Awesome Animal Fact - Noisy Oilbirds

Awesome Animal Fact:

Did you know the oilbird is the loudest of all the birds?

You probably wouldn't want to be in a cave when a group of oilbirds fly into the cave to roost. Oilbirds, like bats, use echolocation to find their way around in caves that are totally dark. Bats, however, use a call that is outside the human range of hearing. But oilbirds? Nope, not so much. Oilbird echolocation calls are perfectly audible to humans, and at close range can be up to 100 decibels. Try to imagine a whole swarm of them flying about in a cave all at once. Some colonies include thousands of birds!

Why are oilbirds so loud? Well, as I said, bats use echolocation to navigate in caves and to catch their insect prey outside of caves. Oilbirds, on the other hand, only use echolocation to navigate caves, not to catch their insect prey. This is probably because their echolocation sensitivity is relatively low—they aren't very good at it. In fact, scientists have found that they fly headfirst into plastic discs that are 4 inches (10 cm) in diameter, but they are able to avoid discs that are 8 inches (20 cm) in diameter. If they can't avoid a 4-inch disc, they definitely can't use echolocation to catch insects that are much smaller than 4 inches. Bats, on the other hand, can echolocate the tiniest of flying bugs. So, perhaps oilbirds have such loud calls to make their poor echolocation work at least well enough to avoid smacking into the walls of their cave.

Below are oilbirds clinging to the wall of their roosting cave.

Photo Credits:
- Oilbirds on cave ceiling - DepositPhotos