Deadly Disease Stalking Lagoon Manatees

By JIM ASH
WFSU-FM
July 20, 2016

Biologists say a mysterious disease is making a comeback in the northern Indian River Lagoon, where nine manatees have died since the end of May.

The latest deaths bring the total to about 150 in the past four years, says Save the Manatee Club science and conservation director Katie Tripp.

The deaths don’t appear to be related to the massive toxic algae bloom plaguing Martin and St. Lucie counties, Tripp says. Instead, scientists think manatees are eating a toxic weed as sea grasses decline in the northern part of the system.

“It’s in the system, or it’s back in the system, or maybe it’s always been there, but now it’s returning to look like a food source to these animals.”

Tripp blames the problem on nutrients from agricultural and residential runoff, including septic tanks.

Martine deWit, a lead veterinarian with the Florida Fish and Wildlife Conservation Commission, says the disease may have never left, but gone dormant. She says it strikes rapidly, causing an otherwise healthy animal to drown.

“We believe that the switch in diet causes an upset in their gut and the reaction that’s associated with that gives them an acute upset that’s causing them to die very acutely.”

The algae bloom in the southern end of the 150-mile long lagoon is tied to massive releases of polluted water from Lake Okeechobee. The algae is toxic, but deWit says apparently not to manatees.

However, she is urging anyone who sees a stricken manatee to report it to 1-888-404-3922.