Manatee deaths reported in Florida during the past 50 years included nearly 5,000 from boat strikes, water structures and red tides. But across that span of mortalities, there has never been a die-off as gruesome as the one that occurred in Florida in the first half of 2021, when 677 carcasses were counted along Florida's east coast. Half of those were in Brevard County's portion of the Indian River, a coastal lagoon in biological collapse due to pollution.
Partly because of the pandemic, necropsies were not done on much of the dead manatees in Brevard. But early on, authorities knew that winter cold was not the culprit. They could tell from the lack of seagrass in the lagoon and the manatees' contorted bodies that they were dying of malnutrition.
Widely beloved as irresistibly cuddly, manatees are among Florida's strongest, hardiest creatures, able to heal from the most vicious of propeller wounds. But death by starvation is as inhumane as any of the assaults Florida has inflicted on manatees. Caretakers said suffering lasted months-- with many losing nearly half of their weight. While still alive, bones pierced thinning skin and shocking to veterinarians, heart, liver and other organs were liquifying.
To survive, the animals' bodies began consuming fat and muscle. They lost buoyancy and, becoming too exhausted to swim, could no longer raise their heads for air. An untold number survived, but became strikingly emaciated. Experts fear their poor health will slow the species' reproduction for years.
Rescue efforts for 80 manatees were launched, a task requiring 10 personnel for each animal. Unfortunately, many were too far gone-- seven died during rescue and eight died in intensive care. So far, 37 have been revived and put back in the wild. According to Martine de Wit, a veterinarian with the Florida Fish and Wildlife Conservation Commission, the root cause is "an ecosystem in trouble."
Lauren Hall is one of Florida's top researchers of seagrasses. She is from the St. Johns River Water Management District and oversees monitoring and mapping of seagrass in the Indian River. In 2015, the Indian River was suffering the beginning of seagrass losse-- but the river offered a carpet of green for grazing manatees. But six years later, Hall found a lagoon floor that resembled a sandy desert. On a tour of the river for an Orland Sentinel reporter, she pointed out only the occasional clump of seagrass-- a modest rebound of seaweed called Caulerpa, which can anchor the lagoon's sandy bottom as a precursor for the return of seagrass. In the past decade, nearly 58% of seagrass beds—or 46,000 acres—has vanished from the Indian River Lagoon. Remaining beds contain about 10% of the original amount of seagrass.
For decades, the lagoon has been afflicted by the usual Florida maladies: urban storm water, agricultural runoff, lawn and farm fertilizers, too many septic tanks and leaky sewer systems. To make matters worse, Brevard's share of the lagoon gets no ocean tidal flushing-- any pollution draining to the Indian River stays there.
Scientists began observing the exacting toll of this environmental abuse just a few decades ago. Pollution spawned massive, intermittent and unpredictable outbreaks of microscopic algae, which darkened the water and cast lethal shade on seagrass and seaweed.
Larry Williams,the U.S. Fish and Wildlife Service's ecological director in Florida, described the phenomenon in stark terms. "The prior ecology was a clear-water system where sunlight could get down through the water and get to the seagrass. In other parts of the world, they've seen systems like that shift to a new, steady state of murky water dominated by algae." he said. "Some of the scientists say that what we are seeing right now is the flickering transition to that new, steady state."
Florida environmentalists have an axiom: "east to break and difficult to repair." While millions of Florida state funding is starting to underwrite lagoon restoration, such efforts are very time-consuming to plan and execute. Duane De Freese, executive director of the Indian River Lagoon National Estuary Program said that the effort will actually require an estimated $5 billion and 20 years or more. "We need to focus hard on the plumbing," De Freese said. "Septic, storm water, both urban storm water and the larger, stormwater regional projects."
One culprit is the warm-water discharges from the Florida Power & Light Co. generating station just south of Titusville along the lagoon. During winter, manatees are drawn to warm waters of power plants or springs. The FPL plant is the only such source along Brevard's share of the lagoon. According to Gil McRae, director of the Florida Fish and Wildlife Research Institute, that area had thus become a magnet for large numbers of manatees and as a result experienced a significant seagrass decline.
Patrick Rose, executive director of Save the Manatee Club, believes that the wildlife service should push the U.S. Environmental Protection Agency to impose more stringent pollution rules for the Indian River-- and help ensure that a $5 billion seagrass restoration effort succeeds. "It's an investment we can't afford not to make."
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