Physical characteristics

Magpie-shrikes are large songbirds with pied (black-and-white) or blackish plumage and straight, powerful bills. Color is varied with red in only two groups: on the rump, lower belly, and undertail in peltopses and over the head in the bristle-head. Bristleheads are otherwise dusky-gray, stout, and short-tailed, while the small, flycatcher-like peltopses are long-tailed and black with large patches of white on their faces and backs. Currawongs, however, are big but slender crow-sized birds with long, white-tipped tails, rounded wings, startling yellow eyes, and dark gray to blackish plumage broken by patches of white in wings and under the tail. Australian magpies are pied, with black undersurfaces and pied uppersurfaces, and are short in tail, pointed in wing, and long in leg-all adaptations to life in open spaces. Although also basically pied, butcherbirds vary more, from all-black to black-hooded with white patches to wholly white with black, gray, and white patterning. Like magpies, butcherbirds are mid-sized magpie-shrikes with chestnut eyes and bicolored bills; the tip of the bill is blackish and the base whitish or pale bluish gray, while the bills in currawongs, peltopses, and bristleheads are black. Juveniles share the adults' plumage, although it is much duller and grayer, particularly in some butcherbirds. Depending on species or subspecies, fledglings may be rusty-brown, washed olive-yellow, or lack clear head-patterning. They also have uniformly dull gray bills.

Size varies from small (6.7-7.9 in [17-20 cm] long, 1.1-1.2 oz [30-35 g]) in the peltopses to very large in the Tasmanian gray currawong, Strepera versicolor arguta (19.7-21.7 in [50-55 cm] long, 16.2-17.6 oz [460-500 g]). As with most other crowlike birds, magpie-shrikes have a single pneumatic depression in the head of the humerus, as well as 12 tail feathers, 10 primary flight feathers (the tenth is usually well-developed), and 10 secondaries (11 in the Australian magpie). Also characteristic are the lack of a gap in the dorsal (back) feather tract and small perforations in the skull above the opening for the nerves of the eye; unusually strong black feet with booted or scaled legs; and powerful bills that range from notched and hooked to pick-shaped at the tip and are swollen at the base of the upper jaw, which lacks bristles and in which the nostrils are sunk in deep bony slits.

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