ST. PETERSBURG — In January, state officials announced that 2009 marked a record year for Florida manatee deaths. In 12 months, a total of 429 of them died.
That record has already been broken — with more than nine months left in 2010.
As of March 19, biologists with the state's marine science laboratory in St. Petersburg have documented 431 manatee carcasses in state waters this year.
Most of the deaths, 222, have been attributed to stress from the extremely cold temperatures that blanketed the state earlier this year.
Biologists say the cold temperatures most likely contributed to many of the 108 deaths in their "undetermined" category, which is the label they give to manatees that are too decomposed for them to ascertain a cause of death.
They said it was probably a contributing factor to the 64 deaths that are listed in the "unrecovered" category — in other words, manatee carcasses that were spotted but which biologists were not able to reel in and take to the lab for examination.
"The unprecedented rate of mortality this year is of great concern," said Gil McRae, director of the state's Fish and Wildlife Research Institute. McRae's staff is just beginning to consider the long-term effects for the manatee population.
This year's annual aerial survey counted more manatees in Florida's waterways than had ever been counted before: 5,067. The number of deaths so far equals more than 8 percent of that number, and by year's end the death rate is likely to reach 10 percent.
By this time last year, only 148 manatees had died, 42 of them from cold stress. So far this year, 13 manatee deaths have been attributed to being run over by speeding boats.