Crocodiles can climb trees. And they do it well, too: Some of the toothy reptiles have been spotted as high as 32 feet up a tree.
That’s not somewhere a normally aquatic crocodile ends up by accident.
Once considered a characteristic of extinct crocodilians, this proclivity for scampering up trees is common in today’s crocodiles, a team of scientists reports in Herpetology Notes [pdf]. That’s surprising, because crocodiles don’t really have the anatomic adaptations needed to easily grip tree branches and scale tree trunks in the way that sloths or monkeys do. But various sightings suggested that the reptiles, and their alligator friends, were somehow managing to become tree-borne.
To determine just how frequently crocodiles climb into trees, the team looked in several places. The first was published scientific literature — all three references, one of which, dating back to 1972, described how baby crocodiles could “climb into bushes, up trees and even hang on reeds like chameleons.”
The second? Anecdotal reports from around the world describing crocodiles and alligators in trees. Turns out, the behavior has been seen quite a bit by people living in crocodile-rich areas. Among other places, arboreal crocodilians have been spotted in the mangrove swamps near Tulum, Mexico; in Mississippi (photo, above); in Colombia, where juveniles can be found 30 feet up; and along the Nile.
Next, the scientists set out to collect a few observations of their own. In Australia, they saw crocodiles in trees — and spotted one individual attempting to scale a chain-link fence. In the Everglades and Central America, many crocodiles were spotted basking on the concealed lower branches of mangrove trees. At some of these sites, the only way the reptiles could have reached their resting spot was by climbing up the tree trunk itself. And in Africa, Nile crocodiles and their relatives were seen just as frequently in trees as were some birds. In many instances, these reptiles were lying on tree limbs that were nowhere near the water. One was spotted on a log 13 feet above the water and 16 feet from the riverbank. “To reach this site the crocodile would have had to scale a [13-foot] completely vertical bank and then walk amongst the branches to reach the end of the tree,” the authors reported.
Overall, the team found crocodiles in trees, day and night, pretty much everywhere they looked. They suggest the behavior exists as a means for regulating body temperature and surveying the environment. But the crocodiles are skittish — most promptly fell off their logs or dove into the water as observers approached.