Prey Species and Foraging Behaviour of Indo-Pacific Bottlenose Dolphins (Tursiops aduncus) Around Mikura Island in Japan
Rikiya Takahashi, Mai Sakai, Kazunobu Kogi, Tadamichi Morisaka, Takao Segawa, Hiroshi OhizumiDOI: 10.1578/AM.46.6.2020.531
Rikiya Takahashi (the first author) and co-authors reported about prey species and foraging behaviour of Indo-Pacific bottlenose dolphin (Tursiops aduncus) around Mikura island in Japan using underwater observation and stomach contents. In general, it is difficult to observe cetaceans behaviour in detail since they live underwater, but the water around Mikura island has high visibility and it makes ideal for underwater observation. This is the first study using underwater observations to assess foraging and prey species of small cetaceans in Japan. We confirmed over 15 species of fish or cephalopods as prey. This suggests that Indo-Pacific bottlenose dolphin around Mikura Island feed variety of organism as prey species. The sighting of daytime foraging was rare, and the prey included mesopelagic species suggests that they did active foraging during the night and early morning. Females were significantly more frequent to forage during the day than males. Additional data and detailed observations are needed to clarify the reasons for this in the future.
Takahashi R, Sakai M, Kogi K, Morisaka T, Segawa T, Ohizumi H (2020)Prey Species and Foraging Behaviour of Indo-Pacific Bottlenose Dolphins (Tursiops aduncus) Around Mikura Island in Japan Aquatic Mammals , 46(6): 531-541 10.1578/AM.46.6.2020.531