Pygmy sperm whale (Kogia breviceps)

The objectives of this study were to report the results of recent analyses of environmental toxicants in Washington marine mammals and evaluate the evidence for pollutant-related effects in marine mammals. In the last eight years, samples of close to 100 marine mammals from Washington State have been analyzed for concentrations of the chlorinated hydrocarbons: polychlorinated biphenyls (PCBs) and 2,2-bis- (p-chlorophenyl)-1,1-dichloroethylene (DDE).

Cascadia responded to 81 cetacean strandings of at least 11 species during the grant period. These documented the post UME rate of mortality in gray whales which showed low levels of mortality in the years immediately following a major mortality event in 1999-2000 but which was slightly elevated above average in 2005 and 2006. We documented a continued occurrence of fin whale mortalities related to ship strikes.

Sightings of dwarf (Kogia sima) and pygmy (K. breviceps) sperm whales in Hawaiian waters have only rarely been reported. As part of boat-based surveys of odontocete cetaceans around the main Hawaiian Islands between 2000 and 2003, Kogia were observed on 18 occasions. Kogia were sighted most frequently in deeper portions of the study area (mean depth, 1,425 m) and in calm sea conditions (mean Beaufort sea state, 0.8).

The biology and ecology of the pygmy sperm whale (Kogia breviceps) is poorly understood among odontocetes (McAlpine 2002). In Hawaiian waters, pygmy sperm whales are the second most frequently recorded stranded cetacean species, with 35 strandings documented between 1963 and 2008 (Shallenberger 1981, Nitta 1987, Maldini et al. 2005, NMFS database1). Despite the high frequency of strandings, sightings of this species in Hawaiian waters are rare (Baird 2005).

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