Winter chill surges deaths of manatees
Chilly temperatures are rekindling a manatee die-off in Central Florida’s Indian River.
“Winter is here,” said Martine de Wit, a state veterinarian and scientist.
Along a Brevard County piece of the Indian River on Thursday, which turned warmer and sunny, a snapshot of the ominous, protracted plight of manatees came into vivid focus.
A pair of manatee calves lingered side by side nearly motionlessly in sun-pierced water not far from Florida Power & Light Co.’s shoreside electric plant south of Titusville. At their size, they likely would be clinging to a mother in normal circumstances, learning survival skills.
But manatees are suffering from starvation. Lush flats of seagrass they grazed on have been eradicated by a pollution-fueled ecosystem collapse. Mature males and females of nearly a half-ton and otherwise extremely resilient are perishing, taken down for good by the lethal synergy of cold and hunger, along with more vulnerable calves of barely 100 pounds.
The remains of a large male nearly 12 feet long was recovered two weeks ago from near Cocoa.
The seafloor beneath the young calves was barren sand, rippled with miniature dunes and without a blade of seagrass or clump of seaweed anywhere near.
Of Florida’s record loss last year of 1,100 manatees, the carnage was concentrated from January through March, when 258 perished in Brevard County, which by far had the most mortalities in 2021.
With nights dropping to the 30s in the past week, waters of Brevard’s Indian River are cooling now to the mid-60s for a thermal assault on naturally poorly insulated manatees.
The FPL power plant discharges a lot of warm water, providing refuge for manatees in an area otherwise a food desert.
State and federal authorities learned Thursday that attempts to feed lettuce to manatees at the plant were beginning to succeed, though modestly with several dozen seen eating the produce. “We can’t feed all of them,” spokesperson Tom Reinert said. An aerial survey recently found nearly 700 in the area.
As the pair of calves drifted listlessly in shallow water, a Florida Fish and Wildlife Commission patrol boat motored slowly by, towing a dead manatee, a big male.
The FWC vessel arrived at a public boat ramp north of FPL’s electric plant.
Waiting there was U.S. Fish and Wildlife Service’s Bobby Govan, a heavy-equipment specialist from Alligator River National Wildlife Refuge in North Carolina on assignment to Florida’s crisis.
He backed a heavy trailer down a boat ramp. The trailer carried a large, metal tub with a gate at its tail end. Govan winched the carcass into the tub, which had partially filled with river water.
The task, appearing practiced and effortless, was swift.
Govan soon was on the road to a remote site where another group with the Florida Fish and Wildlife Conservation Commission would conduct a field necropsy.
About an hour after it was pulled from the water, the big male, nearly 9½ long and perhaps 800 pounds, was ready for a cause-ofdeath examination alongside the carcass of a female about 5 feet long, 150 pounds and less than two years old.
The state’s wildlife agency knows volumes now about the distress caused by cold and starvation, but each animal’s condition is still documented in a variety of ways.
Manatees may evoke a cuddly, chubby character, but in reality they are dense beasts, suggesting the feel of super-tough canvas bags filled heavily with compacted sand.
Having done it countless times since last year, FWC biologist Kylie Lawson, with assistance from biology intern Niah Andueza went to work with razoredged knives, opening the mammals with precision.
Though not especially decomposed, the smell from the animals was strong. Swarms of flies descended instantly and the sky darkened with vultures, as often happens.
“I don’t know how they do it,” said Govan, respectfully of the two performing the necropsy, while staying back several steps.
The insides of the manatees were surprisingly complex, even elegant and heavily muscled.
While taking extensive photos, measurements and tissue samples, what Lawson noticed was that the two animals were liquifying their residual nodules of fat and layers of muscle tissue, all signs of starvation.
The younger manatee’s stomach contained dark liquid but no food and the bigger animal’s stomach held small bits of vegetative material that was preserved in an alcohol solution for identification.
During the first week of January, six dead manatee were recovered from along the state’s Atlantic coast, with three of those in Brevard. The second week’s count was 15 along the Atlantic and 10 in Brevard.
State officials will not provide data from the third week until it’s over.
Last year at the peak of the die-off, Lawson performed as many as 10 necropsies on some days and is mentally preparing for the possibility of dealing with a high toll again as the Indian River grows still colder. She maintains clinical dispassion but the exams are hard work.
“We do this because we care,” Lawson said.
On Thursday, the manatee death procession in Brevard — a carcass towed
to a boat ramp and trailered to the bare-ground site for a necropsy — was repeated
four times.