When did the panther cross the river?
No one knows for sure, but traces of a female Florida panther have been found north of the Caloosahatchee River for the first time since 1973, the same year the Endangered Species Act was approved.
The Caloosahatchee River has been a breeding barrier for more than four decades, but the big cats seem poised to retake another chunk of their historic hunting range.
Male Florida panthers have been documented as far as Georgia in recent years, but females have stayed in South Florida. Having a female population north of the river is part of the species recovery goals for the state and federal agencies responsible for protecting endangered and threatened species.
"We've occasionally had reports of females north of the river, but we've never been able to verify these," said Kipp Frohlich, deputy director of habitat and species conservation for the Florida Fish and Wildlife Conservation Commission.
Biologists haven't actually seen the female, but tracks have been verified by panther biologists and dogs used to find collared panthers have indicated to their owners that the cat is female.
A photo of what was thought to be female was taken north of the river in 2015, and scientists captured more photos of what they thought was a female panther in that same area of Charlotte County.
"It's strong evidence," Frohlich said. "We've seen the tracks and have made casts of the tracks, and our houndsmen also indicates that it's a female."
Biologists found tracks from the panther in question earlier this month.
“This appears to be the milestone we’ve hoped for. We have been working with landowners to secure wildlife corridors to help panthers travel from south Florida, cross the river and reach this important panther habitat,” said Larry Williams, state ecological services supervisor for the U.S. Fish and Wildlife Service, said in an email. “While we do not know if this female used these tracts of land, we do know that securing lands that facilitate the natural expansion of the panther population are critical to achieving full recovery.”
Expanding the breeding population north to Central Florida is listed as the second management goal identified in the FWS Florida panther recovery plan.
The casts FWC biologists made of the tracks were too small to be from a male panther and too large to be a bobcat. The agency says there are between 100 and 180 panthers in Florida, mostly living south of the river and Lake Okeechobee.
Conservation groups were happy to hear about the adventurous female.
"What is hoped under the recovery plans is that females would move north the Caloosahatchee (river) on their own and begin to establish a breeding population in Central Florida," said Nancy Payton, with the Florida Wildlife Federation. "and it appears that is happening."
The panther population has exploded over the past 20 years or so, after a group of female Texas cougars was introduced into the population to restore genetic diversity in the panther.
There must be two separate populations of 240 or more panthers in order to lower the panther's status from endangered to threatened.
Another sign of a growing population is the increased number of documented deaths. Twenty-eight big cats have been killed by cars this year, with total recorded deaths being 36, according to FWC records.
Records were set for both overall deaths (41) and road kills (30) in 2015. The rate of kitten births exceeds the documented death rates as the population is growing due to females having litters each year.
Payton said she wouldn't be surprised if FWC found more females in Charlotte County and beyond.
"Females tend to set up their range next to their mothers range, so if there's one, there may be another — or more," Payton said.
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The (Fort Myers) News-Press