NORTH KEY LARGO -- Keeping the federally-endangered Key Largo woodrat alive and breeding is biologist Jeremy Dixon's goal.
The North Florida native has been hired by the U.S. Fish and Wildlife Service to serve as the full-time manager for the 6,700-acre Crocodile Lake National Wildlife Refuge.
The biggest obstacle in protecting this furry member of the native ecosystem is an invasive species whose presence is widespread in the Florida Keys: the feral cat.
Other than humans, adult feral cats have no natural predators in the Keys. And in a protected habitat that is closed to the public, nothing is stopping them from eating away at the refuge's woodrat population. Cats killed most of the zoo-raised woodrats that were reintroduced a few years ago to Crocodile Lake, causing scientists to admit last year the attempt to help the population rebound had failed.
Woodrats, which are native to Key Largo, once traversed hardwood hammocks from Tavernier to North Key Largo, but now are limited to northern one-third of the island. According to the U.S. Fish and Wildlife Service, the rats feed on and distribute native seeds, berries and nuts and serve as food for native birds and snakes. Scientists say the collapse of the woodrat population would disrupt the native food chain and forest biodiversity.
Dixon graduated from the University of Florida and has previously worked as a bilogist for four years with elk and bison at Wichita Mountains Wildlife Refuge in Oklahoma. Though running his own refuge was a wanted promotion, being closer to family was also attractive.
"I'm a lot closer to home," he said.
Dixon describes his new assignment as a bit of a one-man show but is quick to give thanks to the refuge's small but dedicated volunteer corps. He said he has about 12 regular volunteers and another dozen or so who come to the refuge's cleanup events. A coastal cleanup is scheduled for 9 a.m. Nov. 16. Dixon said volunteers will use kayaks or stay on shore to clean debris that has washed up from Barnes Sound. Like 95 percent of the refuge, this area is normally closed to the public.
Throughout next spring, other projects are planned, including the restructuring of manmade woodrat habitats and upkeep at the refuge's butterfly garden.
The refuge also contains an abandoned Cold War-era Nike missile facility, which Dixon must look after, and he is also tasked with continuing the battle to keep invasive plants out of the refuge. A lack of public access helps reduce the need to fight some invasives, he said.
"This a refuge in its truest form," he said.
Which may be why feral cats like it so much.
An Americorps intern has been assisting Dixon at the refuge's spartan headquarters where he is conducting population research on feral cats using camera footage. Cameras are recording an increased number of cats, Dixon explained, but his study is yet to be finished.
Dixon says people who release or allow unwanted cats to roam may not realize how far they can travel.
"Look at what happens when animals go extinct," Dixon said. "[Woodrats] are on an island and have been introduced to predators."