(CN) - The Florida panther, recognized as endangered for more than 40 years, needs protected habitat to survive, five environmental groups say in Fort Myers Federal Court. Habitat lost to development and human population growth has cost the big cats 95 percent of their historical range, and threats from climate change increase the threat, the groups say.
Fewer 100 Florida panthers remain in the wild, living in 5 percent of their historical range, according to lead plaintiff Conservancy of Southwest Florida, which has been working in Florida since 1964 and owns property in panther habitat.
The largest cat in the East, the panther used to range from Florida to Tennessee and from the Atlantic Ocean west to Arkansas and Louisiana. The cats need broad expanses to fulfill their hunting, denning and dispersal needs: a single male requires about 250 square miles, while a female needs 150.
Males that leave their mother's den range about 40 miles away on average, to establish their own territory.
For a healthy breeding population of 2,000 adult animals, that would require more than 234,000 square miles of habitat, according to the complaint.
The groups challenge the federal government's denial of three petitions from 2009 asking for designation of critical habitat for the panther, which has been listed as endangered since 1967 under the Endangered Species Act.
The panther's current range includes only about 3,500 square miles in the Everglades National Park, Big Cypress National Preserve and up the Caloosahatchee River.
The Fish and Wildlife Service denied the habitat petitions with no explanation and ignored the science presented in them, the groups say. This includes the fact that highway expansion is responsible for unprecedented panther deaths - 17 road kills, including a cub, for 24 total deaths in 2009.
In addition, climate change poses grave threats, including increased hurricanes and flooding. If the sea level rises by 1 meter, it would swamp 29 percent of existing habitat.
The groups seek remand of the agency's refusal to designate habitat.
In a continuing debate on the taxonomic status of the Florida panther, some scientists say it is genetically too similar to the North American cougar to be its own species. Because the animal is so elusive, no solid estimates exist on how many cougars may be left in the West.
Florida panthers eat wild pigs and white-tailed deer. The cougar is the largest purring cat, but cannot roar; it makes sounds akin to chirping, crying and screaming.
Plaintiffs include the Sierra Club, the Center for Biological Diversity, Public Employees for Environmental Responsibility, and the Council of Civic Associations.
They are represented by a bevy of lawyers, including Eric Huber of the Sierra Club office in Boulder, Colo.
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