(CNN) In just the first eight months of the year, the number of manatee deaths in Florida has surpassed the total for all of 2017, according to a report by Public Employees for Environmental Responsibility (PEER).

Some 540 manatees died through Aug. 12 compared with 538 manatee deaths in 2017, PEER said citing data from the Florida Fish & Wildlife Commission. Experts blame the spike on cold weather and toxic red tide algae.

If manatee deaths continue at this rate for the rest of the year, 10% of the manatee population will perish, the PEER report said.

"Florida's manatees have no defense against this ecological disaster," PEER Executive Director Jeff Ruch said in a statement. Ruch said red tide poisons both manatees and their food supply. "Florida's steadily declining water quality is a death warrant for the manatee."

There have been more red tide-related manatee deaths this year than in any year of the past decade -- with the exception of 2013, PEER said. Red tide is the known or suspected cause of 97 manatee deaths this year. In 2013, 277 red tide-related manatee deaths were recorded, pushing the total number of deaths to 803 that year.

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