APPEARANCE
The several species of Amazon oropendola (also spelled "oropendula") are similar in appearance, about the
size of a large blackbird (some are smaller), with a pointed conical bill, dark plain plumage (typically
chestnut or brown) on the body and wings and yellow on the tail.
The part of the name "oro-" (= "gold" in Spanish) refers to this bright yellow on the tail, which is a
distinctive identifier for this group of birds. The bill is usually pale yellow. Some species have a dark
green or black bill with a reddish tip.
The oropendola is often heard before it is seen, with a burbling complex musical song.
 Listen to the song of the russet-backed oropendola
(La Selva Lodge, Sucumbios/Napo, Ecuador)
© Don Jones, 12-07-96, courtesy of Xeno Canto
The 13 oropendola species in all are in the same family as blackbirds and orioles, Icteridae —the most
diverse group of birds in the American tropics.
HABITAT AND DISTRIBUTION
Oropendolas generally prefer areas of scattered, open woodland rather than the forest interior. Some
species adapt quite well to human activity, and are common around towns and villages, whereas others have
suffered in settled areas. The commonest species in Amazonia is the russet-backed oropendola
(Psarocolius angustifrons).
FEEDING AND DIET
The oropendola feeds on insects, fruit and berries.
BREEDING
The second part of the oropendola's name ("-pendola") refers to their characteristic pendulum-like nests
(See photo) or perhaps because of their courtship behavior—swinging
around the branch of a tree.
During courtship, the male oropendola perches on a horizontal twig, wrapping his claws around it. He then
swings around the branch, until hanging upside down, with his wings spreads, and his yellow tail feathers
spread out above. He might swing all the way around the branch, or reverse the motion and flipping back to
the top. All the while, he'll be singing his burbling liquid call.
The male display helps to attract females, which usually outnumber them. Among the crested oropendola
(P. decumanus), for example, the colony houses as many as five females for each male. In this case,
the colony has a dominant male, whose territory is surrounded by lesser males, holding lower quality
territory.
The nests of oropendolas are often found in association with wasps' nests. The wasps offer protection for
the oropendola young which are attacked by botflies (the maggots of which burrow into the chicks) by
parasitizing the botflies. These are the main cause of nestling mortality.
Cowbirds, which are brood parasites, eat the botfly larvae and are thus found nesting in the vicinity of
oropendola colonies. (Most birds will not otherwise tolerate a brood parasite, such as a cuckoo, near their
nesting area.)
They are colonial breeders, often polygamous. Their
colony trees are bedecked with multiple nests, numbering dozens in a single isolated tree, looking like
giant fruits. The nests hang from the tip of a branch (truly "out on a limb"!).
The nest is suspended by a few woven strands of palm fiber, which offer minimum purchase for a hungry
predator, such as a snake. In Amazonia, breeding takes place year-round among most species, among others it
may be seasonal. One or two eggs are the norm for these birds, and are usually marked with dark stripes or
spots.
CONSERVATION
Oropendolas prospects are mixed, depending on the species. Some are decidedly rare, becoming more so as
habitat declines due to deforestation and urbanization. Prospects are better for other species that adapt
well to habitat alterations caused by human activities.
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