Tuesday 16 August 2011

American Bittern

It is a large, chunky, brown bird, very similar to the Eurasian Great Bittern, Botaurus stellaris. It is 59–70 cm (23-27 inches) in length, with a 95–115 cm (37 - 45 inch) wingspan. Although common in much of its range, the American Bittern is usually well-hidden in bogs, marshes and wet meadows. Usually solitary, it walks stealthily among cattails or bulrushes.

If it senses that it has been seen, the American Bittern becomes motionless, with its bill pointed upward, causing it to blend into the reeds. It is most active at dusk. More often heard than seen, this bittern has a call that resembles a congested pump. Like other members of the heron family, the American Bittern feeds in marshes and shallow ponds, dining on amphibians, fish, insects and reptiles. This bittern winters in the southern United States and Central America. It summers throughout Canada and much of the United States.

As a long-distance migrant, it is a very rare vagrant in Europe, including Great Britain and Ireland. This bird nests in isolated places with the female building the nest and the male guarding it. Two or three eggs get incubated by the female for 29 days, and the chicks leave after 6–7 weeks. No subspecies are accepted today.

However, fossils found in the Ichetucknee River, Florida, and originally described as a new form of heron (Palaeophoyx columbiana; McCoy, 1963) were later recognized to be a smaller, prehistoric subspecies of the American Bittern which lived during the Late Pleistocene (Olson, 1974) and would thus be called B. l. columbianus. This bird's numbers have declined in the southern parts of its range due to habitat loss.