American Bittern

Identificazione

The American bittern is a large, chunky, brown bird, very similar to the Eurasian bittern (Botaurus stellaris), though slightly smaller, and the plumage is speckled rather than being barred. It is 58–85 cm (23–33 in) in length, with a 92–115 cm (36–45 in) wingspan and a body mass of 370–1,072 g (0.816–2.363 lb).<p>The crown is chestnut brown with the centers of the feathers being black. The side of the neck has a bluish-black elongated patch which is larger in the male than in the female. The hind neck is olive, and the mantle and scapulars are dark chestnut-brown, barred and speckled with black, some feathers being edged with buff. The back, rump, and upper tail-coverts are similar in color but more finely speckled with black and with grey bases to the feathers. The tail feathers are chestnut brown with speckled edges, and the primaries and secondaries are blackish-brown with buff or chestnut tips. The cheeks are brown with a buff superciliary stripe and a similarly colored mustachial stripe. The chin is creamy-white with a chestnut central stripe, and the feathers of the throat, breast, and upper belly are buff and rust-colored, finely outlined with black, giving a striped effect to the underparts. The eyes are surrounded by yellowish skin, and the iris is pale yellow. The long, robust bill is yellowish-green, the upper mandible being darker than the lower, and the legs and feet are yellowish-green. Juveniles resemble adults, but the sides of their necks are less olive.

Tassonomia

The American bittern was first described in 1813 by the English clergyman Thomas Rackett from a vagrant individual he examined in Dorset, England. No extant subspecies are accepted. However, fossils found in the Ichetucknee River in 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. Its closest living relative is the pinnated bittern (Botaurus pinnatus) from Central and South America.<p>The generic name Botaurus was given by English naturalist James Francis Stephens, and is derived from Medieval Latin butaurus, "bittern", constructed from the Middle English name for the Eurasian bittern, botor. Pliny gave a fanciful derivation from Bos (ox) and taurus (bull), because the bittern's call resembles the bellowing of a bull. The species name lentiginosus is Latin for "freckled", from lentigo (freckle), and refers to the speckled plumage.<p>Many folk names are given for its distinctive call. In his book on the common names of American birds, Ernest Choate lists "bog bumper" and "stake driver". Other vernacular names include "thunder pumper", "bog bull", "bog thumper", "mire drum", and "water belcher".

Nome scientifico

Botaurus lentiginosus

Autorità

(Rackett, 1813)

Ordine

Pelecaniformi

Famiglia

Ardeidae

Genere

Botaurus

Areale e habitat

Its range includes much of North America. It breeds in southern Canada as far north as British Columbia, the Great Slave Lake and Hudson Bay, and in much of the United States and possibly central Mexico. It migrates southward in the fall and overwinters in the southern United States of the Gulf Coast region, most notably in the marshy Everglades of Florida, the Caribbean Islands and Mexico, with past records also coming from Panama and Costa Rica. As a long-distance migrant, it is a very rare vagrant in Europe, including Great Britain and Ireland. It is an aquatic bird and frequents bogs, marshes and the thickly-vegetated verges of shallow-water lakes and ponds, both with fresh and brackish or saline water. It sometimes feeds out in the open in wet meadows and pastures.

Areale riproduttivo

America settentrionale: ampiamente distribuito

Areale non riproduttivo

MA and Caribbean

Migrazione

Migratori completi

Comportamento

Comportamento migratorio: Migratori completi.

Conservazione

Tendenza della popolazione: in diminuzione.

Tendenza della popolazione

in diminuzione