New publication: Baird, R.W., D.J. McSweeney, C. Bane, J. Barlow, D.R. Salden, L.K. Antoine, R.G. LeDuc and D.L. Webster. 2006. Killer whales in Hawaiian waters: information on population identity and feeding habits. Pacific Science 60:523-530. Abstract Killer whales (Orcinus orca) have only infrequently been reported from Hawaiian waters, and most of what is known about killer whales world-wide comes from studies in coastal temperate waters. Here we document 24 records of killer whales from within the Hawaiian Exclusive Economic Zone between 1994 and 2005. Killer whales were recorded 10 months of the year, most around the main Hawaiian Islands. While there were slightly more records than expected during the period when humpback whales are abundant around the islands, there is likely an increase in sighting effort during this period. Killer whales were documented feeding on both a humpback whale and cephalopods, and two species of small cetaceans were observed fleeing from killer whales. Although it is possible there are both marine mammal-eating and cephalopod-eating populations within Hawaiian waters, it seems more likely that Hawaiian killer whales may not exhibit foraging specializations as documented for coastal temperate populations, given the lower productivity and thus reduced selective pressure for specialization in tropical waters. Saddle patch pigmentation patterns were generally fainter and narrower than for those seen in killer whales from the temperate coastal North Pacific, though were most similar to the mammal-eating form of killer whale from those areas. Analysis of skin samples from two animals indicated two mitochondrial haplotypes, one identical to the "Gulf of Alaska transient 2" haplotype (a mammal-eating form), and the other a new haplotype one base different from haplotypes found for mammal-eating killer whales in coastal Alaskan waters. While more samples are needed, including samples from intervening areas, we suggest that killer whales around the Hawaiian Islands are likely isolated from populations in coastal temperate areas. PDF copies are available at http://www.cascadiaresearch.org/robin/hawaii.htm ======================================================== Robin W. Baird, Ph.D. Research Biologist Cascadia Research Collective 218 1/2 W. 4th Avenue Olympia, WA 98501 USA Phone 1-360-943-7325 Fax 1-360-943-7026 e-mail: [EMAIL PROTECTED] www.cascadiaresearch.org/robin/robin.htm
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