H.J. Ruiz – Avian101

Brown Thrasher

The Brown Thrasher (Toxostoma rufum) is a bird in the family Mimidae, which also includes the New World catbirds and mockingbirds. The dispersal of the brown thrasher is abundant throughout the eastern and central United States, southern and central Canada, and is the only thrasher to live primarily east of the Rockies and central Texas. As a member of the genus Toxostoma, the bird is a large-sized thrasher. It has brown upper parts with a white under part with dark streaks. Because of this, it is often confused with the smaller wood thrush (Hylocichla mustelina), among other species. The brown thrasher is noted for having over 1000 song types, and the largest song repertoire of birds.However, each note is usually repeated in two or three phrases.

The brown thrasher is an omnivore, with its diet ranging from insects to fruits and nuts. The usual nesting areas are shrubs, small trees, or at times on ground level. Brown thrashers are generally inconspicuous but territorial birds, especially when defending their nests, and will attack species as large as humans.

The brown thrasher is bright reddish-brown above with thin, dark streaks on its buffy underparts. It has a whitish-colored chest with distinguished teardrop-shaped markings on its chest. Its long, rufous tail is rounded with paler corners, and eyes are a brilliant yellow. Its bill is brownish, long, and curves downward. Both male and females are similar in appearance. The juvenile appearance of the brown thrasher from the adult is not remarkably different, except for plumage texture, indiscreet upper part markings, and the irises having an olive color.

The brown thrasher is a fairly large passerine, although it is generally moderate in size for a thrasher, being distinctly larger than the sage thrasher (Oreoscoptes montanus) but similar or somewhat smaller in size than the more brownish Toxostoma species found further west. Adults measure around 23.5 to 30.5 cm (9.3 to 12.0 in) long with a wingspan of 29 to 33 cm (11 to 13 in), and weigh 61 to 89 g (2.2 to 3.1 oz), with an average of 68 g (2.4 oz).  Among standard measurements, the wing chord is 9.5 to 11.5 cm (3.7 to 4.5 in), the tail is 10.9 to 14.1 cm (4.3 to 5.6 in), the culmen is 2.2 to 2.9 cm (0.87 to 1.14 in) and the tarsus is 3.2 to 3.6 cm (1.3 to 1.4 in).There are two subspecies: the ‘brown thrasher’ (T. rufum rufum), which lies in the eastern half of Canada and the United States, and the ‘western brown thrasher’ (T. rufum longicauda (Baird, 1858))  which resides in the central United States east of the Rocky Mountains and southern central Canada. The western brown thrasher is distinguished by a more cinnamon upper part, whiter wing bars, and darker breast spots than T.rufum rufum.

The brown thrasher has been observed either solo or in pairs. The brown thrasher is usually an elusive bird, and maintains its evasiveness with low-level flying. When it feels bothered, it usually hides into thickets and gives cackling calls. Thrashers spend most of their time on ground level or near it. When seen, it is commonly the males that are singing from unadorned branches. The brown thrasher has been noted for having an aggressive behavior, and is a staunch defender of its nest. However, the name does not come from attacking perceived threats, but is believed to have come from the thrashing sound the bird makes when digging through ground debris. It is also thought that the name comes from the thrashing sound that is made while it is smashing large insects to kill and eventually eat.

The brown thrasher is the state bird of Georgia.

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© HJ Ruiz – Avian101