More than 70 years ago, Florida manatees made a life-changing discovery: The warm water pouring out of power plants makes excellent winter refuges.

The news spread, passed on from mother to calf. Thousands of manatees now survive the winter next to power plants that suck up cold ocean, use it to cool off and spit out water fit for a hot tub.

Such industrial discharges have been crucial to the ongoing recovery of the West Indian manatee. When it was first listed as endangered in 1967, fewer than 1,000 manatees remained in Florida. Today that number has jumped to more than 6,300, with more than half using man-made warm water refuges.

This month, the Fish and Wildlife Service announced that the population no longer qualifies as endangered under the Endangered Species Act. The agency is proposing to reclassify the species as threatened.

But FWS has yet to tackle the biggest threat facing manatees: the loss of those power plant hot tubs.

Manatees

Jim Valade, FWS's Florida manatee recovery coordinator, said he's optimistic that the agency will find a solution before power plants close or phase out "once-through" cooling. But he called it a "very significant concern."

"We need to figure out how to wean those animals" from power plant sites, he said. "Quite frankly, we're just not sure how to do that."

That uncertainty put the manatees in peril a decade ago, when U.S. EPA almost prohibited the once-through cooling used by most of Florida's power plants. Faced with expensive retrofits, power plants considered closing -- a move that could have left half the state's manatees to die of cold stress.

In the end, EPA decided to exempt older power plants, instead requiring performance standards to mitigate fish kills and other environmental effects. Most plants have since met those standards and "repowered" with natural gas.

Immediate crisis averted, the manatees at power plants continued to grow.


FWS, meanwhile, still has no official plan. The closest it has come is a draft written in 2004 and last revised in 2011. It lists some of the options: enhancing natural warm water springs, creating new man-made ones or slowly weaning manatees off power plants.

All would take time and money. Environmentalists worry that by downlisting the manatee, FWS may be sending the wrong signal to a public that needs to be on board for the long haul.

"They're all hung up on, 'We have more manatees,'" said Katie Tripp, director of science and conservation at Save the Manatee Club. "Yeah, you have more manatees who are addicted to industrial water."

A Florida tradition

The marriage between manatees and power plants is well known in Florida, where generations have grown up visiting the gentle giants at their favorite industrial havens.

Richard Gibbs, a spokesman for the Florida Power & Light Co., said he has met people who fondly remember walking right onto the property of the company's Riviera Beach plant to see manatees congregate in the outfall areas.

Security measures in the wake of the Sept. 11, 2001, terrorist attacks put a stop to that. But next month, FPL will open Manatee Lagoon, a $5 million visitor center next to the power plant. The company committed to building the center when it modernized the power plant, which reopened last year and runs off natural gas.

FPL also conducts tagging and aerial surveys of manatees at its facilities. Its Cape Canaveral plant provides a winter home to as many as 1,000 manatees, accounting for a large chunk of the state's total population.

Such actions reflect the concerns of customers and the realities of doing business in an area with unique wildlife, Gibbs said.

"We've long made a commitment to try to operate our facilities as a good steward," he said. "We obviously know that the business we conduct has an impact on the air we breathe and the water you consume. ... There's a price you pay for living in Florida."

Power plants that attract manatees are required to have protection plans that address how to handle outflow disruptions and ensure consistent warm water. The result is a network of warm water refuges that manatees find dependable, returning year after year.

Manatees have consequently expanded their range, wintering farther north. Before power plants, the vast majority of manatees spent the winter in the lower half of Florida, seeking out natural springs, deep spots and sunny shallows when the ocean hit 68 degrees Fahrenheit.

Power plants may have allowed manatees to return to their historical range. Some research suggests manatees wintered in northern springs in the 19th century before hunters cleared them out.

As the manatee population has grown, many have returned to such springs over the past few decades. For example, Crystal River National Wildlife Refuge about 90 miles north of Tampa draws hundreds of manatees in the winter. Their popularity with tourists prompted FWS to recently propose new swimming regulations there (E&ENews PM, Nov. 10, 2015).

But many more manatees cluster outside power plants, influencing their distribution. FWS separates Florida manatees into four "regional units" based partly on where they winter; two of those units rely on power plants.

Republicans have seized on the hundreds of manatees that show up at Big Bend Power Station near Tampa in their battle against EPA regulation. The coal-fired plant has become a winter home for between 500 and 700 manatees.

The plant's units are expected to last at least another 20 years, but Republicans assert that the Clean Power Plan could force the plant to close sooner.

House Natural Resources Chairman Rob Bishop (R-Utah) and Senate Environment and Public Works Chairman James Inhofe (R-Okla.) wrote a letter to EPA last year asking whether the agency should have consulted FWS on its greenhouse gas standards for new and existing power plants, using Florida manatees as an example of possible negative effects to endangered species (Greenwire, June 26, 2015).

Asked recently about FWS’s proposal to reclassify the manatee as threatened, Bishop said the situation “seems very ironical.”

"The manatee's recovery, according to the Obama Administration, is contingent on preventing habitat loss tied to power plant closures," said Bishop, referring to a description of threats in FWS's proposal. "Despite this, the Obama administration's carbon rule is likely to lead to the closure of plants providing critical warm water habitat to the manatee. From the committee's perspective this is a serious and unresolved conflict for both the manatee and the administration."

Valade said FWS remains "very concerned" about the Big Bend power plant and what a closure would mean for the manatees that rely on it. But he also emphasized that it was the only coal-powered plant in Florida that shelters manatees. Most now use natural gas and will likely be around for decades to come.

"I am optimistic," Valade said. But, he added, "this is such a huge problem. It has to have a solution. It's not one we can ignore or continue to postpone."

The momentum problem

At a news conference earlier this month, federal and state officials insisted manatee protections would not change.

Technically, ESA has slightly different provisions for endangered and threatened species. But agencies can issue rules to protect threatened species at the same level as endangered. In its proposed rule, FWS specifies that the manatee's reclassification "would not change the protection afforded to this species."

That level of protection, however, has not resulted in a plan to ensure warm water habitat.

"It's a little early to be patting everybody on the back when this is probably the biggest single management issue that remains to be done for the species and there's nothing in writing about what's going to be done," said Tripp of the Save the Manatee Club.

The Center for Biological Diversity made a similar argument earlier this month, citing not only the warm water issues but also continued deaths from boat strikes. FWS should not downlist the manatee "without a proven, viable plan for further reducing boat strike mortality and for preserving vital warm water habitat," Jaclyn Lopez, CBD's Florida director, said at the time.

The momentum to downlist manatees began in 2007, when FWS released a status review that found the manatee's population was large enough to make extinction unlikely over the next century. In 2012, the conservative Pacific Legal Foundation -- representing a local group called Save Crystal River -- filed a petition asking FWS to act on the review and downlist the species.

FWS is legally required to respond to such petitions. When the agency was slow to respond, PLC sued. Under a court deadline, FWS released this month's proposed rule to downlist the species.

But even the proposed rule emphasizes that power plants "are not permanent reliable sources of warm water." It predicts that the current network of plants will endure for another 40 years and then will close.

FWS still sees the extinction risk as low. It partly relies on a recent analysis from the U.S. Geological Survey that estimated a less than 1 percent chance that the population will dip below 250 adults over the next 100 years.

"The loss of the power plants is not going to make the Florida manatees disappear," Valade said, later adding: "I think the difference between endangered and threatened, as much as anything it's about imminence. ... We really don't view the Florida manatee as being in danger of extinction in the near or immediate future."

Some experts have still urged caution in downlisting the species.

David Laist, a policy and program analyst at the Marine Mammal Commission, has released several studies on manatees' dependence on power plants and the looming problem of weaning them. A 2010 article -- written with Mote Marine Laboratory scientist John Reynolds -- contains a blunt warning.

"Given the fundamental importance of warm-water habitat for winter survival of manatees, it is essential that such decisions carefully consider the availability of winter habitat and the effects of impending power plant closures on future manatee abundance," they wrote in the article, which appeared in Marine Mammal Science. "Decisions to relax protection efforts would be short sighted at best and possibly seriously set back recovery efforts."

Freezing in place

One uncertainty that dogs FWS is whether manatees will find a new winter refuge on their own when their preferred power plant closes or stops pumping out warm water.

The agency has little to go on. But a few cases suggest manatees could die as they wait for warm water that never comes.

In 1985, the Fort Myers Power Plant shut down for 20 days. Despite three mild cold fronts, the manatees did not leave the area. They were still there when the plant started back up. Seventeen years later, when the plant had to temporarily shut down again, it installed a water-heating unit.

The relocation of a cardboard box manufacturing plant in 1997 provided additional clues. At the time, a small number of manatees spent the winter in the plant's heated discharge next to Amelia Island. When the plant moved, most manatees did not go south to known warm water refuges, and some died of cold stress.

Laist, who did not respond to an interview request, has asserted that South Florida does not hold enough warm water havens to support manatees who now rely on power plants. A 2013 paper in PLOS ONE, for which he was the lead author, suggests that natural warm water springs in North Florida may be the best replacement.

That would mean identifying springs and ensuring access for manatees -- as well as making sure they get there and return year after year. Most power plants are decades old, and generations of manatees have learned they are their winter home.

Tripp said ideas have included heating a barge and playing Pied Piper to manatees. Other observers hope that if federal and state officials restore nearby habitats, manatees might find it on their own.

Tampa recently restored Ulele Springs, which had been filled in a century ago. A few manatees were spotted last winter, raising hopes that other restoration projects might similarly draw in manatees.

Other springs in the state are blocked by locks and dams or capped during near-constant development. Some no longer exist, the water long gone due to agriculture and the household needs of a growing population.

"You're talking a huge amount of effort and money and time to make sure the natural habitat is protected or restored so that all these manatees that exist now have a natural habitat to go to," Tripp said. "We've got a little bit of a reprieve with the repowering, but if these people think they can downlist and still have the momentum they need ... they're just going to be digging their heels in protecting what they had."