Seal or sea lion: the question has plagued zoo-goers and amateur marine biologists for decades. They sure look similar, and does anyone even really care if you mix them up? Maybe not, but if you want to be able to impress your friends and family, here’s how you can tell the difference between a seal and a sea lion.
First, we can talk about the similarities: seals and sea lions do have very similar appearances, and it’s all because they belong to the same family. Seals and sea lions are both part of the pinniped group of animals; pinniped is Latin for “fin feet”, a fairly accurate description of the fin-like “arms” of seals and sea lions. Walruses are also members of the pinniped group, but you probably don’t have much difficulty telling walruses apart from their smaller, sleeker brethren.
Now for the differences: physically, the most visually obvious difference is that sea lions have ear flaps covering their ears, while seals just have holes on the sides of their heads. Some less obvious cues include the formation of their front feet and flippers. Seals, who spend the vast majority of their life in the water, are built to be more agile and aquadynamic, with stubby feet and backwards flippers that make them cumbersome on land. Sea lions, on the other hand, are often found lounging on land and have large feet and powerful, forward-facing hind flipper that make it easier to move around on land. Sea lions are also noticeable larger than seals.
Social habits can also help you tell a seal from a sea lion: seals don’t socialize much and prefer to stay on their own, living in the water most of the time. Sea lions are very social and can be found in herds as large as 1500; you can’t miss the sound of their loud barking as they communicate.