No Fin, No Cry

Belugas, like their northern relative the narwhal, do not have a dorsal fin. Why don’t Arctic whale species have this back fin when so many southern whale species do?

No dorsal fin means less surface areas for heat loss and easier swimming below the sheets of sea ice to locate breathing holes. Belugas do have a tough dorsal ridge which can be used to break sea ice, as well as a thick layer of blubber to keep them warm in the icy water. Their motto: No dorsal fin, no problem!