Molothrus rufoaxillaris
The Screaming Cowbird (Molothrus rufoaxillaris) is a medium-sized passerine, measuring approximately 18-20 cm (7-8 inches) in length, and weighing around 40-50 grams. Adults exhibit a glossy, iridescent black plumage, with males displaying a slightly more intense sheen. Its most distinctive field mark, and the source of its scientific epithet 'rufoaxillaris,' are the striking rufous-chestnut feathers visible in the axillaries (underwings) during flight, and sometimes subtly at rest. Females a...
Primarily found in open woodlands, savannas, grasslands with scattered trees, and often in close association with human-modified landscapes such as pastures, agricultural fields, and suburban areas. It inhabits low to mid-elevation ranges across its South American distribution.
Their diet primarily consists of insects, such as grasshoppers, beetles, and larvae, gleaned from the ground, supplemented by seeds and occasionally small fruits.
Screaming Cowbirds are diurnal, often observed foraging on the ground in mixed-species flocks, frequently alongside their Bay-winged Cowbird hosts and domestic livestock. As obligate brood parasites, they do not build nests or provide parental care. Females covertly lay their eggs in host nests, ...
The Screaming Cowbird is a resident species distributed across a significant portion of temperate and subtropical South America. Its primary breeding and year-round range encompasses central and northern Argentina, extending north through Paraguay and Uruguay, and into the southern states of Braz...
Least Concern
- The Screaming Cowbird is perhaps the most specialized brood parasite in the world, almost exclusively targeting the Bay-winged Cowbird (Agelaioides badius) as its host. - Its eggs are nearly identical in color and pattern to those of its Bay-winged Cowbird host, making them incredibly difficult...