Is the Japanese whaling fleet overfishing the Antarctic?

From IWC Report of the Scientific Committee 2011

On July 25, 2007 a The Sydney Morning Herald article stated :

Japan's whaling research body, the Institute of Cetacean Research, today said 91.6 per cent - or 262 of the 286 mature female minkes taken during the last hunt - were pregnant.

In June 2011 the International Whaling Commission (IWC) REPORT OF THE SCIENTIFIC COMMITTEE 2011 addressed the issue of declining Minke Whale stocks in the Antarctic:

WHALE STOCKS……..

Two different methods for estimating Antarctic minke whale abundance from these data have been developed in recent years (see below) and although they gave different estimates of abundance, both were consistent in showing an appreciable decline in estimated circumpolar abundance between CPII and CPIII……..

It is clear from Table 5 that while circumpolar Antarctic minke whale abundance estimates have declined during the period from CPII to CPIII, there are substantial differences in relative changes between Areas, with only relatively moderate increases or declines in some Areas, but appreciable declines in others (Table 6). No significant decline is seen in Areas III, IV and VI, whilst estimated abundance is substantially lower in CPIII for Areas I, II and V. Areas II and V encompass the Weddell and Ross Seas

As noted above, large declines in estimates of Antarctic minke whale abundance occurred in Areas I, II and V (there were no statistically significant changes in the other three Areas). The Committee agrees that these declines do indeed reflect genuine changes in abundance in the open-water areas surveyed that need to be explained. Such changes may be due to changes in distribution or reflect a true decline (or some combination of both)……

There are two classes of explanation for possible true declines in abundance. The first, quantitative approach involves the population dynamics statistical catch-at-age analyses (SCAA) from Area III East to VI West, which can potentially account for the changes in overall abundance in terms of variations over time in mortality and recruitment (note that this may explain how but not why changes occurred). The second, less quantitative approach involves attempts to identify mechanisms whereby mortality and recruitment may have changed (e.g. ecosystem effects, interspecies competition, climate changes, etc.).

It may be time to reflect on the fact that one of the management areas identified in the IWC report as experiencing an agreed marked decline in minke whale numbers is also one of those areas in which Japan’s whale fleet has actively hunted these whales, for at least twelve austral summer seasons during its approximately twenty-three year history of Antarctic commercial whaling conducted under the guise of scientific research.

During that time Japanese research documents show that the fleet has consistently taken both lactating and pregnant minke females.

From Polar Biology, Vol 31, Number 12

Click on image to enlarge

The Government of Japan’s whaling fleet is heading towards its Southern Ocean killing grounds as I write.

During the 2011/12 season the inappropriately named Institute of Cetacean Research will sponsor so-called ‘lethal research’ on as many as 930 minke whales and possibly a handful of fin whales and even humpbacks according to Japan Times Online on 11 December 2011. The IWC's own documents clearly indicate that the whaling fleet again intends to operate in one of the management areas showing significant minke whale decline.