Why some are there so many undernourished seal pups?

This is the result of too early separation from the female. The female feeds the baby an average of 5 weeks, after which the pup begins an independent life. He needs to build up enough  normal fat reserves before he starts to hunt productively, that is, until he learns to eat fish. Before fish seals eat low-calorie, but slow and accessible crabs, sea crustaceans and molluscs. For the undernourished seal pup it is not enough food, and it quickly loses fat.