image

Science

Alligator vs shark: study reveals top predators are eating each other in America

Researchers caught more than 500 alligators over 10 years and found remains of sharks up to four feet long in some of their stomachs

PUBLISHED : Wednesday, 18 October, 2017, 6:23pm
UPDATED : Wednesday, 18 October, 2017, 6:30pm

American alligators are frequently seen ambling around golf courses in Florida as players warily compete their rounds. But new research suggests the reptiles partake in a far more outlandish habit when away from the greens – eating sharks.

US researchers have documented instances of alligators preying upon small sharks along the Atlantic and Gulf coasts. A study, published in the journal Southeastern Naturalist, claimed it was the first scientific study of the largely unseen struggle between the two feared predators.

“The frequency of one predator eating the other is really about size dynamic,” said James Nifong, a researcher at Kansas State University.

“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.”

US environmental group to sue government over status of Pacific walrus as an endangered species

The findings bring into question how important sharks and rays are to the alligator diet
James Nifong

Nifong and his colleagues spent nearly 10 years studying alligators along the Florida and Georgia coasts, typically using lamps at night to view their nocturnal hunting activities. More than 500 alligators were caught and had their stomachs pumped to see what they had consumed.

Alligators typically eat fish, crustaceans and snails, but Nifong’s research found evidence they had consumed three species of shark and a type of stingray. The sharks measured three to four feet.

By looking at the historical record, Nifong noted evidence of alligators tangling with sharks as far back as the 1870s – but the observations were limited to an island off the Georgia coast. One such encounter saw a group of sharks attack alligators feeding on fish.

The new research found that shark-eating alligators are in fact found along the Atlantic coast of Georgia and Florida, around to Florida’s Gulf coast.

‘It wasn’t crazy’: biologist takes electric eel shocks in the name of science

Although sharks prefer saltwater and alligators are freshwater dwelling, Nifong said sharks and rays can swim into freshwater and GPS tracking of alligators showed that the animals are opportunistic enough to take advantage.

“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.”

More research is required to show whether alligator attacks on sharks are increasing.

Encounters between the two top predators, however, may be influenced by coastal development that has pushed alligators out of their estuarine habitats – threatening their populations.

“The findings bring into question how important sharks and rays are to the alligator diet as well as the fatality of some the juvenile sharks when we think about population management of endangered species,” Nifong said.