Few vignettes show how human activity has affected wildlife more than the Florida Power & Light plant scene at Cape Canaveral. Hundreds of manatees bask in an intake channel on its southeastern edge, drawn by the warm waters. These manatees are hungry. Pollution has decimated their usual menu of seagrass in the Indian River lagoon. Many died of starvation: 1,101 died in Florida in 2021, and in December 2022 the official estimate was nearly 800 deaths. Along the canal, members of the Florida Fish and Wildlife Conservation Commission toss lettuce at them.
“It’s just emblematic of the seriousness of the situation,” says Rachel Silverstein, executive director of environmental nonprofit Miami Waterkeeper. “The point where we would need to artificially feed a wild animal because its ecosystem is so destroyed that it cannot find food for itself is quite extreme.”
The supplemental feeding program began in early 2022 and restarted this winter, due to the persistence of what marine mammal experts call an “unusual mortality event.” “It probably kept the manatees alive,” Silverstein says of the feeding program, “but it’s not a sustainable condition for long-term manatees to have to rely on an artificial food source.”
A lasting solution will require a long process of environmental restoration, which is partly ongoing, but it is a significant task, which has put local conservationists at odds with state and government policymakers. federal. And it’s complex, thanks to the peculiarities of the Florida coast and the sea cows dear to its human inhabitants.
Like most Floridians, manatees are picky about water temperature. It’s simply because they don’t have a lot of body fat. “People think it’s a big marine mammal, so it has a lot of fat, like a whale, dolphin, seal, or sea lion,” says Aarin-Conrad Allen, marine biologist and doctoral student at Florida International. University. Because they’re not well insulated, when the water drops below about 68 degrees Fahrenheit, they meander to warmer areas. “That’s why they go to these power plants,” he says, and that’s what draws so many people to the Indian River Lagoon, which stretches about 160 miles along the space coast of Florida.
But over the past 50 years, the human population of Brevard County, home to the Indian River, has nearly tripled. Human activity has simultaneously increased agriculture in the area, led to more boating accidents that injure manatees (96% of them have at least one propeller scar), dried up Florida’s historic Everglades, and flooded its waterways from pollutants. Because Florida sits on porous bedrock (“essentially the Swiss cheese of rocks,” Silverstein says), water and pollutants move easily through groundwater. “Everything that happens on the surface also happens underground,” she says.
This means that agricultural discharges and sewage leaks have raised levels of nutrients like phosphorus and nitrogen in nearby waters. This additional fertilizer leads to the proliferation of microalgae, which prevent sunlight from reaching the seagrass beds. Dead grass beds can further fertilize the flowers. This cascade of pollution has destabilized Florida’s ecosystem for plants and herbivores; scientists estimate that about 95 percent of seagrass is dead in parts of the Indian River Lagoon. Without them, the manatees also die.