NAPLES (CBS4) – Another one of Florida’s most endangered cats, a Florida panther, was struck and killed by a tractor-trailer along I-75 in Collier County. Authorities say the accident happened Wednesday in the eastbound lanes near mile marker 98.

The Florida Fish and Wildlife Conservation Commission says this is the third panther death of 2011. The other two deaths occurred in Hendry County. Twenty-three cats were killed in 2010. The remains are being held in Naples until it can be transported to the wildlife agency’s research lab in Gainesville.

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Florida panthers have been listed as an endangered species since 1967. An estimated 100 to 150 remain in the state. They are found in swamplands such as Everglades National Park and Big Cypress National Preserve.

The FWC asks drivers to obey posted speed limits and watch for panthers crossing roads at dusk and later.

Panthers tend to be more active during the hours between dusk and dawn, when most automobile strikes occur.

FWC biologists say panthers often make a sudden dash as a car approaches, limiting the ability to avoid an accident, especially when drivers are traveling at higher speeds.

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To help protect the large cats from increasing traffic threats, the FWC, along with sheriff’s deputies and the Florida Highway Patrol, actively enforce panther speed zones in Lee and Collier counties. Panther speed zones are well-marked, with speed limits reduced at night to 45 mph.

Collier County has four panther speed zones: two on State Road 29 and two on U.S. 41, including a zone that runs through Collier-Seminole State Park. In Lee County, there are three panther speed zones.

Motorists who violate panther speed zones often receive fines exceeding $200 for their first offense. There is a mandatory court appearance for any violation of more than 29 mph over the posted limit.

For more information on the Florida panther, go to  To report dead or injured panthers, call the Wildlife Alert Hotline at 888-404-3922.

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