The opossum, nicknamed the Prairie Dog, met a gruesome fate last fall in Key Largo, Florida. But thanks to a rare accessory called a tracking collar that leads the scientist to its killer, it can be said that it got its revenge.
Prairie dogs are being explored by scientists through the Key Largo Nature Reserve, a 53-mile-long island off the southern coast of Florida, as part of ongoing research to understand how these mammals migrate. was one of dozens of opossums and raccoons equipped with tracking collars. But researchers also hope that tracking potential prey could lead to the invasive Burmese python. The Burmese python is relatively new to Key Largo, but has been wreaking havoc in mainland Florida’s Everglades for decades with its voracious appetite for mammals.
“The secret, underlying potential application is [this initiative] It could lead to the capture of pythons,” says Michael Cove, conservation ecologist on the project and research curator of mammalology at the North Carolina Museum of Natural Science. “It was a kind of hope, not the hope that these animals would be eaten, but the hope that if they were, it would lead to their capture and removal.”
For Cove, the project grew out of his commitment to conserving two species of rodents found only in Key Largo. Key Largo Woodratt (Neotoma Floridana Small) and Key Largo cottonmouth (Peromyscus gossypinus allapaticola). Young and smaller pythons feed on both creatures, both of which are considered endangered. And rodents are intriguing beyond endangered status. The Key Largo Woodrats build huge nests out of dirt and sticks that can hold animals for generations. “Basically, they’re creating these giant compost heaps in the forest, and many other species use those compost heaps as habitats and foraging grounds.” Cove says.
Cove and his colleagues wonder whether raccoons and opossums feed on Key Largo woodrats and Key Largo cottonmouths, or whether these rodents prey on the island’s limited resources (such as native fruit and nesting grounds). I wanted to find out if it was competing with If so, raccoons and opossums may have stepped in from human residents who put out litter and cat food that didn’t appeal to native rodents. may have reduced stress on rodents. Scientists hoped that by tracking the opossum and the raccoon, they would be able to identify which one was the culprit.
Researchers can’t complain when a collared opossum or raccoon happens to be a beacon pointing to a giant, invasive snake. Thus, in November 2022, invasive species engineer Joe Reddinger and three of his colleagues discovered that a prairie dog opossum had eaten a 12-foot, 62-pound snake that he had pulled from the ground. I noticed that there is
The hours of extracting the snake were the culmination of weeks spent tracking the signals emanating from the prairie dog’s collar after it warned that it had stopped moving. A lengthy tracking process was required due to the ability to hide in bedrock. “It takes a lot of patience. It’s incredibly difficult to find,” Rödinger says of the snake.
“They’re camouflaged really well. They blend in wonderfully with the fallen leaves,” he added, noting that he nearly stepped on multiple pythons in his work. You may be right on top of and don’t know.”
But after Redinger and his colleagues hauled the snake out of its hiding place and euthanized it, there was one less Burmese python in Key Largo’s delicate ecosystem, and because it was a mature female, about 60 fewer python eggs. became.
The first reliable reports of Burmese pythons on Key Largo were made in the mid-2000s, but the exact number of snakes that have settled on the island in the last two decades is unknown. “Population estimates are some of the most important missing pieces as long as we are successful in curbing the Burmese python invasion,” said Jacqueline Guzy, a population ecologist with the US Geological Survey. .Florida python review in email to Scientific American“So far, there are no reliable estimates of python populations, including Key Largo.”
Cove says more snakes are observed on Key Largo each year, but the fact that there are still many mammals on the island means the situation isn’t all that dire. “We are still in the relatively early stages of the invasion front,” he says. “There is still potential for management before it is too late.”
In fact, a more advanced python invasion would have left so few mammals that the collar project would not have been possible. Cove compared the situation to what is happening in the Everglades. Snakes ruled the Everglades for decades, eating not only opossums and raccoons, but also bobcats, rabbits and foxes. But in Key Largo, medium-sized mammals are still in abundance, so they’re collared.
Kelly Crandall, a master’s degree student in forestry at Southern Illinois University who collects mammalian data as part of her master’s project, learned that raccoons and opossums can be infected by feral cats on the island. I was particularly interested in studying toxoplasmosis, a disease that population.
Scientists know that toxoplasmosis can make some species of animals more reckless. So, although Crandall didn’t think pythons would have a chance to eat collared animals, he wondered if infection would make it more likely that the snake’s lunch would be studied.
“There have been a lot of questions about whether or not pythons eat research animals, and whether they can,” says Crandall. She says she is probably only 2% to 5% of the total raccoon and opossum population on the island that the team has collared. “I didn’t know if they would come across a big snake,” says Crandall. “We didn’t know how many very large snakes that would kill raccoons and opossums were in the landscape, and we were also concerned that collars would deter them.”
But prairie dogs aren’t the only collared mammals to encounter pythons. In January, a warning from a raccoon collar finally allowed his team members to remove his second large snake. In February, his second collar on the opossum set off a warning, but project personnel tracked it down and found a few stray hairs in a pile of snake poop, not a snake. rice field. Scientists believe the python that got caught by the opossum must have been about 16 feet long.
With three confirmed encounters and two snakes outside the ecosystem, wildlife officials want to expand the project and use the technology as a means of catching pythons. , says Cove. But even for Key Largo, collaring his prey is just one of a series of tactics experts use to keep pythons at bay.
“Python researchers generally subscribe to the same philosophy: there is no foolproof way to rid the world of pythons,” says USGS ecologist Guzy. “Each has its limitations, so the more tools you have at your disposal, the better.”
And the removal of all pythons is also important to Crandall, who loses hard-earned research animals when pythons attack. ,” she says. “It feels great.”
