During November thru April the Oropendola breeding season is in full swing at La Anita! These birds, which are only found in the tropics, are very comical and make incredible sounds as they flip around tree branches caling to one another. Their nests that are totally unique in the animal world, and play an integral role in a symbiotic relationship that the oropendola maintains with the cow bird during mating season.
The oropendula’s intricate hanging nest is made entirely by the female while the male watches and performs his duties of constant female devotion. The oriopendola is known for its gregarious life in an almost constant party mood singing and playing at all times. The bird is a gymnast and if you are able to watch the birds for a time you will see them not only singing but also gripping the branch with their feet and make a complete summersault around the branch while bellowing out their song. Oropendulas also maintain a unique symbiotic relationship to the cow bird…
During mating season, the cowbird, a small black bird, stays nearby and goes almost totally unnoticed by the oriopendola colony. The cowbird is a “brood parasite:” she enters the oriopendola’s nest and lays her eggs so the oropendula will protect the egg and raise the chick.
The oropendula often cares for the cowbird eggs in order to protect its own young. The oriopendola chicks are blind and have no feathers, making them vulnerable to the parasitic bot fly that inhabits the canopy. Contrarily, the cowbird chick has a thick layer of down that protects it from the bot fly parasite. Additionally, the cowbird eats the bot flies and their larvae therefore protecting the oropendula chicks from this deadly parasite. Without the cowbirds the oriopendola chicks have a much lower chance of survival, so the oriopendolas parents embrace the adopted chick into their family.
So in addition to watching the oropendula’s summersault acrobatics, during your stay at La Anita Rainforest Ranch you can scrutinize the nesting area for the cowbirds hanging around waiting for the right opportunity to gain a stepmother for their chicks.