Is a river crossing good news for Florida panthers?

A Florida panther has made its way across a river, indicating that the endangered species could be expanding its territory.

The animals were initially listed as endangered almost 50 years ago, and today about 200 live in a small section of southern Florida. To ensure their long-term survival, conservationists say the large cats need to move north of the Caloosahatchee River and expand their population there, something that hasn’t happened since the 1970s.

“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,” Larry Williams, state ecological services supervisor for the US Fish and Wildlife Service, said in a release from the Florida Fish and Wildlife Conservation Commission. “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.”

While male cats have been spotted above the river in Charlotte County, conservationists believe they’ve found evidence of the first female panther to do so, determining from photos and paw prints found beyond the river. An automatic camera caught footage of a small panther north of the river last year, but biologists weren’t sure it was female until earlier this month when the tracks appeared.

"When we saw the tracks, we felt confident they were made by a female panther," Darrell Land, leader of the FWC team studying the panthers, said in the release. "We could rule out a male panther because by the time males are old enough to leave their mother, their paws are already bigger than females' paws."

If that female panther begins to mate with a male on the other side, the population occupying the new territory could see a boost, making it more secure and sustainable.

Conservationists say that’s a good sign for the panthers, but not everyone is happy. Residents and local officials say the expansion of the panthers' range poses a threat to local ranchers and communities. The animals require more than 50 square miles of territory each, leading authorities to set aside large slabs of land that others say would be better used for development.

In 2015, the state issued a proposal for the panthers that would involve scaling back their territory north of the river. The measure was adamantly opposed by environmentalists, who worked with officials to amend the plan.  

Still, the surrounding communities feel that initiatives needed to protect the panthers place an undue burden on them and their development.

"Why should Florida carry the whole burden of the panther that once had that broad range, and the expenses that goes along with it? And the cost of development," Paul Carlisle, an administrator from Glades County, told NPR last year. "Yes, development is needed. To be sustainable, we have to have development."