Photographs of distinctively scarred manatees (Trichechus manatus) were taken at aggregation sites throughout Florida and assembled into a catalog for identifying individuals. Resightings of known manatees in different years or at different locations enabled us to document site fidelity and long‐distance movements. Of the 891 individuals included in the catalog as of August 1986, 470 (53%) were resighted at least once. We documented 219 cases of seasonal returns to specific aggregation sites and 98 instances of movements between areas. Movements in excess of 820 km were documented for individuals on the east coast of Florida. Rapid movements south during early winter, as well as northerly spring movements, verify a seasonal migration pattern for many individuals along Florida's east coast. The wide‐ranging migratory habits of manatees in Florida must be considered if meaningful management strategies are to be developed and implemented.
Sixty-four aerial surveys were flown during cold, winter weather between December 1982 and February 1772 to provide an index of trends in abundance of the Florida manatee (Trichechus manatis latirostris) around five Florida Power t;c Light Company (FPL) plants. The survevs documented high winter use of warm-water discharges at four of the plants (eanaveral, Riviera. Port Everglades, and Fort Myers). The total number of manatees sighted at the five primary plants surveyed during a single survey tanged from 6 to 765 manatees (f = 330 ? 45 manatees per survey): thus, up to 4 1% of the total Florida manatee minimum population of 1.850 animals may be found on cold days at FPL plants. The number of calves sighted at the plants during winter has decreased; similarly, for three consecutive years (winter 1989-1970 through winter 1771-19921, the percentage of the manatees that are calves sighted at the plants has decreased. Although data from the surveys of FPL plants do not necessarily reflect what may be happening with manatees located elsewhere in Florida, a possible reduction in calf numbers, coupled with increasing numbers of dead calves being documented by scientists involved in manatee carcass salvage work, is cause for concern in this slow-reproducing, endangered species.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.