ST. PETERSBURG — Last year was the worst ever for Florida manatees, with records broken both for the total number of deaths statewide and the number killed by boats.
The state's marine science laboratory announced Wednesday that 429 manatees died — 97 killed by boats. One area where boat-related deaths spiked: the Tampa Bay region.
The number killed by boats is far beyond the limit of 12 a year that a new federal study says would mark the most deaths caused by humans that Florida manatees can tolerate without risking extinction.
"If we don't get this under control, it's going to have a definite impact on the future of the species," warned Pat Rose, executive director of the Save the Manatee Club.
Rose is now urging state officials to install a waterway version of red-light cameras in areas with no-entry, idle and slow zones to persuade boaters to respect the rules that protect manatees.
"This would ultimately be cheaper and safer for both the enforcement agencies and boaters while safer for both boaters and manatees," he said. State officials say they are considering it, but are concerned about the logistics of setting up such a camera system.
The previous record for manatee deaths was set in 2006, when 417 died, 92 of them hit by boats. The previous record for boat deaths was set in 2002, when boats mowed down 95 manatees.
The two big reasons for the increase in deaths this past year were watercraft and cold stress, said Martine Dewit, an associate research scientist with the state's Fish and Wildlife Research Institute in St. Petersburg. Manatees cannot stand cold weather, and that's why they seek refuge in the winter in springs or at power plant outfalls where the water is warmer.
The other big increase was in the number of deaths of young manatees, she said. In the past the deaths of the young have averaged below 100, but last year they surged to 114. Biologists could find no single leading cause for the increase, she said.
Dewit said no one knows the reason for the increase in watercraft deaths, although one possibility is the economy. Because of fuel costs, the state's 1 million boaters may have stayed closer to shore rather than heading for open water, and thus wound up zooming through the places where manatees swim, she said.
Rose agreed, adding that the state's budget crunch has limited how much state wildlife officers were able to enforce boating speed zones, which could lead to further manatee deaths.
Marine Industry of Florida spokesman John Sprague said that was true, noting, "If you repeatedly go out in a boat and you never see a law enforcement officer, you wonder how many violators there are. … It's a problem."
However, he contended that the biggest factor in the rise in manatee deaths is an apparent increase in the number of manatees. The most recent estimate from federal officials is a population of 3,800, which is 600 more than aerial surveys found in 2001.
However, scientists have found the death rate increasing at a faster pace than the population.
Manatees have been a popular Florida icon since the 1960s, featured on everything from license plates to minor league baseball uniforms. They're even the centerpiece of an annual Manatee Festival, which is expected to draw thousands of tourists to Crystal River this weekend.
Settlers and Seminoles considered manatees an excellent food source, but they have been classified as endangered since the first federal endangered species list came out in 1967.
They earned their place on the list not because of their numbers — which at the time were a mystery — but because of the threats to their future from waterfront development and boat collisions. Forty-three years later, experts say those threats remain just as potent.
Under the Marine Mammal Protection Act, the Fish and Wildlife Service is supposed to draw up stock assessments for endangered marine species every year, but the last time the agency wrote an assessment of Florida manatees was 1995. The Center for Biological Diversity sued in 2007, winning a settlement in which the agency agreed to produce a new assessment.
According to that report, released at the end of December, there are an estimated 3,800 manatees in Florida's waterways. In three regions of the state, the population appears to be growing steadily.
But in the area the agency has dubbed the Southwest region, which runs from just north of Tampa Bay south to the Ten Thousand Islands, the population appears to be declining. That region contains nearly half of all manatees in Florida.
In its report, the agency calculated that 12 manatees could be lost each year to human activities — killed by boats, crushed by dam locks, entangled by fishing lines and traps — without endangering the species. But since the report was concerned only with commercial fishing, which had little effect on manatees, the agency found no reason to do anything more to crack down on speeding boaters or deny more permits for dock construction.
Craig Pittman can be reached at (727) 893-8530 or firstname.lastname@example.org.