Study Shows that Alligators Eat Sharks and Stingrays

Amazingly, a recent study has shown that alligators eat sharks and stingrays. We all know that alligators will gobble up just about anything that their jaws can reach. The man who led the study, James Nifong, who is an ecologist from at Kansas State University, said this is very surprising as alligators have long been considered to be freshwater predators.

The thing is that when Nifong began asking alligator gurus as to whether they had ever heard of these reptiles eating elasmobranchs—the official name of the group which includes sharks, and stingrays—many of them assumed that this was a joke he was playing on them.

After some persistence Nifong confirmed four instances where an alligator consumed a nurse shark, a lemon shark, a bonnethead shark, as well as a stingray.

He also managed to uncover a few historical accounts showing where sharks had preyed on American alligators, which suggests that these two carnivores go at each other much more often than previously thought.

As Nifong stated in his findings that were published in the Southeastern Naturalist:

“Both are known for their extreme eating habits, and both are highly opportunistic predators. So, when presented with a potential opportunity to feed, they are not likely to pass it up.”

Characterizing the Battles between Sharks and Alligators

The observation of shark and gator confrontations is actually pretty rare for a few reasons. To begin with, both animals can be quite difficult to observe and follow in their natural coastal habitats. Additionally, alligators usually consume sharks that are considerably smaller than the shark on Jaws. Thus, these sharks would probably look like just another fish to a typically onlooker.

These days, alligator researchers use a technique of evaluating stomach contents from live alligators. The method is described as a cross between the Heimlich maneuver and a standard stomach pump. The question is should there not be more evidence shark matters in alligator guts?

Those who pick through gator vomit say probably not. They claim that anything the alligators eat is transformed to mush very quickly in their tummies. So the contents are pretty much indistinguishable.

Ancient Enemies

Elsewhere in the world, there are several observations of crocodilians—a group that includes alligators, crocodiles, and caimans—duking it out with elasmobranchs.

In Australia, people have witnessed saltwater crocodiles going into the surf to hunt bull sharks. Similarly, a study published earlier this year found that more than half of the freshwater sawfish sampled in Western Australia sported scars inflicted by freshwater crocodiles.

And in South Africa, one Nile crocodile was found with the remains of two unidentified shark species in its belly. (Read “How Nile Crocodiles Are Bigger and Badder Than Alligators.”)

There are even some crocodilian fossils that show bite marks from ancient sharks, hinting that these predators have been enemies since the Late Cretaceous period.

Wild and Crazy Place

Perhaps most interesting are the several accounts Nifong uncovered of sharks attacking large groups of alligators.

In the most bizarre instance, in 1877, hundreds of American alligators congregated in an inlet near Jupiter, Florida, attracted by fish trapped by the high tide. Hundreds of sharks, sensing potential prey, followed. In the days after the battle, beaches as far as 80 miles away were littered with carcasses of both species, according to The Fishing Gazette, a sports magazine at the time.

While these historical accounts were “definitely embellished”—probably to exaggerate the number and size of the animals involved—“the fact remains these were definitely observations of alligator-elasmobranch interactions,” Nifong says.

Rosenblatt agrees: “Gators are known to congregate in large groups occasionally to feed on abundant prey, and sharks are known to do the same thing, so it’s certainly possible that large-scale interactions would take place between the two.”

He adds that both gator and shark populations are generally smaller than they once were, which could explain why such massive gatherings are rare today.

“Nature is a wild and crazy place.”