New research shows crocodiles frequently make their way up trees to bask in the sun and keep an eye on their environment.
You might think of crocodiles as being at home in the water — but it turns out these toothy reptiles are also quite comfortable scaling trees.
A new study documents the surprisingly common tree-climbing behavior in crocodiles and alligators. Even without any special anatomic adaptations for gripping branches, crocodiles often make their way up trees, sometimes going as high as the crown.
Vladimir Dinets, a research assistant professor at the University of Tennessee, Knoxville, and lead author on the paper, wasn’t out looking for crocodiles in trees. In the course of his research on the natural behaviors of crocodilians, he and his colleagues noticed a number of the animals in trees and became curious. Everywhere the researchers observed crocodiles and alligators — in Australia, North America, and Africa — they found them climbing trees.
The researchers also combed the scientific literature and collected anecdotal observations from around the world. Although there were only three scientific reports of tree-climbing crocodiles, the behavior has been seen quite a bit by people living near crocodile habitat.
“People who work or live around crocodiles knew about this behavior. It’s really common, but nobody outside the crocodile research community was aware of it,” says Dinets.
“There’s no reason to think this behavior is new,” says Dinets. “In fact, there is some evidence that some extinct crocodilians were even more adapted to climb trees than the species alive today.”
The researchers believe tree-climbing is driven by two factors: thermoregulation and surveillance of the environment. Crocodiles took to the trees most frequently in areas where there were few places to bask on the ground, suggesting that the behavior is a means for regulating body temperature. And the reptiles were quick to fall or jump into the water if the researchers approached them. This skittish response implies they climb to gain a better perspective of potential threats and prey.
Although crocodilians date back to the time of the dinosaurs, they’re still surprising us. In 2013, Dinets and his colleagues reported that alligators and crocodiles use sticks as lures to attract birds looking for nesting material. The reptiles lie in the water beneath bird colonies with sticks resting on their noses, ready to snap when a bird gets too close.
Christopher Gomez, an alligator hunting guide with Alligator Hunt LA, says that although he’s never seen an alligator up a tree, the behavior doesn’t surprise him. “They’re really fast and maneuverable on land,” he says. “And knowing that they’re strong enough to take down large prey and drag them underwater, I’d say they’re strong enough to climb trees.”
So the next time you’re in crocodile country, remember to keep your eyes peeled not just on the water, but in the trees.