More than 400 manatees have been killed in Florida waters so far this year.

More than 400 manatees have been killed in Florida waters so far this year. (Red Huber, Orlando Sentinel)

Manatee deaths in Florida appear to be on a record pace and could reduce the gentle sea creatures' overall population to dangerous levels, according to a U.S. Fish and Wildlife Service report released on Thursday.

In just the first three months of this year, 409 manatees died in Florida waters, compared with 115 in the same period last year. The total number of deaths last year in Florida was 392.

"I don't know that we've ever reached such a high number of manatee deaths this early in the year," said Jaclyn Lopez, staff attorney for the Center for Biological Diversity, an environmental non-profit organization based in St. Petersburg. "The overall message is that we need to be doing more to protect or our Florida manatee populations."

Most of the deaths were the result of red tide on the state's west coast, cold water temperatures and undetermined causes. Only 20 deaths were blamed on human activities, such as boat strikes or getting tangled in fishing nets.


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In South Florida, eight manatees this year have died in Broward, three in Palm Beach County and three in Miami-Dade. Of those 14, three were due to human activity.

Florida Fish and Wildlife Conservation Commission officers are constantly patrolling state waterways, searching for speeding boaters, said Katie Purcell, spokeswoman for the agency's law enforcement division.

The goal is to protect the manatees by enforcing slower speeds "as well just educating people on where the manatee zones are and what they should be looking for," she said.

Lopez would like to see the wildlife agency and others step up enforcement of speed zones because boat strikes account for most human-induced manatee deaths. She also would like to see more signs warning of manatees zones, and better identification of areas were manatees gravitate during southern migrations.

After departing colder habitats in northern Florida and Georgia, manatees gradually arrive in South Florida's warm waters in November and December. Because of their migration, watercraft speed restrictions go into effect on canals, rivers and the Intracoastal Waterway from mid-November through the end of March.

New boating restrictions in Broward County add about 22 minutes to a boat ride down the Intracoastal. In Palm Beach County, however, budget cuts have resulted in fewer law enforcement boats on the water to catch speed-zone violators.

Manatees are an endangered species. As such, they can afford to lose only about 14 per year to human activity if they are to sustain their population, Lopez said.

Yet, on average, for the past five years, people have killed 94 manatees per year, or more than six times the number to keep the overall population healthy, she said.

"To have almost 100 deaths per year due to human causes is unacceptable," she said.

kkaye@tribune.com or 954-572-2085