Red Tide Manatees Are Released, But Unusual Deaths Continue
An Environmental Article from All-Creatures.org

From

Save the Manatee Club
July 2013

At least 272 manatees in southwest Florida died from exposure to red tide in 2013, with an additional 33 manatee deaths from this cause in 2012. Already in 2013, there has been unprecedented manatee mortality, with more than 683 deaths as of July 12th.

Redlee, one of the manatees who recuperated from red-tide poisoning at the Ellie Schiller Homosassa Springs Wildlife State Park in Homosassa, FL, is prepared for release on July 16th. (Photo by Samantha Emery, Save the Manatee Club Intern.)

A devasting red tide bloom that started in southwest Florida in September 2012 finally subsided and has completely dissipated. The water in that area is now clear and the red-tide-affected manatees have been released. At least 272 manatees in southwest Florida died from exposure to red tide in 2013, with an additional 33 manatee deaths from this cause in 2012. Already in 2013, there has been unprecedented manatee mortality, with more than 683 deaths as of July 12th.

Red tide acts as a neurotoxin in manatees, giving them seizures that can result in drowning without human intervention. Thankfully, if manatees exposed to red tide can be moved out of the affected area by trained biologists and stabilized at a critical care facility, their prognosis is very good.

Many thanks are due to the Florida Fish and Wildlife Conservation Commission (FWC), Lowry Park Zoo's Manatee Hospital, Lee County Manatee Park, Ellie Schiller Homosassa Springs Wildlife State Park, and other rescue and rehabilitation partners and volunteers who put in countless hours during the red tide crisis. Because of their help, many manatees were rescued in southwest Florida who otherwise would have perished .Fortunately, these manatees were found alive and were successfully rescued and transported to a critical care facility. Special thanks also go to Save the Manatee Club members and supporters who helped provide funds are needed to feed and care for the red-tide-affected manatees in rehabilitation at the Ellie Schiller Homosassa Springs State Wildlife Park. From June 13 - July 17th, 15 of the manatees who had recovered from red tide poisoning were released at various locations in Florida

However, another threat is still claiming manatee lives on the state's east coast in Brevard County. Since 2012, at least 111 manatees have died of unknown but presumed natural causes, possibly from a different toxin or toxic syndrome. With vast amounts of Brevard's seagrass wiped out from a huge die off, it is still not known if manatees may be accessing other food sources or contaminants that are making them sick and killing them. One theory is that since the seagrass is not available, manatees have switched to a different food source -- a macroalgae called Gracilaria -- that is getting into their digestive tract and killing them. Another theory is that the toxins are found on seaweed that manatees eat.

Veterinarians and scientists at the University of Florida are currently testing genes and proteins expressed when manatees are exposed to toxins. The study is funded in part by Save the Manatee Club and is designed to see if differences between affected and healthy animals carry the biological signature of an immune system responding to toxin exposure -- a signature they can then test for in the Indian River Lagoon manatees.

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