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Saving the Florida Panther From Extinction

Fewer than 50 Florida panthers are left. But not everyone agrees that we should rush to save them.

By Peter Radetsky
Jul 1, 1992 5:00 AMNov 12, 2019 5:35 AM


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Just after daybreak, mist blankets the cypress swamps. Out there, somewhere in the stillness, is the panther. He might be resting after the night’s kill, or he might be empty-bellied and hungry--but he’s there, one of maybe 50 panthers left in the dwindling wilderness of southern Florida. They are the last of their kind, the only great cats remaining east of the Mississippi. And despite the best human intentions, the animals may be doomed.

"Wait! Wait! Wait!" shrieks Melody Roelke from a swamp buggy lumbering down the muddy track that cuts across this northern corner of Big Cypress National Preserve. She is shouting at David Maehr, the buggy’s driver, to pull up. The brakes aren’t working, he shrugs. He downshifts the monster three-quarter-ton buggy to a halt.

Roelke is already over the side, crouching over some animal tracks by the road. They look pretty fresh, she tells Maehr.

Probably the female we caught here last week, he says, gauging the footprint’s size. The grandma of the one we’re after. Maehr, a 36- year-old biologist with the Florida Game and Fresh Water Fish Commission, has supervised more than a hundred cat captures, and the sight of fresh tracks doesn’t raise his blood pressure. He is as laconic as Roelke is intense. Though the 40-year-old veterinarian joined the panther recovery project nine years ago, this might as well be her first capture. She climbs back on the buggy, flashes a quick smile at two veterinary colleagues on board, and resumes her post as scout above the front axle.

A second swamp buggy pulls up, with the team’s tracker, Roy McBride, at the wheel, and two of Maehr’s colleagues, Walt McCown and Jayde Roof, straddling the back bench.The most important passengers lie quietly in a cage lashed to the buggy’s rear. They are the professors of pantherology, McBride’s hounds Jody and Susie. If all goes well today, the professors will find the panther, flush him out of the bushy vegetation, and corner him in a tree.

The panther, number 44, is a 14-month-old male. A year ago, when number 44 was a kitten, Maehr’s crew treed him, anesthetized him, and fitted him with a radio collar. Through surveillance from the ground and air they’ve been keeping close tabs on him and the 20 other panthers currently wearing collars.

Maehr stands up in the buggy and unfurls a large rectangular radio antenna. As he turns it to the east, the receiver begins chirping like a bird. I’m picking him up, Maehr announces. He’s about a mile east of here. Hope he’ll still be there when we get there. He jerks the buggy into gear. By now, 8:30 A.M., the mist has burned away; the sun gleams above the cypress trees. The buggies slosh through black, swampy muck that oozes to the tops of their tires.

Since the project began 11 years ago, the biologists have monitored a total of 45 animals to create a detailed record of the cats’ lives and family trees--where they roam, how often they mate and with whom, how many kittens they have, how they die. Roelke’s veterinary team, meanwhile, has examined the animals, administered vitamins and vaccines, and taken blood, sperm, and tissue for analysis by laboratories at the National Zoo and the National Cancer Institute outside Washington, D.C. The Florida panther (Felis concolor coryi) is probably the most closely studied wild feline in the world, yet it still may be too late to save the animal.

Two hundred years ago these members of the mountain lion family roamed all the way from Texas across the southeastern states to the Atlantic coast. But by the 1900s many had been shot and killed, considered little more than vermin by the ranchers who appropriated their habitat and by hunters who coveted the deer the panthers preyed upon. (Some states, including Florida, paid bounties for the dead cats.) The rest vanished quietly, displaced by human migration and development; by the late 1960s the cats had completely disappeared from sight.

In 1967 the federal government officially put the panthers on the endangered species list, even though it was far from certain that any survived in the wild. To find out, the World Wildlife Fund called in Roy McBride. He treed the first cat in south Florida in 1973 (the same year the Endangered Species Act was passed, providing funding for plans to bring threatened animals back from the brink of extinction). After two more cats were found, a preliminary survey was done that put the panther population at between 30 and 50. Finally, in 1981, the Florida Game and Fresh Water Fish Commission initiated a recovery plan for the animals, beginning with surveillance by radio telemetry to find out precisely how many panthers there were and where. The following year the panther was declared the state animal of Florida.

In order to gauge how much land to allocate the panthers, the commission set out to learn their habitat requirements--the size of a typical animal’s range, the kind of land it preferred, the territorial scope of its hunting and mating patterns. In addition, Roelke was brought in to provide medical care for the surviving cats. But it soon became worrisomely clear that these measures weren’t enough to ensure the animals’ survival. In 1989 the U.S. Fish and Wildlife Service turned to a consortium of specialists for a prognosis on the panthers’ fate. Data from wildlife biologists, population biologists, geneticists, and reproductive physiologists were plugged into a computer program that predicts the future of animal species.The answer was grim. If nothing was done, the Florida panther would vanish within 25 to 40 years.

By 9:30 the buggies are out of the wet swamp and heading east toward drier land, bouncing over an open expanse of cypress, cabbage palm, and palmetto bushes. This is more typical of panther country, observes Maehr. They like to make their dens in the palmetto. The buggies come to a stop again and Maehr raises the antenna over his head. He’s about a half-mile to the south, awful close. He turns to McBride. Why don’t you go on with the dogs? We’ll stay here. The tracker leashes his hounds and sets off with biologists Roof and McCown; they cross a canal and disappear into the pine and cypress.

For the time being, Florida’s state animal has found a safe haven in protected swamplands like Big Cypress and the Everglades. But the panther isn’t truly a swamp animal, notes Maehr. In fact, they disdain swamps as such. They stay out of them as much as they can. Instead they seek out stretches of higher, drier ground within these areas.

Unfortunately, humans prefer the drier land as well. Some of the best terrain for panthers, for example, lies north of Big Cypress in huge, privately owned cattle ranches. Ironically, ranches seem the least of the panthers’ problems these days; because this land is relatively untended, it still supports the deer, hogs, and raccoons that panthers feed on--and shooting Florida’s state animal is now a federal crime. But land cleared for farming is a different matter. Squash and tomato farms abound in southern Florida. And citrus growers in central Florida have expanded southward since the freeze of 1986, transforming wilderness into hundreds of thousands of acres of orange groves. Housing developments and shopping malls, meanwhile, sprawl inland from the urban centers along Florida’s gulf coast, shrinking panther habitat even further.

In addition to these outside pressures, the panthers’ own genes have begun to work against them. With few opportunities for finding unrelated mates, sons are consorting with mothers, daughters with fathers, sisters with brothers. The first signs of the panthers’ inbreeding were innocuous: a hereditary kink at the end of the cats’ long tails and a cowlick in the fur on their backs. Lately, however, the signs have become more ominous. Most males are born with only one testicle descended into the scrotum, says Roelke. Fifteen years ago only fifteen percent suffered the problem--today almost every male we capture is missing a testicle. And their sperm is horrible. They have greater than ninety percent abnormal sperm. It’s as though they’ve reached a biological impasse. If it gets any worse, they won’t procreate, period.

Inbreeding can encourage other, less obvious harmful mutations as well. Two years ago, says Roelke, a cat died from an atrial septal defect, or a hole in the heart. An identical hole was found in another animal killed by a car in February 1991. We’ve discovered murmurs in every kitten born in 1990 and in thirty percent of the adults we examined last year. Moreover, the lack of genetic diversity that results from inbreeding may make the immune system less effective against viruses and parasites and cause high infant mortality.

The final blow, however, may have nothing to do with the panthers’ genetic health. In 1989 a panther in the Everglades died of mercury poisoning, which destroys brain cells and can be passed from mother to offspring in the womb. Two other cats from the same national park have since died with suspiciously high levels of mercury in their blood. Why mercury contamination has become a problem in south Florida is not known.

I’m much more pessimistic than I used to be, Roelke says. Kinked tails, single testicles, and abnormal sperm haven’t yet stopped the panthers’ reproducing. But they can’t live with holes in their heart. They can’t survive mercury poisoning. We may be further along in this extinction process than we’ve let ourselves believe. The condition of number 44 will provide the latest clue as to whether this species has a future.

At 10:00 sharp, the two-way radio crackles to life. Okay, y’all. It’s McBride’s unmistakable drawl. You can come in with both buggies.

"Got him?" asks Maehr.

"He’s treed now. In a pine tree, no brush underneath."

"Sounds good," Maehr says. He asks Roelke to take over the other buggy, and the two vehicles head off across the canal, over dead trees and low brush, then through an expanse of dry grass into a stand of cabbage palms and pine trees. From off to the right comes a sound no one has heard all morning: barking. Although the dogs aren’t in sight yet, everyone is aware that the reason they’re making such a racket is to keep the panther up the tree.

Then, suddenly, there he is. The tawny cat is standing in the fork of a slash pine no more than 50 yards ahead. His small, high-browed face peers down calmly at the professors, who have launched into an unearthly cacophony of yapping, baying, and squealing 40 feet below. The dogs flushed the cat out of a palmetto thicket, McCown reports. He circled the meadow a couple of times with the dogs after him, then went up the highest tree. Pretty easy capture.

Once a panther is treed, the next task is to bring him safely down. Maehr and his colleagues quickly rig a crash bag under the pine to cushion the animal’s fall: they trap air inside a score of plastic garbage bags, bunch them together under a tarpaulin, and cover the giant air bag with a net. McBride, who doubles as the team’s marksman, readies a dart gun and consults Roelke on the cat’s weight. She hands him a dart filled with what she hopes is the proper dose of anesthetic drugs for the animal’s size.

McBride takes aim. The dart zings into the panther’s right flank. Howling, the cat clambers 15 feet farther up the slash pine. Wearing spikes and a belt, Roof starts up the tree behind him, hoping to lower the groggy cat to the safety net. (It’s not an enviable job. Some years ago a flailing panther sunk its claws into the biologist’s rear end. It hung on until it ripped loose and crashed into the net.) As the anesthesia takes, number 44 begins to lose his grip.

"His butt’s starting to come down," yells Roelke.

"He’s slipping!" barks Maehr, finally excited. He orders his team to hold the net taut over the crash bag.

The panther falls, but only as far as his initial perch. Dazed, the cat clings precariously to the tree fork, his haunches sagging, slowly dragging his body down the trunk. "Can you grab his tail?" shouts Roelke. Roof inches toward the cat and reaches up. But the cat loses its grip and plummets into the net and crash bag, landing with a thunk that almost tears the net from its captors’ hands. All hell breaks loose.

McBride pulls his dogs aside while the researchers run to examine the cat. "Color’s good," Roelke says, checking the pink of the animal’s gums. Breathing’s fine. The vets lift the panther in their arms and carry him to a makeshift hospital set up under the trees. They have hung intravenous tubing from the branches, prepared oxygen and drugs in case of emergency, and laid out syringes, surgical instruments, vials, and swabs on a canvas sheet. Roelke gently deposits the animal in the middle. "He’s just a little guy," she notes.

The team hobbles the cat, front paws to back, and weighs him on a hand-held scale, as you would a fish. Seventy-seven pounds. He is a little guy. A full-grown male can weigh upwards of 150 pounds.

There’s a gash on his lip, Roelke adds. He’s been fighting.

"Probably a hog," Maehr says.

The panther lies still, eyes open but seeing nothing, his tongue hanging out. Roelke feels under the animal’s tail. Just one testicle, she says.

Tubes are inserted to drip saline solution into the cat’s bloodstream to keep him hydrated and to take his blood for a variety of tests--to analyze DNA, to screen for antibodies and viral genetic material indicating infectious diseases (a third of the cats are infected with feline immunodeficiency virus, or FIV, the cat version of the virus that causes AIDS). The vets collect feces samples to look for parasites. They pull out a whisker to test for mercury poisoning. They fill a vial with saliva, take swabs of mucus from the cat’s nose, throat, and rectum. (No reason to take semen from this youngster--he probably doesn’t have any sperm yet.) They inject the panther with vitamins and a deworming compound and vaccinate him against rabies and feline distemper and other respiratory diseases. Plucking up a patch of fur, Roelke takes some skin samples to provide further DNA to study the degree of genetic diversity left in these animals.

Something is gnawing at her, though. Just last week the team captured another 14-month-old male. Number 44 is smaller than that male by a good 12 pounds. His ribs and backbone are sharply outlined beneath his fur, his shoulders and legs have less muscle, and it took less anesthetic to bring him down. ‘‘Interesting," Roelke mutters. Was that other one in a better area, or did he have a better mom, or what?

"Might just be a matter of how recent his last big meal was," Maehr muses.

"No, there’s more going on than that. He took almost twenty-five percent less drug than the last one, and it’s not stomach content that does that."

She lowers the stethoscope to the panther’s chest. "Oh, my God. Listen."

"That’s a pronounced murmur," she says. She mimics the swooshing sound made with each heartbeat. "This is pretty nasty."

Yet another cat with a murmur. The sound could indicate a hole in the heart or a leaky valve, but the team isn’t equipped to do diagnostic X-rays or ultrasound in the wild. What is clear is that number 44 has reinforced Roelke’s worst fears concerning the panthers’ future. Less clear is what to do about it.

The answer may lie at White Oak Plantation. Owned by New York paper magnate Howard Gilman, this sylvan refuge at the Florida-Georgia border encompasses, among other things, the southern headquarters of the Gilman Paper Company, numerous guest houses, a studio used by Mikhail Baryshnikov and other dancers, and a 500-acre conservation center for endangered species. It is here that the Florida panther may be forced to make its last stand.

"We’re holding seven cats now," says John Lukas, a 43-year-old biologist and director of the center. Five kittens, Big Guy, and a female, number 21. Both adult cats are accident victims, rescued after being struck by cars. (The female was subsequently found to be infected with FIV and a protozoan parasite.) But the kittens were handpicked by Maehr, Roelke, and their colleagues for just one purpose: to be a living genetic repository. By choosing kittens from unrelated families and mating them in captivity, the researchers hope to mitigate the inbreeding problems that occur in the wild.

Actually, when the U.S. Fish and Wildlife Service originally granted us the permit, it was for six kittens from the wild, observes Lukas. But the fate of the sixth kitten underscores the urgency of the panthers’ plight. The young female turned out to have a defective heart valve, and she was sent to the game commission’s Wildlife Research Laboratory, close to a veterinary school in Gainesville where she can receive emergency treatment. The prognosis for dogs with the problem is one to two years, Lukas adds.

But the remaining kittens, three males and two females, represent the start of an ambitious breeding program. As originally conceived by conservation biologists, the plan was to capture up to six kittens and four adults the first year, and another six kittens and two adults annually for the next five years, with the goal of establishing a colony of 130 panthers and offspring by the year 2000 and a total of 500 cats by 2010. The removal of cats from the wild was planned to disrupt the natural population as little as possible. Only adults that were not reproducing in the wild--for example, young males with no room to establish their own breeding territory--were to be brought to White Oak. As for the kittens, easily half of them die in the swamps before they’re six months old. Given their shrinking habitat, the remaining kittens might fare better with less competition.

Once the panthers can reproduce (at about two years of age), Lukas’s team plans to mate unrelated cats--or as unrelated as they can be in a population of 50 animals--to produce offspring with a good mix of genes. To do so, they’ll have to rely on both the family trees provided by Maehr’s field monitoring and state-of-the-art genetic analysis.

While some panthers will remain in captivity, constituting a sort of living gene bank, others will return to the wild to seed new populations. Besides the Florida swamps, other areas slated to receive panthers include the Osceola National Forest in northeast Florida, the Okefenokee Wildlife Refuge just over the border in Georgia, and the Apalachicola National Forest and the Big Ben Coast in northwest Florida. By dispersing the animals, explains Lukas, you don’t have all your eggs in one basket. If a hurricane or a virus goes through south Florida, you could easily lose all the cats down there.

Some genes may even find their way back to the wild to enrich the gene pool without the cats themselves. Techniques like sperm banking, artificial insemination, and in vitro fertilization make it perfectly possible to mate two animals that would otherwise never get together. For example, frozen semen from a White Oak male could be transported to Big Cypress and used to artificially inseminate an unrelated wild female. The result would be kittens with a genetic mix otherwise impossible to obtain.

At least that’s the plan; in reality, reintroducing panthers to the wild might not be so simple. In 1988 seven radio-collared Texas cougars, feline cousins of the panther, were released north of the Osceola National Forest in what was supposed to be a yearlong dry run for future panther relocations. The outcome was sobering. There was plenty of game for the cougars and, it was thought, plenty of room for them to roam. But within a month one was found floating in the Suwannee River, cause of death unknown. Three wandered beyond the park--one to a nearby exotic-game compound, another to the outskirts of Jacksonville 50 miles away, and one to a goat farm over the Georgia border. Two others were killed by hunters.

By the tenth month of the experiment, all the surviving cougars, including the lone cougar left in the park, had been recaptured and shipped back to Texas. It’s conceivable that straying might be controlled by releasing enough animals inside the park to form stable social structures. But the presence of human hunters in the forest could be more problematic. Circumstantial evidence suggests that the noisy disruption caused by hunters and their dogs contributed to the scattering of the animals. Worse, there appears to be an irresponsible minority of hunters who regard the cats as rivals for deer and other park game, or who want to undermine a program that would bring their activities under closer scrutiny. Obviously, says Lukas, these problems need to be addressed before any panthers are released.

It should come as no surprise that hunters would resist a breeding program committed to returning panthers to the wild. But far greater opposition has arisen from a more unlikely quarter. A well- organized protest has been mounted by Holly Jensen, a local animal rights activist from Gainesville, in partnership with the Fund for Animals, a group with 200,000 members founded by writer Cleveland Amory.

At first glance you wouldn’t expect Jensen, a 39-year-old nurse at a community hospital, to wield such power. Slim, almost preternaturally pale, with straight blond hair that hangs below her shoulders, she looks shy, even meek. She’s nothing of the sort. A self-styled eco-feminist, she’s relentless in her commitment to a variety of environmental causes. For the Earth to survive, we have to make fundamental shifts in our attitudes and behaviors, she says. She backs up her stance by eating a vegetarian diet, carrying a string shopping bag, shunning disposable plastics, using neither air-conditioning nor heat in her home, and joining forces with the Fund for Animals against the panther recovery project.

Early in 1990, as plans were being laid to capture the first animals, this coalition group threatened to sue the U.S. Fish and Wildlife Service if it went ahead without first filing an environmental impact statement. Such a report would have entailed a thorough review of the effects of removing panthers from the Florida ecosystem; it would have required years to complete and much more in-depth study than the simple, federally mandated environmental assessment on which the Fish and Wildlife Service was putting its final touches. In addition, the coalition objected to the capture of adult cats on the grounds that it would disrupt the panthers’ social structure, and it demanded a more detailed study of how and where the panthers would eventually be reintroduced. The messy debate pushed back the completion of the Fish and Wildlife Service’s assessment to November 1990 and delayed permission to take the first kittens to January 1991. Then, in January, just days before the cats were due to be taken into captivity, Jensen and the Fund for Animals made good on their threat to sue, putting the entire project on hold again.

The suit was quickly settled out of court, and a temporary one- year agreement was reached. In lieu of a full environmental impact statement, the Fish and Wildlife Service agreed to supplement its environmental assessment with more detailed plans for managing panther habitat (by identifying suitable parcels of private land, for example, and either buying or protecting them). And no adult cats, it was decided, would be taken during the first year.

Thus, in the early months of 1991, the first six kittens were duly brought to White Oak. But from Roelke’s point of view, precious time had been lost. During the many months of wrangling with Jensen and the Fund for Animals, at least 11 cats had died, taking their genes to the grave with them. In the month between the suit and the settlement alone, one kitten selected for the breeding program was hit by a car, and another litter left its mother before the biologists could get to the animals. The death of the first kitten came as a particularly hard blow--he was the last member of his family’s line.

Jensen, however, sees things quite differently. The point is that there has been all this attention placed on one particular area of recovery, genetics, and captive breeding, she explains. I think it’s because baby kittens are appealing. They provide great pictures for public relations. But what about saving habitat? What about mercury contamination? If this kind of stuff is not addressed, there’s no reason to spend millions of dollars on captive breeding. What you’ll end up with are caged cats and nowhere to put them.

In November 1991, as the initial settlement neared its end, Jensen and the Fund for Animals threatened to reactivate their suit. This time it was averted by the appointment of a third party, the Florida Panther Technical Advisory Council, to oversee the program, and permission to capture both kittens and adults was granted for two more years. The question is, By the time the program is up and running, will it be too late to save the cats? It’s a bone of contention, dividing even those closest to the animals.

I’m ambivalent, says Maehr, whose first concern is learning the natural history of the existing cats left in Florida, not breeding and reintroducing more animals to the wild in the future. I don’t think that our fieldwork has been much affected by the suit. And if we’ve done more self-analyzing and made progress on habitat protection, then maybe that’s a benefit. Right now, I don’t see that the suit hurt us, but it has created additional bureaucratic hassles. It’s been a nagging headache.

But Roelke and conservationists concerned with the panthers’ genetic health and survival are infuriated. I support the need for habitat preservation, says Roelke. That’s fantastic. It’s wonderful. But while they’ve blocked the effort to get these animals bred in captivity, more panthers have died. Now we’re capturing kittens, but who knows if they’ll try to stop us again. If it keeps up, there aren’t going to be any healthy Florida panthers remaining to put in whatever habitat they have.

What is clear is that the opposition to the recovery effort has elevated the fight to save the Florida panther to a different level. Whereas Roelke, Maehr, Lukas, and their colleagues deal with the cats face- to-face, most of the people involved in the lawsuit have never seen a panther. For them the cats represent an ideal encompassing more than the animals themselves. As Jensen put it in a letter to a local newspaper, The panther is to Florida what the tiger is to India or the elephant to Africa. It is symbolic of wild Florida. She and her supporters are using the panther for larger ends, as leverage to maintain and recover the wilderness of their state. But can wild Florida, like vanishing wilderness worldwide, ever be reclaimed? And can the panther survive the fight being waged in its name?

At 11:20, less than an hour after dropping from the pine tree, with the examination complete and a new, larger radio collar around his neck, the Symbol of Wild Florida is starting to wake up. He squirms on the tarpaulin, his limbs twitching.

"Hold on, fella," says Roelke. "Do you have a nest ready, Dave? He needs to be out of the sun because his temperature is elevated."

McBride and McCown lug the cat over to a shady patch under the cabbage palms. Then the crew begins to gather equipment and load it back onto the swamp buggies. All except Maehr. Half-hidden among the palm leaves, he remains behind with the animal as the anesthetic wears off. He sits cross-legged at the sluggish panther’s head, staring at the cat with what can only be called a beatific expression. For half an hour he keeps up his vigil, making sure the cat has no breathing problems and doesn’t try to struggle to its feet while still drugged.

"You looked mighty peaceful in there," says Roelke, when he eventually emerges from the thicket.

"I was until you guys bothered me," replies Maehr. The two start back toward the buggies, leaving behind the palm grove where the young panther is coming to. You do all this work on him, says Roelke, and when it ends you stand back and think, ‘We’re leaving, but this is where he lives. He walks around out here. He finds things to eat out here. Every day.’ Imagine!

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