In 1958 the state of Florida put the Florida panther (Puma concolor coryi) on its endangered species list. But in 1967 the state's panther populations dwindled to less than 50. The US government then put the cat on its federal endangered species list. The panther population continued to shrink. Until scientists decided to introduce another panther to the mix to strengthen the population, which was too small and genetically compromised. Will panthers be able to survive the encroachment of highways, houses and businesses within their territory? Will people be able to accommodate this wildcat roaming among their housing developments, interstate highways, homes, and shopping malls?
Shrinking Territory
When humans encroached on panther territory, the dangers were enumerable. Shrinking territory led to panther deaths, smaller populations, inbreeding, genetic defects and higher mortality. Scientists and politicians took unprecedented measures to protect the cats. To stop them from being killed on highways, fences and underpasses were built for them. The federal government reclaimed 25,000 acres for wildlife preservation, and the state reclaimed about 70,000 acres. But one male panther can require hundreds of square miles of territory, so even 100,000 acres of newly acquired panther territory failed to cease mortality rates.
Zoos
Over the years a numerous plans to revive the panthers proved futile. All were highly controversial, like when scientists suggested simply removing the panthers from the wild and breeding them in zoos. The group "Fund For Animals", claimed it was futile to raise panthers in captivity without assuring that they had adequate habitat. Some environmentalists disagreed and thought captivity was the only way to save the animals. State and federal agencies thought the captivity programs were too severe. An article in the St. Petersburg Times from March 21, 1993; "Cat Fight", documented some of the politics surrounding the scheme. To and fro they argued, year after year while various conservation efforts sputtered and failed.
Subspecies
Given the futility of the problem it seemed just as ridiculous when scientists introduced a plan to try to introduce other animals of a different subspecies to the region. Biologists conducted their first trial run in 1988, bringing cougars from Texas cougars (Puma concolor stanleyana) to different reserves in Florida to see if they would survive.
The cougars barely made it. Some were killed, others wandered onto farms looking for food, and many had to be removed and brought back to Texas. The biologists persisted. In 1993 they brought in more cougars, according to an article in the New York Times (May 11, 1993); "Cougars enlisted in Effort to Save the Florida Panther". This time they imported younger animals, and introduced them to their new habitat after hunting season, so that they could establish themselves before being displaced by dogs.
Scientists brought in females instead of males because they required less habitat. Throughout 1993 and 1994 according to various news sources, the animals were brought from Texas, radio labeled, tracked, and promptly removed if they became problematic. Another article in the NYT (November 2, 1999) reported that the introduced panthers had produced quite a few "hybrid" cubs; "Texas Rescue Squad Comes to Aid of Florida Panther".
Throughout the years, as they were shot, killed by traffic, or removed after homeowners complained, the program at times seemed be destined for failure, either logistical failure or by intense lobbying efforts against the experiment. Scientists expressed disapproval. The panthers were doomed without more territory said some, while others insisted that native populations were stable and/or growing, that territory had shrunk and could only support a small population, or that the panthers were "specialized", and would never populate a wider territory. More complained that biodiversity efforts and budget were being wasted on the program or that the hybrid offspring would lose the endangered status of the purebreds.
Will it Work?
However it seems like the program is actually working. Pimm et al recently publicized a research paper forthcoming in Animal Conservation (2006); "The Genetic Rescue of the Florida Panther", which challenges some of the opposing beliefs. The authors show that hybrid panthers have successfully moved into new territory. They acknowledge that their counts of species seem almost unbelievable -- they count 3 times more hybrids surviving then purebreds, but explain that hybrid cubs appear to be heartier than the indigenous populations. Females hybrids survive longer then purebred panthers but males don't. While their study offers support for this type of population survival intervention, the authors don't jump to conclusions about the success of such genetic introductions. Rather they acknowledge that it's a complicated issue and that arguments on both sides are "logically compelling". According to the Duke University press release
"Pimm was himself skeptical about the success of such a rescue attempt in his 1991 book, "The Balance of Nature? Ecological issues in the conservation of species and communities." He acknowledged in his interview and in the new paper that 'I was wrong.'"
As the re-population efforts progress, another long held idea brought into question is the notion of a separate "Florida panther" species. In the popular press, most accounts now refer to both subspecies as "panthers" rather then drawing a distinction between the Florida cats as "panthers", and the Texas cats as "cougars". The original distinction was based on dubious calculation about geographical territory that led to people to believe in the rather special species of Florida panthers, as opposed to the "common" cougars. Although there are genetic distinctions between the cats, scientists like Dr. Stephen O'Brien showed that historically, the cougars range extended throughout America, and that while humans in certain areas claimed to have distinct populations of "cougars", or "panthers", or "jaguar", or "puma", all were subspecies that shared descendants.
[More on the Florida Panther:] PloS Biology Has an article on conservation efforts of the Panther here
