Where do the Chukchi Sea fin whales come from? Looking for answers in the structure of songs recorded in the Bering Sea and Western North Pacific.

Abstract

Fin whales are common throughout the North Pacific and have recently been detected acoustically as far north as the northeastern Chukchi Sea. Non‐acoustic evidence suggests that North Pacific fin whales are segregated into two populations wintering along the Asian and North American coast with at least some animals intermingling in the summer in the Bering Sea‐Aleutian Islands area. Male fin whales produce regionally distinctive songs which are likely indicative of population structure. In this study we evaluated the relationship of fin whales recorded in the northeastern Chukchi (2007 and 2009) and southeastern Bering (2007–2008) seas by comparing the structure of their song. Additionally, we investigated whether fin whales detected in these areas could be part of an Asian population by comparing their songs to those recorded near the Emperor Seamounts in the western North Pacific (2007). The results will be discussed in light of the current knowledge on North Pacific fin whale population structure.