Scaup is a type of diving duck that is widely distributed across the Northern Hemisphere. It is also known as a bluebill in North America. However, apart from these common names, there are several other synonyms for this waterfowl. In North America, it is sometimes referred to as a broadbill or a raft duck. In Europe, it is commonly known as the lesser scaup or the little bluebill. In Asia, it is called the greater scaup or the blackhead. Other regional names for scaup include raider, ringneck, and bluenose. Regardless of the name, the scaup is a graceful and elegant bird that is known for its diving ability and its striking plumage.