A combination of cold weather, a decline in seagrass due to development and contaminated waterways have put Florida on pace for its highest number of manatee deaths in a decade, state officials said after a meeting with the Florida Senate

“It’s this combination we have of cold weather, we have a reduction of where manatees can go, and in the places where manatees can go, as a consequence of human development and other activities, we have poor water quality which has resulted in these grass die-offs,” said Jaclyn Lopez, Florida director of the Center for Biological Diversity.

The number of deaths, 539 in the first three months of year, is on track to surpass last year’s total — and soon, according to Florida Fish and Wildlife Conservation Commission manatee mortality data as of March 19.

Last year, the state recorded 637 manatee deaths, and in 2019, there were 607.

The largest number of deaths is in Brevard County, with 179.

Many of those deaths occurred along the Indian River, which is a common warm water gathering place, officials said. The manatees swim away to eat sea grass, which is their main source of food. But they aren’t finding as much, so they return hungry to the warmer water.

“A manatee will choose starvation over freezing to death,” Lopez said. Officials said cold stress has accounted for 41 deaths so far. There were 52 cold-stress deaths among manatees in 2020, officials said.

Patrick Rose, an aquatic biologist and executive director of the Save the Manatee Club, told the SunSentinel that typically manatees would stay in the Banana River or Mosquito Lagoon, in the northern end of the Indian River Lagoon. But the loss of sea grass there is forcing them into other areas.

The southern end of the Indian River Lagoon has suffered from a series of algal blooms and phytoplankton blooms, and the infusion of fresh water and nutrients from Lake Okeechobee has stressed that system and wiped out much of its sea grass, the newspaper reported.

Rose said there are probably more manatee deaths than the state has documented and the causes might not be accurately attributed.

While the state wildlife commission rescues sick and injured manatees, coronavirus pandemic-related personnel shortages and restrictions have meant that nearly 70% of the dead manatees have not had necropsies to determine their causes, Rose said.

“You’re always better off when you have a real scientific understanding of what’s actually happening,” he said.

Last year, FWC reports 29 manatees were injured from watercraft collisions.

For more tips to help protect manatees, click here.

Anyone who encounters an injured or stranded should call the FWC’s wildlife alert hotline at 888-404-FWCC (3922) or by dialing #FWC or *FWC on a cellphone so trained responders can assist