US alligators are eating sharks, and here's the proof

The circle of life in the wild can be a tricky one and knowing the pecking order is never straight forward.

One might think sharks are the king of the water but recent research has found US alligators like nothing better than to snack on sharks and stingrays.

The reptiles have been found grabbing the animals as they swim by in estuaries in Florida and Georgia.

Wildlife biologist at the Kennedy Space Centre Russell Lowers and James Nifong of Kansas State University have detailed the new findings for the first time.

"Before this there have only been a few observations from an island off the Georgia coast," Nifong said in a statement from Kansas State.

"But the new findings document the occurrence of these interactions from the Atlantic coast of Georgia around the Florida peninsula to the Gulf Coast and Florida panhandle."

The findings are hard to comprehend given the fact that alligators are freshwater dwellers and sharks live in saltwater.

"Alligators seek out fresh water in high-salinity environments," Nifong said.

"When it rains really hard, they can actually sip fresh water off the surface of the salt water. That can prolong the time they can stay in a saltwater environment."

Nifong added that it is not uncommon for sharks and rays to swim into non-saline water where alligators can't pass up a good meal.

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An alligator's diet typically consists of crustaceans, snails and fish, but because alligators are opportunistic predators, Nifong said sharks may end up on the menu.

Nifong and his colleagues pumped the stomachs of more than 500 live alligators to learn more about their diet.

“There's not a ton of people out there stomach-pumping very large alligators,” he told the The Washington Post.

“They're actually very difficult to stomach-pump and retrieve prey items. It's very tough to be certain that you got everything out of there.”

They also equipped alligators with GPS transmitters to watch their movements and found the creatures often travel to estuaries containing both fresh and salt water.

"However, the frequency of one predator eating the other is really about size dynamic," Nifong said.

"If a small shark swims by an alligator and the alligator feels like it can take the shark down, it will, but we also reviewed some old stories about larger sharks eating smaller alligators."