5. WHALE STOCKS

(from "Chair's Report of the 58th Annual Meeting")

5.1 Antarctic minke whales

5.1.1 Report of the Scientific Committee
The Committee has carried out annual surveys in the Antarctic (south of 60°S) since the late 1970s. The last agreed estimates for each of the six management Areas for minke whales were for the period 1982/83 to 1989/90. At the 2000 meeting, the Committee agreed that whilst these represented the best estimates for the years surveyed, they were no longer appropriate as estimates of current abundance. An initial analysis of available recent data had suggested that current estimates might be appreciably lower than the previous estimates.

Subsequently, considerable time has been spent considering Antarctic minke whales with a view to obtaining final estimates of abundance for the three circumpolar cruises5 and considering any trend in these. This has included a review of data collection methods and analytical methodology. After considering many of the factors affecting abundance estimates, there is still evidence of a decline in the abundance estimates, although it is not clear how this reflects any actual change in minke abundance. Three hypotheses that might explain these results have been identified:

(1)
a real change in minke abundance;
(2)
changes in the proportion of the population present in the survey region at the time of the survey;
(3)
changes in the survey process over time that compromise the comparability of estimates across years.
A considerable amount of work has been undertaken and further work is ongoing. The final part of the Third Circumpolar Survey undertaken as part of the IWC's SOWER research programme has been completed and preliminary work suggests that the estimated abundance may be down to about 40% of the estimates from the Second Circumpolar Survey. Experimental work to examine possible causes was undertaken on the 2004/05 and 2005/06 cruises and further work will be undertaken on the 2006/07 cruise.

With respect to the 2004/2005 SOWER cruise, the Scientific Committee compared information from the SOWER vessel with that obtained from an icebreaker that operated in partly ice-covered waters. Estimated densities of minke whales in partly ice-covered areas and in open waters were not significantly different. Pending further analyses, the Committee agreed that there are indications of substantial densities of minke whales within the pack ice for the area covered, demonstrating the importance of accounting for whales within the ice field when estimating absolute abundance.

Updated abundance estimates using the standard IWC line transect methodology with some modifications were presented this year. For CPI, the central estimate was 645 thousand animals, for CPII it was 786 thousand and for CPIII it was 338 thousand. Thus the difference between CPII and III remains. However, although the Committee discussed possible reasons for the differences between minke whale abundance estimates from CPII and CPIII, it agreed that it is currently premature to advise on the extent of any decline in abundance.

Work to finalise an assessment of Antarctic minke whales is continuing in a number of ways and will again be a priority item for discussion at the 2007 meeting where the Scientific Committee hopes to be in a position to agree estimates.

5.1.2 Commission discussion and action arising
Australia expressed concern that the 60% reduction in abundance between CPII and CPIII remains unexplained, but looked forward to further work next year. Japan was pleased with the progress being made. It considered that there are now clearer indications that there are substantial numbers of minke whales within the pack ice and that this may be responsible for the lower numbers reported. It supported the Scientific Committee's work.

The Commission noted the Scientific Committee report and endorsed its recommendations.


5.2 Western North Pacific common minke whales

5.2.1 Report of the Scientific Committee
After the completion of the Implementation of North Pacific common minke whales in 2003, it was agreed that preparations should begin for an in-depth assessment of common minke whales in the North Pacific, with special emphasis on the J-stock.

This year the Scientific Committee agreed that there is now sufficient information available to begin specifying some plausible hypotheses for stock structure. The Committee continued to believe that it is very important to obtain information on the proportion of 'O' and 'J' stock animals in the Sea of Okhotsk and that the best way to achieve this is by biopsy sampling. Noting that permission had not been given for this during the 2003 survey, the Committee requested that the Commission urge the Russian Federation to give priority to granting the necessary permits to enable biopsy samples to be taken on surveys in the Sea of Okhotsk and other waters of their Exclusive Economic Zone (EEZ).

With respect to distribution and abundance, the Committee was pleased with the substantial intersessional progress made including receiving results from three cruises and a successful collaboration between Japanese and Korean scientists on genetic analysis. The Committee provided advice and recommendations for priorities for future surveys, further analytical work and telemetry and noted that obtaining abundance estimates from the un-surveyed areas will require co-operation from range states other than Japan and Korea. It re-iterated its recommendations of previous years that the Commission requests the Russian Federation to grant permission for sighting surveys to take place in the waters of their EEZ as a matter of priority. The Committee also made requests with respect to co-operation with Chinese scientists and fishing effort data from the Republic of Korea. It noted that this will be facilitated by a workshop of range state scientists being held in the Republic of Korea in late 2006.

5.2.2 Commission discussion and action arising
The Republic of Korea thanked the Scientific Committee for its work. It was pleased to hear that good progress had been made this year and expressed its gratitude to range states for their co-operation. However, the Republic of Korea was concerned to hear of difficulties encountered in surveys due to restricted access in some areas and reminded the Commission of Resolution 2005-2 adopted last year on facilitating closer co-operation among the range states to expedite the sighting survey on minke whales off the Korean Peninsula. Referring to the workshop mentioned in Resolution 2005-2, the Republic of Korea offered to host it in Ulsan in September 2006. It encouraged scientists from range states and others to take part. Japan noted its appreciation of the progress with the analysis of the J stock and reaffirmed its commitment to co-operating with other range states. It thanked the Republic of Korea for its offer to host the September 2006 workshop.

The Commission noted the Scientific Committee report and endorsed its recommendations.


5.3 Southern Hemisphere humpback whales

5.3.1 Report of the Scientific Committee
Last year, it was agreed that completion of the Comprehensive Assessment of Southern Hemisphere humpback whales at IWC/58 was a high priority. Substantive progress was made during an intersessional workshop held in Hobart, Australia in April 2006 and at the annual meeting towards completing the Comprehensive Assessment for three breeding stocks, i.e. A (eastern South America), D (western Australia) and G (western South America). The Scientific Committee agreed that there has been an observed increase in population size of Breeding Stock A in recent decades but that the stock remains well below pre-exploitation levels (i.e., 27-34%). No firm conclusions could be drawn regarding the status of Breeding Stocks D (because of the potential for exchange on the feeding grounds with breeding stock E found east of Australia) or G (because of the large variation in current abundance estimates) although the Committee agreed that both have shown substantial increase since protection. No further work can be undertaken on these until further information becomes available. The Committee has not yet been able to perform assessment modelling for Breeding Stocks B and C breeding off western and eastern Africa respectively and Breeding Stocks E and F breeding off eastern Australia and Oceania, because of uncertainty regarding stock structure. No abundance information is available for Breeding Stock X (a year-round resident of the Arabian Sea). High priority has been given to completing the assessment of Breeding Stocks B and C at next year's meeting.

5.3.2 Commission discussions and action arising
New Zealand indicated that it was grateful for the attention that the Scientific Committee has given to the Southern Hemisphere humpback populations because JARPAII will shortly target humpback whales. It recalled that last year, it had expressed deep concern about the potential impact of JARPAII takes on some of the very small and threatened populations that breed in the Pacific Islands region. New Zealand noted that these once-abundant stocks were brought to the brink of extinction by the whaling fleets of the 20th Century, and in its view, whales from these stocks should not be killed in order to be studied. New Zealand found the outcome of the Hobart workshop useful and informative, providing new information from non-lethal research on humpback whales in the South Pacific. It noted that the workshop report suggests that humpback whales of the Pacific Islands region are an aggregation of geographically and genetically distinct populations not previously recognised by IWC and that further information is required on the relationship between the Pacific Ocean breeding grounds and the Southern Ocean feeding grounds where JARPAII is conducted. New Zealand believed that to risk causing the extinction of one or more of these small vulnerable populations for 'so-called' research is not responsible.

Australia concurred with the comments of New Zealand. In particular, it noted with concern that the available data and analyses are not adequate to identify and differentiate where in the Southern Ocean the small and vulnerable Pacific Island populations feed. Australia believed that this means that JARPAII may well take humpback whales from very small populations.

Japan recalled that exactly the same points had been made last year and it was reluctant to repeat its previous response. However, for the record, Japan noted that in the Scientific Committee and at the workshop, no evidence had been presented that these small stocks around the Pacific Islands are coming into the research area of JARPAII. Japan reported that its research suggested that the takes of small numbers of humpback whales in the JARPAII area would not have any effect on the stocks.

The Commission noted the Scientific Committee report and endorsed its recommendations.


5.4 Southern Hemisphere blue whales

5.4.1 Report of the Scientific Committee
The Committee is beginning the process of reviewing the status of Southern Hemisphere blue whales. An important part of this work is to try to develop methods to identify pygmy blue whales from 'true' blue whales at sea and progress is being made on this. Work on genetic and acoustic differentiation techniques is continuing and there is considerable progress with morphological methods. The Committee has agreed previously that the Antarctic blue whale population: (1) is, on average, increasing at a mean rate of 7.3% per annum (95% CI 1.4-11.6%); (2) had an estimated circumpolar population size of 1,700 (95% CI 860-2,900) in 1996; and (3) is still severely depleted, with the 1996 population estimate estimated to be at 0.7% (95% CI 0.3-1.3%) of the estimated pre-exploitation level.

At this year's meeting, a Comprehensive Assessment was initiated. The Committee first considered past and present distribution of Southern Hemisphere blue whales. Data were presented suggesting that virtually all past catches occurred within the seasonal ice zone in waters less than 2°C, that abundance was uneven around the continent with greater abundance in the Atlantic, Western Indian Sector and to the north of the Ross Sea. Apart from in the Antarctic Peninsula area, abundance was highly correlated to the extent of the seasonal ice zone.

Surprisingly, correlation with krill density was lower. The Committee also received information from JARPA sightings, from fieldwork undertaken in the waters of southern Chile and from acoustic studies in the Indian and Southern Oceans. A number of recommendations for further work were made, particularly for the waters off Chile, with respect to acoustic studies and the completion of the major distributional review.

With respect to stock structure, the Committee reviewed preliminary results that confirmed its earlier view that only a very small proportion of pygmy blue whales might be found in Antarctic waters.

A new abundance estimate based on sightings from the JARPA surveys was received for the 2003/04 and 2004/05 seasons. It was some 1,300 animals for the area south of 60°S between 35°E and 145°W.

5.4.2 Commission discussion and action arising
Brazil congratulated the Scientific Committee for its work on blue whales and in particular the amount of information submitted to the Committee by Chilean scientists. Noting that Chile is considering establishing a Marine Protected Area for blue whales in its jurisdictional waters, Brazil commended this approach and indicated its willingness to co-operate formally. Argentina made similar comments. Chile thanked Brazil and Argentina for their remarks.

The Commission noted the Scientific Committee report and endorsed its recommendations.


5.5 Other small stocks - bowhead, right and gray whales

5.5.1 Report of the Scientific Committee
5.5.1.1 small stocks of bowhead whales
The Committee received information on the genetic relationships among bowhead whales based on samples collected in the waters of the eastern Canadian Arctic and Western Greenland, as well as samples from the BCB bowhead whales. There was considerable discussion on whether the putative Davis Strait/Baffin Bay and Hudson Bay/Foxe Basin stocks should be combined or remain separated. The Committee agreed that several lines of evidence pointed toward one stock, but that genetic data could still be interpreted to indicate two stocks. The Committee therefore noted that it would welcome a synthesis of the available data and consolidated analyses at next year's meeting to help it determine the relative plausibility of one and two stock hypotheses.

Results were presented from aerial surveys conducted in 2002, 2003 and 2004 in the eastern Canadian Arctic to estimate abundance in the putative Davis Strait/Baffin Bay and Hudson Bay/Foxe Basin stocks so as to develop a better understanding of the summering distribution of these whales. The Committee commended the Canadian and Greenland researchers for collecting much-needed information on these bowhead whales but agreed that some concerns need to be addressed before the abundance estimates could be accepted.

There were no reports of any catches in 2005.

5.5.1.2 north atlantic right whales
North Atlantic right whales are among the most endangered of all the large whales, with a remaining western North Atlantic population of around 300 animals. The Scientific Committee has recommended on a number of occasions that it is a matter of absolute urgency that every effort be made to reduce anthropogenic mortality in the North Atlantic right whale stock to zero. Right whales continue to die or become seriously injured by entanglements in fishing gear or ship strikes.

This year, the Committee received information on genetic analyses from bone samples that demonstrated that historical whaling markedly reduced the genetic variation in mitochondrial DNA.

5.5.1.3 southern hemisphere right whales
The Scientific Committee reviewed data for right whales off Australia and off South Africa. It was pleased to note information from western Australia, where the number of cow-calf pairs in 2005 was the highest recorded since surveys started (the annual series began off southern Western Australia in 1976 and expanded along the coast into South Australia from 1993). The rate of increase in the period 1993-2005 was over 7%. The Committee was also pleased that the number of cow-calf pairs recorded off South Africa in 2005 was the highest field count in 27 years of surveys. The Committee repeated its recommendation that these long-term monitoring programmes continue.

Reports were also received on right whale sightings and biopsy sampling during JARPA and IWC-SOWER cruises in 2005/2006.

5.5.1.4 western north pacific gray whales
The Scientific Committee and the Commission has expressed great concern over the critically endangered western gray whale on a number of occasions. The only known feeding grounds lie along the northeastern coast of Sakhalin Island, where existing and planned oil and gas developments pose potentially catastrophic threats to the population through habitat damage, ship strikes, noise and oil spills.

At this year's meeting, the Scientific Committee welcomed the provision, by the joint Russia-US programme, of a freely-available photo-identification catalogue containing images of 150 gray whales collected between 1994 and 2005 off Sakhalin Island. The Committee re-iterated its agreement from last year that scientists working as part of oil companies' research programmes should compare their photos with this catalogue and that potential new whales are reviewed by a group of experts before being added to the catalogue.

The Committee received conflicting advice on whether there had been any impact on gray whales due to construction and other activities related to the oil and gas industry off Sakhalin Island in 2005. Given the importance of this issue to the conservation of western gray whales, the Committee strongly requested that sufficient documentation is provided to allow it to evaluate the evidence next year.

The Committee received a report of the entanglement of a cow and a calf in a set net off the coast of Japan in July 2005. It was reported that the Japanese Fishery Agency has initiated actions to eliminate further anthropogenic mortality.

An updated population assessment was received based on photo-identification data from the Russia-USA programme. The estimated abundance is about 120 animals with a rate of increase of some 3% over the 1994-2005 period. The updated assessment is more optimistic than the previous assessment (i.e. less than 100 animals), mainly due to shorter calving intervals observed in recent years, implying a higher reproductive rate. However, the Committee noted that if whales continue to be entangled in nets at the 2005 level, then the population is predicted to decline, with a substantial risk of extinction by 2030.

Given the critical position of this population, the Scientific Committee stressed the urgency of reducing anthropogenic mortality in this population to zero and made a number of recommendations in this regard. The Committee agreed that the general issue of the use of telemetry and its potential effect on whales should be considered next year and that the need for a special workshop be considered.

Finally, the Committee recommended that the Commission request China to submit any information it may hold on the past and present occurrence of gray whales in its waters, where the breeding grounds are suspected to occur.

5.5.2 Commission discussion and action arising
Several countries thanked the Scientific Committee for its work. Discussions within the Commission focused on western North Pacific gray whales. The Netherlands recalled that last year, the Commission had adopted Resolution 2005-3 on western North Pacific gray whales that inter alia supported the recommendation for a comprehensive strategy to save this stock and its habitat. It expressed its increasing concern over the status of this stock and endorsed the Scientific Committee recommendations re-iterated from last year. Mexico associated itself with these remarks.

Austria echoed the Scientific Committee's concerns. It suggested that since the western North Pacific gray whale is one of the most endangered of large whale stocks, the reputation of IWC would somehow be put at stake if the organisation failed to protect it. Austria questioned whether the utmost effort is being made in this regard and whether there is optimal co-operation among range states, scientists and industry. It therefore called for great effort and active IWC participation, particularly with respect to reducing bycatch and promoting the exchange of data in general and on bycaught whales in particular.

The UK supported the remarks of previous speakers. Referring to Resolution 2005-3, it too urged that data be shared and that every effort be made to put mitigation measures in place. The USA noted that it considers the conservation of this stock to be critical and urged that the issue should not become politicised. It agreed that work needs to be done on samples from the whales stranded in 2005 and stressed that this should be undertaken by the laboratory holding the genetic samples and photographs.

As a range state, the Republic of Korea reported that it continues to provide information on its monitoring of the winter migration of gray whales in its waters. It believed that it is important to know the migration routes as well as the breeding grounds for this stock and was willing to co-operate with the Scientific Committee and relevant scientists.

In response to a question from Sweden on what measures it was taking to eliminate anthropogenic mortality of this gray whale stock, Japan reported that it instructs its local governments to instruct local fishermen not to obstruct the migration of these whales and to release any animals caught in nets. It was prepared to make the utmost effort to reduce bycatch.

The Commission noted the Scientific Committee report and endorsed its recommendations.

5 The IDCR/SOWER surveys between 1978/79 and 2003/04 have been grouped into three circumpolar sets of surveys, CPI, II and III.

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