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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.
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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.
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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.
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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
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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,
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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
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