Florida manatee numbers up, survey finds

The Florida manatee population has reached 2,353 this year, according to marine scientists

March 17, 1999
Web posted at: 6:20 p.m. EST (2320 GMT)

A Florida manatee study completed March 6 has recorded the second highest number of manatees since 1991 -- 2,353 statewide.

The highest count ever made was in 1996 when 2,639 manatees were recorded across the state.

The study -- the third one completed this winter -- was conducted by the Department of Environmental Protection Florida Marine Research Institute. Twenty-nine researchers from nine agencies counted manatees from both the ground and by flying over coastal waters.

"The ability to do three counts in one winter increases the statistical reliability of the population trend indicators that are partially based on these counts," said Dr. Bruce Ackerman, DEP biologist and coordinator of the statewide surveys.

Researchers counted 1,397 manatees from the Suwannee River to the Everglades. This was the highest count ever recorded for the west coast, according to FMRI scientists. The east coast count, from southern Georgia to Biscayne Bay, was only 956 manatees.

"Though the statewide count this year was relatively high, we are concerned about the low counts on the east coast of Florida," said Dr. James Powell, manatee research administrator for DEP's FMRI. "The total statewide number may be misleading since manatees in some regions may be doing well and experiencing an increase in population while manatee populations in other areas may have higher mortality that reduces their numbers."

"Manatee counts can vary by hundreds within a single winter season and between years. This suggests statewide synoptic surveys as a research tool for assessing manatee population needs to be improved," said Powell. "We are planning research for next year that will refine our survey approach to better track actual manatee population trends. This approach could include more frequent on-ground counts and aerial counts at fewer sites."

The leading causes of death among Florida manatees are human-related, according to Florida officials. These include collisions with boat propellers, entanglement in float and fishing lines and ingestion of foreign objects, such as trash thrown from boats.

FMRI officials suggest that Florida citizens help ensure manatee conservation by following safe boating practices, obeying speed restrictions, staying clear of manatee refuges and avoiding damage to seagrass beds.

For more information, contact Leigh Demateis, FMRI, (727)896-8626.

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