ESR prepress abstract   -  DOI: https://doi.org/10.3354/esr01349

ABSTRACT: North Pacific right whales Eubalaena japonica once numbered in the tens of thousands. Today, the eastern population is one of the most endangered large whale stocks in the world. A lack of dedicated surveys and a population in the tens of animals have resulted in considerable knowledge gaps. Here we collate all contemporary sightings of eastern North Pacific right whales (ENPRW) from 2006 through 2023 to investigate possible migratory routes and elucidate important habitat. Sightings in the northern Bering Sea, Gulf of Alaska, and along the west coast of North America have increased. Of the 99 sightings recorded between 2006 and 2023, 58 occurred during the few dedicated ENPRW surveys with simultaneous aerial and vessel platforms. All animals sighted were non-calves. Opportunistic sightings along the California coast were only reported in spring months (February–May). While this timing would coincide with a northward migration from lower latitudes, poor photo quality prevented matching of these animals, making it difficult to determine migratory patterns. Furthermore, there have been no sightings in Hawai’i or Mexico since 1996, and no sightings in the eastern North Pacific off the continental shelf since the 1970s. To date, only 2 animals have been photographically matched from Alaska to more southerly latitudes, and there have been no photographic matches between the Bering Sea and Gulf of Alaska. Feeding has been observed throughout their range, suggesting right whales opportunistically feed whenever possible. While their primary migratory destinations remain unknown, these recent sightings provide insight into important ENPRW habitat in Alaska.