Aided by a string of cold snaps, state scientists counted a record number of manatees in Florida waters this year.
The annual aerial count, conducted two weeks ago, recorded 3,807 manatees, topping the previous high in 2001 by more than 500 animals, according to a report released Wednesday by the Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute.
Wildlife managers cautioned that the aerial counts don't mean the population has suddenly boomed or the endangered mammal is no longer at risk. They amount to a snapshot, a minimum number that can vary wildly according to weather.
"Good weather conditions allowed the manatees to be easily seen and counted, contributing to this year's high count," said FWRI biologist Holly Edwards.
This year's count was conducted in conditions similar to ones that produced the previous record of 3,300 in 2001 _ a clear day following cold snaps that corral the temperature-sensitive sea cows at power plants and other warm-water havens, where it is easier to spot animals from small planes. That count was preceded and followed by surveys recording 1,000-plus fewer animals. Still, the state wildlife agency labeled the results encouraging, saying the results reflected other population models that suggest numbers are increasing in Northwest Florida, along the Atlantic Coast and on the upper St. Johns River. There is more concern and less confidence about the numbers in Southwest Florida and the Everglades, where dark waters make the animals difficult to see and count.
The annual counts, despite their uncertainty, have become fodder in the long and bitter debate over whether the population of mammals is rebounding or still in serious trouble.
Environmental groups, led by the Save the Manatee Club, have battled for years with developers, marine industries and boating groups over that question. They have also fought over state and federal regulations on everything from slowing boats - which account for about a quarter of manatee deaths each year - to curbing dock and marina construction in Southwest Florida.
In 2007, Florida's wildlife commission postponed knocking the manatee down a notch and ordered another population study - but only after Gov. Charlie Crist echoed environmentalists' concerns about the uncertainty of population assessments.
Scientists have developed a number of good measures of the health of regional populations - primarily, the survival rates of adults and calves that can be identified by signature prop scars.
The FWC is also testing a new annual survey method that would use statistical calculations and computer modeling the agency said improve accuracy and reduce the effects of weather.
(c) 2009, The Miami Herald.
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