Last year's 829 Florida manatee deaths—a figure that doesn't include December, UPI notes—is more than double the number that died in 2012, according to one conservation group. Another organization, the Florida Fish and Wildlife Research Institute, put the 2013 figure at 803. Either way, it's the first time the number has broken 800 since record-keeping began in the 1970s, the AP reports. The numbers mean roughly 16% of the Florida manatee population died last year; some 176 were breeding-age females, an expert tells the Tampa Bay Times. Manatees remain an endangered species.
Experts point to toxic red tides, prompted by algal blooms, as a major factor; they left 276 manatees dead last year, according to the Public Employees for Environmental Responsibility. That's almost as many as died from red tides in the past eight years total, and the group's director calls it "the product of systemic environmental irresponsibility." Anti-water pollution rules and enforcement "have completely broken down in the state of Florida," he notes. Another big killer last year was a still-undiagnosed disease in the manatee-populated Indian River Lagoon; the illness killed 115. Some died so quickly, they still had food in their mouths; click for more on the baffling die-off. (Read more manatees stories.)