The effect of a harmful algal bloom (Karenia selliformis) on the benthic invertebrate community and the sea otter (Enhydra lutris) diet in eastern Hokkaido.

In recent decades, the locally extinct sea otter (Enhydra lutris lutris) has been recolonizing the coast of eastern Hokkaido. Their diet includes benthic invertebrates such as bivalves, sea urchins, snails, and chitons. In the fall of 2021, a harmful algal bloom (HAB) of Karenia selliformis occurred across Hokkaido's northern and eastern coasts, leading to a massive mortality of sea urchins.