The Baikal seal, also known as Lake Baikal seal or Baikal nerpa, is a species of earless seal endemic to Lake Baikal in Siberia, Russia. The Baikal seal is one of the smallest earless/true seals, and the only exclusively freshwater pinniped species. The related Caspian seal inhabits another large, inland body of water, the Caspian Sea. Both species are closely related to the ringed seal, which inhabits the Arctic Ocean.