There are three types of bird's nests: Snow Bird's Nest, Hairy Bird's Nest, and Blood Bird's Nest. The best bird's nest is the one produced in Gongsong Island. The Snow Bird's Nest is the first nest prepared by the swiftlet for laying eggs, and is made from the secretions of the sea baths and small fishes that are digested in the stomach. When it is harvested. When it is close to the egg-laying period, it will make another one in a short time, but the quality of this time is not as good as the first one, which is mixed with some impurities of hairs and undigested fish and shrimps from the sea bath.