Common Loon (Gavia immer) with young on Thompson Lake in Casco, Maine. During the winter, this beautiful water bird can be found in warm areas around the Gulf of Mexico and on the east and west coasts of North America. In spring, the common Loon migrates to breeding grounds throughout Canada and the northern most states of the U.S. It is during the spring and Summer time that northern lakes and waterways are haunted with the strange falsetto wails, yodeling, and laughter-like calls of Gavia immer. The Common Loon can swim quite swiftly underwater and will sometimes dive to depths of over 90 feet to catch fish upon which it feeds.