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Mink whale
Mink whale. Foto: Lars Maltha Rasmussen
Humpback whale
Humpback whale. Foto: Fernando Ugarte.

Large whale management advice from the IWC Scientific Committee 2008

West Greenland common minke whale

In 2007, the Commission agreed to a quota of 200 minke whales struck annually off West Greenland in part based on the range 170-230 advised by the Committee. The Committee again stresses that it has made great progress towards being able to provide firm management advice for this stock. In particular, there is an accepted abundance estimate from the 2005 aerial survey of 10,800 (95% CI=3,600-32,400). In addition, considerable progress was made at both the intercessional workshop (SC/60/Rep2) and the present meeting on developing an assessment method incorporating the available sex ratio data. With a further intercessional workshop, it should be possible to finalize work on the applicability of sex ratio data to provide management advice at the 2009 Annual Meeting. Should this work prove successful, it would also represent an important step forward towards the development of a full SLA approach for providing long-term advice.

In terms of advice this year, the 2005 abundance estimate is not statistically significantly different from the 1993 estimate accepted by the Committee, although the power to detect differences is low owing to low precision. Questions about stock structure remain. Although the survey estimate does not apply to the whole population, it is still not presently possible to determine by how much it is an underestimate. This issue will be addressed should the proposed assessment method prove to be applicable next year. However, despite the great improvement in the situation compared to previous years, the Committee remains concerned that it is not in a position to give authoritative advice on safe catch limits this year. Given that, it agrees that it is not possible for it to give more than interim ad hoc advice for the forthcoming season, noting that it believed that there was a reasonable chance that it would be in a position to provide them advice next year. It notes that last year it had recommended that any quota established by the Commission on the basis of the interim ad hoc advice below be limited to one year only.

Until the work on the sex-ratio methods is completed next year, the Committee is therefore in the same position as in the past two years. It again stresses that the Commission should exercise caution when setting catch limits for this stock. The Committee thus is not in a position to recommend a single number, but repeats its previous advice to the Commission: under the assumption that (a) MSYRmat is 3%; (b) that the true population has a sex ratio of 1:1; and (c) that the population is underestimated by factors between 2 and 2.7, the estimated annual replacement yield ranges from about 170 to 230 whales if the lower bound of the revised 2005 aerial survey estimate is used. The replacement yield is the catch level yielding no net increase in abundance.

It re-emphasizes its view that safe long-term management of aboriginal whaling is best accomplished under an agreed AWMP SLA. It therefore agrees that development of an SLA for this fishery should begin as soon as practical (see Item 8.2).

East Greenland common minke whale

In 2007, the Commission agreed to a quota of 12 minke whales struck annually from the stock off East Greenland for 2008-12, which the Committee stated was acceptable in 2007. The present catch limit represents a very small proportion of the Central Stock (see Table 5). The Committee agrees that the present catch limit will not harm the stock.

West Greenland fin whale

In 2007, the Commission agreed to a quota (for the next five years) of 19 fin whales struck annually off West Greenland based the range 14-26 advised by the Committee last year.

This year, the Committee was pleased to have developed an agreed (option C) approach for determining interim management advice for this stock and the details are provided under Item 8.2 and Annex E (Appendix 2). Given this, the Committee agrees that the current strike limit will not harm the stock. The abundance estimate on which this calculation was based was the agreed estimate of 4,656 (CV=0.46).

Eastern Canada-West Greenland bowhead whale

In 2007, the Commission agreed to a quota (for the next five years) of two bowhead whales struck annually off West Greenland but the quota for each year shall only become operative when the Commission has received advice from the Scientific Committee that the strikes are unlikely to endanger the stock.

This year, the Committee was pleased to have developed an agreed (option C) approach for determining interim management advice for this stock and the details are provided under Item 8.2 and Annex E (Appendix 2). Given this, the Committee agrees that the current catch limit will not harm the stock. It was also aware that catches from the same stock have been taken by a nonmember nation, Canada. It noted that should Canadian catches continue at a similar level as in recent years, this would not change the Committee’s advice with respect to the strike limits agreed for West Greenland.

West Greenland humpback whale

Last year, the Committee had been unable to provide management advice for the humpback whale aggregation off West Greenland. This year, the Committee was pleased to have developed an agreed (option C) approach for determining interim management advice for this feeding aggregation and the details are provided under Item 8.2 and Annex E (Appendix 2). Given this, the Committee agrees that strikes of up to 10 humpback whales will not harm the stock.

Updated 03.31.2011