Protected minke whales from unreported bycatch sold on Japanese markets

By Hilary Miller 06/09/2009 Japan kills over a hundred minke whales each year under the guise of ’scientific whaling’, and much of the meat ends up in the commercial markets destined for Japanese dinner plates.  Now a study just published in Animal Conservation indicates that a similar number of whales are killed as ’bycatch’ in Japanese coastal waters, and much of this catch is unregulated and goes unreported.

Scott Baker (University of Auckland and Oregon State University) and colleagues from New Zealand, Australia, USA and Japan used some genetic detective work to sample the whale meat sold on Japanese markets and found that 46% of the meat sold was of the protected ’J stock’.  Minke whales form 2 distinct groups that can be distinguished by their genetic makeup: the O stocks are found in offshore Pacific waters, and are the target of scientific whaling; and the J stocks are primarily found in coastal waters in the Sea of Japan and are largely killed as fisheries bycatch.  The J stocks were depleted as the result of intense whaling by Korea and Japan between 1962 and 1986 and have been protected since 1986.

Whales that are killed incidentally in fishing nets are reported by most member nations of the International Whaling Commission (IWC).  However, Japan and Korea are the only countries that allow the sale of these whales. In Japan, whale meat originating from bycatch was originally only allowed to be sold locally, but in 2001 a law change allowed fishers to legally kill, distribute and sell these whales.  Between 1997 and 2000 an average of 25 whales a year were reported as bycatch, but once the regulations were changed to allow their commercial sale, the reported bycatch suddenly increased about 4-5 fold to over 100 whales per year.

Baker and colleagues sampled meat from markets across Japan between 1997 and 2004.  Using mitochondrial DNA markers they were able to determine which species the meat came from, and for minke whales to determine whether the meat was from O or J stock whales.  They were also able to determine how many individual whales the samples represented by using a suite of microsatellite markers which are highly variable between individuals.

Baker and colleagues determined that the number of J stock animals sold on Japanese markets was fairly constant over the 1997-2004 period.  The estimated true take of J stocks from bycatch is more than 100 whales per year in Japanese waters alone.  This is at odds with the number reported as bycatch, particularly in the years before 2001 when only 19-29 animals per year were recorded, suggesting that a large amount of fisheries bycatch goes unreported.

Speaking after the scientific meeting of the IWC in June, Baker commented that the sheer number of whales represented by whale-meat products on the Japanese and Korean market suggests that both countries have an inordinate amount of bycatch.

’The sale of bycatch alone supports a lucrative trade in whale meat at markets in some Korean coastal cities, where the wholesale price of an adult minke whale can reach as high as $100,000,’ Baker said. ’Given these financial incentives, you have to wonder how many of these whales are, in fact, killed intentionally.’

Footnote: Much of the lab work for this study and others by Baker’s group is done using ’portable’ lab equipment which can be set up in Japanese hotel rooms. This gets around the problem of sending CITES-listed whale tissue overseas for analysis.  As an MSc student at Auckland University in the mid 1990s I remember hearing about this work and thinking it made molecular ecology seem all very James Bond and exciting.

Lukoschek, V., Funahashi, N., Lavery, S., Dalebout, M., Cipriano, F., & Baker, C. (2009). High proportion of protected minke whales sold on Japanese markets is due to illegal, unreported or unregulated exploitation Animal Conservation DOI: 10.1111/j.1469-1795.2009.00302.x
(Additional material from Science Daily)