Sploid has a story about a baby seal spotted alone, by the water (or maybe not, because pictures either do or do not lie) in Sweden. Diaz castigates bystanders for not doing anything for the poor baby seal. Here's his response to someone who tries to correct his sense of geography. Granted, personal experience is not a substitute for facts, but it seems a weirdly assured response.
I don't know what I'd do in a situation like this. Certainly I'd call animal control, but I have this weird notion (maybe from childhood) that it is bad for some animals to have human smells on them, so I wouldn't touch the seal.