The glacial lakes of the northeast are abundant in waterfowl and water birds. Recent years have seen the glacial lakes as full as they have been in recent memory, if not longer. While this is good for some species, such as Western and Clark's Grebes, along with many species of ducks, geese, terns, herons, and egrets, it has apparently been disruptive for others. Notably, the Red-necked Grebe, a species whose only known breeding location in the state was in Waubay NWR, has apparently been driven from this location by high waters. Also notable for this area are breeding California Gulls, which are rare breeders in South Dakota.