The synoptic survey is a count of manatees over a broad area conducted by researchers who fly over areas where they expect to see the most animals. While not a precise population count, the survey provides researchers with a snapshot of manatee distribution and a minimum number of manatees in Florida waters.
The Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute reported a preliminary count of 3,807 manatees statewide.
A team of 21 observers from nine organizations counted 2,153 manatees on Florida's East Coast and 1,654 on the West Coast of the state.
This year's count exceeded the previous high count from 2001 by more than 500 of the endangered animals. In both years, survey conditions were favorable for aerial observations. No survey was conducted in 2008 due to unfavorable weather conditions.
A swimmer and a wild manatee inthe Crystal River National Wildlife Refuge in Florida
Although synoptic results are not population estimates and should not be used to assess trends, the FWC is encouraged by this year's high count.
Survey results are consistent with population models that show the manatee population appears to be increasing in Northwest Florida, along the Atlantic Coast and on the upper St. Johns River.
Researchers have been conducting synoptic surveys since 1991, weather permitting, to meet the state's requirement for an annual count of manatees in Florida waters. Weather and manatee behavior affect synoptic survey counts. The best conditions for the synoptic survey occur during the coldest months of the year, when manatees gather at warm water sites.
"Several cold fronts passed through Florida over a short time period, causing a large number of manatees to move to warm-water sites," said Fish and Wildlife Research Institute biologist Holly Edwards. "Good weather conditions allowed the manatees to be easily seen and counted, contributing to this year's high count."
Researchers at the institute are testing new survey methods that will provide a population estimate for Florida manatees as outlined in the Fish and Wildlife Conservation Commission's manatee management plan. The adjustments to the survey will help achieve more accurate results and reduce dependency on the weather.
Still, 2008 manatee mortality figures released by the commission earlier this month also stood at record highs, particularly for juvenile animals.
Watercraft strikes and newborn deaths were the two most common causes of manatee deaths in 2008, and the numbers for both were above the five-year average, biologists said.
In December, four conservation organizations concerned about the fate of the endangered Florida manatee formally petitioned the U.S. Fish and Wildlife Service to revise the manatee's federal "critical habitat" designations.
Since the original critical habitat designations were made more than 30 years ago, the groups say, much has been learned about manatee biology and habitat needs, and designations of critical habitat should reflect the best available science.
The groups submitting the petition are Save the Manatee Club, the Wildlife Advocacy Project, the Center for Biological Diversity, and Defenders of Wildlife.
Manatees are found in shallow, slow-moving rivers, estuaries, saltwater bays, canals and coastal areas.
Manatees are a migratory species. Within the United States, manatees are concentrated in Florida in the winter, but they can be found in summer as far west as Texas and, rarely, as far north as Virginia.
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