Chestnut-headed oropendola

The male is 35 cm (14 in) long and weighs 225 g (7.9 oz); the smaller female is 28 cm (11 in) long and weighs 125 g (4.4 oz). The wings are very long. Adult males are mainly black with a chestnut head and rump and a tail which is bright yellow apart from two dark central feathers. The iris is blue and the long bill is whitish. Females are similar, but smaller and duller than males. Young birds are duller than adults and have brown eyes