Multiple visits of individual humpback whales (Megaptera novaeangliae)between the Hawaiian and Japanese winter grounds

摘要

We document through photographic identifications three humpback whale (Megaptera novaeangliae) winter ground interchanges between Hawaii and Japan. Two of these whales, identified as male by their behavioral roles, made multiple interchanges across years; i.e., they were initially seen in Hawaii, were later observed in Japan, and subsequently, returned to Hawaii. The third whale was seen in only 2 different years, once in Japan and then in Hawaii. Prior to this report, there has been only one published report of a Hawaii-Japan interchange and only eight between Hawaii and Mexico. None of these involved multiple interchanges. The current findings demonstrate that individual whales may be highly flexible in their annual choice of widely separated winter destinations and suggest that these wanderers may be mainly males. The occurrence of wanderers provides a mechanism for increasing genetic variability in the breeding populations and also suggests a mechanism for noted song similarities across different North Pacific winter grounds.