Alarming manatee death toll in Florida prompts calls for endangered status

The deaths of almost 2,000 manatees in Florida’s coastal and inland waterways over the last two years has provoked an alliance of environmental groups to demand an urgent reclassification of the species to officially endangered.

The advocates, led by the non-profit Center for Biological Diversity, insist the US Fish and Wildlife Service (FWS) made a critical error in 2017 by prematurely downgrading the status of the giant aquatic mammals from endangered to merely threatened.

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The move, they say, removed crucial federal protections to the species, sometimes also known as the sea cow, and allowed an almost unchecked decline in numbers after a previous revival.

During 2021, 1,015 manatees were killed, according to the Florida fish and wildlife conservation commission, largely through starvation as pollution and habitat loss destroyed huge areas of seagrass vegetation they rely on for food.

Another 745 deaths have been recorded this year to 18 November, a two-year drop in numbers that represents 19% of the Atlantic population, and 13% of all manatees in Florida, the alliance states.

“With Florida’s manatees dying by the hundreds, it’s painfully clear that the 2017 federal decision to downlist the species was scientifically baseless,” said Ragan Whitlock, a Florida-based attorney for the Center for Biological Diversity.

“The Fish and Wildlife Service now has the opportunity to correct its mistake and protect these desperately imperiled animals.”

The alliance, which includes Harvard Law School’s animal law and policy clinic, the Save the Manatee Club and Miami Waterkeeper, has petitioned the interior secretary, Deb Haaland, and FWS director, Martha Williams, for the change.

“Since the manatee was downlisted to threatened in 2017, it has become more imperiled and will continue to be adversely impacted by increasing natural and man-made threats,” they argue in the 156-page document.

“A growing human population and increased commercial development will only exacerbate these existing threats, and the ongoing effects of climate change … will compound damage to the manatees’ critical habitat.”

FWS has 90 days to determine whether restoring the manatee to endangered status is warranted. If it does, it has a further nine months to complete a review of manatees’ status.

In a statement to the Guardian, FWS said it is aware of the groups’ request, and that “service staff will review the petition through our normal petition processes”.

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A species is considered “endangered” under the Endangered Species Act if it is “in danger of extinction throughout all or a significant portion of its range”. A “threatened” species may become endangered in the foreseeable future.

Environmentalists blame pollution from wastewater treatment plants, leaking septic systems, fertilizer runoff and other sources for poisoning waterways where manatees were once abundant, and killing off seagrass.

Particularly affected is Indian River Lagoon, where the alliance says more than half of sampled Florida manatees are chronically exposed to glyphosate, a potent herbicide applied to sugarcane and aquatic weeds.

Discharges from Lake Okeechobee containing glyphosate have also resulted in higher concentrations of the herbicide in the Caloosahatchee and St Lucie rivers, the advocates say.

“With astounding losses of seagrasses around the state, we need to address water-quality issues to give the manatee a fighting chance to survive and thrive,” said Rachel Silverstein, executive director of Miami Waterkeeper.

The vegetation shortage is so critical that authorities are relaunching a feeding program introduced last year that provides lettuce in areas where manatees gather. When the program ended in April, more than 202,000lb of lettuce, funded mostly by public donations, had been distributed, with agency officials saying it had “worked really well”.

Savannah Bergeron, an eighth-generation Floridian and student attorney at the Harvard animal law and policy clinic, said restoration of an endangered status for manatees would be an important first step.

“The current long-term threats faced by the manatee will take years or even decades of concerted action to solve,” she said.

“The absolute least we can do is ensure that manatees are given the protections they deserve under the Endangered Species Act, especially since they’re so important to our coastal ecosystems and are one of Florida’s iconic species.”