Goggle-eyed “dogs” of the ocean, seals and sea lions receive much playful attention from divers who travel the world to see them. Often treated much like their topside doppelgängers, pinnipeds are able to demonstrate an understanding of transitivity and simple syntax, and have been taught simple tricks by travelling circus trainers and zookeepers for centuries. To help you fin-kick your way to finding your very own underwater companion, we bring you eight of the best places to dive with them.

Star of Free Willy, and now immortalised once again in the heartrending documentary Blackfish, do these charming whales really deserve the name “killer”?