The Montezuma oropendola, Psarocolius montezuma, is a strikingly dimorphic bird, with males significantly larger than females. Adult males boast a chestnut body contrasted by a blackish head and rump, and a vivid yellow tail save for two central dark feathers. Their facial features include a bare blue cheek patch and a pink wattle, with a brown iris and a long bill that is black at the base and red at the tip. Females are similar in plumage but are smaller with a less prominent wattle. Juveniles appear duller with a paler bill. This species is known for its remarkable sexual size dimorphism, with males being twice the body mass of females.
When identifying the Montezuma oropendola, look for the male's large size, about 50 cm in length, and the bright yellow tail with dark central feathers. Females are notably smaller, measuring 38 cm. The distinctive blue cheek patch, pink wattle, and two-toned bill are key features to observe.
This tropical bird inhabits the forest canopy, edges, and old plantations, preferring the Caribbean coastal lowlands and some Pacific slopes.
The Montezuma oropendola ranges from southeastern Mexico to central Panama, with notable absences in El Salvador and southern Guatemala. It is also found in Nicaragua, Honduras, and parts of Costa Rica.
Males exhibit a female-defence mating system, where the dominant male mates with most females in a colony after an elaborate bowing display. They are known to be aggressive in defending receptive females from other males. Females forage on thinner branches, while males prefer thicker branches, likely due to their size difference.