Greattailed grackle

Quiscalus mexicanus

TAXONOMY

Corvus mexicanus Gmelin, 1788, Veracruz, Mexico. At least eight geographically discrete forms recognized.

OTHER COMMON NAMES

French: Quiscale a longue queue; German: Dohlengrackel; Spanish: Clarinero, Zanate Grande, Zanate Mayor.

PHYSICAL CHARACTERISTICS

10.5-18.5 in (26.5-47 cm); female 3.6-4.7 oz (102-132 g), male 6.2-8.9 oz (175-253 g). Sexually dimorphic in color. Males black glossed with purple on the head, becoming blue on the belly and back, and a yellow eye. They have a long keel-shaped tail. Females brown, with pale brown throat and stripe above the eye; geographically variable. Juveniles resemble females.

DISTRIBUTION

Resident in central California, central Colorado, and eastern Iowa, south to the Gulf coast south through Mexico and Central America to the coast of northwestern Venezuela and south to northwestern Peru. Some individuals from northern populations move south in winter.

HABITAT

Pastures, agricultural lands, second-growth scrub, mangrove forests, and secondary forests to 7,500 ft (2,300 m).

BEHAVIOR

Territorial during the breeding season. Males defend a territory with songs, "rough out" and "bill pointing" displays, and chasing. In winter, found in flocks.

FEEDING ECOLOGY AND DIET

Forage mostly on ground or low in vegetation. Foods taken vary seasonally, but diets consist principally of animal matter (especially grasshoppers and other insects).

REPRODUCTIVE BIOLOGY

Successful males mate with several different females in a single season. Females build the bulky, cup-shaped nest, which is placed above ground, generally as high as the vegetation permits. Generally 2-4 eggs are laid in January-July. Nesting commences earlier and clutch sizes are smaller in the south than in the north. Incubation takes 13-14 days; fledging about 16-19 days. Two broods may be produced in a single season.

CONSERVATION STATUS

Not threatened. Widespread and common, and its range is rapidly expanding northward in the Great Plains.

SIGNIFICANCE TO HUMANS

They may be considered agricultural pests in some areas; however, they eat many insects that could cause crop damage. ♦

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