(from "Chairman's Report of the Fifty-Second Annual Meeting")
11.1.1.2 ABUNDANCE ESTIMATION
An intersessional Working Group was established in 1998 to
review proposed methods that estimate abundance from
multi-year data and to evaluate abundance estimators that
might be used to produce estimates used in the RMP when
heterogeneities occur and assumptions are violated. No new
methods to estimate abundance from multi-year data were
presented to the intersessional Working Group to review,
and the Scientific Committee agreed that the most
appropriate analytical method to be used in the future
depends on the desired performance, information collected
and ease of implementation.
The Scientific Committee agreed that the outstanding technical and RMP implementation issues had been resolved and recommended that annotations to the RMP should now be drafted to reflect this. An intersessional Working Group was established to continue work on matters relating to abundance estimation under the RMP, and there will be a report on progress at next year's meeting.
11.1.1.3 NORTH PACIFIC MINKE WHALE TRIALS
FINAL IMPLEMENTATION TRIALS
Last year, the Scientific Committee recommended that the
Secretariat conduct a set of Implementation Simulation
Trials for North Pacific minke whales. The Committee noted
that not all the trials had been run intersessionally because it
was evident from discussions during the JARPN review that
re-specification of the trials was highly likely.
The procedure used to condition the trials in the past would not necessarily constitute an adequate basis for a re-assessment of the 'J' stock when this is conducted because of uncertainties surrounding the Korean CPUE (catch per unit effort) data and the limited coverage of the survey data. The Committee agreed that a future reassessment of this stock would need to be based on a comprehensive review of the available information and that future trial results should distinguish between commercial and incidental catches when listing catches for the 'J' and 'O' stocks.
INCIDENTAL CATCHES
The Scientific Committee welcomed new information about
incidental catches off Korea in 1999. It noted that almost half
of the animals had been sampled and encouraged continued
sampling of bycatch and strandings. It was observed that the
stranded animals were in too poor a condition for the cause
of death to be determined, so some of these animals may
have died as a result of a fishery interaction. The Scientific
Committee agreed to update the specifications for the trials
to include the information on the size of the Korean bycatch
(56 animals), including its seasonality and sex-structure. It
also agreed not to modify the approach agreed last year to
include incidental catches off Korea in the trials, and to use
56 as the incidental catch for 1999.
The Scientific Committee noted that the reported bycatch off Japan for 1999 was 19 and agreed to update the information on bycatch used in the appropriate trials to reflect this new information. It also agreed to continue to use a range of annual incidental take of minke whales by Japan of 25-75 in future Implementation Simulation Trials, even though use of these options for trial purposes did not constitute agreement by all Committee members that the entire range was plausible or indeed that this was the entire plausible range.
MIXING AND STOCK STRUCTURE
The Scientific Committee agreed to consider three
stock-structure hypotheses in the Pacific based on the results
presented in the JARPN review and new information
received:
The Scientific Committee also agreed that for trial purposes, sub-areas 7 and 8 would be combined, but that 'J' stock animals will be assumed to be found in sub-area 7 only. The population structure for the 'O' stock in these sub-areas would be assumed to be the same, and sub-areas 7 and 8 would be combined into a single Small Area when applying the RMP in the context of Implementation Simulation Trials.
RE-SPECIFICATION OF FINAL TRIALS
The Scientific Committee agreed revised specifications for
the North Pacific minke whales Implementation Simulation
Trials and recommended that the Secretariat conduct the
trials during the intersessional period and report the results to
next year's meeting.
SIGHTINGS SURVEYS
The Scientific Committee received a report on a joint
Japanese and Russian sightings survey conducted in 1999 in
the Okhotsk Sea. It agreed that the conduct of the survey was
appropriate for use in the RMP and noted with appreciation
that the survey was carried out jointly with the Russian
Federation.
The Scientific Committee was pleased to receive a research plan for a further joint Japanese and Russian sightings survey in the Okhotsk Sea from July to September 2000. It recommended that the Commission request the relevant authorities of the Russian Federation to grant permission in a timely fashion for Japanese vessels to survey in its EEZ, including both the southern and the northern portions of the entire Sea of Okhotsk and associated gulfs and bays because of the apparent higher density in the immediate near shore areas.
Reports were also received of a joint Korea-Japan minke whale pilot sighting survey conducted in 1999, another survey carried out in May 2000 in the eastern waters of Korea, plans for a similar survey in the same area in September 2000 and plans for two further surveys in the western waters of Korea (in the Yellow Sea) in April and September 2001 for which there would be Committee oversight. The Scientific Committee also suggested that the collection of biopsy samples would provide additional valuable information for the Implementation Simulation Trials.
11.1.1.3 NORTH PACIFIC BRYDE'S WHALES TRIALS
The Scientific Committee reported that the RMP
Implementation Simulation Trials were given low priority
last year and that no progress had been made. It is quite likely
that no substantial progress will be made in the coming year
either, since high priority is again being given to completing
the North Pacific minke whale trials.
A detailed analysis to address a question raised last year about the validity of species identification of Bryde's and sei whales in commercial catches in Japanese pelagic whaling in 1973 and 1974 was presented to the Scientific Committee. The analyses of individual allozyme and operational information implied that the species identification was correct. The Scientific Committee welcomed this thorough analysis, and agreed that it resolved the uncertainties raised last year.
The Scientific Committee reviewed the report of a sightings survey performed in August-September 1999, as part of a multi-year survey schedule and agreed that the resulting abundance estimates could be used in the RMP. The Committee welcomed the information on successful biopsy sampling from the survey and agreed that for future surveys, it would be useful to include information on sighting angles and distances and on the experiments conducted in the cruise reports.
The Scientific Committee also received a description of the next sightings survey in this series that will be conducted using one vessel instead of two, extending the planned completion time of the series from four years to five. The survey will be conducted in August and September 2000 in the band from 137°30'-145°E, again from 10°-43°N. The Committee noted that the design of the northern portion of the survey was not ideal, and recommended that this portion be restructured to work on and off shore to the extent possible. Scientific Committee oversight of the survey was requested. Finally, the Scientific Committee recommended that the Commission request the relevant authorities of the Federated States of Micronesia, the Commonwealth of the Northern Mariana Islands and the USA to grant permission in a timely fashion for Japanese vessels to survey in their respective EEZ waters.
11.1.1.4 NORTH ATLANTIC MINKE WHALES
In the Commission, the Chair of the Scientific Committee
drew Commissioners attention to ongoing work on North
Atlantic minke whales - an item not on the agenda of
IWC/52. The Committee had received reports on the 1999
Norwegian sightings survey for minke whales, the fourth in
a six-year programme to cover the north-eastern Atlantic to
obtain abundance estimates to be used for calculating catch
limits by the RMP at the end of the survey period. The
Committee agreed that the surveys should continue to be
conducted in a manner suitable for use in the RMP and
recommended that the Commission request the relevant
authorities of the Russian Federation to grant permission in
a timely fashion for Norwegian research vessels to survey in
its EEZ waters. The Chair particularly drew attention to the
proposal that an RMP implementation review for North
Atlantic minke whales be conducted in 2002, when a new
estimate of abundance from Norway's series of annual
surveys and analyses of samples collected over the last five
years would be available. The Scientific Committee believed
that the review was important since Norway is harvesting
whales using the RMP under objection and would therefore
be due for an implementation review if the RMS were in
effect.
11.1.2 Commission discussions
NORTH PACIFIC MINKE WHALES
In the Commission, Japan commented that the
comprehensive evaluation of this stock had already been
completed, and that once the parameter setting for the RMP
and Implementation Simulation Trials are completed, it
would be possible to start sustainable use of this stock. Japan
attributed the delay in completion of parameter setting and
implementation of the RMP by the Scientific Committee to
the attitudes of some anti-whaling scientists, e.g. the putative
hypothesis that a number of independent minke whale
groups exist in the North Pacific (a hypothesis that Japanese
research begun in 1994 in the northwestern Pacific has
virtually ruled out) and claims of high incidental catches,
based on DNA analysis of whale meat sold on the Japanese
market - a technique considered by Japan to be not reliable.
It added however, that it intended to further strengthen and
enhance its scientific activities with the aim of an early
implementation of the RMP in future.
New Zealand regretted the characterisation of Scientific Committee members by Japan as being pro- or anti-whaling. It expressed the hope that the Commission would be guided by the quality of the scientific data presented by those scientists rather than the perceived anti- or pro-whaling stance of the country in which they happen to live. New Zealand added that the Scientific Committee had accepted the possible stock-structure hypotheses considered in its report as plausible. It noted that the use of molecular genetics is a fundamental tool in developing and implementing the Revised Management Scheme (RMS), whether through non-lethal research in the field or through tissue samples from animals killed in whaling operations or from bycatches.
In response to New Zealand's reference to bycatches, the Chair of the Scientific Committee confirmed the importance of developing ways to estimate bycatch levels to meet the Commission's goal of ensuring that the total catches over time assumed by the RMP are not exceeded. She added that a Working Group will meet at next year's Scientific Committee meeting to address the estimation of incidental catch and other human-induced mortality of baleen whales, particularly for stocks of current interest in the development of Implementation Simulation Trials. This will include the most appropriate methods to ensure that any market sampling and analyses are carried out in such a way that unbiased bycatch estimates are obtained, with reasonable estimates of their precision.
In response to a question, the Chair of the Scientific Committee commended Japan and the Republic of Korea for supplying information on bycatches in their progress reports to the Scientific Committee and reminded all delegations of their responsibility under Resolution 1997-4 to report all whales taken incidentally in all fishing operations.
The Republic of Korea welcomed the new abundance estimate for minke whales in the East Sea/Yellow Sea/East China Sea stock (using Korean CPUE data) and added that future surveys should determine the true abundance in the area and contribute to assessment and management. The Republic of Korea again drew the Commission's attention to the use of the name 'Sea of Japan' and indicated that it would like simultaneous use of the name with 'East Sea'. It reported that, as advised at many international meetings, it had tried to negotiate bilaterally with Japan, but with no success. Japan responded that the IWC is not a suitable place for discussing geographic names. The Chairman indicated that the Commission would note the views expressed.
NORTH PACIFIC BRYDE'S WHALES
Japan expressed regret that no progress has been made since
last year, and strongly urged that progress should be made in
future.
NORTH ATLANTIC MINKE WHALES
Norway confirmed that it puts great emphasis on extending
its sightings surveys as an essential part of the whole scheme
of collecting information necessary for its management of
the Northeast Atlantic minke whale.
11.1.3 Action arising
The Commission accepted the recommendations and work
plan of the Scientific Committee.
11.2 Whale stocks
11.2.1 Report of the Scientific Committee
11.2.1.1 SOUTHERN HEMISPHERE MINKE WHALES
IN-DEPTH ASSESSMENT OF SOUTHERN HEMISPHERE MINKE WHALES IN
2001
The Committee agreed that the following topics should be
covered in an in-depth assessment and that planning should
begin, noting that it will take more than one year to
complete.
The changes to DESS (IWC Database and Estimation Software System) requested last year have been made and will enable item (1) above to be completed. The changes included updating definitions of species codes. The Committee also recommended that JARPA data be analysed to determine the proportion of dwarf minke whales, both in the minke whale catch data and in sightings covered by JARPA. The Committee also agreed, pending the review, on a way to deal with the first five IWC/IDCR surveys which used a different design from subsequent surveys and on an option for including RMP Small Area abundance estimation.
The Scientific Committee identified a number of factors that must be taken into account when analysing the data from the IWC SOWER and IDCR cruises, including consistency in use of 'undetermined' species codes, accounting for changes in ice-edge when comparing surveys, the possibility of consistent differences between the detection function shapes in closing and IO (independent observer) mode and general issues of trends in estimated detection functions.
With respect to inter alia estimating relative or absolute minke whale abundance from JARPA surveys, the Committee reviewed some simulation work and recommended that spatial modelling methods that are able to estimate the degree of clustering reliably without strong assumptions about its nature or degree should be investigated. These have the prospect of providing objective estimates of the degree of clustering on real surveys, of being able to accommodate clustering which varies in degree within a single survey and of providing unbiased GAM-based estimators.
The Scientific Committee welcomed reports of sightings surveys on the former whaling grounds off northeastern Brazil. The Committee recommended that the surveys be expanded to include the entire breeding ground and that consideration be given to estimation of g(0). There are plans to expand the surveys to include photo-identification and biopsy work in the future, and the Committee looked forward to seeing results of this further work in due course.
Results relating to minke whales from the 1999/2000 JARPA survey in Area IV and the eastern part of Area III were also presented. Minke whales were the most frequently sighted species. No dwarf-form minke whales were sighted. It was reported that the sighting rate on this survey was higher than that on any previous JARPA survey in Area IV.
An analysis of mtDNA in the ordinary form minke whales from Antarctic Areas V and VIW, using samples from the 1988/89-1998/99 JARPA surveys found some preliminary evidence of genetic differentiation of group VW, from both the 'western stock' and from the rest of the groups examined in Areas V and VIW. This requires further investigation.
Information on 78 whale tags recovered on the factory ship Sovietskaya Ukraina from 1972 until 1986 was presented. In the case of minke whales, all but one of the Discovery marks had previously been reported to the IWC Secretariat, but none of the Soviet tags had.
FINALISING PLANS FOR THE IN-DEPTH ASSESSMENT
The Scientific Committee agreed that high priority be given
to the validation and incorporation of existing IWC/SOWER
survey data into DESS, including the 2000/01 survey data.
The Committee recognised the value of previous analyses
and noted that it was important to have as long a series of
estimates as possible to address the issue of trend most
effectively.
While the estimates of Southern Hemisphere minke population sizes accepted in the Comprehensive Assessment2, (totalling 760,000, obtained using IWC/IDCR data from 1982/83 to 1989/90) were the best available at the time for the years surveyed, they are no longer appropriate estimates of current minke whale abundance. Some initial crude extrapolations of the incomplete third circumpolar set of surveys led to a point estimate that was appreciably lower than the total of the previously agreed point estimates by Area from the Comprehensive Assessment2. However, there are a number of factors that make interpretation difficult, including:
In addition, without calculation of confidence limits for the crude point estimate, it was not possible to conclude whether the appreciable difference noted above was statistically significant. Although there are plans to address these difficulties, the Committee is currently unable to provide reliable estimates of current minke whale abundance.
The Scientific Committee agreed that there was an urgent need to address trend-related issues, and to provide up-to-date estimates of minke whale abundance. To this end, the Committee agreed that it is very important to complete the third circumpolar set of surveys, and recommended participation in the 2000/01 Antarctic minke whale survey.
While the value of the analyses of IWC/IDCR-SOWER data conducted to date was recognised, an integrated approach to the future analysis of IWC/IDCR-SOWER data was proposed.
The Committee considered it important that results that will facilitate the review of Southern Hemisphere minke whale abundance be presented at its next meeting and recommended that the tasks listed below be assigned high priority.
The Committee agreed that it was important to make substantial progress on items (a) to (c) by its next meeting, and a subgroup was established to develop plans for the intersessional workshop.
2 IWC, 1991, p.117 table 1, with a minor correction in IWC, 1993, p.114, table 1
11.2.1.2 SOUTHERN HEMISPHERIC HUMPBACK WHALES
REPORT OF THE INTERSESSIONAL WORKING GROUP
The Scientific Committee reviewed intersessional work to
prepare for a preliminary assessment of Southern
Hemisphere humpback whales. This included an
examination of the results of modelling work that used
information and assumptions with respect to stock identity,
current abundance, rates of increase for putative stocks and
data on historic catch sizes and locations.
The Scientific Committee agreed that this represented a useful first step at a preliminary assessment of Southern Hemisphere humpback whales. In particular, it had focused attention on what information and additional work was necessary for a fuller assessment (see below).
UPDATE OF ANTARCTIC CATALOGUE:
The Committee welcomed the information presented on the
progress of the IWC Antarctic Humpback Whale Catalogue
and recommended continued funding for this work.
ESTIMATES OF ABUNDANCE AND RATE OF INCREASE
The Committee reviewed estimates of population size and
increase rates for humpback whales in Area IV, using data
collected on JARPA surveys (between 1989/90 and
1999/2000) and made suggestions for further intersessional
work. Similarly, the Committee reviewed DESS-based
abundance estimates of nine cetacean species (including
humpback whales) from IDCR-SOWER cruises. A total of
83 sightings of 178 humpback whales were made on the
1999/2000 SOWER circumpolar survey. Biopsies were
obtained from 37 animals. The Committee expressed its
gratitude to the Japanese government for providing the two
vessels used in the research.
STOCK STRUCTURE
The Committee reviewed a number of studies relating to
stock structure (e.g. using genetic analysis, photo-id
comparisons, artificial 'Discovery' marks, catch data). The
preliminary results are generally compatible with the
breeding/feeding stocks scenario considered by the
Committee and they agreed to a number of additional stock
scenarios that should be considered in any future modelling
exercises.
DATA AND ANALYSES NEEDED TO REFINE THE ASSESSMENT
The Committee recommended that further modelling and
assessment work be undertaken that took into account its
discussions at this meeting concerning the following
factors:
11.2.1.3 WESTERN NORTH ATLANTIC RIGHT WHALES
REVIEW OF STATUS AND TRENDS
A workshop was held at Woods Hole, USA in October 1999
in view of the Scientific Committee's serious concerns over
the status of the stock, and last year's strong
recommendation that the Comprehensive Assessment of this
stock should remain of high priority. The workshop
reviewed the available data, available population models,
status and trends. The latter included discussion of factors
affecting trends and a comparison with other populations,
particularly those in the Southern Hemisphere that, in
contrast with those in the North Atlantic, are showing higher
reproductive rates and population increase.
The Scientific Committee also received the report of a Workshop on the Causes of Reproductive Failure in North Atlantic Right Whales and New Avenues of Research, held at Falmouth Massachusetts in April 2000 under the auspices of the US National Marine Fisheries Service. The Workshop had been prompted by evidence that reproductive dysfunction may be a contributory factor in the population's failure to recover. Its goal was to identify factors potentially affecting reproduction and to develop an appropriate and feasible research strategy to investigate them.
LONG-TERM EFFECTS OF TAG IMPLANTATION
The Committee reviewed the report of a Workshop on the
Effects of Tagging on North Atlantic Right Whales. Some of
the 55 individuals tagged between 1988 and 1997 had
developed swelling at the implantation site. However, the
report was inconclusive as no information had been provided
to definitively evaluate the effects of tagging on right
whales. The Scientific Committee recognised that time scale
information on the effects of tagging would be useful,
notably the timing and type of tissue response at the site of
implantation; it recommended that such an analysis be
conducted.
In discussion of a request for a more precautionary approach to tagging this highly endangered species, the Committee recommended that a further analysis of the risks of using implantable tags with this species be undertaken, paying particular attention to possible differences in reproductive success in tagged versus non-tagged females. It recommended that implantable tags proposed for use on the North Atlantic right whale be first tested on harvested bowhead whales. Appropriate tests could include assessing the depth and nature of the wound, the extent to which epidermal material is carried into the wound and the holding strength of attachment devices.
RECOMMENDATIONS FOR FURTHER ACTION
The Scientific Committee endorsed all the recommendations
from the Workshop on Status and Trends and from the
Workshop on Causes of Reproductive Failure. In discussing
the recommendations from the Workshop on Status and
Trends, the Committee noted that the Workshop had agreed
that at least two aspects should be separated out when future
research strategy is decided:
The Scientific Committee confirmed that whilst both are important, and recommendations for both have been developed, the highest priority must be accorded to category (2). Despite the improvements that can and should be made in terms of refining the modelling of this population, it is clear that none of those refinements will lead to a change in the conclusion that:
by any management criteria applied by the IWC in terms of either commercial whaling or aboriginal subsistence whaling, there should be no direct anthropogenic removals from this stock.
The evidence that this population (possibly the only potentially viable population of this species) is in serious danger is compelling, and the need for further research under category (1) above should not be seen as a reason for delaying immediate and highest priority action under (2). In short, the population:
In addition, there is some evidence (e.g. from skin lesions) that the overall health of the population has decreased since the 1980s.
Research recommendations arising from the Status and
Trends Workshop
The Scientific Committee recommended that highest priority
be assigned to research into means of reducing mortality
from entanglements and vessel collisions. It further
recommended that an international multidisciplinary
workshop be held to review progress and to identify
priorities for further work and the most promising
approaches to management action to reduce mortality. The
Scientific Committee felt that it is essential that every effort
be made to ensure that requisite data are available. At a
minimum this must include good temporal and geographical
information on vessel traffic, fishing gear effort and
distribution for the entire east coast of North America. The
Committee recommended that the Commission urge the
relevant governments to ensure that such data are recorded,
collated and made available. In this context, the Committee
recommended that a Geographic Information System (GIS)
project be conducted to overlay effort data on to information
on right whale distribution together with that of fishing gear,
shipping activity and other threats.
Notwithstanding that research into reduction of mortality should be given highest priority, the Scientific Committee considered the proposed Genetics Workshop to be especially important. It also recognised that reduced calving success may reflect the impact of a variety of human activities that alter coastal habitats. It recommended that research on these and other habitat quality issues be intensified and that the proposed multidisciplinary workshop evaluate the impact and mitigation of habitat stressors.
Management recommendations arising from the Status
and Trends Workshop
The Scientific Committee reiterated that it is a matter of
absolute urgency that every effort be made to reduce
anthropogenic mortality in the population to zero, and
recommended that the Secretary write to the International
Maritime Organisation (IMO) to underscore the severity of
the current status of North Atlantic right whales, and to
request their assistance with implementing measures within
the international maritime community for the conservation
of this critically endangered population. The Committee
further recommended that the data on number of ships
entering the area and the speeds at which they are travelling
be investigated, and that whale distribution be overlaid with
traffic distribution and shipping lanes to assess the need and
feasibility of further regulatory actions related to ship
routing and reduction of ship speed.
In addition to the above, the Committee recommended that, for the immediate future, and given the important management implications of the estimate of survival rate, annual updates of survival rate estimates be presented to, and considered by, the Committee. That would have the further benefit of taking advantage of data now available from a major offshore area poorly sampled during the early 1990s. It also recommended that it would be useful to include other right whale populations in a comparative analysis of genetic diversity and reproductive rates.
And finally, the Committee drew the Commission's attention to concerns expressed at the Woods Hole workshop over transfer of biological samples under CITES regulations. Transfer of samples is still very difficult in certain cases, and can constitute a major impediment to research on critically endangered species such as northern right whales. It reiterated its earlier recommendation that the Commission should strongly urge member nations to facilitate the transfer of such samples, and that the IWC Secretariat approach the CITES Secretariat to consider ways of expediting permits for bona fide institutions conducting conservation-related research on endangered species.
Recommendations arising from the Workshop on the
causes of reproductive failure
The Committee agreed that if every effort is going to be
made to improve the status of the North Atlantic right whale,
it is important that the reasons for the reproductive
dysfunction be established as soon as possible and strongly
recommended that a programme of research identified at the
workshop be supported to the fullest extent possible. The
Committee agreed that none of the five possible factors the
workshop considered could be discounted as a possible
cause of the reproductive dysfunction observed in the North
Atlantic right whale. In fact, it is likely that no one factor is
entirely responsible, and two or more factors could be
interacting, possibly over different time scales. It is therefore
important that the proposed research programme considers
all possible factors and is interactive and multidisciplinary in
nature. For such a programme to be successful, there needs
to be strong central coordination. The Committee therefore
endorsed the recommendation that a steering committee be
established to develop protocols, review results and
progress, and recommend revisions to the research
programme recommended in the workshop report.
The Committee also recommended:
The Committee agreed that the Secretary should be asked to write to the US National Marine Fisheries Service (NMFS) and the Canadian Department of Fisheries and Oceans, informing them of the Committee's serious concerns over the status of this stock, and seeking their support for implementation of the various actions recommended.
At their meeting in 2001, the Scientific Committee will review progress on the recommendations outlined above and on the outcome of the Genetics Workshop.
11.2.1.4 SOUTHERN HEMISPHERE BLUE WHALES
DIFFERENTIATION OF SUBSPECIES
The Scientific Committee reiterated the importance of
resolving the issue of the proportion of pygmy blue whales
south of 60°S in relation to interpretation and possible
correction of abundance estimates for 'true' blue whales in
this region. It noted that it was still not possible to genetically
distinguish 'true' blue (Balaenoptera musculus intermedia)
and pygmy blue whales (Balaenoptera musculus
brevicauda), but that work was ongoing. The Committee
renewed its request that additional material, especially from
known 'true' blue whales, should continue to be sought for
genetic analysis to assist in the resolution of this issue.
With respect to acoustic work, the Scientific Committee agreed that, ideally, dedicated cruises should be undertaken to areas of known concentration of 'true' blue whales although opportunities should also be taken to take advantage of 'piggy backing' on other operations. While more rapid progress with the acoustic work is desirable, that would depend on more frequent contacts with blue whales. As the population is still small and scattered around the Antarctic, the probability of encounters is low - only one blue whale was recorded on the 1999/2000 IWC/SOWER cruise. The current survey design, which allocated a sizeable proportion (25%) of the IWC/SOWER cruise to blue whale research, and which allowed this to be flexible in nature to take advantage of blue whale encounters, was probably the best that could be achieved at present, until areas of consistent blue whale abundance are discovered. The Committee reviewed proposals for analysis of existing recordings from SOWER and IWC research cruises and agreed that this work should be undertaken.
The Committee reviewed information on future areas for blue whale studies. These included coastal waters of southern Chile and the Chilean fjord system, an area off Namibia where 'true' blue whales were once caught during the winter (breeding) season and an area now being studied off southeastern Australia where blue whales (subspecies uncertain) have been seen in summer and autumn. The Committee agreed that when considering possible blue whale wintering areas in the southwestern Pacific, it may be useful to identify areas of warm water euphausiid concentrations.
Two studies had attempted to determine from historic catch data the proportion of pygmy blue whales likely to be present in waters south of 60°S. Both agreed that a small number of pygmy blue whales were found in those waters, but in low numbers compared to 'true' blue whales. It was concluded that if pygmy blue whales were present they were unlikely to constitute more than 5% of the catch. The Committee also recommended satellite tagging of biopsied pygmy blue whales of known length prior to their migration to provide information on their possible occurrence south of 60°S.
ABUNDANCE ESTIMATES
The Scientific Committee reviewed blue whale abundance
estimates from the three IWC/IDCR/SOWER circumpolar
cruises and agreed that an abundance estimate, not
designated by subspecies, south of 60°S over the last two
decades of the 20th Century was in the range of 400
(CV=0.4) to 1,100 (CV=0.4). The estimate will be an
underestimate because the areas south of 60°S were
incompletely surveyed.
The Committee also agreed that inferences about trends and their statistical significance could not currently be made using the above estimates for a number of reasons:
FURTHER WORK
At its next meeting in 2001, the Scientific Committee plans
to (a) review progress in subspecies differentiation,
including acoustic analysis, and (b) prepare for stock
assessment of Southern Hemisphere blue whales, including
pygmy blues.
11.2.1.5 OTHER SMALL STOCKS
BOWHEAD WHALES
The Scientific Committee's deliberations on the Baffin
Bay/Davis Strait and Hudson Bay/Foxe Basin stocks of
bowhead whales are discussed under Item 10.3.1 of this
report.
Norwegian whalers had seen several bowheads on the west coast of Spitzbergen (at ca 80°N) in late May-early June 2000. Some had also been seen there two years ago. In recent years there have been sightings in pack-ice east of Spitzbergen, among and south of the Franz Josef Islands and along the west coast of Novaya Zemlya in the eastern Barents Sea. Additional sightings have been reported by Russian aerial surveys in other Arctic regions. The population identity of all these whales is currently unknown.
Work on the Okhotsk Sea bowhead population will continue in summer 2000. A recent publication gives details of North Pacific pelagic Soviet whaling, including 133 animals taken in 1968 in the Shantar area of the Okhotsk Sea, where the present field work is located.
WESTERN NORTH PACIFIC GRAY WHALES
In the fourth field season of joint Russian-American research
on the gray whale summer feeding ground off north-eastern
Sakhalin Island, 88 individuals had been photo-identified
and 42 animals biopsied. Genetic analysis so far showed no
fixed or diagnostic mtDNA differences between that
population and eastern gray whales, although there were
statistically significant differences between the two
populations in terms of haplotype frequencies. Last year for
the first time apparently thin whales had been seen (as
elsewhere in the North Pacific), although there were no data
on food limitation off Sakhalin Island. Field work will
continue in summer 2000; it is anticipated that few new
individuals will be identified, indicating that the total
population size is perhaps about a hundred whales.
The Scientific Committee received a report of a molecular analysis of a gray whale sample from a market in Japan which showed that it had a mtDNA haplotype identical to a haplotype from the eastern North Pacific population. The high number of haplotypes shared between the western and eastern gray whale populations was noted. There was a view that the whale concerned was a western animal and that the market sample's identity could be resolved by genotype comparison with tissue from the gray whale killed off Hokkaido in 1996.
OTHER STOCKS
A number of papers were presented to the Scientific
Committee that gave details on other small stocks. These
included: North Atlantic blue whales; minke whale
movements in relation to ice conditions off the Chukotka
Peninsula; right whales in the southeastern Bering Sea;
North Pacific humpbacks; southern right whales; and
abundance estimates of fin, sei and sperm whales south of
60°S.
11.2.2 Commission discussions and action arising
SOUTHERN HEMISPHERE MINKE WHALES
Japan stated that research on the abundance of Southern
Hemisphere minke whales is the issue in which they have the
strongest interest. It noted that in addition to its scientific
permit research to elucidate the stock structure and
biological parameters, it has provided vessels, equipment
and human resources equivalent to US$1,500,000 per year
since 1978/79 under the IDCR and/or SOWER circumpolar
sighting surveys. It has provided all data to the Scientific
Committee. It believes that the IWC is the appropriate
international organisation for large cetacean management
and would like to continue to contribute in this way
providing that IWC carries out its activities in accordance
with the Convention. It added that although previous
abundance assessments of Southern Hemisphere minke
whales have already demonstrated that this stock is healthy
and robust, it believed that the Scientific Committee's
proposed review is generally appropriate and was willing to
provide a research vessel to provide data for this review.
However, it strongly requested that the review be carried out
in a thorough and cautious manner.
Australia also considered the Southern Hemisphere minke whale abundance estimate to be very important, recalling that this is the stock harvested by Japan in the Southern Ocean Sanctuary under Special Permit. It was very concerned to hear that the stock size may now be appreciably lower than estimated in 1990, particularly in view of evidence presented in the Scientific Committee that there is more than one minke whale species present. Australia therefore agreed strongly with the Committee's recommendation to investigate trends and provide a revised abundance estimate for this region. The USA, New Zealand, the UK, France and a number of other delegations expressed similar views. New Zealand stressed the need for future abundance assessments to be done on a per stock, rather than on a per species basis. Sweden and Switzerland supported the need for better data. Italy and Germany stressed the need for a precautionary approach to management of minke whales in the Southern Hemisphere.
In responding to the possibility that there are two types of minke whale in the Antarctic, Japan believed that the 1990 minke whale assessment of 760,000 did not include dwarf minke whales as this species was distributed in a different area to the ordinary minke whale. It also commented that perhaps the Southern Hemisphere minke whale population had overshot its carrying capacity, and referred to data from a 1979 paper of Dr Oshumi that at the beginning of the 1900s, the population numbered about 85,000. Japan noted the remarkable increase in numbers since then and wondered whether the uncertainty with the 1990 estimate of 760,000 was really a problem.
St Lucia expressed concern in the way the information from the Scientific Committee was being treated in the Commission. It considered that some governments treated the Committee's guidance selectively in that they would accept guidance when it could be used to support an anti-whaling approach, but would call for more advice when provided with information that could support whaling. St Lucia considered that the Commission should be more consistent. Dominica supported this view.
In response to a question from Monaco on what the revised stock size estimate might now be, the Committee Chair reported that the Committee had only considered a crude preliminary point estimate and had identified a number of potential problems with that. She added that better information could be provided once the third circumpolar survey and further data analyses identified in the report had been completed. Norway supported the Scientific Committee Chair's response and emphasised that there was no reason for any immediate action or concern related to the current scientific take by Japan even if there is a decline in numbers and even if there are sub-stocks and sub-divisions of minke whales in the area. The People's Republic of China stated that until a revised estimate was available, its position would be taken on the basis of the 1990 estimate.
SOUTHERN HEMISPHERE HUMPBACK WHALES
Japan commented that it was happy with the progress made
on the Comprehensive Assessment of this stock. It referred
to analysis of the JARPA survey data for Areas IV and V
since 1987/88 that suggest a stock size in Area IV of 12,000
and high rates of increase of 13.4%. Japan has also provided
earplugs so that the ages of whales taken can be evaluated.
Japan wishes to contribute further to the Comprehensive
Assessment through continuing JARPA surveys and the
provision of vessels for the SOWER circumpolar cruises.
The Chair of the Scientific Committee thanked Japan for these contributions. She noted that the earplug calibration study would help determine the age of sexual maturity, and thereby assist in determining whether or not the high estimated rates of increase are plausible.
WESTERN NORTH ATLANTIC RIGHT WHALES
The UK thanked the Scientific Committee for its work on
Western North Atlantic right whales and added that it is clear
that there is a serious and worrying situation with respect to
this stock and that every effort needs to be made to reduce
anthropogenic mortality in the population to zero. It
acknowledged the far-reaching and sound recommendations
from the Scientific Committee and expressed the hope that
they could be endorsed.
Discussion of a Resolution relevant to this population is considered under Item 17.4 of this report.
SOUTHERN HEMISPHERE BLUE WHALES
Japan thanked the Chair of the Scientific Committee for her
detailed report. Japan was one of the major sponsors of the
original proposal for the blue whale research programme and
it planned to continue its support. However, it also called on
those nations who had been involved in whaling of blue
whales in the past to support this survey via financial and
other concrete contributions.
OTHER SMALL STOCKS
The USA expressed concern about the status of the small
populations of bowhead whales in eastern Canadian waters.
While the USA appreciated the work of Canadian scientists
on the status and abundance of this stock, it was pleased that
the Scientific Committee did not accept the estimate of 345
proposed in a Canadian document. The USA indicated that
they looked forward to future results from further studies.
The Resolution on these stocks was dealt with under Item 10.3 of this report.
Regarding the report of the presence of gray whale meat on the Japanese market, Japan commented that this was not confirmed by its own survey. Japan acknowledged that the condition of the western North Pacific gray whale stock is declining due to deteriorations in the stock's environment, and added that it is making efforts to protect this stock by applying rigorous enforcement measures.
There were no comments on other small stocks.
SCIENTIFIC COMMITTEE RECOMMENDATIONS
The Commission noted the report of the Scientific
Committee and accepted its recommendations.
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