Understanding The Situation
It's best to contact an experienced marine mammal rescue organization before attempting to rescue a seal, sea lion or any other marine mammal. Trained rescuers will assess the situation and determine whether intervention is necessary.
It' s normal for seals and sea lions (pinnipeds) to spend time on land, and so seeing one onshore doesn't necessarily mean a rescue is needed. 30-40 percent of their time may be spent ashore: resting; socializing; escaping predators; giving birth and nursing or warming themselves in the sun. Some species will mate on land as well.
If you see a pinniped on land, don't try to coax, pull or push it back into the water. Seals and sea lions are wild animals, and approaching too closely can cause them undue stress. If they feel threatened, they may bite (even small pups!). Keep them and yourself safe by staying back as far as possible (the Canadian Marine Mammal Regulations specify a distance of 100 metres).
It's also important to keep pets away. Dogs may inflict wounds on marine mammals, and there's a risk of disease transmission between the species.