Interchanges and movements of humpback whales in Japanese waters: Okinawa, Ogasawara, Amami, and Hokkaido, using an automated matching system.

Humpback whales in the western North Pacific are considered endangered due to their small population size and lack of information. Although previous studies have reported interchanges between regions within a population, the relationship between the geographic regions of a population in Japan is poorly understood. Using 3,532 fluke photo IDs of unique individuals obtained from four areas in Japan: Hokkaido, six IDs (2009-2019); Ogasawara, 1,477 IDs, from two organizations (1) Everlasting nature of Asia (1987-2020) and (2) Ogasawara Whale Watching Association, (1990-2020); Amami, 373 IDs (1992-1994, 2005-2016); Okinawa, 1,676 IDs (1990-2018), interchanges were analyzed.