Why the fate of the Everglades is tied to the fortunes of its most stunning bird, the Roseate Spoonbill
By Mac Stone | Published: 2/1/2013
It’s hard not to look at the Roseate Spoonbill in the Everglades and think, “What happened here?” Amid the herons and cormorants, the spoonbill seems like an evolutionary hiccup, a failed experiment.
Here you have a bird that looks like it’s fresh off a float from the Mardi Gras parade, dainty pink in color, dropped in the middle of a harsh environment where violent storms are common and predators lurk at every corner. And as if it didn’t have a hard enough time dodging eagles, alligators, hurricanes, and poachers, it’s forced to enter this world by breaking out of its eggshell prison with — of all utensils — a soft blunt spoon.
It’s nothing short of a miracle that this icon of South Florida has overcome the slings and arrows of evolution and human expansion to weave its way into the complex fabric of the Everglades tapestry.
Throughout the last century, however, spoonbills have encountered obstacles far exceeding the grit of their biology. A mass extermination coupled with ever-pressing campaigns to drain their habitat has sent the roseate rollercoaster on a crash course for failure. As their populations appear to ebb and flow with the fresh-water supply that slowly surges from the north, scientists are tirelessly looking for clues as to how water-management practices can preserve the beloved birds and, in turn, save the Everglades.
The species is not confined to the Everglades, of course. It occurs in most of Florida, along the Gulf coast to Texas and Mexico, on Cuba and other Caribbean islands, and in much of Central and South America. It is one of six spoonbill species in the world and the only one native to the Western Hemisphere.
Populations in Texas and Louisiana are larger than those in Florida, but no breeding area has been more thoroughly studied than 850-square-mile Florida Bay, which lies between the southern end of the Florida mainland and the Florida Keys. It’s protected entirely by Everglades National Park and Florida Keys National Marine Sanctuary. The bay had been home base for spoonbills in Florida for centuries, but in recent decades, the pink birds have been nesting in Tampa Bay, where they now outnumber the Florida Bay population.
The bulk of Florida Bay’s spoonbill-monitoring efforts can be traced to a small office in Tavernier, Florida, where National Audubon Society scientists have been monitoring the birds for about 80 years. I had the honor of heading spoonbill research in Florida Bay during the 2011-12 nesting season under the guidance of Jerry Lorenz, state director of research for Florida Audubon, and for two years prior to that assignment, I was a field biologist in the Everglades. While I now work in South Carolina, I’m still affiliated with Audubon and remain a consultant with the spoonbill team.
Spoonbills nest in colonies on mangrove islands, frequently above standing water and beneath a dense cover of branches. The locations keep predators — and biologists — at bay. Females typically lay three or four eggs, and the parents take turns incubating the eggs for about three weeks. After hatching, it takes about six weeks for the chicks to be able to leave the nest; the parents continue to feed their young for another three weeks.
From November to March, peak breeding season in Florida Bay, my daily mission was to go on a scavenger hunt, hopping from island to island in search of pink gold. Climbing through the maze of tangled mangroves and slogging through waist-deep sediment, I would listen for the distinct trill of fuzzy chicks or the nasal bark of adult spoonbills. At the fringe of the colonies, which can include more than 400 nests of Anhingas, herons, cormorants, Brown Pelicans, and spoonbills, the sound is deafening, and the gnawing stench of chalky uric acid bites the nostrils. Beneath the canopy, guano blankets the trees and ground like a thin layer of snow.
After a season of monitoring nests, it’s hard not to feel a deep connection and responsibility for the survival of the magnificent birds. Watching a hatchling struggle to emerge from its egg and, only 40 days later, witnessing its first flight at the heels of its mother, I am filled with an almost paternal pride.
ANNUAL SPOONBILL NEST TOTALS IN FLORIDA BAY
Source: Jerry Lorenz, Florida Audubon
A crew of eight biologists travels by boat, helicopter, kayak, and on foot across the most remote sections of the southern Everglades to gather information. The result, after decades of similar work, is a comprehensive data set that shows Roseate Spoonbills aren’t merely seasonal ornaments on mangroves. Rather, they are the flying barometers for the entire ecosystem that author and activist Marjory Stoneman Douglas dubbed the River of Grass. In other words, they are the pink canaries in the Everglades coalmine.
To understand how the success of the spoonbill is intrinsically entwined with the health of the Everglades, we must start from the beginning. The earliest accounts of spoonbills in Florida Bay and the Everglades cite populations in the thousands. Pioneers of southern Florida stood in awe as radiant pink feathers blotted out the sun.
Nesting on mangrove islands throughout the bay, spoonbills sought refuge in the tangled mires with other wading birds such as Great White Herons, Reddish Egrets, and cormorants. They depended on the island oases to avoid mainland ground predators and to access their favorite foraging waters. No matter how isolated their islands were, however, the birds could not escape the demands of an opulent few.
At the turn of the 20th century, a high-fashion trend created a market for feathers that were used to adorn women’s hats; the more extravagant and bright the plumes, the higher the price. Soon, bodies of lifeless birds from all around the world were imported into large cities like New York and Chicago to find their final resting place atop the heads of wealthy women.
The Roseate Spoonbill fetched top dollar: $5 per pelt. For some poachers in the Everglades, this proved a much more lucrative business than farming or fishing — the mainstays of South Florida life. The seemingly endless populations of wading birds concentrated on small islands during the nesting season offered an irresistible revenue source. Without regulation or proper enforcement, plume hunters nearly extirpated the Roseate Spoonbill in Florida Bay, leaving only five nesting pairs by the 1930s.
Only when outcries from conservation groups echoed in the halls of Capitol Hill was legislation passed that finally banned the plume trade. With new laws in place and the founding of Everglades National Park in 1947, proper safeguards allowed spoonbills and other wading birds to begin rebuilding their populations. Over the next 30 years, Audubon’s Tavernier Science Center tracked their movements and watched as the birds’ numbers steadily climbed. When they peaked at 1,260 nesting pairs in 1979, it seemed that the resilient pink birds had staged their comeback.
Meanwhile, Florida was joining the ranks of the country’s fastest growing states, particularly in Fort Myers, Naples, Miami, and West Palm Beach. Calls to drain the Everglades to make way for agriculture and development thickened the political and economic atmosphere. Elected officials begged engineers and developers to bring Florida into the new industrial economy by relieving its citizens of the swamp and mire of the Everglades.
Just when spoonbills in Florida Bay were believed to have reached the tipping point of recovery, a major development project sent the birds spiraling back into decline.
Fresh-water flow within the Everglades watershed starts at Lake Okeechobee and extends south to Florida Bay. It is the lifeblood that sustains the wetland. The 100-mile-long and 60-mile-wide sheet flow has defined the ecosystem for thousands of years. At the end of the line, where the tannin-stained fresh water meets the emerald waters of the Gulf of Mexico and Atlantic Ocean, a vast estuary is formed, providing a nutrient-rich habitat for all manner of reptiles, birds, mammals, and gamefish.
Historically, South Florida’s ecology was built upon the foundation of two distinct seasons: wet and dry. A predictable shift in rainfall starts in May or June, and heavy rains last until November, inundating the cypress sloughs and sawgrass prairies. During the winter, or dry season, rains are sparse, and water levels in the Everglades decline steadily, leaving isolated pockets of water and concentrated fish. Every plant and animal species in the watershed came to depend on the inevitable flux, but they weren’t prepared when the flow came to a trickle.
As South Florida drained off sections of the Everglades for agriculture and development, the fresh water was diverted into the cities and excess water was dumped into coastal regions east and west of the historic watershed. In 1984, the completion of the South Dade Conveyance System — a series of canals constructed to meet agricultural water-supply needs, control flooding, and mitigate saltwater intrusion — dealt a final blow to the estuary, starving Florida Bay of nearly two-thirds of its fresh water. The result: The bay had too much salt, and other wetlands were too dry.
The bay’s spoonbill population went into freefall; in 1984, just five years after it had peaked, biologists counted only about 440 nesting pairs.
Not all the denizens of the Everglades responded to the shift as acutely as the spoonbill. By all accounts, Great White Heron and various egret populations seem to be healthy. So why, then, is the spoonbill having a harder time adapting to the changing hydrology of the region? The answer, scientists believe, lies in the bird’s biology, along with a specific set of abiotic and biotic requirements that the River of Grass has filled for thousands of years, until now.
Unlike herons and egrets, spoonbills cannot pierce their prey with their beaks. Instead, they use their bill to create small whirlpools in the water column, similar to those created by an oar moving through water. A back-and-forth motion causes small fishes and crustaceans to be swept to the birds’ beaks, which close with lightning speed the instant they touch prey. The feeding method is called tactilocation and requires the bird to expend a significant amount of energy. For this reason, many spoonbills can be found foraging in tidal areas where water levels drop throughout the day, revealing densely populated pools of prey that give the birds the maximum reward for their efforts.
During the nesting season, November to March, adults must be able to find enough food to satisfy the high energetic demands of their rapidly growing chicks. Tidal timetables shift throughout the month, and since they reach appropriate levels only during small windows of the day, they do not prove sustainable sources of food for a nest of hungry chicks. Thus, spoonbills, along with many other wading birds, have historically timed their nesting with the dry season. In doing so, they personify the quintessential relationship between seasonal water flow and available prey.
Hoping for a comeback
Just as the arctic has its polar bear and the Congo its gorilla, the iconic face of the River of Grass has become the Roseate Spoonbill. Tavernier Science Center biologists use it as an indicator species to guide our research. Our data help influence water-management plans and provide the scientific foundation for Everglades restoration efforts.
At each colony, we count nest production and success rates over the course of the breeding season. Two years ago, in 2010-11, we found only 87 nests in Florida Bay, the smallest total since the 1950s. No one knows why the numbers dropped so low, but we hope that the spoonbill, aided by comprehensive restoration efforts, can stage another comeback.
Already, state and federal governments are implementing plans and spending billions of dollars to return fresh water to the watershed, and in the 2011-12 breeding season, the birds surprised us yet again. We tallied 350 nests, an encouraging reminder that the spoonbill, and thus the Everglades, is anything but fragile.
HOTSPOTS FOR PINK BIRDS
Visitors to Everglades National Park have the greatest chance of seeing Roseate Spoonbills during the nesting months of January through March. Popular foraging grounds include Mrazek Pond, Eco Pond, and Snake Bight.
Author Mac Stone recommends camping at the Flamingo Marina and waking up early to look for birds foraging on tidal mudflats of Florida Bay or in Eco Pond, which is within walking distance of the campground.
In the Tampa area, look for them at Upper Tampa Bay Park near Oldsmar and at Fort De Soto County Park. On the Gulf coast, J.N. “Ding” Darling National Wildlife Refuge and Carl Johnson State Park are good spots.
In Texas, Smith Oaks Bird Sanctuary in High Island is a superb place to watch nesting spoonbills and other wading birds.
Mac Stone is the executive director of Naturaland Trust in Greenville, South Carolina. Previously he served as a research biologist with Audubon in Tavernier, Florida. Stone is a professional nature photographer, and he has also worked with conservation initiatives in Ecuador and Honduras.