MIAMI At least 431 manatees have died in Florida waters so far this year, exceeding in less than three months the total for any full calendar year on record, authorities said on Tuesday.
A preliminary report from the Florida Fish and Wildlife Conservation Commission attributed most of the deaths of the marine mammals to "cold stress syndrome" during this year's unusually harsh winter.
With 431 manatee deaths, Florida has already surpassed the record-high number of 429 fatalities that occurred in state waters last year. That was the most for any year since record-keeping began in 1974.
The West Indian manatee, related to the African and Amazon species and to the dugong of Australia, grows to 10 feet and more than 1,000 pounds (450 kg). It has no natural enemies, but is vulnerable to prolonged exposure to water temperatures below 68 F (20 C) degrees.
State scientists counted a record high number of 5,067 manatees living in Florida waters earlier this year, topping the previous high of 3,807 recorded in 2009.
(Reporting by Tom Brown; Editing by Sandra Maler)