Bitterns

The American bittern (Botaurus lentiginosus) breeds in freshwater and brackish marshes over most of the temperate zone of North America, and as far south as central Mexico. Most North American populations migrate to the southern United States and Central America to spend their non-breeding season. American bitterns mostly eat fish, but they will also predate on other appropriately sized, aquatic prey. Male American bitterns have a distinctive song in the springtime, when they are establishing a breeding territory and attempting to attract a mate. This booming call can be heard over a distance of several miles, and more or less sounds like a pumping, "ong-ka-chonk." Some local names of the American bittern reflect its call: "thunder pump" and "stake driver." Other species of Botaurus occur in nonoverlapping ranges on other continents. These species are all rather similar, and although considered to be taxonomically distinct, they form a closely-related, "superspecies." The other species of bitterns include the Eurasian bittern (Botaurus stellaris) of Europe and Asia, the Australian bittern (B. poiciloptilus), and the South American bittern (B. pinnatus).

The least bittern (Ixobrychus exilis) is the smallest species of heron in North America. This secretive species breeds widely in freshwater and coastal marshes in the eastern United States and southeastern Canada. Least bitterns also breed in a disjunct, western range in California An American bittern in Florida. JLM Visuals. Reproduced by permission. and Oregon, and south to Brazil, Paraguay, and northern Argentina. Northern populations of the least bittern migrate to northern Mexico and Baja California for the winter. The least bittern mostly feeds on small fish, which it stalks patiently and then spears with its bill.

The various species of Ixobrychus also have nonoverlapping ranges, and also form a closely-related "superspecies." The species include the little bittern (I. minutus) of Europe, Asia, Africa, and Australia, and the Chinese little bittern (I. sinensis) of eastern Asia.