Warmer weather and law enforcement efforts may have helped reduce 2012 manatee deaths to 392 in Florida, the lowest number in four years, according to the Florida Fish and Wildlife Conservation Commission.
Freezing temperatures threaten manatees because they are not naturally insulated enough to survive temperatures below 68 degrees. But encounters with boats and humans also take their toll.
Since 2008, Florida has recorded 2,377 manatee deaths. The highest sea cow death count was 766 during an unseasonably cold 2010.
Of those 2,377 deaths, 439 were attributed to boats and other watercraft and 31 were caused by other human-related encounters, according to FWC.
"When the cold became less of a factor, we still saw about a quarter of the manatee deaths due to human-related causes, including watercraft," said FWC spokesman Kevin Baxter. About the 2012 figures where 81 of the 392 deaths were attributed to watercraft and nine to other human-related causes.
"Manatees are an endangered species, and they face a number of threats," Baxter said.
Besides watercraft threats, manatees get trapped and drown. They also succumb to prenatal illnesses and to "red tide" algae blooms.
"Water-control structures like a dam or a floodgate can trap manatees, and they'll drown or get crushed," said Baxter, who pointed out the 11 structure-related deaths in 2012 were the highest since 1991.
In Florida, it is a misdemeanor to "intentionally or negligently annoy, molest, harass, or disturb any manatee."
FWC officials said they have taken efforts to better educate the public on how to protect these gentle mammals that can grow to 13 feet in length and weigh up to 1,300 pounds.
Major Jack Daugherty, a FWC Boating and Waterways officer, said FWC officers identify waterways that have presented problems, and work with the public to boat more safely in those areas.
The agency "encourages boaters to stay in marked channels, and to obey speed zones," Baxter said. "Boaters can look out for ripples in the water, which are a footprint of the manatees."
When necessary, law enforcement officials take more severe measures.
In October, a St. Petersburg woman was arrested by the Pinellas County Sheriff's Office and charged with violating the Florida Manatee Sanctuary Act after she was photographed riding on the back of a manatee.
The woman, who was released on $1,500 bail and faced a maximum fine of $500 and six months in jail, told authorities she did not know the mammals were a protected species.