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July 01, 2021

Manatee deaths prompt federal probe

Published on June 09, 2021

Federal wildlife officials are investigating hundreds of Florida manatee deaths during a two-month period earlier this year.

In March, the Florida Fish and Wildlife Conservation Commission informed a Florida Senate committee that 403 manatees had died across Florida between Jan. 1 and Feb. 26. Approximately 85 manatee deaths were reported during the same period in 2020.

The majority of this year’s deaths occurred in the 156-mile-long Indian River Lagoon on Florida’s Atlantic coast. It is believed that manatees may be starving owing to a decline in seagrass, their primary food source, killed off by algal blooms.

A Manatee in the Crystal River, Florida.

“The timing of the deaths is associated with manatees aggregating at warm-water sites, and we believe there’s an interaction between large numbers of manatees at these warm-water sites and food availability,” explained Gil McRae, director of the FWC Fish and Wildlife Research Institute, to the Florida Senate Environment and Natural Resources Committee in March.

McRae’s testimony led Stephanie Murphy, a Florida representative in the U.S. House of Representatives, to request that the U.S. Fish and Wildlife Service declare the deaths to be an unusual mortality event as defined under the Marine Mammal Protection Act, which the agency promptly did. The UME designation authorizes the federal government, working in coordination with Florida and nonprofit organizations, to investigate the cause of the die-off and to take immediate steps to prevent more manatees from dying.

Since 1991, 71 unusual mortality events involving marine mammals have been declared.

“Florida’s diverse animal life is deeply important to people in our state, and few creatures are more beloved than the manatee,” Murphy said in a statement. “I’m pleased that, in response to my request, the federal government has determined the spike in manatee deaths requires a swift and decisive response.”

The West Indian manatee is one of Florida’s environmental keystone species, Murphy added. The manatee population in Florida was only 1,300 when aerial surveys began in 1991 and grew to 6,300 as of 2016, 25 years later, because of conservation efforts.