Florida biologists prove that invasive Burmese pythons swallow deer and alligators whole

The extent to which the Burmese python is capable of wiping out native wildlife populations in South Florida continues to amaze biologists trying to eradicate the invasive species.

Researchers in the region recently demonstrated that Burmese pythons can stretch their jaws wide enough to swallow large prey such as adult deer and alligators, according to a paper published in the journal Reptiles. & Amphibians.

“Knowing the size of prey that predators can eat makes it easier to understand and predict their ecological impact,” the paper says.

A group of biologists came across the nearly 15-foot-long female Burmese python in December 2022 while devouring an adult white-tailed deer, Ian Bartoshek, a wildlife biologist and science coordinator for the Southwest Florida Conservancy in Naples, told ABC News. .

To understand the pythons’ behavior, Bartoszek and his team use radio telemetry, a technique that uses radio signals to track the animals’ movements and behavior. Trackers placed on males help researchers find reproductive females, Bartoszek said.

By the time they arrived at the scene, the python had swallowed about half of the deer, and it took about 30 minutes to eat the other half, Bartoszek said. If the deer were still alive, scientists would have intervened. Instead, they got a front-row seat to the ins and outs of the food chain.

“For us biologists, it was the most intense we’ve ever seen on a mission,” he said. “It was as primal as it gets.”

The female python weighed about 115 pounds, while the deer weighed about 77 pounds, which is 93 percent of the snake’s maximum surface area, the size of its mouth, according to the paper.

According to the Florida Fish and Wildlife Commission, Burmese pythons can consume food equivalent to 100% of their body weight. While deer-tailed deer parts have been found in python autopsies before, this was the first time biologists had seen it in the wild, Bartoszek said.

“In this particular example, it feels like we’ve caught a serial killer in the act,” Bartoszek said.

The large, non-venomous constrictor captures its prey by ambushing it before coiling around it. The snake then squeezes until the animal’s heart stops, Bartoszek said.

In the case they witnessed, the python bit the deer’s neck before circling it, he added.

“When you see their anatomy firsthand, they’re amazingly designed,” Bartoszek said. “Mother Nature has done a very good job with the species.”

Had this python lived, it would likely have “used up” the deer’s food within a week, Bartoszek said. But since they’re hunters by convention, the snake might well have captured its next victim before then, he added.

According to the FWC, a variety of species have been found in the gut contents of Burmese pythons during autopsies, including mammals, birds, reptiles, and federally protected species such as the wood stork and the Key Largo rat.

Burmese pythons are one of the most worrisome invasive species in the region, according to the US Geological Survey (USGS).

According to the USGS, this species, native to Africa, Asia and Australia, has established a breeding population in South Florida through intentional and accidental releases.

According to the USGS, this species is associated with a sharp decline in the mammal population in Everglades National Park. A 2012 study found that since 1997, the raccoon population has declined by 99.3%, the possum population by 98.9%, and the bobcat population by 87.5%. According to the USGS, other mammals have “virtually disappeared” over time, such as jackrabbits, rabbits and foxes. .

“Imagine thousands and thousands of pythons eating their way through the Everglades,” Bartoszek said.

Burmese pythons were added to Florida’s restricted non-native species list in 2021. The state also pays bounty hunters to catch Burmese pythons through the FWC Python Patrol program.

The species, with its efficient reproductive capabilities and voracious appetite, is creating a cascading effect of loss in the Everglades ecosystem and surrounding areas, Bartoszek said.

“We didn’t want to alarm people,” Bartoszek said. “We just want to showcase what our native wildlife is up against in the Everglades ecosystem.”