of the agencies with an ongoing interest in sperm

whale assessment were mentioned under agenda Item 2 –

the U.S. National Marine Fisheries Service (need to evaluate classification as Endangered, need to complete a ReTable 1. Analyses facilitated by biopsies, with handling and storage procedures.

Analysis Tissue Storage solution Storage container Storage temperature 

Genetics epidermis 30% DMSO saturated

with NaCl or 90% ethanol 

Glass or polypropylene 

vial 

Room temperature for up to 3 

months or frozen at –20°C. 

(Frozen at –20°C without 

preservative is best) 

Cell culture Epidermis 1)Culture media

or 

2)Freezing culture media 

polypropylene tube or 

cryotube 

1) -4°C for up to 1 week 

or 

2)-20°C, -80°C or liquid nitrogen, 

according to freezing media 

requirements. 

Stress 

responsive 

proteins (SRP) 

Epidermis None Glass or polypropylene 

vial 

Frozen -80°C 

SRP expression Epidermis None polypropylene vial Liquid nitrogen (or -80°C for 

short-term storage) 

Stable isotope epidermis or

blubber 

None Glass or polypropylene 

vial 

Frozen -20°C 

Cytochrome

P450 –

enzymatic

activities

epidermis and

blubber interface 

None polypropylene vial Liquid nitrogen (or -80°C for shortterm storage) 

Cytochrome

P450 – Gene 

expression

epidermis and

blubber interface 

1)None 

or 

2)©RNAlater solution 

polypropylene vial 1)Liquid nitrogen (or -80°C for 

short-term storage) or 

2)-4°C for 24hr followed by -80°C 

to -20C 

Cytochrome

P450 –

Immunohistoche

mistry

epidermis and

blubber interface 

10% neutral buffered 

formalin 

Glass or polypropylene 

vial 

Room temperature 

Chemistry – 

Contaminant 

burden

Blubber None Ultraclean glass vial Frozen -80°C to -20°C 

Fatty acids Blubber None Glass or polypropylene 

vial 

Frozen -20°C 

Hormones Blubber None Glass vial Frozen -80°C to -20°C 
Page 28

covery Plan), IUCN (need for global Red List assessment,

regional assessment of Mediterranean population), the IWC

(not an immediate priority, but some interest in the medium

to long term), and the HMAP project of the Census of Marine Life. The Department of the Environment and Heritage

in Australia has signaled its interest by commissioning a

pilot study of sperm whales in 2005 (Item 10.9). Japan has

an ongoing interest in sperm whale research in the North

Pacific and Antarctic, the former through JARPN-II (Item

10.4), the latter through JARPA and the IWC’s IDCR/SOWER

project (Item 10.10). The Mediterranean population of sperm

whales is a high priority of ACCOBAMS (Item 10.2). The

U.S. Minerals Management Service has a strong present

interest and likely will have an even stronger interest in the

future as oil and gas development moves into deeper water

off the continental shelf (Item 10.1). There is interest in New

Zealand, mainly related to whalewatching at Kaikoura (Item

10.7). As mentioned in Item 9.3, Alaskan longline fishermen

and the North Pacific Fisheries Management Council have a

strong interest in sperm whale status and behavior on a local

or regional level, as does the North Pacific Research Board.

11.7.2 Cooperative Projects

A number of specific proposals for collaboration were

identified and discussed. Ohsumi observed that because

each country has its own policies regarding EEZ access,

cooperative programs are needed to carry out research on

an appropriate scale for a wide-ranging species like the sperm

whale. Abundance surveys conducted under the auspices

of the IWC and the North Atlantic Marine Mammal Commission provide examples.

11.7.2.1 Global Inventory of Photo-

 Identification Data

A global inventory of photo-identification data is

needed. It is important that formal collaborations be established that include licensing agreements. The linking of catalogs greatly enhances their value.

Existing catalogs of sperm whale photographs and data

include the following:

• International Fund for Animal Welfare, NAMSC (see

Item 5.2) (contact: Tim Lewis); MS-Access based; covers Mediterranean Sea and North Atlantic

• Dalhousie University (contact: Hal Whitehead); covers eastern Pacific from Baja California to central Chile;

has own matching routine for digital photographs; being consolidated with NAMSC catalog

• R. Hucke-Gaete in Chile

• Center for Coastal Studies (contact: Nathalie Jaquet);

Gulf of California

• Southwest Fisheries Science Center (contacts: Jay

Barlow); eastern North Pacific

• Ocean Alliance, Odyssey catalog (contact: Iain Kerr);

numerous regions

• University of Otago (contact: Steve Dawson); Kaikoura,

N.Z., region and Tonga

• University of Alaska Southeast (contact: Jan Straley);

Gulf of Alaska

• Southeast Fisheries Science Center (contact: Lance

Garrison); a small regional catalog

• Europhlukes (see Item 5.2) (contact: Jonathan Gordon);

currently looking for a home base; online database and

catalogs; other tools developed or under development;

has useful structure for linking programs

• Cascadia (contact: www.cascadiaresearch.org/); North

Pacific

• National Marine Mammal Laboratory in Seattle (contact: Sally Mizroch); a small catalog

• Jonathan Gordon holds some old collections from Sri

Lanka

• Benjamin Kahn of APEX Environmental in Cairns,

Queensland, has a South Pacific/Indian Ocean collection.

11.7.2.2 Global Inventory of Tissue Collections

A similar global inventory of tissue collections, essentially a continuation and elaboration of what was described

in CARP/PS&M/1, is also needed. Again, it is important to

emphasize the value of formal collaborations. Moreover, it

is important to recognize that many tissue samples potentially have multiple research uses beyond genetic analyses

(e.g., contaminants, isotopes). Also, teeth (including those

in museum collections, with associated locality data) are an

under-recognized potential source of DNA.

Existing tissue collections include the following:

• Southwest Fisheries Science Center (contact: Sarah

Mesnick); North Pacific emphasis but global

• Cambridge University, UK (contact: Bill Amos); Azores

• University of Durham, UK (contact: Rus Hoelzel); northern Gulf of Mexico

• Centro Interdisciplinario de Ciencias Marinas – Instituto

Politécnico Nacional (contact: Diane Gendron); Gulf of

California

• Dalhousie University (contact: H. Whitehead): mainly

Pacific

• Ocean Alliance (contact: Celine Godard); numerous regions

• University of Auckland (contact: Scott Baker); small

collection mainly South Pacific

• Groupe de Recherche sur les Cétacés, Antibes, France

(contact: Violaine Drouot); Mediterranean

• National Research Institute of Far Seas Fisheries,

Shizuoka, Japan (contact: Hidehiro Kato); large num-
Page 29

bers of tissues (including teeth) from commercial whaling, Antarctic and North Pacific

• Institute of Cetacean Research, Tokyo (contact: Seiji

Ohsumi); large numbers of tissues (including teeth) from

commercial whaling, Antarctic and North Pacific

• University of Uppsala, Sweden

11.7.2.3 Global Inventory of Coda Repertoires

Another area of potential collaboration is in consolidating and sharing coda recordings. An initiative is already

underway, coordinated by the University of St. Andrews

(Gordon) and Dalhousie University (Whitehead), to examine dialect differences in relation to population structure.

Additional collections of coda recordings are know to be

held by Ocean Alliance, Groupe de Recherche sur les

Cétacés, University of Otago, and Woods Hole Oceanographic Institution. Garrison also noted that there may be

some useful coda repertoires, unrecognized and unused, in

the more general audio recordings held by the Southeast

Fisheries Science Center.

11.7.2.4 National or International Database of

 Dive Profiles

Miller called the workshop’s attention to the fact that a

consolidated database of pinniped dive profiles is being

developed, and he suggested that a similar initiative be

considered for sperm whales.

11.7.2.5 Strandings

There are many networks around the world engaged in

responding to whale strandings, and it was agreed that at a

minimum, stranded (or bycaught) sperm whales represented

a potential source of teeth, other hard parts, and at least

some soft-tissue samples. Costly responses to sperm whale

stranding events, however, require a coherent and welljustified research need. The workshop encouraged relevant

agencies to collect and distribute tissues to appropriate

researchers. Mass strandings of fresh animals, especially

any that involve female sperm whales, are of exceptional

interest and potential importance from a scientific perspective.

A tentative list of items that should be collected from a

stranded sperm whale would include (most important items

are in boldface):

• Sex

• Lengths (total body, dorsal fin to blowhole, fluke width)

• Skin sample

• Tooth (as unworn as possible, e.g., front mandibular)

• Stomach contents

• Ovaries

• Photograph of flukes

• Blubber sample

• Sample of liver

• Check if lactating

• Check if pregnant

• An eyeball

• Skin and/or internal tissue for cell culture (fresh animals

only)

• Note any evidence of human interactions (e.g., scars,

peduncle photograph).

11.7.2.6 Sharing of Tools and Technology

The workshop encouraged the sharing of research tools

and technology and noted that the International Fund for

Animal Welfare had set an exemplary standard in this regard, particularly with respect to acoustic survey equipment and techniques.

11.7.2.7 Platforms of Opportunity

In a general way, oceanographic and fishery research

cruises offer potential for collecting data on sperm whales

and their prey. The workshop encouraged this type of collaboration whenever and wherever possible. Gunnlaugsson

provided an example from the North Atlantic, where redfish

surveys are carried out regularly in a wide area southwest

of Iceland, including the Mid-Atlantic Ridge south to 55oN.

Cetacean observers operated with good success on the

two Icelandic vessels participating in these surveys in 2001.

No observers were onboard the other two participating vessels. The value of observations on these platforms is enhanced by the collection of data on multiple ecological variables. This work is conducted under the ICES Planning

Group on Redfish Stocks, which includes Germany, Norway, Russia, and Iceland.

Similarly, Waring pointed out that the MARECO project

of the Census of Marine Life included marine mammal observers aboard recent oceanographic and fishery exploratory studies on the Mid-Atlantic Ridge. Sperm whales were

the most frequently sighted cetaceans.

Straley pointed out the value of forging collaborations

with coastal fishing fleets and fishery observer programs.

This has been demonstrated to some extent in southeastern Alaska, where fishery interactions with sperm whales

have provided a strong motivation on the fishermen’s part.

She stressed the importance of standard forms and protocols for data collection, and this applies to all platform-ofopportunity programs.

Whalewatching operations also offer potential for data

collection of various kinds. The workshop encouraged sperm
Page 30

whale scientists to explore the possibilities of cooperating

with such operations, e.g., in Dominica, the Azores, Norway, and Kaikoura (some of this potential has already been

realized in the Azores and Norway).

11.7.2.8 Population Modeling Working Group

Given the importance, and the difficulties, of modeling

sperm whale populations, it was recommended that a working group of experts be formed to develop, test, and refine

appropriate models in a collaborative manner.

11.7.3 Research Coordination Mechanisms

It was agreed that a follow-up workshop to the present

one should be convened in approximately two years. Also,

it was agreed that an e-mail consultation should be organized among participants approximately in one year’s time,

to check progress on items discussed and recommended

by the workshop.

12. TOP PRIORITIES FOR FUTURE

 WORK

The workshop agreed that the following areas of research should be given highest priority:

• Subdivide the global sperm whale population into a series of provisional units for analyses (hypothesis-testing) and initial management.

• Obtain and analyze additional data on female survival

for at least several small populations.

• Facilitate more detailed exploration of differential depletion (male vs. female) by stratifying catch data by sex

and investigating the breeding system more closely (to

evaluate the role of large “roving” males), e.g., through

behavior studies in semi-enclosed areas.

• Improve catch history by accounting for 18th century

removals, resolving the problem of misreporting in the

North Pacific post-World War II, and increasing spatial

resolution.

• Carry out abundance surveys in additional areas, especially in the Atlantic and Indian Oceans.

• Continue to refine estimates of g(0).

• Use existing data to refine modeling approaches (e.g.,

extrapolation methods), investigate alternative values

of rmax (rate of increase), and test sensitivity to different

input parameters (e.g., density dependence).

Ideally, in the course of that research, there should be

regular and substantive interaction between modelers and

the field researchers involved in data collection.

Following the workshop, the conveners and chairman

prepared a list of research tasks identified by workshop

participants (Table 2). These tasks were regarded as desirable steps to be taken in advance of, or as part of, an indepth assessment of sperm whale populations. The tasks

were grouped by topic, roughly consistent with the various

subjects covered in the workshop agenda. Numbering of

the tasks was arbitrary and not meant to reflect order of

priority. Nevertheless, those tasks of highest priority (as

the editors interpreted the discussion) are highlighted. It

was intended that priorities should be determined by the

needs of modeling, as indicated earlier under this agenda

item. It was recognized that completion of some of the tasks

in Table 2 could be achieved by discrete, one-time efforts,

while others would require more general, ongoing efforts

by several different researchers or research teams.
Page 31

Table 2. Research tasks by general category to be addressed in preparation for in-depth assessment of sperm whale 

populations. Those in boldface type should be given highest priority and initiated as soon as possible. See text for 

elaboration. 

Category Number Description 

 

Pop. Structure 1 Provisionally identify units to test for discreteness.

Pop. Structure 2 Continue and expand genetic analyses, integrated with data on vocal clans as possible. 

Pop. Structure 3 Conduct comprehensive analysis and synthesis of Discovery mark program, including USSR 

data. 

Pop. Structure 4 Conduct global inventory of photo-identification data, linking catalogs to the maximal extent 

possible. (Also applies to Abundance) 

Pop. Structure 5 Conduct global inventory of tissue collections. 

Pop. Structure 6 Conduct global inventory of coda repertoires. 

Pop. Structure 7 Establish unified, comprehensive database on sperm whale morphometrics.

Pop. Structure 8 Refine provisional population units. 

 

Abundance 1 Conduct global inventory of dive profiles. 

Abundance 2 Refine estimates of g(0). 

Abundance 3 Improve automation of photograph matching; evaluate use of dorsal fins and other features 

besides the flukes in photo-identification of individuals. 

Abundance 4 Improve methods for estimating group size acoustically, especially for large groups (up

to 30 individuals).

Abundance 5 Develop consensus on relative merits of acoustic and visual surveys. 

Abundance 6 Evaluate methods of extrapolating densities to unsurveyed areas. 

Abundance 7 Conduct additional surveys in selected areas. 

 

Human 

Interactions 

1 Improve estimates of whaling removals in 18th and 19th centuries, by region and sex, 

including estimates of statistical precision.

Human 

Interactions 

2 Resolve problems surrounding misreported and under-reported catches in North Pacific 

during 20th century: USSR, Japan.

Human 

Interactions 

3 Improve reporting and estimation of incidental mortality of sperm whales in fisheries,

especially drift gillnets. 

Human 

Interactions 

4 Obtain additional measures of chemical contaminants in sperm whale tissues and improve 

understanding of effects, including dose-response relationships whenever possible. 

Human 

Interactions 

5 Get more and better data (both qualitative and quantitative) on sperm whale interactions with 

longline fisheries. 

Human 

Interactions 

6 Determine effects of human-induced noise on behavior and ecology of sperm whales, 

especially in relation to oil and gas industry.

 

Life History 1 Compare observed calf proportions in different study areas and refine understanding of 

calving rate and maximal potential rate of increase. 

Life History 2 Determine function of codas. 

Life History 3 Determine population effects of differential depletion by sex.

Life History 4 Obtain more precise estimates of adult female survival. 

 

Modeling 1 Establish population modeling working group to ensure interaction among researchers.

Modeling 2 Refine modeling approaches – e.g., alternative values of rmax, sensitivity to input 

parameters. 

 

Coordination 1 Organize e-mail consultation. 

Coordination 2 Conduct follow-up workshop in two years to review progress. 

Coordination 3 Determine when sufficient information is available to allow in-depth assessment of sperm

whales. 
Page 32

13. REFERENCES CITED

Allison, C. and Smith, T.D. 2004. Progress on the construction of a comprehensive data base on twentieth century whaling catches. Paper SC/56/O27 presented to

the IWC Scientific Committee, Sorrento, Italy, July 2004.

[Available from the office of the IWC Secretariat:

www.iwcoffice.org]

Bannister, J.L., Taylor, S. and Sutherland, H. 1981. Logbook

records of 19th century American sperm whaling: a report on the 12 month project, 1978-79. Report of the

International Whaling Commission 31:821-833.

Barlow, J. 1995. The abundance of cetaceans in California

waters. Part I: Ship surveys in summer and fall of 1991.

Fishery Bulletin 93:1-14.

Barlow, J. 2003a. Perspective on models of sperm whale population dynamics. Paper SC/55/O22 presented to the IWC

Scientific Committee, Berlin, May 2003. 3pp. [Available

from the office of the IWC Secretariat:

www.iwcoffice.org]

Barlow, J. 2003b. Preliminary estimates of the abundance of

cetaceans along the U.S. west coast: 1991-2001. Administrative Report LJ-03-03, available from Southwest

Fisheries Science Center, 8604 La Jolla Shores Dr., La

Jolla CA 92037. 31pp.

Barlow, J. 2003c. Cetacean abundance in Hawaiian waters

during summer/fall of 2002. Administrative Report LJ03-13, available from Southwest Fisheries Science Center, 8604 La Jolla Shores Dr., La Jolla CA 92037. 20pp.

Barlow, J. and Clapham, P.J. 1997. A new birth-interval approach to estimating demographic parameters of humpback whales. Ecology 78:535-546.

Barlow, J. and Rankin, S. 2004. Estimates of the percentage

of sperm whales missed on combined visual and acoustic surveys in the eastern Pacific Ocean. Journal of the

Acoustical Society of America 116:2588. [Abstract]

Barlow, J. and Taylor, B.L. 2001. Estimates of large whale

abundance off California, Oregon, Washington, and

Baja California based on 1993 and 1996 ship surveys.

Administrative Report LJ-01-03. National Marine Fisheries Service, Southwest Fisheries Science Center, P.O.

Box 271, La Jolla, California 92038.

Barlow, J. and Taylor, B.L. 2005. Estimates of sperm whale

abundance in the northeastern temperate Pacific from a

combined acoustic and visual survey. Marine Mammal

Science 21(3):429-445.

Barnes, R.H. 1996. Sea hunter of Indonesia: fishers and

weavers of Lamalera. Clarendon Press, Oxford, UK.

Best, P.B. 1974. . Pp. 53-81 in W.E. Schevill (ed.), The whale

problem: a status report. Harvard University Press, Cambridge, Massachusetts

Best, P.B. 1979. Social organization in sperm whales,

Physeter macrocephalus. Pp. 227-289 in H.E. Winn and

B.L. Olla (eds.), Behavior of marine animals: current

perspectives in research. Vol. 3: Cetaceans. Plenum

Press, New York.

Best, P.B. 1983. Sperm whale stock assessments and the relevance of historical whaling records. Report of the International Whaling Commission (Special Issue) 5:41-55.

Best, P.B., Canham, P.A.S. and MacLeod, N. 1984. Patterns

of reproduction in sperm whales, Physeter macrocephalus. Report of the International Whaling Commission

(Special Issue) 6:51-79.

Best, P.B. and Ross, G.J.B. 1989. Whales and whaling. pp

315-338 in Oceans of life off southern Africa. Vlaeberg

Publishers, Cape Town. 380pp.

Bond, J. 1999. Genetical analysis of the sperm whale using

microsatellites. Ph.D. dissertation, Cambridge University, Cambridge, UK.

Brown, S.G. 1977. Whale marking: a short review. Pp. 569-

581 in M. Angel, ed., A voyage of discovery. Pergamon

Press, Oxford.

Brownell, R.L., Jr., Yablokov, A.V. and Zemsky, V.A. 2000.

USSR pelagic catches of North Pacific sperm whales,

1949-1979: conservation implications. Pp. 123-130 in A.V.

Yablokov and V.A. Zemsky (eds.), Soviet whaling data

(1949-1979). Center for Russian Environmental Policy,

Moscow.

Chessum, C. 1992. Distribution, population structure, social organisation, and behaviour of sperm whales off

the Kaikoura Coast. Unpubl. MSc thesis, University of

Otago, Dunedin, New Zealand. 93pp.

Childerhouse, S.J., Dawson, S.M., and Slooten, E. 1995.

Abundance and seasonal residence of sperm whales at

Kaikoura, New Zealand. Canadian Journal of Zoology

73:723-731.

Childerhouse, S.J., Dawson, S.M., and Slooten, E. 1996.

Stability of fluke marks used in individual photo-identification of sperm whales at Kaikoura, New Zealand.

Marine Mammal Science 12(3):447-451.

Clapham, P.J. and Baker, C.S. 2002. Modern whaling. pp.

1328-1332 in W.F. Perrin, B. Würsig and J.G.M.

Thewissen (eds.), Encyclopedia of Marine Mammals.

Academic Press, San Diego, California.

Christal, J., Whitehead, H. and Lettevall, E. 1998. Sperm

whale social units: variation and change. Canadian Journal of Zoology 76:1431-1440.

Dawson, S.M., Chessum, C.J., Hunt, P., and Slooten, E. 1995.

An inexpensive, stereo-photographic technique to measure sperm whales from small boats. Report of the International Whaling Commission 45: 431-436.

Donovan, G.P. 1991. A review of IWC stock boundaries.

Report of the International Whaling Commission (Special Issue) 13:39-68.

Douglas, L.A. 2000. Click Counting: An Acoustic Censusing

Method for Estimating Sperm Whale Abundance.

Unpub. M.Sc. Thesis, University of Otago, Dunedin,

New Zealand.

Drouot, V., Gannier, A. and Goold, J.C. 2004a. Diving and

feeding behaviour of sperm whales (Physeter macrocephalus) in the northwestern Mediterranean Sea.

Aquatic Mammals 30(3): 419-426.
Page 33

Drouot, V., Bérubé, M., Gannier, A., Goold, J.C., Reid, R.J.

and Palsbøll, P.J. 2004b. A note on genetic isolation of

Mediterranean sperm whales (Physeter macrocephalus) suggested by mitochondrial DNA. Journal of

Cetacean Research and Management 6(1):29–32.

Dufault, S. Whitehead, H. 1995. The geographic stock structure of female and immature sperm whales in the South

Pacific. Report of the International Whaling Commission 45:401-405.

Engelhaupt, D. 2004. Molecular ecology of the sperm whale

in the Gulf of Mexico, Mediterranean Sea and North

Atlantic. Ph.D. thesis, Durham University, UK.

Evans, K., Hindell, M.A., Robertson, K., Lockyer, C. and

Rice, D. 2002. Factors affecting the precision of age

determination of sperm whales (Physeter macrocephalus). Journal of Cetacean Research and Management

4(2):193-201.

Frantzis, A. 1998. Does acoustic testing strand whales?

Nature 392:29.

Gaskin, D.E., and Cawthorn, M.W. 1967. Diet and feeding

habit of the sperm whale (Physeter catodon) in the

Cook Strait region of New Zealand. New Zealand Journal of Marine and Freshwater Research 2:156-179.

Godard, C., Smolowitz, R.M., Wilson, J.Y., Payne, R.S., and

Stegeman, J.J. 2004. Induction of cetacean cytochrome

P4501A1 by ß-naphthoflavone exposure of skin biopsy

slices. Toxicological Sciences 80:268-275.

Gordon, J. C. D. 1990. A simple photographic technique for

measuring the length of whales from boats at sea. Report of the International Whaling Commission 40:581-

588.

Gormley, A. 2002. Use of mark-recapture for estimating the

abundance of four marine mammal species in New

Zealand. Unpubl. M.Sc. thesis, University of Otago,

Dunedin, New Zealand.

Grady, D. 1982. The Perano whalers of Cook Strait: 1911-

1964. A.H. and A.W. Reed Ltd., Wellington, New

Zealand. 238pp.

Gunnlaugsson, Th. 2004. Comparison of sighting rates from

NASS and other dedicated cetacean vessel effort around

Iceland during 1982-2003. IWC SC/56/05. (To be published in NAMMCO Scientific Publications 6)

Gunnlaugsson, Th., Víkingsson, G.A., Pike, D.G., Desportes,

G., Mikkelsen, B. and Bloch, D. 2002. Combined linetransect and cue-count estimate of sperm whale abundance in the North Atlantic, from Icelandic and Faroese

NASS-2001 shipboard surveys. Paper SC/54/O8 presented to the IWC Scientific Committee, Shimonoseki,

Japan, April 2002. [Available from the office of the IWC

Secretariat: www.iwcoffice.org] (To be published in

NAMMCO Scientific Publications 6)

Haase, B. and Félix, F. 1994. A note on the incidental mortality of sperm whales (Physeter macrocephalus) in Ecuador. Report of the International Whaling Commission

(Special Issue) 15:481-483.

Hastie, G.D., Swift, R.J., Gordon, J.C.D., Slesser, G. and Turrell,

W.R. 2003. Sperm whale distribution and seasonal density in the Faroe Shetland Channel. Journal of Cetacean Research and Management 5(3):247-252.

Hegarty, R. H. 1959. Returns of whaling vessels sailing from

American ports. A continuation of Alexander Starbuck’s

“history of the American whale fishery” 1876-1928. Old

Dartmouth Historical Society and Whaling Museum,

New Bedford, Massachusetts. 58 pp.

Hiby, A. and Lovell, P. 1989. Acoustic survey techniques

for sperm whales. Paper SC/41/Sp3 presented to the

IWC Scientific Committee, San Diego, June 1989. [Available from the office of the IWC Secretariat:

www.iwcoffice.org]

Hope, P.L. and H. Whitehead. 1991. Sperm whales off the

Galápagos Islands from 1830-50 and comparisons with

modern studies. Report of the International Whaling

Commission 41:273-86.

Ivashin, M.V. 1967. Whale globe-trotter. Priroda (Moscow)

8:105-107.

IWC. 2005. Report of the Scientific Committee. Journal of Cetacean Research and Management 7 (Supplement):1-391.

Jaquet, N., Dawson, S.M. and Douglas, L. 2001. Vocal behavior of male sperm whales: why do they click? Journal of the Acoustical Society of America 109(5):2254-

2259.

Jaquet, N., Dawson, S.M. and Slooten, E. 2000. Seasonal

distribution and diving behaviour of male sperm whales

off Kaikoura: foraging implications. Canadian Journal

of Zoology 78:407-419.

Jaquet, N., Whitehead, H. and Lewis, M. 1996. Coherence

between 19th century sperm whale distributions and

satellite-derived pigments in the tropical Pacific. Marine Ecology Progress Series 145:1-10.

Jepson, P.D., Arbelo, M. et al. 2003. Was sonar responsible

for a spate of whale deaths after an Atlantic military

exercise? Nature 425:575–576.

Kasuya, T. 1999. Examination of the reliability of catch statistics in the Japanese coastal sperm whale fishery. Journal of Cetacean Research and Management 1:109-122.

Kasuya, T. 2003. Potential for improvement of 20th century

sperm whale catch data. Paper SC/55/O14 presented to

the IWC Scientific Committee, Berlin, May 2003. [Available from the office of the IWC Secretariat:

www.iwcoffice.org]

Kasuya, T. and Miyashita, T. 1988. Distribution of sperm

whale stocks in the North Pacific. Scientific Reports of

the Whales Research Institute 39:31-75.

Kirkwood, G.P. and Bannister, J.L. 1980. Revised abundance

indices for sperm whales off Albany, Western Australia. Report of the International Whaling Commission

(Special Issue) 2:89-91.

Laist, D.W., Knowlton, A.R., Mead, J.G., Collet, A.S. and

Podesta, M. 2001. Collisions between ships and whales.

Marine Mammal Science 17(1):35-75.

Leaper, R., Gordon, J. and Chappell, O. 1992. The development of practical techniques for surveying sperm whale

populations acoustically. Report of the International

Whaling Commission 42:549-560.
Page 34

Leaper, R., Gillespie, D. and Papastavrou, V. 2000. Results of

passive acoustic surveys for odontocetes in the Southern Ocean. Journal of Cetacean Research and Management 2(3):187-196.

Leaper, R., Gillespie, D., Gordon, J. and Matthews, J. 2003.

Abundance assessment of sperm whales. Paper SC/55/

O13 presented to the IWC Scientific Committee, Berlin,

May 2003. [Available from the office of the IWC Secretariat: www.iwcoffice.org]

Lettevall, E., Lindhard, M. et al. 1993. Sperm whale photoidentification and length-measuring project. European

Research on Cetaceans [Abstracts] 7:155.

Lund, J.N. 2001. Whaling Masters and Whaling Voyages

Sailing from American Ports: A Compilation of

Sources. New Bedford Whaling Museum, New Bedford,

Massachusetts; Kendall Whaling Museum, Sharon,

Massachusetts; and Ten Pound Island Book Co.,

Gloucester, Massachusetts.

Lyrholm, T., Leimar, O. and Gyllensten, U. 1996. Low diversity and biased substitution patterns in the mitochondrial DNA control region of sperm whales: implications

for estimates of time since common ancestry. Molecular Biology and Evolution 13:1313-1326.

Lyrholm, T., Leimar, O., Jahanneson, B. and Gyllensten, U.

1999. Sex-biased dispersal in sperm whales: contrasting mitochondrial and nuclear genetic structure of global populations. Proceedings of the Royal Society of

London B 266:347-354.

Martin, A.R. 1982. A link between the sperm whales occurring off Iceland and in the Azores. Mammalia 46:259-

260.

Matthews, J.N., Steiner, L. et al. 2001. Mark-recapture analysis of sperm whale (Physeter macrocephalus) photoidentification data from the Azores (1987-1995). Journal

of Cetacean Research and Management 3(3):219-226.

Mesnick, S.L. 2001. Genetic relatedness in sperm whales:

evidence and cultural implications. Behav. and Brain

Sci. 24:346-347.

Mesnick, S.L., Evans, K., Taylor, B.L., Hyde, J., EscorzaTreviño, S. and Dizon, A.E. 2003. Sperm whale social

structure: why it takes a village to raise a child. pp. 170-

174 in F.B.M. de Waal and P.L. Tyack, eds., Animal social complexity: intelligence, culture and individualized

societies. Harvard University Press, Cambridge, Massachusetts.

Miller, P.J.O., Johnson, M.P. and Tyack, P.L. 2004a. Sperm

whale behaviour indicates the use of echolocation click

buzzes ‘creaks’ in prey capture. Proceedings of the

Royal Society of London B 271:2239-2247.

Miller, P.J.O., Johnson, M.P., Tyack, P.L. and Terray, E.A.

2004b. Swimming gaits, passive drag and buoyancy of

diving sperm whales Physeter macrocephalus. Journal

of Experimental Biology 207:1953-1967.

Mitchell, E. 1975. Preliminary report on Nova Scotian fishery for sperm whales (Physeter catodon). Report of the

International Whaling Commission 25:226-235.

Miyashia, T., Kato, H. and Kasuya, T. 1995. Worldwide map

of cetacean distribution based on Japanese sightings

data. National Research Institute of Far Seas Fisheries,

Shizuoka, Japan.

Moore, M.J. and Early, G. A. 2004. Cumulative sperm whale

bone damage and the bends. Science 306(5705):2215-

2215.

Moore, M.J. and Early, G.A. 2005. In response to Rothschild’s

suggestion. Science 308:631-632.

Moore, M.J., Miller, C.A., Morss, M.S., Arhur, R., Lange,

W.A., Prada, K.G., Marx, M.K. and Frey, E.A. 2001. Ultrasonic measurement of blubber thickness in right

whales. Journal of Cetacean Research and Management (Special Issue) 2:301-309.

Mullin, K.D., Engelhaupt, D., Cates, C.E. and Barros, N.B.

2003. Sperm whale research in the Gulf of Mexico. Paper SC/55/O15 presented to the IWC Scientific Committee, Berlin, May 2003. 3pp. [Available from the office

of the IWC Secretariat: www.iwcoffice.org]

National Research Council. 2005. Marine mammal populations and ocean noise: determining when noise causes

biologically significant effects. National Academies

Press, Washington, D.C.

Norris, K.S. and Harvey, G.W. 1972. A theory for the function of the spermaceti organ of the sperm whale

(Physeter macrocephalus). pp. 397-419 in S.R. Galler,

K. Schmidt-Koenig, G.J. Jacobs, and R.E. Belleville, eds,

Animal orientation and navigation. Special Publication,

National Aeronautics and Space Administration, Washington D.C.

Notarbartolo di Sciara, G. 1990. A note on the cetacean incidental catch in the Italian driftnet swordfish fishery,

1986-1988. Report of the International Whaling Commission 40:459-460.

Ohsumi S., 1977. Age-length key of the male sperm whale in

the North Pacific and comparisons of growth curves.

Report of the International Whaling Commission 27:295-

300.

Omura, H. and Ohsumi, S. 1964. A review of Japanese whale

marking in the North Pacific to the end of 1962, with

some information on marking in the Antarctic. Norsk

Hvalfangst-tidende 53:90-112.

Ohsumi, S. and Masaki, Y. 1975. Japanese whale marking in

the North Pacific, 1963-1972. Bulletin of the Far Seas

Fisheries Research Laboratory, Shimizu 12:171-219.

Reeves, R.R. and Smith, T.D. In press. A taxonomy of world

whaling: operations, eras, and data sources. In J.A.

Estes, R.L. Brownell, Jr., D.P. DeMaster, D.F. Doak, and

T.M. Williams (eds.), Whales, whaling, and ocean ecosystems. University of California Press, Berkeley.

Rendell, L. and Whitehead, H. 2003. Vocal clans in sperm

whales (Physeter macrocephalus). Proceedings of the

Royal Society London B 270:225-231.

Rhinelander, M.Q. and Dawson, S.M. 2004. Measuring sperm

whales from their clicks: stability of inter-pulse intervals and validation that they indicate whale length.
Page 35

Journal of the Acoustical Society of America

115(4):1826-1831.

Rice, D.W. 1989. Sperm whale Physeter macrocephalus

Linnaeus, 1758. pp. 177-233 in S.H. Ridgway and R.

Harrison (eds.), Handbook of marine mammals volume

4: river dolphins and the larger toothed whales. Academic Press, London.

Rice, D.W. 1998. Marine mammals of the world: systematics

and distribution. Society for Marine Mammalogy, Special Publication No. 4, 231pp.

Richard, KR., Dillon, M.C., Whitehead, H. and Wright, J.M.

1996. Patterns of kinship in groups of free-living sperm

whales (Physeter macrocephalus) revealed by multiple

molecular genetic analyses. Proceedings of the National

Academy of Sciences of the USA. 93:8792-8795.

Richter, C., Dawson, S.M., and Slooten, E. 2003. Sperm whale

watching at Kaikoura, New Zealand: effects of current

activities on surfacing and vocalisation patterns. Department of Conservation, Wellington, N.Z. Science for

Conservation 219, 78pp.

Roman, J. and Palumbi, S. 2003. Whales before whaling in

the North Atlantic. Science 301:508-510.

Rothschild, B.M. 2005. What causes lesions in sperm whale

bones? Science 308:631.

Smith, T.D. and Reeves, R.R. (Eds.). 2003. Design of a program of research on sperm whale catch history: results

of a workshop. Available: http://www.cmrh.dk/

Cachalot.pdf

Starbuck, A. 1878. History of the American Whale Fishery

from its Earliest Inception to the Year 1876. Report of

the U.S. Fish Commission 4, 1875-6, Appendix A.

Tamura, T., Kubodera, T., Ohizumi, H., Konishi, K., Isoda, T.

and Fujise, Y. 2004. Food habits of sperm whales based

on JARPN II (2000-03). In Government of Japan: some

considerations of the feasibility components of the

JARPN II research plan. Appendix 4 of Document SC/

56/O2, 10 pp. Presented to the IWC Scientific Committee, Sorrento, Italy, June 2004. [Available from the office of the IWC Secretariat: www.iwcoffice.org]

Thode, A., Mellinger, D.K., Stienessen, S., Martinez, A., and

Mullin, K. 2002. Depth-dependent acoustic features of

diving sperm whales (Physeter macrocephalus) in the

Gulf of Mexico. Journal of the Acoustical Society of

America112:308-321.

Thode, A.2004. Tracking sperm whale (Physeter macrocephalus) dive profiles using a towed passive acoustic array. Journal of the Acoustical Society of America

116:245-253.

Tillman, M.F. and Breiwick, J.M. 1983. Estimates of abundance for the western North Pacific sperm whale based

upon historical whaling records. Report of the International Whaling Commission (Special Issue) 5:257-269.

Tormosov, D., Brandao, A. and Best, P.B. 2003. Evaluating

Southern Hemisphere sperm whale foetal records for

evidence of regional seasonality in breeding. Paper SC/

55/O20 presented to the IWC Scientific Committee,

Berlin, May 2003. [Available from the office of the IWC

Secretariat: www.iwcoffice.org]

Townsend, C.H. 1935. The distribution of certain whales as

shown by the logbook records of American whaleships.

Zoologica 19:1-50.

Tyack, P., Gordon, J. and Thompson, D. 2004. Controlled

exposure experiments to determine the effects of noise

on large marine mammals. Marine Technology Society

Journal 37(4):41-53.

Wade, P.R. and Gerrodette, T. 1993. Estimates of cetacean

abundance and distribution in the eastern tropical Pacific. Report of the International Whaling Commission

43:477-493.

Weilgart, L.S. and Whitehead, H. 1997. Group-specific dialects and geographical variation in coda repertoire in

South Pacific sperm whales. Behavioral Ecology and

Sociobiology 40:277-285.

Whitehead, H. 1995. Status of Pacific sperm whale stocks

before modern whaling. Report of the International

Whaling Commission 45:407-412.

Whitehead, H. 2001. Analysis of animal movement using

opportunistic individual identifications: application to

sperm whales. Ecology 82:1417-1432.

Whitehead, H. 2002. Estimates of the current global population size and historical trajectory for sperm whales. Marine Ecology Progress Series 242:295-304.

Whitehead, H. 2003. Sperm whales: social evolution in the

ocean. University of Chicago Press, Chicago, Illinois.

Whitehead, H., Christal, J. and Dufault, S. 1997. Past and

distant whaling and the rapid decline of sperm whales

off the Galapagos Islands. Conservation Biology

11:1387-1396.

Whitehead, H., Rendell, L., Osborne, R., and Wursig, B.

2004. Culture and conservation of non-humans with

reference to whales and dolphins: review and new directions. Biological Conservation 120:431-441.

Yablokov, A.V. and Zemsky, V.A. (eds.). 2000. Soviet whaling data (1949-1979). Center for Russian Environmental

Policy, Moscow.

Yablokov, A.V., Zemsky, V.A., Mikhalev, Y.A., Tormosov,

V.V. and Berzin, A.A. 1998. Data on Soviet whaling in

the Antarctic in 1947-1972 (population aspects). Russian Journal of Ecology 29:38-42.

Zemsky, V.A., Berzin, A.A., Mikhalyev, Yu.A. and Tormosov,

D.D. 1995. Soviet Antarctic whaling data (1947-1972).

Center for Russian Environmental Policy, Moscow.
Page 36
Page 37

ANNEX 1: LIST OF PARTICIPANTS

Bando, Takeharu

Institute of Cetacean Research

4-5, Toyomi-cho, Chuo-ku,

Tokyo, 104-0055, JAPAN

bando@cetacean.jp

Baker, Kyle

National Marine Fisheries Service

263 13th Ave S

St. Petersburg, FL 33701

727-551-5789

Kyle.Baker@noaa.gov

Bannister, John

The Western Australian Museum

Francis Street

Perth, WESTERN AUSTRALIA 6000

61 89 427 2800

bannisj@compuserve.com

Barlow, Jay

SWFSC/NOAA Fisheries

8604 La Jolla Shores Drive

La Jolla, CA 92037

855-546-7178

Jay.Barlow@noaa.gov

Best, Peter B.

Mammal Research Institute

University of Pretoria

Pretoria

0002 SOUTH AFRICA

pbest@iziko.org.za

Brewer, Ciara

RUWPA

University of St. Andrews

The Observatory

Buchanan Gardens

KY16 9LZ, Fife, SCOTLAND

ciara@mcs.at-andrews.ac.uk

Chatwin, Dale

PO Box 3780

Weston Act 2611 AUSTRALIA

61 2 6252 6610

dchatwin@pcug.org.au

Clapham, Phil

AFSC/National Marine Mammal Lab

7600 Sand Point Way NE

Seattle, WA 98115

206-526-4037

Phillip.clapham@noaa.gov

Cornish, Vicki

NMFS Southeast Region

263 13th Ave S

St. Petersburg, FL 33701

727-551-5771 (as of 3/17/05)

vicki.cornish@noaa.gov

Dawson, Steve

Marine Science Dept.,

Otago University

P.O. Box 56

Dunedin, NEW ZEALAND

64 3 479 7468

steve.dawson@stonebow.otago.ac.nz

Drouot, Violaine

Groupe de Recherche sur les Cétacés

Ch. Moy. Breguières

BP 715 06633 Antibes Cedex

FRANCE

violainedr@hotmail.com

Garrison, Lance

Southeast Fisheries Science Center

75 Virginia Beach Drive

Miami, FL 33149

305-361-4488

Lance.Garrison@noaa.gov

Gillespie, Douglas

International Fund for Animal Welfare

87-90 Albert Embankment

London, SE1 7UD, UK

dgillespie@ifaw.org

Godard, Celine

USM Center for Integrated & Applied Environmental

 Toxicology

University of Southern Maine

Portland, ME 04104-9300

cgodard@usm.maine.edu

Gordon, Jonathan

SMRU

CTA777 Lab

University of St. Andrews

St. Andrews, KY16 8LB

UK

Gunnlaugsson, Thorvaldur

Marine Research Institute

ICELAND

354-823-6084

thg@hafro.is

Jaquet, Nathalie

Center for Coastal Studies

59 Commercial Street

Provincetown, MA 02567

jaquetn@coastalstudies.org

Josephson, Beth

NOAA/NMFS

166 Water Street

Woods Hole, MA 02543

508-495-2362

elizabeth.josephson@noaa.gov
Page 38

Kato, Hidehiro

Cetacean Biology Unit

National Research Institute of Far Seas Fisheries

5-7-1, Shimizu-Orido, Shizuoka 424-8633, JAPAN

Tel 81 543 36 6052

Fax 81 543 35 9642

katohide@affrc.go.jp

Kerr, Iain

Ocean Alliance

141 Weston Road

Lincoln, MA 01773

Kerr@whale.org

Lund, Judy

7 Middle Street

Dartmouth, MA USA 02748

508-996-4864

jnlund@comcast.net

Madsen, Peter T.

Woods Hole Oceanographic Inst.

Caryn House MS #44

Woods Hole, MA 02543

PMADSEN@WHOI.edu

Mesnick, Sarah

Southeast Fisheries Science Center, NOAA Fisheries

8604 La Jolla Shores Dr.

La Jolla, CA 92037

858-546-7148

Sarah.mesnick@noaa.gov

Miller, Patrick

SMRU, Gatty Marine Lab

University of St. Andrews

St. Andrews, Fife KY16 9QQ

pm29@st-andrews.ac.uk

Nicolas, John

Marine Mammal Specialist

NOAA/NMFS

Woods Hole, MA 02543

Ohsumi, Seiji

Institute of Cetacean Research

4-5 Toyomi-cho, Chuo-ku

Tokyo, 104-0055 JAPAN

Ohsumi@cetacean.jp

Pierce, Nathan D.

Protected Species Branch

NEFSC/NOAA

Woods Hole, MA 02543

Nathan.pierce@noaa.gov

Reeves, Randall

Okapi Wildlife Associates

27 Chandler Lane

Hudson, Quebec, CANADA I0P 1H0

450-458-6685

rrreeves@total.net

Smith, Daniel W.

Protected Species Branch

NEFSC/NOAA

Woods Hole, MA 02543

daniel.w.smith@noaa.gov

Smith, Tim

NEFSC

166 Water Street

Woods Hole, MA 02543

CachalotProject@gmail.com

Straley, Jan

University of Alaska Southeast

1332 Seward Ave

Sitka, AK 99835

907-747-7779

Jan.Straley@uas.alaska.edu

Thode, Aaron

SIO/UCSD

9500 Gilman Dr. MC 0238

La Jolla, CA 92093-0238

858-822-4864

thode@mpl.uscd.edu

Tyack, Peter

Biology Dept MS #44

Woods Hole Oceanographic Institution

Woods Hole, MA 02543

ptyack@whoi.edu

Waring, Gordon

NEFSC

166 Water Street

Woods Hole, MA 02543

Gordon.waring@noaa.gov

Watwood, Stephanie

Woods Hole Oceanographic Institution

Caryn House MS #44

Woods Hole, MA 02543

swatwood@whoi.edu

Whitehead, Hal

Department of Biology

Dalhousie University

Halifax, Nova Scotia

CANADA B3H 4J1

Tel 902-494-3723

Fax 902-494-3736

Hal.Whitehead@dal.ca
Page 39

ANNEX 2: AGENDA

1. Welcome

2. Review terms of reference, agenda, available documentation, and workshop logistics

3. Introduction of workshop chair and rapporteur

4. Overviews (INT)

4.1 Overview of sperm whale assessments

4.2. Overview of population models

5. Population structure and movements (PS&M)

5.1. Tagging

5.2. Individual identification

5.3. Acoustic

5.4. Morphology

5.5. Genetics

5.6. Historical evidence

6. Abundance and distribution (A&D)

6.1. Whaling records

6.2. Genetic diversity

6.3. Sighting and acoustic surveys, including dive cycle

6.4. Individual identification

7. Life history (LH)

7.1. Age determination

7.2. Vital rates

7.3. Social structure

8. Population ecology (PE)

8.1. Feeding

8.2. Diving physiology

9. Human interactions (HI)

9.1. 20th Century whaling

9.2. Pre-20th Century whaling

9.3. Interactions with fisheries and shipping

9.4. Environmental issues

10. Field Programs (FP)

10.1. Gulf of Mexico

10.2. Mediterranean

10.3. E North Pacific

10.4. W North Pacific

10.5. Western North Atlantic and Caribbean

10.6. Eastern and Central North Atlantic

10.7. South Pacific

10.8. Odyssey

10.9. Indian

10.10. Antarctic

11. Future Work

11.1. Need to understand true, underlying structure of populations

11.2. Need to obtain accurate estimates of the numbers of whales removed by whaling from each population

11.3. Need to estimate abundance for a high proportion of waters worldwide

11.4. Need to improve understanding of the demographics of population growth

11.5. Need to develop sperm whale population models

11.6. Biological significance of present-day ‘changes’

11.7. Implementing components of needed research

12. Top priorities for future work
Page 40

 ANNEX 3: LIST OF DOCUMENTS

A&D 1 Gillespie D., 

Leaper, R., 

Gordon, J. 

Acoustic Surveys for Sperm Whales - Theory and Practice

A&D 2 Thode, A. Three-dimensional Underwater Tracking of Sperm Whales 

Using Passive Acoustics 

A&D 3 FI Barlow, J., Rankin, 

S. 

Estimates of the Percentage of Sperm Whales Missed on

Combined Visual and Acoustic Surveys in the Eastern 

Pacific Ocean 

A&D 4 FI Barlow, J., Taylor,

B.L. 

Estimates of Sperm Whale Abundance in the Northeastern 

Temperate Pacific from a Combined Acoustic and Visual 

Survey 

A&D 5 FI Leaper, R., 

Gillespie, J., 

Matthews, J. 

Abundance Assessment of Sperm Whales 

A&D 6 Matsuoka, K., 

Kiwada, H., Fujise, 

Y. and Ohsumi, S. 

Distribution Pattern of Sperm Whales in the Western North

Pacific Based on Sighting Survey Data of the JARPN/ 

JARPN II between 1994 and 2004. 

A&D 7 Matsuoka, K., 

Kiwada, H., 

Hakamada, T., 

Nishiwaki, S., 

Ohsumi, S. 

Distribution and Abundance of Large Male Sperm Whales 

in the Antarctic Areas: IIIE, IV, V and VIW (35 E-145 W). 

FP 1 Dawson, S. Acoustic and Ecological Research on Sperm Whales at 

Kaikoura, New Zealand 

FP 2 Bannister, J., 

Harcourt, R., 

Moller, L. 

The Status of Sperm Whales in Australian Waters: 

Developing Methods to Determine their Distribution, 

Population Size/Trend, Habitat and Conservation Status 

FP 3 Mullin, K., 

Engelhaupt, D., 

Cates, C., Barros, 

N. 

Sperm Whale Research in the Gulf of Mexico 

FP 4 Godard, C., Clark, 

R., Kerr, I.,

Teglberg-Madsen,

P., Payne, R. 

Preliminary Report on the Sperm Whale Data Collected 

During the Voyage of the Odyssey 

FP 5 Miyashita, T., 

Kato, H. 

Sightings of sperm whales in the western North Pacific for 

the past twenty years. 

FP 6 Institute of

Cetacean Research 

Sperm whale research by the Institute of

Cetacean Research. 

FP 7 Minerals 

Management

Service 

The Sperm Whale Seismic Study (SWSS) – An Overview

of the Research Administration and Goals 

FP 8 Jaquet, Gendron,

Davis 

Population Characteristics and dive behavior of sperm

whales in the Gulf of California, Mexico (FP) based on an

ongoing project using both new and old techniques 

FP 9 Clark, R., Godard, 

C., Kerr, I.,

Fleming, A.,

Solomon, P., 

Payne, R.

Data Collection Methodologies of Ocean Alliance's Voyage 

of the Odyssey Program
Page 41

 

FP 10 Kato, H., 

Miyashita, T. 

Current status of the North Pacific Sperm Whales and its 

Preliminary Abundance Estimates 

FP 11 Gillespie, D. Mediterranean - Status of field programmes

HI 1 Smith, T., 

Josephson, E., 

Reeves, R., Lund, 

J. 

Linking Historical Whaling Data for Voyages and from

Logbooks for American Open-Boat Sperm Whaling

HI 2 Smith, T., Reeves, 

R. 

Numbers of sperm whales per voyage and barrels of sperm

oil per voyage in 19th century American open-boat 

whaling.

HI 3 Bannister, J. Pre-20th century sperm whaling grounds 

HI 4 Smith, T., Allison, 

C. 

Preliminary Summaries of 20th Century Sperm Whale 

Catches 

HI 5 Smith, T., Reeves, 

R. 

Overview of Research to Date on the Effects of Sperm

Whaling

HI 6 Smith, T., 

Josephson, E 

(Poster) 

Locations of Sperm Whale Catches by American Open-boat 

Whaling

HI 7 Smith, T., 

Josephson, E. 

(Poster) 

Tracks of American Open-boat Whaling From Logbooks 

HI 8 Smith, T., 

Josephson, E. 

(Poster) 

Locations of Sperm Whale Catches by American Open-boat 

Whalers by Vessel Rigging 

HI 9 Warner, N.,

Mesnick, S., 

Straley, J. 

Sperm Whale Depredation on Longlines Worldwide 

HI 10 Straley, J. Using Longline Fishing Vessels as Research Platforms to

Assess the Population Structure and Feeding Ecology of

Sperm Whales in the Gulf of Alaska 

HI 11 Pierce, N., Smith, 

T. 

Procedures for Whaling Logbook Data Entry

HI 12 FI Smith, T., Reeves, 

R. 

Design of a Program of Research on Sperm Whale Catch 

History: Results of a Workshop

HI 13 FI Kasuya, T. Potential For Improvement of 20th Century Sperm Whale 

Catch Data 

HI 14 FI Allison, C., Smith, 

T. 

Progress on the Construction of a Comprehensive Database

of Twentieth Century Whaling Catches 

HI 15 Smith, T., 

Josephson, E. 

(Poster) 

Locations of Sperm Whale Catches in the 20th Century 

HI 16 FI Best, P. Estimating the Landed Catch of Sperm Whales in the 19th

Century

HI 17 FI Best, P. Estimating the Landed Catch of Sperm Whales in the 18th

Century

INT 1 FI Whitehead, H. Estimates of the Current Global Population Size and 

Historical Trajectory for Sperm Whales 

INT 2 FI Smith, T., 

Bannister, J., Best, 

P., Childerhouse, 

S., Gunnlaugsson, 

T., Kasuya, T.,

Reeves, R.

Cachalot (Physeter catodon): The Need to Improve Our 

Understanding of Status of Populations 
Page 42

INT 3 FI Barlow, J. Perspectives on Models of Sperm Whale Population 

Dynamics 

LH 1 Re

v 

Best, P. A Summary Review of Sperm Whale Vital Rates 

LH 2 Kato, H., Kishiro,

T., Bando, T., 

Ohata, K., Tamai, 

K. 

Age and Body Length Structure of a Male Sperm Whale 

School Stranded at Ohura Coast, Kagoshima, Japan in

January 2004

LH 3 Not a paper 

LH 4 FI Whitehead, H., 

Mesnick, S. 

Social Structure and Effects of Differential Removals by

Sex in Sperm Whales: Methodology

PE 1 Re

v 

Best, P. Summary Review of Sperm Whale Feeding 

PE 2 Drouot, V., 

Gannier, A. 

Assessing Sperm Whale Feeding Rate 

PE 3 Tamura, T., 

Kubodera, T., 

Ohizumi, H., 

Konishi, K., Isoda, 

T., Fujise, Y. 

Food habits of sperm whales based on JARPN II (2000-03)

PS&M 1 Mesnick, S., 

Engelhaupt, D., 

Lyrholm, T., 

Taylor, B., 

Escorza-Trevino, 

S. 

Population Structure and the Social Animal: Global Genetic 

Differentiation in Sperm Whales 

PS&M 2 Rendell, L.,

Mesnick, S., 

Burtenshaw, J., 

Whitehead, H., 

Dalebout, M.

Assessing Genetic Differentiation among Vocal Clans of

Sperm Whales 

PS&M 3 FI Whitehead, H., 

Mesnick, S. 

Population Structure and Movements of Sperm Whales:

Methodology

PS&M 4 Not a paper 

PS&M 5 Gordon, J., Jaquet, 

N., Würsig, B.

A comparison of sperm whale photo-id research techniques

using large and small vessels in the Gulf of Mexico
Page 43

ANNEX 4: A BRIEF HISTORY OF THE IWC SCIENTIFIC COMMITTEE’S

ASSESSMENTS OF SPERM WHALES

The IWC Scientific Committee conducted extensive

data analysis and population modeling of sperm whales

from the early 1960s. In November 1963 the Committee held

the first of a series of scientific meetings to review

information on sperm whales worldwide. Then it was noted

that “with the present decline of baleen whale stocks,

increasing attention is being devoted to the capture of

sperm whales in many parts of the world” (IWC 1966, p51).

Several recommendations came from that meeting,

including use of marking and blood typing to identify

population structure and collection of both catch and effort

data for determining population status. This meeting was

followed in 1968 by a more extensive review organized by

the UN Food and Agriculture Organization, where several

key issues were addressed. Substantial declines were

noted in catch per effort rates for several regions and the

implications of the sperm whale’s sexual dimorphism and

polygynous breeding system were of concern: “Because of

the polygynous nature of the sperm whales, the

sustainable yield of males might be much larger than that of

females, for all males surplus to breeding may be exploited

without harm to the stock” (IWC 1969 p43).

Several regional assessments were attempted, and

among other things, it was concluded that the estimated

fishing mortality of sperm whales off the South American

Pacific coast was on the order of 11% per annum, and that

the population was declining. P. Best concluded at the next

Scientific Committee meeting that “the present level of

exploitation of male sperm whales in the south-east

Atlantic, and particularly of mature males, must be viewed

with concern” (IWC 1970, p37)..

The Committee gained momentum on sperm whale

matters, continuing with a major review meeting in 1970

(IWC 1971, p40-50). In 1972 the Committee recommended

“that records of 19th Century Whaling be analyzed to

attempt to reconstruct the original sperm whale stock

status in the North Atlantic” (IWC 1973 p. 37). This

concern gave impetus to the idea of organizing an

international workshop on historical whaling records,

which was held in 1977 (IWC 1983). Smith (1981)

summarized the Committee’s sperm whale assessments

from 1963 to 1977. Subsequently, the Committee conducted

three more special meetings and discussed sperm whales at

several annual meetings. An important subsequent

development was the identification of differential depletion

by sex (IWC 1980). However, with the moratorium on

commercial whaling, the Scientific Committee began to

focus on developing management approaches for baleen

whales that continued to be whaled, precluding any

significant consideration of sperm whales. Commercial

sperm whaling and sperm whale assessments had ended by

the late 1980s.

At its 1998 meeting the Scientific Committee discussed

the possibility of conducting a “comprehensive assessment” of sperm whales (IWC 1999, pp 22-24). Five key

studies that had been developed intersessionally were

discussed, including (1) genetic mark-recapture methods,

(2) sighting survey estimates of abundance, (3) population

models of past abundance, (4) review of historical catch

data, (5) review of sperm whale dynamics and (6) biological

and ecological topics such as life history, social behavior,

ecosystem configurations and current anthropogenic

mortality. The Committee discussed 11 papers on sperm

whales that year, and concluded that “many difficult tasks

... must be completed before a Comprehensive Assessment ...” would be possible. However, it agreed to

consider two of these topics at its 2000 and 2001 meetings.

Despite that promising discussion, little further progress

was made until 2003, when the Committee agreed to begin

planning an assessment of sperm whale populations, and

established a steering group to conduct a research

planning workshop (IWC 2004, p 26).

References Cited

IWC. 1966. Report of the Scientific Committee. Report of

 the International Whaling Commission 16:49-63

IWC. 1969. Report of the IWC-FAO Working Group on

Sperm Whale Stock Assessment. Report of the

International Whaling Commission 19:39-83.

IWC. 1970. Report of the Scientific Committee. Report of

the International Whaling Commission 20:33-129

IWC. 1971. Report of the Scientific Committee. Report of

the International Whaling Commission 21:24-108

IWC. 1973. Report of the Scientific Committee. Report of

the International Whaling Commission 23:28-259

IWC. 1980. Report of the Special Meeting on North Pacific

sperm whale assessments. Report of the International

Whaling Commission (Special Issue) 2:1-10.

IWC. 1983. Report on activities of the International

Workshop on Historical Whaling Records. Report of

the International Whaling Commission (Special Issue)

5:1-13.

IWC. 1999. Report of the Scientific Committee. J. Cetacean

Res. Manage. 1 (Suppl):1-52.

IWC. 2004. Report of the Scientific Committee. J. Cetacean

Res. Manage. 6 (Suppl):1-60.

Smith, T.D. 1981. The adequacy of the scientific basis for

the management of sperm whales. Pp. 333-343 in FAO

Advisory Committee on Marine Resources Research.

Mammals in the seas. FAO Fisheries Series No. 5, Vol

III.
Page 44

ANNEX 5: COMPARISON OF PHOTO-IDENTIFICATION AND BIOPSY SAMPLING

A working group led by Gordon and Clapham reviewed

this subject and prepared a table comparing the two

methods of study for sperm whales (Table A5-1).

Photographs and biopsies can both be used to identify

individual sperm whales as well as provide other useful

data. The two types of samples are complementary and

often a research project will aim to collect both from the

same platform (see, for example, CARP/PS&M/5). To

minimize interference and maximize the amount of data

collected in an encounter, it is useful to consider the pros

and cons of both types of sampling. Photographs and

biopsies differ in various ways, including in the extent to

which they can be collected from a representative sample of

the population and whether collecting them is likely to be

complementary to, or interfere with, other data collection

activities. Multiple factors need to be taken into account

when setting priorities for the collection of one type of

sample over another.

Feeding sperm whales behave very predictably.

Provided it isn’t disturbed, a whale will almost always flukeup after no longer than about 12min at the surface

(Whitehead 2003 reported mean, modal, and median

surface times from nine studies to have been between 7.5-

9.5 minutes). Little variability between individuals has been

experienced in researchers’ ability to collect standard

photographs, provided that the animals are not frightened.

Thus, there is a high and consistent probability of being

able to collect a photograph or biopsy if the boat stays

behind the whale and does not scare it. Coming alongside a

sperm whale to obtain a biopsy before it flukes up will

usually disturb the animal significantly. This makes it

unlikely that a photo-identification image will be obtained

on that surfacing, and disturbance may even affect the

animal’s approachability on subsequent surfacings.

Different individuals and components of the population

seem to differ in their susceptibility to being disturbed in

this way, a factor that introduces heterogeneity in capture

probability for both biopsy and photo-identification.

Biopsies can be collected from the tail when a whale flukes

up. Collecting both samples (photograph and biopsy) at

the same time in this way avoids interference and ensures

that the two samples are unambiguously linked. It is often

the case that samples of sloughed skin can be collected

from the whale’s wake. If such samples can be collected

and unambiguously assigned to an individual, a biopsy

may not be required. Mesnick noted that although

sloughed skin is a reliable source of mtDNA, difficulties

can arise when trying to extract microsatellites from this

source.

In terms of their adequacy for individual identification,

biopsies analyzed using microsatellite techniques have

some advantages. For example, every animal sampled can

be identified, and comparisons with other samples

analyzed in exactly the same way are probably more

accurate than photographic comparisons. However, it is

important to recognize that comparisons between different

laboratories, and even within a single laboratory over time,

as equipment is changed, are not necessarily reliable. This

limits the extent to which different groups of researchers

can collaborate and pool identification material. In addition,

it may be impossible to make comparisons with data that

have already been collected, and some groups will not

collect biopsy material on principle, making collaboration

essentially infeasible.

By contrast, photographic data can be shared readily,

and such sharing is made easier by online databases and

digital imaging. With a species as wide-ranging as the

sperm whale, there are great potential benefits of being able

to collaborate and share identification images with other

teams. Matching errors may become a more serious issue

as photographic collections become larger. Provided that

error rates can be quantified in some way, however, there

may be analytical solutions to this problem. Another

consideration is the incremental cost of analysis for

individual identification as the sample size becomes larger.

The genetic laboratory costs are substantial but constant

with increasing numbers of individuals, while the photoidentification costs are low but increasing due to the

number of comparisons to be made. Obtaining biopsies in

situations where it is necessary to make multiple

identifications over a short period of time, e.g., to establish

the nature of social units as part of a population analysis,

could present ethical, financial, and practical (because

whales become sensitized) difficulties. Potentially, biopsies can be used to identify young animals, which may not

fluke-up (calves) and/or that may be much less well marked.

However, sampling calves is often specifically excluded in

field protocols.

It is the complementary nature of biopsies and

photographs that is most striking, and usually it will be

desirable to collect both. When biopsies are collected at

flukes-up, this can be done with little conflict.

Whitehead (pers. comm.) noted that a large proportion

of the sperm whale genetic samples used and analyzed to

date have come from sloughed skin rather than biopsies. In

his view, collection of sloughed skin has advantages over

biopsy sampling ethically, and in some respects also in

terms of efficiency (his group seems to have been able to

obtain more sloughed skin samples per day at sea with the

whales than other research groups, e.g. the Odyssey, have

been able to obtain biopsies). He acknowledged that

sloughed skin sampling also has disadvantages. For

example, one cannot as easily target sloughed skin

collection from a particular individual or class (e.g., calf,

large male) and the DNA obtained is lower quality, which

limits some molecular genetic analyses.
 Page 45

Table A5-1. Comparison of biopsy and photographic sampling for individual identification. (Note that for 

completeness, this table also should have included a column for sloughed skin.) 

Information Biopsy Photograph 

Reliability of matching Good within one lab. All animals can

be identified.

Dependent on image quality and 

degree of marking. Not all animals 

are adequately marked. 

Ease of matching Greater potential for automation. Automation is being developed.

Sex determination Yes Partial (body size, callus, calves)

Hormone analysis Yes (blubber sample) No 

Contaminant analysis Yes (blubber sample) No 

Length No Yes (although depends on image 

content and quality) 

Stable isotopes Yes No 

 

Practical considerations 

Cost High Lower 

Ability to share data Poor Good 

Potential for capture heterogeneity High (?) Low (?) 

 

Compatibility with other data 

collection

 

Representative behavior No Yes 

Defecation rate Incompatible Compatible 

Acoustically derived length Incompatible Compatible 

Short-term repeated identifications 

for movement, social organization, 

etc.

Difficult Compatible 

Proportion of calves Incompatible Compatible 

Coda collection Incompatible Compatible