America’s rarest snake chokes to death on centipede in Key Largo
Who among us has not had eyes bigger than our stomach? While you might target a 28-ounce ribeye, the rim rock crowned snake — possibly the rarest snake in America — has a thing for centipedes. That, apparently, can be a dangerous way to make a living.
Researchers at the Florida Museum of Natural History recently revealed in a study that a rim rock crowned snake discovered in Key Largo died of asphyxiation after choking on a rather girthy Caribbean giant centipede. A hiker strolling in John Pennekamp Coral Reef State Park found the snake on the side of a path with the centipede sticking out of its mouth. Both animals were dead.
The rare snakes typically measure 6 to 9 inches long. This one was 8 inches long, and the centipede measured 3 inches.
It was quite a find for several reasons. Firstly, the Keys are one of the last stands for the tiny rim rock crowned snake, and the snake has not been documented there in nearly four years. The last live snake was seen seven years ago next to the nest of a Key Largo woodrat. Secondly, the snake is so hard to find that we know very little about it. It wasn’t even formally described by scientists until 1966.
“This centipede was the first dietary information ever recorded for this species,” explained study co-author Coleman Sheehy, researcher and collections manager for herpetology at the museum.
‘I was in disbelief ’
When park rangers quickly sent Sheehy photos of two mini-beasts locked in their death pose, he was shocked. “I was in disbelief,” he said. “Any new info about these snakes is really exciting — so little is known about them. My first thought was, we need that specimen now!”
Officials at John Pennekamp Coral Reef State Park jumped into action, putting the snake and centipede on ice and shipping the pair to Sheehy in Gainesville.
Sheehy explained that he was worried about decomposition, but had his fingers crossed. “We’re super lucky we got them in time,” he said.
Once he had them in hand, he and his co-workers used a CT scanner to determine that the snake indeed suffocated. But they also found evidence of the battle. The snake had a wound on its side, and internal damage at the same spot, possibly from a centipede bite.
Sheehy said that both the diminutive snake and the centipede are venomous. He suspects that the centipede most likely died from the snake’s mild venom, but it was so large it blocked the snake’s trachea.
“Most snakes can regurgitate their prey pretty quickly. It’s common for a snake to bite off more than it can chew. But we think this was a different case because the [centipede’s] legs were probably keeping it from being regurgitated. Maybe the snake was weakened by the centipede bite, but certainly the trachea was occluded, so
there was no air flowing.”
Wary of the public’s often sour opinion of snakes, the herpetologist was quick to point out that the rim rock’s venom is extremely weak. “It would never be a danger — ever — to a human. In fact, they don’t even bite in defense, but with it they would be able to subdue and potentially kill their targeted prey.”
He seemed less concerned about the venomous centipede’s reputation. “Good gosh, I would never want to grab one of those,” he said. “They’re much more of a danger to a person than a crowned snake would ever be.” He explained that the dead centipede was actually a juvenile, and that he’d seen adults take down anole lizards. “It would dispatch them quickly and efficiently. … If they bit a person, it would really hurt.”
As for where rim rock crowned snakes fit into the Keys food chain, Sheehy explained that their primary predator would likely be a coral snake. “There’s a large population in Key Largo. They only eat snakes and lizards,” he said.
Why so rare?
Rim rock crowned snakes are found only in South Florida, and the state lists them as threatened. One reason the species is so rare is that its habitat is vanishing. They prefer South Florida’s pine rockland and rockland hammocks — elevated areas with hard limestone soil — much of which has been consumed by farmland, developments and strip malls. Beyond the Everglades, only 2% of the state’s original pine rocklands remain. The Florida Wildlife Commission’s website says that habitat fragmentation can isolate snake populations and put them at risk, particularly with the onset of flooding due to climate change.
The snakes are also difficult to find because they’re fossorial, meaning they stay hidden under rocks, logs and leaves, especially during the day. Sheehy says they may prefer dawn and dusk for hunting or may be nocturnal — no one knows for sure.
There are two other crowned snake species in Florida, the Florida crowned snake, which lives on the Peninsula, and the southeastern crowned snake, which lives from the state’s western Panhandle up to Virginia.
Both of those species are known to have a taste for centipedes as well.
Sheehy said he’s especially pleased that CT scanning allowed them to study the specimen in detail without dissecting it, which would destroy the snake.
“This is an extraordinary opportunity to use new technology to study rare species,” he said. Though these snakes are like rare diamonds of biological information, Sheehy says he can now share the snake
with others.