A boa constrictor found on Big Pine Key this week is raising eyebrows among those tracking non-native big snakes in the Florida Keys, but residents shouldn't worry about an Everglades-sized problem just yet, wildlife officials said.
The 6-foot snake was removed from the west side of the island Wednesday, but it appears it either was an escaped or released pet, according to Robert Reed, a U.S. Geological Survey scientist who is part of a research team in Key Largo that focuses on big snakes and their encroachment into Monroe County.
The snake was not a Burmese python, the non-native big snake species that is wreaking havoc in Everglades National Park just north of the Upper Keys, Reed said. Pythons have been reported in the Upper Keys, but don't appear to have made it much farther south -- yet, Reed said.
Scientists are wondering, but are not yet alarmed, about an assortment of boa constrictors that have been popping up in Big Pine Key and No Name Key in the past five years or so. Still, researchers want people to report any big snakes they see, given the number of sightings, Reed said.
"Boa constrictors are showing up with alarming regularity around Big Pine Key," Reed said. "I don't think we have any evidence of an established boa constrictor population. We would be seeing reproducing females and juveniles born recently. Once we start seeing those, that suggests something is going on we don't want. These are strong snakes that are very good at getting out of cages, and this case is a good reminder for people to keep their eyes open."
There have been cases of people elsewhere releasing big snakes on purpose simply because they like them, but whether or not this is happening in the Big Pine Key area remains to be seen, Reed said.
Either way, it seems unlikely that the boa constrictors were feeding on the protected Key deer, as the snakes need to grow quite large to take down an animal that size, but Reed didn't rule it out, either.
"These snakes are pretty good at taking advantage of whatever's there," Reed said. "Small ones eat mice, rats; and as they get bigger, they eat larger and larger prey items. Birds, mammals and iguanas are all prey."
More of a concern are species like the endangered Lower Keys marsh rabbit.
"Boa constrictors may not be wiping out Keys marsh rabbits on their own, but they could be one more stresser on an already stressed population already in decline," Reed said. "We don't want them to be the straw that breaks the camel's back."
Big snakes don't have to eat that often and may not eat for months, so necropsies often do not provide evidence of what the snakes were eating, Reed said. Sightings were more common a few years ago, said U.S. Fish & Wildlife Service Florida Keys Refuge Manager Anne Morkill.
"But we're still getting a couple a year," Morkill said. "It's rare that the snake is still there when we get there. What happens more often is we'll get a report and then we can't find them."
There was a 95-pound, 10-foot boa constrictor removed from No Name Key in 2009, Reed said.
Morkill and Reed urge residents to report any sightings by calling 888-483-4681 or 888-IVE-GOT-1.
"That big boa we took out in 2009 we conclusively matched from a picture taken in 2006," Reed said. "So this animal was out there for several years and obviously doing really well. It was eating something and we sure would like to know what that was."