San Francisco is one of America's most popular tourist destinations, but it's recently been drawing in a crowd for a very different reason. A huge and very confident sea lion - nicknamed Chonkers by locals - has taken over part of the busy waterfront in the city. He's become a bit of a local celebrity, with people travelling from across the country to watch the 1,000kg sea lion as he relaxes, barks and naps in the sunshine. Chonkers isn't the usual type of sea lion spotted there, and experts say that's one of the reasons why he's causing such a splash. Chonkers first appeared at San Francisco's Pier 39 around a month ago, when he hauled himself onto the pier and decided to stay. While Californian sea lions can typically be seen in the area, there's something extra special about Chonkers, which helped make him a star. That's because he is a Steller sea lion, and he quickly stood out for his huge size.