On December 7, 2021, NOVA Digital Editor Alissa Greenberg visited ZooTampa’s David A. Straz, Jr. Manatee Critical Care Center to see up close how rescued manatees are recovering and regaining strength amid an ecological crisis and widespread starvation.
10:15 a.m. It’s feeding time at the manatee critical care center at ZooTampa, and the calves are ready and waiting. Even before the staff brings bottles of thick formula over to the pool where they are swimming, four sets of fuzzy nostrils break the surface, whiskers wiggling. “As you can see, they know it’s time,” says Animal Care Associate Kelcey Innes. The calves, which are all smaller than a duffel bag but may someday weigh close to 1,000 pounds, suck down the formula, then chew on the bottles’ rubber nipples playfully.
There will be more food soon enough—calves at the center are fed every four hours around the clock. But for now, Innes and coworker Sabrina Sauseda have a different task: watch for manatee farts, proof of digestive systems in working order. After a few minutes, Sauseda spots telltale bubbles. “Calliope had gas!” she announces.
The center keeps up this intensive feeding schedule because if the calves were still nursing with their mothers, they would be gaining at least a pound a day. But these calves are orphans, part of an ongoing manatee crisis in Florida.
Manatees are in trouble all over the state—particularly on its Atlantic (east) coast, they are starving. Last year was the deadliest on record, with more than 1,100 manatees dead, close to 15% of the state’s population. The reason is seagrass: The Florida coast is home to what were once two of the largest undersea meadows in North America, and the plant makes up much of the manatee diet. But Florida's seagrass ecosystems are collapsing, due largely to fertilizer and development runoff. In the Indian River Lagoon, once one of the continent's most productive estuaries, seagrass has declined an estimated 95% in the last 10 years.
As one of four manatee critical care centers in the country, ZooTampa is caring for 23 manatees on this December morning, double its historic capacity. A mother manatee may feed her calf until she starves, so the facility has also taken on an unprecedented number of calves in the past year, left alone after their parents perished. As their state attempts to clean up its waterways, the staff at ZooTampa are working overtime to save the animals that mean so much to the soul of Florida.
10:35 a.m. It’s also time for morning tube feeding. Two new residents have arrived within the last week, along with the early winter chill. Both were suffering from cold stress; one had a fresh boat propeller injury across his face. And they both need to eat while they convalesce.
When a new manatee comes to the center after rescue by the Department of Fish and Wildlife, Animal Care Supervisor Jaime Vaccaro and her staff check its blood levels, respiration, and measurements. Then they set the new resident up in one of three medical pools that make up the hospital’s intensive care area. Each of these interconnected pools is equipped with its own heater, a vertical gate that can be lowered to cut off access, and a hydraulic floor that can be raised and lowered. This feature allows the staff to both customize the environment and raise the manatees out of the water for medical care.
Last week’s adult arrival, Corduroy, is in too much distress to eat. After they use the hydraulics to lift him out of the pool, Vaccaro and Innes take some of Corduroy’s blood, then gingerly thread a length of plastic tubing down his throat. His tail flaps a little, but he calms and accepts the liquid quietly. Manatees’ complicated digestive systems are especially sensitive, so the staff tube-feed Corduroy multiple times a day to make sure he stays hydrated and maintains his weight until he’s ready to eat on his own—a process that could take months. Manatee digestion is “like the engine of a car,” Vaccaro says. “If they've been sitting for a while, they might not start back up right away.”
Director of Conservation, Research, and Behavior Tiffany Burns connects the increasing number of manatee patients with Florida’s persistent water quality problems. “They look big and full of blubber, but they’re very muscular,” she says. “A lot of that body is intestines.” Without much insulation, manatees are very sensitive to temperature. If they swim in too-cold water long enough (anything under 68 F) they develop cold stress, which manifests outwardly in a frostbite-like icing of white, peeling tissue visible on the flippers and muzzles of many of the animals here. And if they stay even longer, they may develop pneumonia, hypothermia, and organ failure. Manatees typically migrate to warmer water during winter months, but those areas that could once support many manatees in a cold snap no longer have enough seagrass to feed them.
10:45 a.m. It’s feeding time (again) for the general manatee population housed at the front of the center in two broad pools backed by fake rock walls frequented by very real snowy egrets and great blue herons. Here, meals start at 7:30 a.m. and snacking continues almost without pause all day.
On the path between the pools, Intern Olivia Callitsis is unloading heads of endive, escarole, and romaine lettuce from a pallet and stuffing them into a length of PVC pipe with a long hole in the side, so the greens spill out like a planter. A manatee consumes 10%-15% of its body weight daily, and occupants of the two main pools eat through some 1,200 pounds of produce a day. That makes the manatees the most expensive animals to feed at the zoo, costing some $40,000 a month. Burns says the money mostly comes from gate fees and private donors.
With a gentle push, Callitsis launches the pipe into the pool, where it bobs gently before sinking. “You can throw it on the surface,” she says of the lettuce, “but this really mimics the natural environment. They have to dive down, work for it a little.” Soon, the surface is broken here and there by smooth gray backs and broad tails, then wrinkly, whiskery snouts munching intently.
The inhabitants of the general population pools are mostly at the end of their stay here, with durations that average five months for adults and two years for calves. Because the goal is release, Vaccaro and her colleagues do not engage in the typical zoo enrichment activities, instead switching the manatees between pools frequently so they don’t get too used to their surroundings. And as soon as the calves are stable enough, Vaccaro buddies them up so they learn natural behaviors.
2:00 p.m. It’s time for the second bottle feeding of the day. Innes and Sauseda carry bottles with a mix of vitamins, baby formula and oils like red palm fruit and macadamia to the medical pools. They lean over and slap the surface to get the calves’ attention and let them know where the goodies are. Small snouts appear and latch onto the bottles, clouds of formula spreading in the water.
Burns is aware of the appeal of manatee calves in particular. “Everybody loves manatees and wants to help,” she says of the zoo’s visitors, but they don’t always connect their decisions at home with the fate of the animals they love. “Everyone wants that big, beautiful green lawn, perfectly manicured. But it comes at a cost.”
She’s referring to the role nitrates from fertilizers play in fueling algae blooms, which can block out the sunlight seagrass needs to survive. Similarly, pollution from agricultural runoff, construction, and sewer outflow can cloud coastal waters, starving out seagrass. Sick and dying grass can no longer stabilize the sea floor, which means even more sediment floats up into the water—compounding the situation and giving algae the upper hand, says Lead Biologist Ryan Brushwood of aquatic restoration company Sea & Shoreline. What started as a little algae quickly grows, and ultimately the system hits an inflection point.
Some 70 miles north of Tampa, the community of Crystal River saw exactly what that looks like when, in the 1990s, an area that had once hosted some of the state’s largest seagrass meadows was overcome by muck and an algae called Lyngbya wollei.
“There was no grass whatsoever,” remembers Lisa Moore, president of the non-profit Save Crystal River. “There were huge plumes of algae growing everywhere.” The water stank; dogs that swam in it got sick. And the population of manatees that had long flocked to the area for its warm springs found little food. In 2015, Save Crystal River hired Sea & Shoreline for a multiyear project: sucking up millions of pounds of muck and water and treating it with a polymer that binds with particles suspended in the water so they become heavier and settle out. The leftover muck is taken to farms to use as fertilizer. Then, Brushwood and his colleagues plant new grass, which they keep in underwater cages to protect it from nibbling manatees until it is well established.
Since the plant grows in rhizomes, underground shoots that extend long lateral stems in all directions, it can cover a lot of ground quickly. So far, Save Crystal River has replanted 300,000 plants covering 54 acres out of a planned 92—and those 54 acres have naturally expanded to over 200. The water is clearer, fish and crabs have returned—and so have manatees, in abundance. Save Crystal River hopes its model can be repeated elsewhere in Florida, perhaps including the Indian River Lagoon.
3:15 p.m. Vaccaro begins shifting manatees around in the medical pools, opening and closing the vertical gates to make space for Pebbles, a mostly-recovered adult who’s been at the center for close to a year. She was in critical condition when she was rescued, with cold stress and propeller wounds that weren’t healing. But she’s made a remarkable recovery and moved into the general population pool not long ago.
Pebbles’ bloodwork has recently shown that she might have a brewing infection, though, so she’s receiving antibiotic injections. But after a few days of shots around the same time, Pebbles has figured out the pattern. Vaccaro slips into the water to try to isolate her into medical pool 3 but, in a flash, Pebbles breaks free, using the full force of her tail to twist through the open gate and into the shallow canal that connects the medical and general population pools. Vaccaro radios for help.
“She knows she’s going to get an injection, and no one likes those,” Innes says. Instead, Pebbles plays a watery game of cat and mouse. Whenever Vaccaro moves toward her, she glides powerfully to the other side.
After half an hour, the staff is on the verge of giving up, aware that Pebbles is stronger than they are. “We try not to force them to do anything they don’t want to do,” Innes says. “But these treatments save their lives, so we have to find that line of when to intervene.”
4:25 p.m. As the winter sun starts to dip lower, Vaccaro prepares for the night, loading up PVC pipes full of lettuce and letting whole escarole heads thwap on the surface of medical pool 3 until it’s silty and bobbing with leaves. The buffet of greenery is enough to keep several hungry manatees fed into the wee hours, she reasons—plus, it might tempt Pebbles back into the pool on her own.
4:30 p.m. To Vaccaro’s surprise, the tactic works. She moves quickly to drop the gate and hem Pebbles inside.
4:40 p.m. With the floor of medical pool 3 raised all the way up, the heads of lettuce are suddenly beached—and so is Pebbles. Vaccaro and a colleague cover her with a heavy mat, at times using their bodies to keep her steady. The first needle breaks, and Pebbles squirms away, but a second attempt to inject her succeeds. Vaccaro heaves a sigh of relief as Pebbles is lowered back into the pool.
4:55 p.m. The zoo is closing, but the center’s day never really ends. Vaccaro moves from her antibiotic triumph to mixing up formula for the calves in a cramped office behind the pools, then uses the waning light to tube-feed all three adult manatees in the medical pools in quick succession.
When it’s recovering adult Flapjack’s turn, he lies quietly as the slurry of romaine lettuce and formula slips down his throat. He’s gained 70 pounds since he arrived, Sauseda says, showing a photo from the day he arrived with ribs protruding and belly sunken. The difference is still obvious between Flapjack and the other manatees, especially in the definition of his head and the slightness of his torso. But when Vaccaro and Sauseda finish feeding him, his eyes look somehow brighter.
Florida made headlines this winter when it went ahead with a controversial program to feed wild manatees in the Indian River Lagoon, in part with the hope of helping individuals like Flapjack so they don’t need to be treated at places like the center. In Burns’ mind, the most urgent question is how to stop the same thing that’s happened on the state’s Atlantic coast from repeating around Tampa, on the Gulf side. “Let’s learn from this,” she says. “We don’t want to wait for another largest death toll in a year. Let’s get ahead of it and make sure our animals have clean water.”
State funds made available for water cleanup are a start, and education is a big part of any solution, she says. But such an urgent and entrenched problem needs a multipronged approach. “You can’t rely solely on education, on rehab, on laws—people break laws all the time. People have to work together in multiple ways to try to solve these problems.”
As Flapjack returns to the water, Vaccaro pauses to make sure all her charges are breathing and swimming well after their feeding. She’s also made sure that every manatee has appropriate company overnight—no “busybody” animals that will annoy their poolmates, no males and females that might cause trouble together. Then she walks back to the office for final evening preparations and, eventually, to head home. The center finally lies calm in the half-dark, silent but for the lap of water and occasional hiss of a manatee’s breath.
But someone will be back at 10 p.m to feed the calves.