Chestnut-headed Oropendola (Psarocolius wagleri ridgwayi)

23 January 2009, Rancho Naturalista, Costa Rica I like the powder blue eye color. Males and females are nearly identical, but females lack the crest and males are slightly larger with a more noticeable "casque" on top of the bill. I judge this individual to be a male. Oropendolas are colonial, polygynous New World Blackbirds (Icterids) which build conspicuous, pendant nests. Colonies typically contain 30-40 nests and are occupied mostly by females. This is one of two species of Oropendola commonly seen at Rancho Naturalista. Except for occasional visits to the feeders, we mostly saw them flying high overhead or across the valley. From a distance they look all black save for their conspicuous yellow tail feathers. Generic limits in the Oropendolas has been exceptionally unstable. This species was formerly placed in the monotypic genus Zarhynchus, but it now joins most other Oropendola species in Psarocolius following a 1968 proposal by Blake in the "Peters Check-list of birds of the World." However the bow display of the males of this species is unique and suggests that it may be more distantly related to other species in the group. Two subspecies are recognized with P. w. ridgwayi ranging from Nicaragua south to Ecuador. It is reported to be blacker with a paler brown head and larger bill, compared to the nominate race which occurs north into Mexico. But these distinctions have been questioned and the validity of this race is unclear. Panasonic Lumix LZ5 / Nikon FieldScope 3 / 30X WA hand-held (no adapter)