Use of tools in the animal kingdom usually conjures up images of chimpanzees and other great apes using tools to find food. It has recently been discovered that some crocodilian species also use tools to get food, though in a slightly different capacity. This research comes from Vladimir Dinets of the University of Tennessee and was published in Ethology, Ecology & Evolution.
Crocodiles and alligators have become noted for their intelligence in recent years. They have large brains relative to their body size; larger than any other reptile. They are also able to learn the habits of potential prey, so be sure not to make a routine out of visiting crocodilian-infested waters at the same point in the day. They have social relationships and are able to bond with one another through playtime. Even orphaned babies can be adopted by other adults. Now it turns out that they can even use tools to help get a meal.
The tools are not held in their mouths or claws, but balanced on their heads while they remain submerged in the water. A few sticks are placed on the head and snout, disguising the reptile from prey. To waterfowl such as egrets and herons, this looks like a log with some free sticks to use for nest making. When the bird tries to retrieve the sticks, the “log” springs to life and gets a great snack. More interestingly, this type of behavior doesn’t happen all year long. Using sticks to bait the birds is confined to the spring months when these birds are mating and nesting and are more in the market for sticks.
While the sticks do help the reptiles blend in better with their surroundings, this process is not as much camouflage as it is bait. Because crocs and alligators are using a foreign object with an intended purpose, this qualifies as actual tool use. The research team believes that crocodilian animals might be hoarding the sticks that are in high demand in order to lure the birds over to them. Crocodilians have been suspected of baiting birds before using fish remnants, but this study represents the first well-documented reports of such deliberate behavior.