Bolivian Blackbird Oreopsar bolivianus Scientific name definitions

The Bolivian Blackbird is endemic to Bolivia, in fact it is the only genus endemic to that country. While it may look like various all-black icterids, molecular data strongly suggests that its closest relative is the Bay-winged Cowbird (Agelaioides badius). Their vocalizations also suggest a close relationship. Bolivian Blackbirds are found in various inter-montane dry valleys in the interior of Bolivia. In fact it likes habitats with a preponderance of tall columnar cacti and very unusually it nests in crevices on cliffs! It is the only obligate cliff-nesting icterid. It is usually found in small flocks, and these break up to a certain extent during the breeding season. However, there is evidence that there may be helpers at the nest, similar to that of the Bay-winged Cowbird. In parts of Bolivia, this species can be found with the Bay-winged Cowbird where their behavior can be rather similar. Although entirely black, with dark eyes, in flight this species shows brownish wings and in some situations this paler, browner wing coloration can really stand out. Although much of the habitat this restricted range blackbird likes has been heavily impacted, it appears to adapt well to agricultural development as long as nesting areas are not touched, and some cacti and taller shrubs or trees remain in the habitat.

Male 23 cm, average 73·5 g; female average 66·2 g. Medium-sized, all-dark icterid , bill with decurved culmen . Plumage is almost entirely black , with little iridescence; flight-feathers sepia-brown, conspicuous in flight; iris brown; bill grey; legs dusky grey. Differs from Molothrus bonarien­sis in larger size and lack of obvious iridescence; from Gnorimopsar chopi in brownish wings. Sexes similar. Juvenile resembles adult, but with brownish tinge on upperwing-coverts and underparts.

C Bolivia, mostly in Cochabamba, Potosí and Chuquisaca, probably also in nearby parts of La Paz and Oruro.

Dry intermontane valleys (six or more months of dry season). Often in open xeric woodland (with Prosopis, Acacia, Schinus, arborescent cacti, etc.) and scrub; commonly seen in irrigated and cultivated land in such sites, even around rural buildings. Usually not far from cliffs used for nesting. At 1400–3500 m.

Song a simple sequence of short “chip” notes interspersed with “chip-it” notes, simpler, less harmonious and higher-pitched than that of Gnorimopsar chopi. Calls include “chu-pee” as contact and “pee” flight call, reminiscent of those of both Agelaioides badius and Gnorimopsar chopi; also a dry rattle.