Redhead

Ducks in general often lay eggs in the nests of others, but the Redhead carries this to extremes. Female Redheads regularly parasitize each others' nests, as well as the nests of at least 10 other duck species. They also have been known to lay eggs in the nests of American Bittern, and even of the predatory Northern Harrier! Some females may be entirely parasitic, never incubating their own eggs. Such behavior is abetted by the social tendencies of the species, with many often nesting in close proximity. In winter, impressive flocks of Redheads concentrate on coastal lagoons; such gatherings may run to tens of thousands of individuals in the Laguna Madre of southern Texas and northeastern Mexico.