北海道にストランディングしたコマッコウの胃内容物

Pygmy sperm whale Kogia breviceps is found in temperate to tropical areas throughout the world. In Japan, it is often reported to have stranded ashore on the Pacific side of Honshu Island, but only six individuals have been reported in Hokkaido. Its feeding habits in the waters surrounding Japan have not been reported. In this study, the stomach contents of three pygmy sperm whale individuals stranded on the Pacific coast of Hokkaido from 2011 to 2014 were investigated. As a result, ten species of cephalopods from 8 families and one species of fish were found. All individuals fed on cephalopod of the family Gonatidae and Watasenia scintillans, Gonatus pyros, and Chiroteuthis calyx appeared from two out of three individuals. The largest percentage (73.0%) of the total number of prey species belonged to the family Gonatidae spp., followed by Watasenia scintillans (6.2%) and Chiroteuthis calyx (3.4%). Only one individual fed on fish, which were identified as Gadus chalcogrammus. The size composition of the prey showed that the smallest prey was Chiroteuthis calyx with a dorsal mantle length of 29.4 mm and the largest prey was the Galiteuthis phyllura with a dorsal mantle length of 420.2 mm. These results indicate that the pygmy sperm whale use mainly mesopelagic cephalopods off the coast of Hokkaido

1992年から2002年における北海道松前町の鯨類漂着記録（短報）

We received the whale stranding records from Matsumae-cho, Hokkaido, for the period 1992-2002 in 2013. Species and sex were identified as far as possible from the photographs provided. As a result of the identification, 11 individuals (SNH13901 to SNH13911) were obtained in 11 cases: nine individuals of Stejneger's beaked whales, one Baird's beaked whale, and one minke whale

Diphyllobothrium stemmacephalum (Cestoda: Diphyllobothriidae) found from a harbor porpoise in northern Japan, with comments on a geographical gap with human infection cases in southern Japan

Even though the cetacean tapeworm Diphyllobothrium stemmacephalum occurs in both cold and warm waters, human infections and final host occurrences have been confined to temperate areas in and near Japan. We recently obtained a strobila of this cestode that was excreted from a harbor porpoise accidentally caught offshore of Hokkaido of northern Japan. Genetic analysis of 28S rDNA and cox1 genes confirmed that the cestode was D. stemmacephalum. Our finding sets the northernmost record of D. stemmacephalum in the western Pacific, suggesting that the risk of human infections by this parasite in northern Japan deserves further attention