We report the first study of sperm whale-fall ecosystems, based on mass sinking of whale carcasses at shelf depths in the northwest Pacific. We conducted three observations over a 2-year period on replicate sperm-whale carcasses implanted at depths of 219-254 m off the southern part of Japan from July 2003 to August 2005. The study was made possible by a mass stranding of sperm whales in January 2002, and the subsequent sinking of 12 carcasses in the waters off Cape Nomamisaki. Dense aggregations of unique chemosynthesis-based fauna had formed around the whale carcasses after 18 months (July 2003). The mytilid mussel Adipicola pacifica was the most abundant macrofaunal species and covered most of the exposed bone surfaces. The general composition of the fauna was similar to that of deep-water reducing habitats, but none of the species appearing in this study has been found at hydrothermal vents, cold seeps or deep-water whale falls. A new species of lancelet, which was the first record of the subphylum Cephalochordata from reducing environments, a new species of Osedax; a rarely encountered benthic ctenophore, and a rare gastropod species were discovered at this sperm whale-fall site. Benthic communities were similar across all the carcasses studied, although the body sizes of the whales were very different. The succession of epifaunal communities was relatively rapid and the sulphophilic stage was considerably shorter than that of other known whale falls.

The stomach contents from a female Longman's beaked whale (Indopacetus pacificus), which stranded on the coast of Kagoshima Prefecture, Kyushu, Japan, were examined. This is the first specimen of this species from Japan and also its northern-most record. The remains collected from the stomach consisted of numerous cephalopod beaks and lenses and a large number of unidentified nematodes. Ninety-nine upper beaks and 69 lower beaks from squid species were collected from the stomach. The lower beaks were used to identify squid prey species; five species were identified: Taonius pavo, Onykia loennbergi, Onychoteuthis borealijaponica, Chiroteuthis picteti, and Histioteuthis inermis. Taonius pavo was the most common species and accounted for 84% of the total beaks. Distribution data for these squid species suggest that this whale fed in the epipelagic to mesopelagic zones in the western North Pacific off the southern part of Japan. Stomach morphology was also examined. The presence of a main stomach with three connecting chambers and one pyloric stomach compartment was confirmed. It appears that the morphology of this species' stomach is similar to that found in Tasmacetus and Ziphius. This is the first report on the food habits, stomach anatomy, and parasites of Longman's beaked whale and contributes to a better understanding of their biology.

In total, 57 giant squid, Architeuthis dux, were found between January 2014 and March 2015 in Japanese coastal waters in the Sea of Japan. Occurrences were especially high around Sado Island and in Toyama Bay. All of the squid occurred individually, and 28 were found alive. The occurrences were categorized into three groups based on distance from the shore and the depth at which they were found: (1) washed ashore on a beach or found floating at the surface close to a beach (19 individuals); (2) caught in a fixed net set in coastal waters between 50 and 150 m depths (28 individuals); and (3) caught by bottom trawl or bottom gillnet fisheries several kilometers offshore between 200 and 300 m depths (ten individuals). Two size groups were recognized, one ranging between 80 and 160 cm dorsal mantle length (DML) with a mode at 110 cm and another larger than 160 cm DML. The sex ratio in the smaller group was nearly equal and the larger group was comprised of all females. The Sea of Japan was considered to be a large natural trap for giant squid migrating through southwestern Tsushima Strait.

Cetacean strandings in the moving images of the NHK archives collections. Yoshikazu Uni 1) , Akiko Yatabe 2) and Hajime Ishikawa 3) 1) 2) 3) We found 31 cetacean stranding events of 32 programs in the NHK Archives Collections (Kawaguchi City, Saitama Prefecture, Japan) from 1957 to 1989. One baleen whale and 14 toothed whale species (number) were identified from the events: gray whale Eschrichtius robustus (1), sperm whale Physeter macrocephalus (1), pygmy sperm whale Kogia breviceps (2), Cuvier's beaked whale Ziphius cavirostris (7), ginkgo-toothed beaked whale Mesoplodon ginkgodens (2), killer whale Orcinus orca (2), short-finned pilot whale Globicephala macrorhynchus (4), false killer whale Pseudorca crassidens (1) , melon-headed whale Peponocephala electra (1), Risso's dolphin Grampus griseus (4), bottlenose dolphin Tursiops truncatus (1), pantropical spotted dolphin Stenella attenuata (1), northern right whale dolphin Lissodelphis borealis (1) and Pacific white-sided dolphin Lagenorhynchus obliquidens (1). One Berardius sp. was also recorded. These events occurred in 9 prefectures; Hokkaido (1), Ibaraki (3), Chiba (8), Kanagawa (14), Mie (1), Aichi (1), Hyogo (1), Nagasaki (1) and Miyazaki (1). Cuvier's beaked whale was the most frequent and all events of this species were recorded in Kanagawa prefecture. It seems the numbers in locality dose not reflect frequency distribution of the events because the data source (NHK Archives Collections) has principally collected Kanto area local news. Of 31 events, 14 were not listed in the stranding database of Whale Laboratory, Institute of Cetacean Research and National Museum of Nature and Science. Except for the stranding events, rare pygmy killer whales Feresa attenuata were recorded in dolphin fishery in Futo in Shizuoka and in Taiji in Wakayama prefectures.