Even scarier, some crocs can climb trees all the way to the crown of the tree — and the behavior is fairly common.
Vladimir Dinets, a research assistant professor at the University of Tennessee, is the first to thoroughly study this unusual tree-climbing behavior. His study found that at least four crocodilian species, spanning North America, Australia and Africa, were capable of climbing trees: Australian freshwater crocodiles, American crocodiles, Central African slender-snouted crocodiles and Nile crocodiles.
Although crocs usually opt for low-hanging branches above the water, Dinets found that the reptiles were more than capable of climbing vertical trunks. Some were even witnessed climbing to the canopy ... and at night.
"Climbing a steep hill or steep branch is mechanically similar, assuming the branch is wide enough to walk on," wrote Dinets and his colleagues. "Still, the ability to climb vertically is a measure of crocodiles' spectacular agility on land."
Yikes! The good news is that the most prolific tree-climbers were the smaller, younger, more agile crocodiles. In other words, it's unlikely that a man-eater would pounce on you from above.
Researchers theorize that there are at least two reasons for the tree-climbing behavior: thermoregulation and surveillance of habitat. Crocs that climb trees during the day are most likely doing so to sunbathe more effectively, above the shade. But because smaller crocs — the ones that climb most often — are vulnerable to a variety of predators, they probably also climb to get a better vantage point and to watch for threats. In fact, Dinets noticed that several specimens would leap from their perches and plunge into the water at the first sign of approaching danger.
"The most frequent observations of tree-basking were in areas where there were few places to bask on the ground, implying that the individuals needed alternatives for regulating their body temperature," the authors wrote. "Likewise, their wary nature suggests that climbing leads to improved site surveillance of potential threats and prey."
These findings are especially alarming in light of another recent finding, also discovered by Dinets: Crocodilians have been observed using sticks and twigs as lures to hunt for prey. In other words: watch out. Crocodiles are way craftier than they've previously been given credit for.
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