The Key Largo Woodrat's Wild Ride
Upon spotting a Key Largo woodrat, even an educated local from the Conch Republic might shrug, thinking of prolifically-reproducing mice and rats. Woodrats, however, are a wholly different genus, facing the threat of extinction. Yet mice and woodrats are connected, too, because The Mouse is trying to save the endangered woodrat.
The quiet conservation efforts of Walt Disney World scientists have made substantial and award-winning progress. Fueled primarily by corporate goodwill traced back to Walt Disney's vision, Mickey's friends are reintroducing his not-so-charismatic cousin to a U.S. Fish & Wildlife Service refuge in the Florida Keys. Last year, the effort bore fruit – or rather, woodrats – when a captive bred female woodrat, fondly named "Tweak," successfully gave birth to a pup after almost 60 days in the wild.
"Not only do the animals raised at Disney's Animal Kingdom have the skills to survive in the wild, they are breeding and producing offspring." says Dr. Anne Savage, Disney's Senior Conservation Biologist. "Tweak was the first captive born female to give birth in the wild. It was an important event in the history of the Key Largo woodrat recovery program."
Success, however, was not immediate. Instead, as is often the case with great accomplishments, failure came first. After months of captive breeding in a backstage holding facility, scientists plucked twelve rats from their enclosures and moved them to Crocodile Lake National Wildlife Refuge. Obstacles abounded.
Photo of a perched Key Largo Woodrat, by Clay DeGayner, available online at FavorFloridaKeys.com
In the dry coastal hammocks of Key Largo, the woodrat survives without any freshwater at all. Water comes from its diet: from the wild coffee that spots the understory, or from the fruits of the distinctively-spotted trunks of the mastic tree. The gumbo limbo tree, sometimes called the "tourist tree" by Floridians due to its peeling reddish bark, dominates the canopy.
Trash mounds, however, mar that natural beauty. Along one dirt trail is the rusted metal frame and rotted upholstery of an old automobile. Along another dirt road is the 20 foot tall debris mound of the old "Ready Room" and Nike missile site used during the Cuban Missile Crisis. Dozens of mounds of concrete can be found in scattered locations, now overgrown by 30 years of vegetation. The current state of the area makes it hard to imagine how the lands could ever have been planned to become Port Bougainville, a development project that would have included 15 hotels and over 2000 condos. But the old adage applies: one person's trash is another person's treasure. And for the Key Largo woodrats, trash is treasure. Every fallen tree and every pile of concrete and coral is an opportunity. Every clump of gathered twigs is a sign.
"I know nothing about anything, and barely graduated kindergarten," laughs Ralph DeGayner, a gray-stubble wearing Michigan retiree and Florida snowbird, "but I do know something about woodrats." He and his clean shaven brother Clay DeGayner each donate over 1000 hours annually as volunteers to the U.S. Fish and Wildlife Service. They even think like woodrats.
"They look for a roof," says Ralph, pointing to a mound of trash he declared to be a "natural" nest. Natural, that is, when compared with one he built for the reintroduced species. "They need a flat rock above their sheltered nest."
"They need multiple access and escape routes too," adds Clay. "And the giveaway is the stickpile." The challenge for the woodrats is to find the sticks without getting eaten.
Clay DeGayner (left), and his brother Ralph DeGayner (right), have volunteered thousands of hours to benefit the Key Largo woodrat. Among their contributions is this simple tool for tracking the presence of feral cats by finding the predator's footprints in the sand. Photo by Keith Rizzardi.
For regional land managers, the Key largo woodrat presents yet another variable in an already complex system. As a species listed for protection under the Endangered Species Act, the woodrat creates significant regulatory headaches. Land management decisions that might be simple elsewhere, like a trash removal plan, or a coastal spoil mound relocation, trigger a requirement to consult with federal scientists. Through that "consultation" process, biologists try to determine whether the proposed action will jeopardize the continued existence of the entire species or adversely modify the woodrat’s critical habitat. With wood rat populations estimated at 300 or so in 2007, and as low as 134 in 2010, the risk of species extinction is real.
Sadly, the tiny native woodrat captures none of the public attention given to other wildlife in the Everglades and Florida Keys. The underfunded National Wildlife Refuge where it lives is closed to the public. Worse yet, “restricted access” signs do not stop the predators. Woodrats frequently become prey for the much-beloved feral cats in the area, necessitating difficult conversations with the wealthy neighbors who live in the nearby Ocean Reef Club. In fact, federal wildlife managers continue to seek public input on plans to trap feral cats in the region. But until such a plan is fully implemented, the bowls of water left outside by well-meaning (but ill-informed) people will save the lives of feral cats but serve as death sentences for the cats' unlucky prey.
Then again, death – or more precisely, extinction – was exactly what “Python Pete” wanted when he sent an untraced e-mail to federal officials, declaring his plan to introduce exotic Burmese pythons to the Everglades. According to locals, even though state and federal refuge lands were acquired through eminent domain more than 30 years ago, hard feelings still exist decades later, leading the devious Pete to adopt his plan for woodrat destruction. Regardless of whether the story of Python Pete is legend or not, the invasive pythons (and local raccoons) present a real threat, and woodrats are routinely found in the stomachs of autopsied predators.
Poor Ralph. Named after his volunteering friend, Ralph the woodrat got eaten first. In fact, the entire first group of reintroductions quickly suffered Ralph’s fate. Twelve rats were released, and within two weeks, all twelve disappeared -- exactly as conservationists expected. Darren Wostenberg, a contractor from Genesis Laboratory, was one of the prognosticators. He wandered the woods for weeks, with a satellite device strapped to his back and an old-fashioned antenna in his hands. Recording beeps amidst the static, he was present at the beginning when the rats were released, he tracked where they went, and he discovered where they met their ends.
"You don't put your best stock out the first time around," explained Wostenberg. Savage agreed, chiming in. "This is a scientific process,” she added. “You learn what works, and what doesn't, and then put out the more virile animals.”
Photo of Darren Wostenberg searching for radio telemetry signals from a pile of rocks that sheltered "Remy" and other reintroduced Key Largo woodrats. Photo by Keith Rizzardi.
Aided by the knowledge gained by the first group of woodrats, the Disney biologists brought out the A-team. "A" as in Aggressive. Theory and anecdotal evidence suggested that the more the woodrats bit and lunged in their cages, the more likely it seemed that the animal possessed the independence and dominance needed to survive in the the wild. Still, conservation science ruled the selection process, and conservation geneticists from the U.S. Geological Service ultimately decided on which woodrats to reintroduce to their native habitat.
The journey for these woodrats begins in the backlots of Disney’s Animal Kingdom, where a simply constructed gated compound provides the breeding grounds and enclosures for the reintroduced animals. In interconnected cages, complete with wheels and tubes like a pet hamster’s “Habitrail” system, these woodrats sleep, forage and exercise. Nearby, Disney biologists grow native foods to feed the woodrats, simulating their natural diet and preparing them for their upcoming journey.
Creative low-tech thinking makes that journey less traumatic. Rather than moving just the woodrat, Disney biologists move its home. The nest boxes at Animal Kingdom are placed into a transport box, and loaded into a truck for the trip to Key Largo. Upon arrival, the woodrat's transported nest fits into a larger nest structure, built from sticks, rocks and debris by volunteers (including the DeGayners) and surrounded by wire mesh. After an acclimation period, the conservation biologists remove the gates, mesh and protective barriers, and the woodrats, fitted with radio telemetry collars, can explore their new, and much larger, environment.
Aided by the work of such dedicated conservation scientists and volunteers, the future looks brighter for the Key Largo woodrat. In 2010, two feisty females named Tweak and Patty found mates and successfully bred after being reintroduced. Remy, a clever male named after the character in the Pixar film, Ratatouille, showed resilence. He moved from nest to nest, and even escaped a cat, as indicated by an open wound on his back foot, a broken toe, and numerous lacerations discovered by field biologists who trapped him. Remy found a girlfriend, too.
Months later, Remy lost his collar. No one knows what happened to him. Perhaps he suffered Ralph’s fate, or perhaps not. But either way, Remy the woodrat, and his friend Mickey Mouse, are giving an entire species new hopes and dreams.
BY KEITH W. RIZZARDI
Celebrating Earth Day, April 22, 2011
Photo of Anne Savage, Ph.D., Senior Conservation Biologist, Disney's Animal Programs, next to a protected nest structure awaiting its new resident.
For more information, read Anne Savage's blog entry about the Key Largo woodrat (with a great photo, too). And also visit THE RAT RACE: Protecting the Key Largo Woodrat By Christina Alligood, PhD, Anne Savage, PhD, and Andre Daneault available online. For reproduction rights, please contact firstname.lastname@example.org