The Race to Save Florida’s Manatees

Researchers are nurturing sick and injured animals back to health while working to protect natural springs and curb seagrass decline

Rescuers Reintroducing Manatee
A SeaWorld team prepares to release a rescued manatee. SeaWorld

In May 2022, Stacy DiRocco, a senior veterinarian at SeaWorld Orlando, received a call. A robust female manatee she’d assessed four months prior in a Florida waterway had just been found with a boat-strike injury to the side of her body. A photo in a text message that followed showed the damage. “It was pretty extreme,” DiRocco recalls. “It did not look like she would survive.”

A rescue crew brought the manatee and her newborn calf to SeaWorld, one of 20 organizations in the 22-year-old Manatee Rescue & Rehabilitation Partnership (MRP), a consortium of research institutions, government agencies and nonprofit conservation groups. Injuries to the animal, dubbed Reckless after Sergeant Reckless, a decorated horse who served the U.S. Marines during the Korean War, were catastrophic. Her shoulder blade protruded from a gaping, foot-long wound. Her left pectoral flipper had been rendered useless, and she was unable to feed her calf from that side. Miraculously, the calf, whom rescuers nicknamed Churro, was healthy.

“When I saw her, and how much of a fighter she was, I made the decision to just go all in see if we could give her the best chance possible,” says DiRocco.

Following nine groundbreaking surgeries, physical therapy, supplemental feeding and a variety of treatments for ailments such as kidney failure, Reckless has made a remarkable recovery. DiRocco’s team expects to soon return mother and calf to Florida waters.

Veterinarians Operate on Manatee
Veterinary surgeons work to correct Reckless’ extensive injuries. SeaWorld

The results for manatees in Florida are not always so positive. Historically, boat strikes and entanglements in fishing gear have topped their causes of death. Red tide, a type of harmful algal bloom caused by overgrowth of Karenia brevis, a species of naturally occurring phytoplankton exacerbated by pollution, acts as a neurotoxin in many marine animals and has been responsible for extensive manatee deaths in at least ten different years since 1996.

Starting in 2020, manatee deaths surged among the already threatened population, mainly in the Indian River Lagoon area. In 2021, an estimated 1,100 manatees died. While the number dipped to 800 in 2022, that’s still above the five-year average—significant in a population whose numbers total only about 7,000.

The accelerating die-off was precipitated by the decline of seagrass, the manatee’s main food source, caused by climate change and nutrient pollution, such as from fertilizer runoff. The marine mammal consumes approximately 10 percent of its 1,200-plus-pound body weight in seagrass per day. Such voracious eating habits help maintain the balance of waterway vegetation. “We talk about manatees being the canary in the coal mine,” says James Powell, chief zoological officer for the Clearwater Marine Aquarium, an MRP partner. “They play a very important ecological role in consuming and cycling nutrients. By the time manatees die, everything else that’s depending on those seagrasses—all the shrimp and fish, for example—they’re gone, too.”

Chip Deutsch, a research scientist with the Florida Fish and Wildlife Conservation Commission, says, “We saw the seagrass loss coming.”

In Florida Bay in the 1980s, a lack of freshwater funneling into the harbor caused a spike in salinity levels and seagrass die-off. The waterway eventually recovered, but a 2015 summer drought followed by record amounts of winter rain triggered the proliferation of the chemical hydrogen sulfide, which killed more than 62 square miles of the aquatic plant.

In the Indian River Lagoon, part of a 156-mile, biologically diverse estuary and a preferred winter habitat of the manatee, seagrass shrank by 25 percent between 2011 and 2021. In a report released last year, the Southwest Florida Water Management District documented the loss of more than 4,000 acres in Tampa Bay and 577 acres in Sarasota Bay since 2020. As the seagrass has perished, the manatees have slowly starved to death, their rib cages and skulls easily discernible beneath a diminishing layer of subcutaneous fat.

Researchers have worked toward restoration of the vegetation. Pilot projects are underway to grow seagrass in nurseries, for replanting in Florida’s bays and estuaries. But, says Deutsch, “We’re not going to plant our way out of this mess.” Restoring a single acre can run upwards of $20,000. And it doesn’t address the underlying problem: “We need to improve water quality. If you go back and plant seagrass but the water quality is turbid, it’ll die,” he says.

Improving water quality requires a multipronged approach: decreasing runoff, improving wastewater treatment and reducing the use of septic tanks, enhancing storm-water management, and preventing the overharvesting of beneficial shellfish species, which act as filters. In the country’s fastest-growing state, where people flock to the coast and growth-management laws have been largely abolished, agricultural and urban development have run mostly unchecked for decades.

“We’ve been mortgaging our environmental future,” says Patrick Rose, executive director of MRP member Save the Manatees Club. “We’ve been growing in way where we’ve been incurring debt. In places like Indian River, Mother Nature foreclosed. We’re still seeing a lot of permitting for development that isn’t meeting sustainable standards.”

While the current state government has signaled an interest in water quality, the 2023 legislative session ended with only a modest fraction of 14 proposed bills passed. In the state’s new budget, $300 million has been earmarked to mitigate sea-level rise, $104.9 million will go toward restoration of the Indian River Lagoon, $50 million will go toward rehabilitating Florida’s natural springs, and $12.8 million will go toward combatting algal blooms.

All are positive steps that will help the environment and marine animals. But without enforcement of the Clean Water Act, which the Environmental Protection Agency has delegated to state agencies, the funding might have minimal effect. In response, the Save the Manatees Club has filed a lawsuit against the EPA to reinstate a portion of the law to prevent degradation of habitats that support threatened or endangered animals. Even if they win, Rose acknowledges, it’s only the beginning of balancing the sustainability equation.

Manatee Released Into the Wild
A rescued manatee swims away after being returned to the water. The orange marks, made by a nontoxic paint stick, help scientists identify the manatee by his scars. SeaWorld

Still, public awareness of the manatees’ plight has brought about some positive changes. Iske Larkin, director of the Aquatic Animal Health Program at the University of Florida College of Veterinary Medicine, points to slow speed zones along critical waterways as one of the most significant developments, because it reduces manatee collisions with boats. She observes, however, that those speed limits aren’t always enforced.

Another conservation bright spot is rescue and rehabilitation. The process usually entails capture aboard a boat, followed by transport, in a specially fitted truck, to a rehabilitation center, such as SeaWorld, Clearwater Marine Aquarium or Jacksonville Zoo and Gardens. SeaWorld currently has the largest facility, with five acres dedicated to critical and supportive care. In April, Clearwater broke ground on a new rehabilitation center that will significantly increase its capacity to care for animals in need.

Dozens of veterinarians, veterinary surgeons, wildlife biologists and technicians are involved in the treatment of a rescued manatee. Restorative care can be as simple as hydration and supplemental feeding with romaine lettuce—to the tune of 150 heads per adult animal per day. Treatment can also include diagnostic imaging, the administration of injectable and IV medications, and, in severe cases like Reckless’, amputations and other surgeries.

“The turnaround and success rate is pretty high once animals get into rehab,” DiRocco says. “You’re looking at 75 to 80 percent of animals that should be able to be returned [to the wild].”

In an average year, SeaWorld takes in 30 manatees for rehabilitation. But DiRocco notes they have already reached that number in the first half of 2023.

Manatee
A manatee swims through one of Florida’s many springs. Monica Ross, CMARI. Permit # MA37808A-2

Beyond rescue and rehab, a long-range strategy is key. This would include a revised Florida Manatee Recovery Plan—the last update was in 2001. Experts hope that Brevard County, which voted to institute a 0.5 percent sales tax to aid conservation efforts, will be a model for other residential areas. And local governments need to do a better job of educating residents on the impact of lawn fertilizers and other common household chemicals on the water and its inhabitants. Even if a resident isn’t directly dumping chemicals into the water, in a state that averages 55 to 60 inches of rainfall per year, storm-water runoff picks up pollutants from lawns, yards, parking lots and roads, and flushes them into lakes, ponds, bays and canals.

“If we’re ever going to solve these issues, it goes back to sustainability,” Rose says. “We need to educate on what you can do to not be part of the problem.”

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