Foraging during nesting season is a social affair in the Everglades. In the Water Conservation Area of the central Everglades, hundreds of wading birds, including Roseate Spoonbils, and American White Pelicans gather to feast on concentrated pools of prey. Photo: Mac Stone

Conservation

Florida's Wading Birds Are Nesting In Droves This Year

An extra-wet rainy season shows that, given a chance, the Everglades ecosystem can bounce back from a century of abuse.

In the cypress woods of Audubon's Corkscrew Swamp Sanctuary, the ponds seemed to be boiling. It was a devilishly hot April day in the western Everglades, but it wasn’t heat roiling the water—it was fish: juvenile bowfin, catfish, and other freshwater species trapped in shrinking seasonal pools.

A who’s who of wading birds had descended on the banquet from nearby nest-laden trees. Great Egrets, Great Blue Herons, and Tricolored Herons stalked and stabbed. Roseate Spoonbills swung their beaks like metal detectors through the muck. White Ibises probed methodically, while Wood Storks line-danced through the shallows, bills ajar, snapping them shut when they bumped a morsel.

It’s a scene that played out across South Florida this spring, when abundant water created ideal breeding conditions. From coastal mangroves to tree islands in inland marshes, forest canopies dripped with pink and ivory as wading birds nested in some of the biggest numbers in recent memory. It’s too early for a final tally, but this year is poised to far surpass a solid 2017, when more than 46,000 nests of seven wading bird species were recorded.

Biologists have taken to the air, land, and water to search for nests in the Everglades Protection Area, which includes Everglades National Park and conservation areas to the north. Surveyors have counted 3,141 Wood Stork nests, more than double the 10-year average, and some 8,000 Great Egret nests, about 25 percent above average. White Ibises were breeding in droves, with 34,400 nests tallied, 50 percent more than usual. At one ibis rookery called Alley North, up to 18,000 pairs congregated, a possible record for the site. Viewed from a Cessna circling at 1,000 feet, ibises appeared as white sprinkles among the broccoli-colored willows; for miles around the colony, they clustered in pools dotting the sawgrass prairie, filling up on fish and crabs before winging it home. 

The Everglades are North America’s most important breeding area for wading birds, which have declined nearly 90 percent in the region since the early 20th century. As massive efforts continue to restore the hydrology of this iconic ecosystem, experts are hopeful this year’s resurgence of long-limbed waders proves that they have the resiliency to bounce back.

“Everything is not lost,” says Mark Cook, an avian ecologist with the South Florida Water Management District who edits an annual wading-bird nesting report. “We can still restore the system,” he says. “This shows how rapidly things can change when we get the water right.”

Last year South Florida experienced its wettest rainy season in more than eight decades, from biblical downpours in June through Hurricane Irma’s ire in September. Flooding damaged homes and property, but the soggy summer had an upside: It recharged shallow wetlands, mimicking historical habitat conditions that supported vast flocks of wading birds. 

 

Over the past century humans have drained half of the Everglades’ original 4,000-plus square miles for development and agriculture. The wide, shallow river that flowed south from Lake Okeechobee into today’s Everglades National Park and out to Florida Bay has been heavily engineered with canals, pumps, and dikes that divert water east and west. Drainage projects made room for farms and homes, but they also strangled the flow of water into the Everglades, robbing wading birds of wetland habitat—and, as a result, food sources. 

 

For millennia in the Everglades rain-fed south-flowing water filled up wetlands, which swelled with juvenile fish and crayfish. As water levels receded during the dry season, prey became stranded in shallow ponds. While that fish-in-a-barrel concentration isn’t so important for Great Egrets and other birds that hunt by sight, spoonbills, storks, and ibises find food by probing the shallows with their bills. They rely on these prey-dense pockets to feed their young and teach them to forage.

In the dry season after Hurricane Irma drenched South Florida, pools of concentrated fish have formed in the deeper regions of the Everglades, attracting wading birds. Here, a Great Blue Heron spears a blue tilapia in Corkscrew Swamp Sanctuary. Photo: Mac Stone

Today many shallow wetlands never fill up, forcing waders to breed elsewhere, or to wait until deeper pools retreat enough to make foraging possible, which can result in late-fledging chicks that are less likely to survive. Or wetlands may dry up too fast, leaving nestlings vulnerable to raccoons that alligator-filled waters would otherwise keep at bay.

 

Last summer’s heavy rains, followed by the gradual draw-down during the dry season, created ideal nesting conditions echoing the past. The flush of fresh water also helped dilute salinity and jumpstart prey-fish production in Florida Bay, the Everglades-fed estuary that lies between the mainland and the Florida Keys. Up to 400 pairs of Roseate Spoonbills nested there beginning in November—months earlier than in recent years and in line with their traditional breeding schedule, says Jerry Lorenz, Audubon Florida’s director of research.

A Great Egret in breeding plumage is backlit by a rising sun in Audubon's Corkscrew Swamp Sanctuary. Birds come from around the watershed to forage for fish in the pockets of deep water that form here during the dry season. Photo: Mac Stone

The striking birds also resumed nesting on mangrove islands, bucking their trend of colonizing inland areas to avoid salty, rising seas driven by climate change. “When your bill is nine inches long and you have six inches of sea-level rise, you don’t have any place to forage,” Lorenz says. Ocean currents, which slightly lowered local sea levels, appear to have provided a temporary reprieve this year, he says.

Rising waters may eventually put those islands off-limits for spoonbills, but that’s not what started their decline. “It was the lack of freshwater flow from the Everglades into Florida Bay,” Lorenz says, and only by replenishing that flow can we offset the saline ocean water entering the bay. “It’s imperative that we restore the Everglades to counteract sea-level rise, to keep that salt out.” 

Restoring the Everglades will require far more than a single spectacular rainy season. A $16 billion state and federal restoration program encompassing 18,000 square miles has begun to undo a century of damage, and several large projects to increase water flowing south are slated for the next few years. These efforts to replenish wetlands and restore hydrology patterns, experts say, could reset the historical timing of nesting and see the boom of 2018 become the new normal.

“A restored Everglades means a resilient South Florida,” says Celeste De Palma, Audubon Florida’s Everglades policy director. “A restored system would lead to getting the water right to support the thousands of wading birds that characterized the Everglades. That’s why we need to ensure restoration efforts don’t lag behind.”

Eighteen years into what was expected to be a 30-year effort, the work is nowhere near half done. Underfunding, political bickering, and sluggish bureaucracy have left many Floridians frustrated with the pace of restoration. But projects at last nearing completion will soon open the floodgates and begin fulfilling the effort’s promise. “It’s slower than we would have hoped,” De Palma says, “but I know we’re going to build momentum with all of these ribbon cuttings we foresee over the next five years.”

Renewing the flow of water will not only boost numbers in current breeding areas, it could also draw more waders back to traditional sites. A century ago early Audubon leader Thomas Gilbert Pearson reported seeing 100,000 Wood Storks in the shallow wetlands at Corkscrew Swamp Sanctuary, historically home to North America’s largest colony. Since then, an estimated 80 percent of the wetlands have been drained or filled, and in most of the past 10 years none of the federally threatened birds have nested at Corkscrew. Instead they’ve opted for marshes and managed wetlands in Georgia and South Carolina. 

Downpours last summer, the rainiest on record at Corkscrew, replenished the shallow wetlands, luring the birds back. Most of the 400 nests counted since December held two or three chicks, and sanctuary director Jason Lauritsen says that about half are expected to edge. “It’s so uplifting to see them,” he says. “This year is exceptionally exciting. It shows that if conditions are right, they will nest, and nest successfully.”

Lauritsen says weather alone won’t ensure the storks’ return. It’s essential to preserve wetlands that act as natural flood-controlling sponges—especially shallow wetlands where waders forage early in the nesting season. Despite Everglades restoration efforts, the Big Cypress Swamp watershed, which includes Corkscrew, lost more than 43 square miles of wetlands to agriculture and development from 1996 to 2010, federal data show.

To help counter that trend, Lauritsen’s team is actively restoring hundreds of acres where storks have again started to forage, and they’re hoping to partner with the state to acquire and manage thousands of additional acres. These efforts complement the broader Everglades restoration plan’s focus on replenishing wetlands. The Picayune Strand project, for example, will rehab more than 50,000 acres not far from the sanctuary. “We need to do our part and govern, restore, and manage accordingly,” says Lauritsen. “The birds will respond.”

Clamorous fluffballs that in April were just beginning to resemble storks, spoonbills, and ibises have since ventured out of their nests. They’re learning to forage for themselves in wetlands where they may one day return to gather food for their own chicks. Like their new Everglades home, they are full of promise.  

Video: Mac Stone

Air support provided by Gary Lickle in collaboration with LightHawk.

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