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APRIL / MAY 2016 The Quest TO SAVE A Rare Bird GOING TO GREAT HEIGHTS FOR SWALLOW-TAILED KITES INSIDE AMAZON RESTORATION RAPID-RESPONSE SCIENCE KID-SIZED ECO ADVENTURES A Safe Place > By GINGER STRAND > Photographs by MAC STONE to SOCIAL BIRDS: Thousands of swallow-tailed kites roost atop cypress trees at a ranch in southern Florida. Land As researchers finally start to understand the rare and enigmatic swallow-tailed kite, they must respond to a startling discovery: Climate change is eroding the bird’s habitat. M MARIA WHITEHEAD YANKS HER FEET OUT OF THE water as something crashes into Bull Creek next to the boat. Seconds later, a 10-foot-long alligator surfaces a few yards away. As the prehistoric reptile glides off, leaving a sinuous wake in the tannin-brown river, Whitehead casually retrieves her binoculars and goes back to watching a nest of swallow-tailed kites near the top of a soaring pine. A project director for The Nature Conservancy in the South Carolina Lowcountry, Whitehead seems unfazed by nearly losing a toe on the job. So does Craig Sasser, manager of the Waccamaw National Wildlife Refuge. Wading into primeval cypress swamps, scaling 100-foot pine trees, paddling up tidal rivers through clouds of insects in tripledigit heat: These are all part of researching swallow-tailed kites, a spectacular but poorly understood raptor. Swallow-tailed kites are built like gliders, with huge wings and small, streamlined bodies. They rarely flap their wings; instead, they soar effortlessly, changing course with minute adjustments of their distinctive forked tails. They feed on the wing, snatching dragonflies and other insects out of the sky. Watching a swallow-tailed kite in flight is to be entranced. Even the Peterson Field Guide seems almost effusive about the bird, calling it “a sleek, elegant, black-andwhite hawk that flies with incomparable grace.” But admiration alone is not driving the urge to learn more about these rare birds. Subject to a variety of pressures, the kites have already undergone a historic population crash. Now, new threats are emerging that require land managers not only to understand the birds better but also to change their conservation approaches to preserving the near-coastal habitats that sustain them. 36 NAT URE CON SER VAN CY A PR IL / MAY 2016 Built like gliders, with huge wings and small bodies, they soar effortlessly. SWALLOW-TAILED KITES once nested in 21 states. Records from the 1800s show nesting pairs as far up the Mississippi Valley as Minnesota and Wisconsin. Then the population underwent a sudden decline. By 1940, the kite’s range had shrunk to seven states, from South Carolina to Texas—and the reason was unclear. Nor did anyone know how many birds remained or where exactly they flew when they migrated south. “The birds are really hard to understand because they’re hard to put your hands on,” Whitehead says. Finding their nests—well-hidden in the tops of pines—is difficult. Catching birds to tag with radio collars MEAL ON THE GO is tricky. Satellite tracking A swallow-tailed kite was impossible until recently, snatches an insect. Kites differ from when transmitters got small most raptors in that and light enough to be affixed they eat during flight, to the birds without hindering using their talons to catch prey and pass them. But the more researchit to their beaks in ers have learned about kites, midair. The bird’s distinctive tail makes the more concerned they have flight control possible become. The species is now during these complicated maneuvers. listed as endangered in South Carolina, although it is not on the federal list. “By definition they’re a little more vulnerable than some other species,” says Jim Elliott, founder and executive director of South Carolina’s Center for Birds of Prey, which maintains a database of swallow-tailed kite sightings. CO NTI NUE D O N PAGE 42 “The birds are really hard to understand because they’re hard to put your hands on.” UP AND AWAY The species’ nesting habits have always made the swallowtailed kite difficult to study. To observe these aloof birds, researchers must come to them. Ecologist Gina Kent climbs a loblolly pine that hosted a nest the previous year. 38 NAT URE CON SER VAN CY A PR IL / MAY 2016 N AT URE .ORG/MAGA Z I NE 39 LOST IN TRANSITION Freshwater wetlands are vulnerable to changes in salinity caused by higher tides, sealevel rise, and industrial and agricultural water use. Clockwise from top left: A Georgia saltwater marsh at low tide shows the influence of high salinity; a dead cypress forest marks the arrival of saltwater in South Carolina’s Sampit River; a paper mill draws freshwater from the Sampit River for its treatment processes; and, as freshwater lowland forests die back, they transition into saltwater marshes. 40 NAT URE CON SER VAN CY A PR IL / MAY 2016 N AT URE .ORG/MAGA Z I NE 41 i ipp iss iss M N.C. Ark. S.C. Miss. Texas 0 Ga. La. Winyah Bay Gainesville N 0 Ala. Gu l f of M ex i c o Fla. 300 mi 300 km CURRENT RANGE: This map shows an estimate of the swallow-tailed kite’s distribution. The bird’s range shrank due to a number of factors, including habitat loss to agriculture, logging and dams. CO N T IN U E D F RO M PAGE 36 A number of factors contribute to that vulnerability: The birds do not reach breeding age for three to four years, and females do not breed every year. Nesting adults and their young are subject to predation by great horned owls. They have high mortality on their migration between the southern United States and southern Brazil—especially in the spring, when they fly north across the Gulf of Mexico and can be swept off course by storms. And there just aren’t very many of them. Past estimates have guessed that there might be only a few thousand breeding pairs left in the country, scattered from South Carolina to Texas. Then there’s habitat loss. Cypress swamps and other freshwater forested wetlands where the birds nest have been dwindling for centuries. Since the 1700s, about half the nation’s wetlands have disappeared, threatened by agriculture, logging, dams, dredging and invasive species, as well as natural disturbances like hurricanes. The rate of wetlands loss has wavered, but it hasn’t stopped: A 2011 U.S. Fish and Wildlife Service report found that wetland losses were outdistancing gains, especially in freshwater forested wetlands. Such concerns brought a group of researchers together in the 1990s to study kites. The multistate Swallow-Tailed Kite Conservation Alliance has more than 30 partners from an alphabet soup of state and federal natural-resources agencies, timber companies and nonprofits, including the 42 NAT URE CON SER VAN CY A PR IL / MAY 2016 See One? Report It. If you see a swallow-tailed kite—or kites—researchers want to know about it. The Center for Birds of Prey, located in Awendaw, South Carolina, manages a citizen science database that logs sightings of swallow-tailed kites across their entire range. Researchers have used the center’s data to help map nesting and roosting areas, to establish target areas for habitat conservation and to engage landowners in best practices for kite-friendly land management. Their website includes information about the birds, such as locations of large foraging aggregations, extreme migration dates and diet data. The website guides you through a series of questions about the location, number and activities of the bird or birds sighted. To report sightings, go to www.thecenterforbirdsofprey.org. ONLINE: See more photos of swallow-tailed kites at nature.org/kites. Conservancy and Audubon. Over the past couple of decades, the group’s efforts have significantly expanded the understanding of swallow-tailed kites. One thing that has become clearer is how social the birds are—a rarity for raptors. About an hour after her gator encounter, Whitehead spots a large group of kites foraging over the cypress swamp. Wheeling acrobatically, they are all the more striking for their numbers. “A social raptor—it doesn’t even sound possible,” Whitehead says. “But at every phase of the annual cycle, they’re showing social behavior.” Kites forage in groups. They nest in “neighborhoods” and roost in groups ranging from dozens to more than one thousand prior to migrating. This, too, makes them vulnerable, because being social ties large groups of them to a single place. If the places where they forage, nest and roost are not protected, the population could decline further. However, preserving habitat for kites is not as simple as figuring out where the birds are roosting right now. It’s also necessary to determine where they could thrive in the future. THE DAY AFTER HER RUN-IN WITH THE ALLIGATOR in South Carolina, Whitehead is unloading kayaks at a Black River boat landing when a man in a truck drives up. “I’ve seen five of those birds,” he says. Whitehead doesn’t need to ask what he means, as all the local boat landings have signs depicting a swallow-tailed kite and asking, “Have you seen this bird?” Sightings are logged in a database managed by the Center for Birds of Prey, an alliance partner. Whitehead is pleased: Citizen science can help record not just current species range but how it’s changing. She smiles as the man rhapsodizes about kites, and then asks if any might be nesting on his land. He allows as how they might, and tells her, before driving off, that “they’re good luck.” STUDYING THE KITE MAP: © MAPPING SPECIALISTS, LTD. Breeding Range of the Swallow-tailed Kite Prior to 1900 Present day Clockwise from top: The Conservancy’s Maria Whitehead treks through cypress swamps in South Carolina’s Black River Preserve. Kite expert Ken Meyer conducts an aerial nest count in Florida. Clemson University scientists Jamie Duberstein and William Connor record salinity intrusion and study foliage samples along the Sampit River. N AT URE .ORG/MAGA Z I NE 43 Property owners like him are potential allies for Whitehead in her quest to preserve kite habitat. She works throughout Winyah Bay and its tributaries, the Waccamaw, PeeDee and Black rivers. In South Carolina, the Conservancy and its partners—including many local landowners—have protected more than 1 million acres of current and potential habitat in the coastal plain. The protected acres include those with conservation easements and preserves like the Waccamaw National Wildlife Refuge, which may have the highest density of nesting swallow-tailed kites in the state. But now a new peril looms: salinity intrusion linked to climate change. As sea levels rise, ocean tides push the “salt wedge” farther inland. This is the zone where saltwater pushes upstream in a wedge under the freshwater flowing out to sea. On South Carolina’s Sampit River, acres of dead cypress trees testify to salt’s creep upriver. Models show large swaths of freshwater cypress swamp being replaced by the spartina grass of a salt marsh. “We put the best science we had behind the creation of the wildlife refuge,” Sasser says of the nearly 20-year-old Waccamaw, “but we had no idea about sea-level rise.” The threat was starting to be understood at the time, but its effects in the low-lying freshwater swamps were yet to be seen. The Conservancy and Waccamaw National Wildlife Refuge are now working with the U.S. Geological Survey and university partners to better understand the habitat transition that’s under way. As this new understanding emerges, conservation strategy is also changing. “Thousands of acres of protected kite nesting habitat will be the first to transition to brackish marsh,” Whitehead says. “To protect the future of kites, we’re prioritizing permanent protection of freshwater forested wetlands that are upstream of the advancing salt wedge.” In other words, we have to target the areas kites need even before they need them. On the Black River, hundreds of acres of future habitat have been protected through conservation easements. And recently, the Conservancy partnered with the town of Conway, South Carolina, to expand its recreational corridor along the Waccamaw refuge while also adding more upstream habitat to the refuge itself. “When possible, we’re protecting upstream freshwater forests that are already occupied by nesting kites,” Whitehead says. “The bird’s unwavering attachment to place takes some of the guesswork out of where kites might be in the future.” “THEY KEEP COMING BACK TO THE SAME PLACES every year,” Ken Meyer says from the front seat of a Cessna as it taxis through the predawn gloom in Clewiston, a small town near Florida’s Lake Okeechobee. “In a rapidly changing world, that’s a blessing and a curse.” Executive director of the Avian Research and Conservation Institute, based in Gainesville, Florida, Meyer is another member of the Swal- low-Tailed Kite Conservation Alliance. He has been studying the birds for more than 25 years. Meyer conducts annual roost counts and tracks them by radio and satellite. Now he’s putting the data to use. Swallow-tailed kites roost en masse before migrating— and the large majority of them, Meyer estimates, do so in Florida. It’s a crucial time for them as they load up on calories for an exhausting 5,000-mile flight across the Gulf of Mexico FUTURE FORWARD and down to the tropical forests Swallow-tailed kite chicks, of southern Brazil. But here in between 2 and 3 weeks Florida, their favored habitat old, sit atop their nest in a Florida loblolly pine. is threatened—in this case, by Adults choose the tallest development. trees in the canopy to build their nests. ConMeyer’s aerial map is studded servation strategies are with red dots showing swallowshifting as state, federal and private landowners tailed kite roost sites. At the are coordinating with largest cluster, the trees are dotresearchers to ensure habited with so many white birds, it tat is protected for future generations of these kites. looks as though snow has fallen. The pilot circles high enough to avoid disturbing the birds while Meyer, leaning out the plane window, shoots photographs. The next day, Gina Kent, a research ecologist for the Avian Research and Conservation Institute, will use the photos to count the birds, getting a rough estimate of population. This is the next phase of kite conservation. Armed with their understanding of the species’ habitat needs, Kent and Meyer are now working to reshape the birds’ behaviors. They place decoy birds in trees on protected land to encourage kites to roost there. They build swallow-tailed kite nests—using plastic chicken wire, zip ties, Spanish moss and a woolly lichen called old man’s beard— and Kent ascends the tall trees to place them on wildlife preserves to attract nesting kites. But encouraging the birds onto protected land requires that there be protected land in the first place. Alliance members are developing management guidelines to help timber companies provide better kite habitat on their lands. And, like Whitehead and Sasser in South Carolina, they hope their data can help identify new areas for preservation, whether through purchase or conservation easements. It’s all part of the larger effort to protect these rare birds, not only now but in the future as well. “We can learn everything about the birds,” Meyer says, “but if we don’t translate that into protected land, it’s no good.” Editor’s note: Photography for this article was gathered during the normal course of annual swallow-tailed kite research. The scientists time their activities around nesting and roosting periods to minimize disturbance to the birds. N AT URE .ORG/MAGA Z I NE 45 backstory SUSPENDED IN AIR: Mac Stone photographs ecologist Gina Kent as they climb pine trees in Florida. Pass oN Your baCa NaTioNaL WiLdLife refuge © NiCk haLL va L u e s Reaching New Heights ASSIGNED TO PHOTOGRAPH RESEARCHERS STUDYING SWALLOW-TAILED KITES, 64 NAT URE CON SER VAN CY A PR IL / MAY 2016 Leave a lasting legacy for conservation. © DREW FULTON Mac Stone had to work creatively to capture compelling images of the birds without disturbing them (see “A Safe Place to Land,” page 34). “That’s the fun part.” Stone teamed up with biologists to rig cameras 90 feet up 100-foot trees to get close-up shots of the birds. From a distance, he flew in a plane while photographing a researcher conducting aerial surveys of the birds. He even asked an arborist to teach him how to climb trees in a way that would disturb swallowtails as little as possible: “Methodically,” he says, “and quickly.” He explains: “You take a crossbow—like a big slingshot—and you throw your line up” over a branch. “You have to climb to the top of your line and then you have to free-climb to the top. As many trees as I’ve climbed, it’s still pretty nerve-racking.” With the exception of one dropped—and subsequently smashed—piece of gear, it all worked out. “That’s part of the storytelling,” he says, “trying to take the reader into the story in as many creative ways as possible.” Making a bequest to The Nature Conservancy is a simple way to protect the places you value. You can name the Conservancy as a beneficiary of your will, trust, retirement plan, life insurance policy or financial accounts. Anyone can make a bequest and no amount is too small. For more information: (877) 812-3698 | [email protected] | nature.org/bequestad The NaTure CoNservaNCy CaNNoT reNder Tax or LegaL adviCe. PLease CoNsuLT your fiNaNCiaL advisor before makiNg a gifT. Phovv160401ZbQbCxx