Abstract
Japan has no official institution to respond to stranding marine mammals. On the other hand, over 400 stranding events are reported annually in Japan (http://svrsh1.kahaku.go.jp/marmam/). The higher rank species in stranding records are pacific white-sided dolphin (Lagenorhynchus obliquidens), finless porpoise (Neophocaena phocaenoides), Risso's dolphin (Grampus griseus) and Stjnegers's beaked whale (Mesoplodon stjnegeri). Recently, the number of reports of Kogia sp. (Kogia sima and breviceps) is increasing. Most of the pacific white-sided dolphins and finless porpoises were caught in fishing nets. From the 1980's, the national museum of nature and science has concentrated on the stranding survey. It consists of external measurements, photographs, pathological examinations and samples and specimens collected.
We have investigated over 1000 individuals and stored more than 5000 specimens in the museum for about 15 years. A new species, Balaenoptera omurai8 and a rare species, Indopacetus pacificus9 were found and investigated in our stranding survey. Recorded external features of stranded individuals are cited for drawings for the poster 'whales of the world' in the museum. For marine mammal medicine, we examined about 400 individuals pathologically.4-7 Amyloidosis in two Stejneger's beaked whales,3 acute hemorrhagic pancreatitis in a harbor porpoise (Phocoena phocoena), pyometra in a fur seal (Callorhinus ursinus) and brucellosis in a rough-tooted dolphin (Steno bredanensis), which is a first pathological case from stranding individuals in Japan. Many suppurative and / or parasitic granulomatous pneumoniaes were also found in finless porpoises. Possible correlation between accumulation of BTs (butyl tin compounds) and status of pulmonary nematode infections,2 and between BFRs and hepatic torematoda infection1 in finless porpoise stranded in Japan was reported respectively. In addition, although we analyzed domoic acid, saxitoxin and brevitoxin from harmful algal blooms (habs) for 124 cetaceans, 20 species and 84 pinnipeds, by ELISA and pathological survey from 2009 to 2010, all samples were negative for both analyses. Other results such as contaminant analysis, molecular biology, life history and food habit are also obtained day by day from the stranding survey in Japan.
*Presenting author
Literature Cited
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