Chestnut-headed Oropendola

The Chestnut-headed Oropendola, Psarocolius wagleri, is a striking bird of the New World tropics, named to honor Johann Georg Wagler, the founder of its genus. Males are notably larger than females, with the former reaching a length of 35 cm and a weight of 225 g, while the latter measure 28 cm and weigh 125 g. The species is adorned with a black plumage contrasted by a chestnut-colored head and rump, and a vivid yellow tail save for two central dark feathers. The bird's blue iris and pale bill add to its distinctive appearance.

Identification Tips

Adult males are predominantly black with a chestnut head and rump, and a bright yellow tail with dark central feathers. The long bill is whitish, and the iris is a striking blue. Females share the same coloration but are smaller and less vibrant. Juveniles are more subdued in color and possess brown eyes. There is a potential subspecies, P. w. ridgwayi, found south of Honduras and Nicaragua, though its distinction is debated.

Habitat

The Chestnut-headed Oropendola favors the forest canopy, edges, and old plantations. It thrives in the Caribbean coastal lowlands and is often seen in the verdant canopies of southern Mexico to central Costa Rica, as well as in Panama, Colombia, and northeastern Ecuador.

Distribution

This bird is a resident breeder in its range, which extends from southern Mexico to central Costa Rica, encompassing both slopes of southern Costa Rica and Panama, and the Pacific lowlands of Colombia and Ecuador. It is typically found below 1,000 meters above sea level but has been recorded up to 1,300 meters, as in Colombia's Serranía de las Quinchas.

Behaviour

Often observed in small flocks, the Chestnut-headed Oropendola is a sociable bird. It forages in trees for large insects, fruit, and berries. During the breeding season, it exhibits colonial nesting behavior.

Song & Calls

The male's song is a captivating auditory display, beginning with a gurgle and culminating in a percussive crash, described as "guu-guu-PHRRRRTTT." Both sexes communicate with loud "chek" and "chuk" calls.

Breeding

A colonial nester, the Chestnut-headed Oropendola constructs elaborate hanging nests from fibers and vines, which dangle from high tree branches. A colony may consist of 40-50 females and a mere 4-5 males. Females lay two pale blue eggs adorned with dark markings, which hatch after 17 days and fledge in 30. Nestlings face threats from botflies and brood parasitism by giant cowbirds.

Similar Species

While unique in its appearance, the Chestnut-headed Oropendola may be confused with other oropendola species. However, its chestnut head and rump, along with the yellow tail, distinguish it from its congeners.

Diet and Feeding

The diet of the Chestnut-headed Oropendola includes large insects, fruit, and berries, which it forages for in the treetops.

Conservation status

The IUCN has classified the Chestnut-headed Oropendola as Least Concern, indicating a stable population across its extensive range.