Baikal Seal at Zoo Leipzig, also known as "Leipzig Zoological Garden" (Germany)
The Baikal Seal (also known as Lake Baikal Seal or Nerpa) is a species of earless seal endemic to Lake Baikal in Siberia, Russia.
Like the Caspian seal, it is related to the Arctic ringed seal. The Baikal seal is one of the smallest true seals and the only exclusively freshwater pinniped species. It remains a scientific mystery how the seals originally came to Lake Baikal, hundreds of kilometers from any ocean.
Some scientists speculate the seals arrived at Lake Baikal when a sea-passage linked the lake with the Arctic Ocean.