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

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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.

From mangroves along the coast to hardwoods clustered in inland marshes, South Florida’s forest canopies are dripping with pink and ivory. This spring Roseate Spoonbills, Wood Storks, and other wading birds are nesting across the region in some of the biggest numbers in recent memory.

This year’s colossal colonies of long-limbed nesters has experts hopeful that as work continues on a massive effort to restore this unique ecosystem’s historical hydrology, birds and other wildlife will bounce back after decades of decline. “This has the potential to be a gigantic year” for wading birds, says Jerry Lorenz, director of research for Audubon Florida. “That tells us this is a very resilient system. If we do the right things, it will heal.”

The Everglades are North America’s most important breeding area for wading birds, which have declined nearly 90 percent throughout the region since the early 20th century. Scientists keep a close eye on the remaining colonies as indicators of the ecosystem’s overall health.

So far this year, surveys by air, land, and water have tallied 2,861 Wood Stork nests in the Everglades Protection Area, which includes Everglades National Park and conservation areas to the north—more than double the 10-year average of 1,356 nests. They’ve also found 28,000 White Ibis nests, more than 50 percent above average, and 7,984 Great Egret nests, about 25 percent above average. As many as 18,000 White Ibis pairs have congregated at a single rookery called Alley North, a possible record for the site, says Mark Cook, a lead scientist and avian ecologist with the South Florida Water Management District who edits the annual wading bird nesting report. “I cannot describe how amazing it is to see that number of birds in one place,” he says.

With breeding still underway, it’s too early to compare those nest counts to past totals, but they’re certainly among the strongest in the two decades the district has been counting. This year will likely surpass a solid 2017, when more than 46,000 nests of seven wading bird species, including Snowy Egrets, Little Blue Herons, and Tricolored Herons, were tallied across the entire region. After several years of below-average totals, 2017 was among the best-nesting years since the blockbuster breeding year of 2009, which saw 87,564 nests.

Like so much in the Everglades, this year’s wading-bird boom is all about water. From a week of biblical downpours in June through Hurricane Irma’s ire in September, South Florida in 2017 experienced its wettest rainy season in more than eight decades. Flooding caused widespread damage, but the soggy summer also had an upside: It gave shallow wetlands a rare recharge, 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 diverting water east and west. Those drainage projects made room for South Florida farms and homes, but they also strangled the flow of water into the Everglades, robbing wading birds of wetland habitat—and food sources.

Historically, south-flowing water filled up wetlands, spurring small fish and crayfish to reproduce. As water levels gradually receded during the dry season, prey would be stranded in shallow wetlands. While that fish-in-a-barrel concentration of food isn’t so important for Great Egrets and other birds that hunt by sight, Roseate Spoonbills, Wood Storks, and White 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. Today many of those shallow wetlands never fill up, or they dry out too fast to concentrate prey.

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

The condition of those shallow wetlands also affects the timing of nesting. In some recent years, they’ve stayed dry, forcing waders to wait until deeper pools receded enough to make foraging possible. But last summer’s heavy rains, followed by this year’s gradual draw-down during the dry season, created ideal nesting conditions for waders. In Florida Bay, the estuary fed by the Everglades that lies between the mainland and the Florida Keys, Audubon’s Jerry Lorenz estimates that up to 400 pairs of Roseate Spoonbills nested beginning in November and December—months earlier than in recent years (in 2016 nesting began on February 5) and in line with their traditional breeding schedule. The striking birds also returned to mangrove island nesting sites, bucking a recent trend of colonizing areas inland, which Lorenz attributes to water levels and salinity altered by sea-level rise and Everglades diversions.

Overall, the current breeding bonanza “shows that everything is not lost,” Cook says. Restoring the system’s natural flow will create a more balanced Everglades in which wading bird success doesn’t depend on a lucky bit of weather, he adds. “We can still restore the system. This shows how rapidly things can change when we get the water right.”

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

A $16 billion state and federal restoration program encompassing 18,000 square miles of Florida ecosystems has recently begun to undo a century of damage, and several large projects to increase the volume of water flowing south are slated for the next few years. These efforts to replenish wetlands and restore hydrology patterns, experts say, could increase the abundance of wading birds beyond what we’ve seen so far this year—which is still far still below historic levels—and reset the historical timing of nesting.

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

Renewing the flow of water through the Everglades will not only boost nesting in current breeding areas, but could also draw more waders back to traditional sites, like Audubon’s Corkscrew Swamp Sanctuary. A century ago, the ornithologist and early Audubon leader Thomas Gilbert Pearson reported seeing 100,000 Wood Storks at Corkscrew, near Naples in the western Everglades. In 1966 staff counted some 6,000 nests. But today an estimated 80 percent of shallow wetlands where Corkscrew’s Wood Storks forage have been drained or filled, resulting  in unsuitable water levels. In most of the past 10 years none of the federally threatened birds have nested at the sanctuary; instead they’ve opted for coastal marshes and managed wetlands in Georgia and South Carolina.

Moisture from last summer, the rainiest on record at Corkscrew, replenished the shallow wetlands, luring the birds back: Staff have counted about 400 Wood Stork nests since December. Most seem to hold two or three chicks, and sanctuary directory Jason Lauritsen says that about half are expected to fledge. They won’t have firm numbers until they analyze digital images at the end of the breeding season, but more chicks are taking flight every day. “This essentially is our best year in a decade,” he says. “The significant thing about this is the timing of the nesting. If we’re going to recover Wood Storks long-term, we need them to nest early.”

Lauritsen says they can’t count on weather alone to keep the storks at Corkscrew. For the continued health of wading bird populations, he says, it’s essential to preserve wetlands that act as natural flood-controlling sponges—in particular, the shallow wetlands where they forage early in the nesting season. Even as state and federal agencies work toward restoring the Everglades, the Big Cypress Swamp watershed, which includes Corkscrew, lost more than 43 square miles of wetlands from 1996 to 2010, federal data show.

To help counter that trend, Corkscrew staff are actively restoring hundreds of acres of shallow wetlands and have their eyes on thousands of acres they hope to partner with the state to acquire and manage. The broader Everglades restoration work also focuses on wetland restoration; the Picayune Strand project, for example, will rehab more than 50,000 wetland acres not far from Corkscrew.

By protecting more wetlands, Audubon and other Everglades advocates will help provide wading birds with healthy habitat and plenty to eat when they return to breed in years to come. “That’s why this year is exceptionally exciting,” Lauritsen says. “It shows that, if conditions are right, they will nest, and nest successfully.” Like the future of their new Everglades home, this year’s gawky chicks are fragile, but full of promise. 

Video: Mac Stone

Air support provided by Gary Lickle in collaboration with LightHawk.

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