Being desk-bound might seem like purgatory for a freshly minted wetlands ecologist. But Cyndy
Loftin admits that after five years of field work in one of the wildest and soggiest landscapes in
the lower 48 states--southeastern Georgia's Okefenokee Swamp--she was "ready to get
back on
dry land" and face the chore of writing her Ph.D. dissertation and articles about her research
for
various scientific journals.
An American original, the Okefenokee is one of the world's great primitive
wilderness areas and
wildlife preserves. For decades, people have used words like "dark" and
"forbidding" to describe
it--and not without justification. Perhaps that's why a lot of secrets about the swamp's ecology
remain hidden. Told that one of her colleagues had called the swamp an "inhospitable and
dangerous" place to work, Loftin, a research associate with the Florida Cooperative Fish
and
Wildlife Research Unit, laughs and says, "It depends on how badly you want to do a
study."
Was Loftin worried about getting lost in a virtually trackless world of prairies, lakes, cypress
stands and piney islands where alligators stare back at every glance? "I carried a compass
and
knew that I could go north, south, east or west and eventually hit a canoe trail," she says.
But
Loftin also vividly remembers the time when a helicopter pilot forgot where he had dropped her
off. "I knew where I was," she recalls, "and I had a radio, so I could hear the
helicopter crew
arguing about where to go." From the air, the pieces of the Okefenokee mosaic have few
hard
edges.
"You know," Loftin reflects with a touch of wistfulness, "I really miss the
place." The Okefenokee
Swamp, it seems, can get under your skin in more ways than one.
There may be larger
wetlands in North America and the world, but none are quite like the
Okefenokee. An immense bog covering 770 square miles of the Atlantic coastal plain, the swamp
sits 75 miles inland from the present Georgia shore. However, prevailing wisdom asserts that the
saucer-shaped depression, which is tilted from the northwest to the southwest, was a salty lagoon
behind a 40-mile-long sandbar until the ocean receded 250,000 years ago.
Today, the
Okefenokee lies about 100 feet above sea level and the ancient sandbar on its eastern
rim is now known as Trail Ridge. The ridge is a natural dam that confines rainfall--the source of
70 percent of the swamp's water--to the basin. There the water moves ever so slowly to the
headwaters of both the Suwannee River, which drains into the Gulf of Mexico, and the St. Mary's
River, which empties into the Atlantic. Trail Ridge also is a rich source of titanium minerals,
deposited by ocean waves and winds. Those minerals were the reason for a proposed,
controversial mining operation that became the latest threat to the swamp's integrity.
Peat
deposits as thick as 15 feet cover the Okefenokee's sand bottom, and methane gas produced
by the decay of sunken vegetation periodically propels large chunks of this compressed organic
matter to the surface of open water areas. Most of these peat mats, some as long as 100 feet, will
sink back to the bottom. However, a few of these "floating islands" rapidly undergo
succession to
shrubby greenbrier tangles and then to swamp forests populated with bald cypress, loblolly bay
and black gum trees.
But walking on one of these peat rafts, where you might sink to your
waist without warning, is an
unsettling experience. This accounts for an Indian word for the place ("Ekanfinada"
on a map
from 1790) that means "trembling earth." European families that settled on the upland
islands and
lived off the swamp in the mid-1800s pronounced it "Oak-fin-oak" rather than the
more
euphonious "Oaky-fen-oaky" one usually hears today.
The swampers, as these
pioneers were known, also left their names on such places as Mixon's
Hammock, Minnie's Lake, Craven's Island and Chesser Prairie. Note, though, that the
Okefenokee's so-called prairies are covered with a foot or more of warm tannic tea and aquatic
vegetation such as water lilies and bladderworts rather than windblown fields of bluestem grass
and purple coneflowers. A high-and-dry Dakotan would call them marshes. They cover about 8
percent of the swamp, most of which lies within the boundaries of the largest national wildlife
refuge east of the Mississippi River. In turn, most of Okefenokee Refuge, created in 1937 by
President Franklin D. Roosevelt, is designated as a wilderness area.
No surprise: Animal and
plant life abound in the Okefenokee. By latest count, the swamp hosts
234 species of birds, 49 mammals, 64 reptiles, 37 amphibians, 39 fishes and at least 621 plants.
The number of insect species is any entomologist's guess, but clearly it is huge. "The
Okefenokee
is reputed to be a place of mystery and terror," observed nature writer Franklin Russell,
"yet it is a
world of millions of singing creatures and a garden of spectacular flower displays."
The swamp's loudest voice is the basso profundo of the American alligator.
According to tales
told over jars of moonshine, gators once were so abundant that people supposedly could walk
across the swamp--25 miles east to west, 38 miles north to south--by stepping on the great
reptiles' armored backs. "No true Okefenokee man would have traveled anywhere in the
swamp
without carrying his gun and a pole shod with iron that he could use to beat back attacks on his
boat by alligators seeking to seize his dogs," Russell related.
By the early 1970s, when
Russell's classic book on the swamp was published, alligator
populations throughout the Okefenokee and across the southeastern United States had been
decimated by hide hunters to make fashionable handbags and shoes. Howard Hunt, curator of
herpetology at Zoo Atlanta, remembers that when he first visited the swamp in 1965, he saw piles
of bleached gator bones along the only road into the interior. A federal-government clampdown
put the poachers out of business, and today the refuge has a healthy number of alligators--as many
as 12,000--though presumably a lot fewer than in historic times.
The swamp's other formidable
creature is the black bear, and Hunt's research, which includes the
use of surveillance cameras, revealed that Ursus americanus is the primary predator of
Okefenokee alligator nests. A female alligator typically deposits around 30 eggs in the middle of a
four-foot-high mound of vegetation, which she scrapes together with her feet while backing in a
circle around the nest site. But her work often goes for naught.
Hunt monitored 129 nests
over a 13-year period and found that 69 percent of them were lost to
all predators during the six-week crucial incubation period. In one of his study areas, the figure
was 93 percent, the highest ever reported. In contrast, the predation rate on alligator nests in one
Florida Everglades survey was only about 7 percent.
"The Okefenokee is one of the few
places where you get lots of bears and alligators in the same
place," says Hunt. He suggests that while nest-guarding female gators will rout marauding
raccoons or otters and sometimes bluster at human intruders without attacking, they're
"reluctant
to do all-out battle with a bigger predator. Otherwise we would find alligators ripped to shreds or
bears with serious injuries."
When the intrepid scientist donned a black bear costume and approached one
alligator nest on all
fours, the female lurking nearby submerged and swam away for a considerable distance.
"They
do what's the least hazardous to their health," Hunt adds. "They can always make
another nest."
Cyndy Loftin has never prowled the prairies in a rented fur suit. Among other things, she was
always busy monitoring two dozen water-level recorders. However, her study of the swamp's
hydrology, vegetation and related refuge-management issues was not as ho-hum as it might
sound. In fact, her findings will lead to the correction of a serious mistake that was once ordained
by the U.S. Congress.
The Okefenokee is one of the best-preserved wetlands in America, but humans have
left more
than footprints. In the 1890s, a scheme to drain, log and then farm the swamp was aborted when
the money ran out after steam shovels had dug 12 miles of the Suwannee Canal. In 1909, loggers
built a railroad trestle deep into the swamp and took out 430 million board feet of cypress before
the easily accessible timber ran out.
And after wildfires in 1954-55 burned 80 percent of the
refuge along with thousands of acres of
the high-value pine plantations that surround it, Congress attempted to solve future fire problems
by ordering construction of an earthen levee--the Suwannee River Sill--"to prevent
drainage of
the Okefenokee Swamp during periods of drought." At the time no one understood that
only 20
percent of the water leaves as stream flow and 80 percent as plant evapotranspiration. Indeed,
most of the area has no perceptible water movement like the sheet flow of the Everglades to the
south.
Loftin found that in dry periods, the sill floods only 4,000 acres, or less than 1 percent
of the
swamp. Moreover, she noted, as many fires occurred after construction of the levee as before.
After all, the Okefenokee is located in one of the country's highest lightning-strike zones. In
high-water times, however, the sill impoundment covers as much as 60,000 acres and has altered
plant successional patterns on about half that area, Loftin reports. The U.S. Fish and Wildlife
Service now plans to remove water-control structures and breach the levee in order to restore the
affected area's original hydrology and vegetation.
But as Loftin emphasizes, wildfire is an
essential part of the landscape dynamic. Peat corings
show that intense fires occur every few hundred years during extended droughts, playing a major
role in reshaping the character of the swamp. For example, many present-day prairie/marsh and
open-water areas were created when fire raged through swamp forest and burned deep into the
peat. Surface fires like those of the mid-1950s set back plant succession to a lesser degree. Refuge
policy calls for extinguishing fires of less than one acre, containing larger ones in the interior and
vigorously suppressing all wildfires on the swamp perimeter that threaten private
timberlands.
The interruption of the Okefenokee's natural fire regime, Loftin says, will have
significant
short-term impact on the swamp by allowing more areas to fill in and become forest. But she
predicts that a fire intense enough to significantly change the landscape will occur within 50 years.
"Weather patterns will change, and when the peat dries out a lightning hit will cause the
whole
place to burn," she says. "But that doesn't mean all the wet forest, which accounts for
almost 60
percent of the swamp, will revert to prairie."
Meantime, conservationists can relax a bit
about the DuPont company's controversial plan to
expand its titanium mining operations on Trail Ridge. DuPont is the world's largest maker of
titanium dioxide, a white pigment used in the paper, plastics and paint industries, and the chemical
giant owns or leases 38,000 acres along the ridge. The firm's proposal to open a 30-mile-long,
3-mile-wide surface mine along- side the Okefenokee wilderness area was denounced by
Secretary of the Interior Bruce Babbitt, the National Wildlife Federation, the Georgia Wildlife
Federation and other conservation groups feared that the 50-year project would adversely affect
the swamp's hydrology.
Earlier this year, faced with an onslaught of criticism, DuPont's
embattled shareholders signed off
on a different scenario: In place of a huge strip mine, a consortium of conservationists would build
a world-class research and education facility focusing on the rare and complex Okefenokee
ecosystem and on the Native Americans who lived near the swamp or on its islands for at least
5,000 years. The success of the pact depends on finding funds to acquire land and mineral rights
from DuPont, local governments and another landowner with a financial stake in the titanium
mine.
Without that, the threat of mining could again loom on the horizon. But for the
moment, the dark
waters of the Okefenokee, which hide many secrets, are no longer rippled with trouble.
Field Editor Les Line wrote about roseate spoonbills in the April/May
issue.
NWF Priority: Protecting A
Southern Gem
The Okefenokee Swamp is the heart of the Greater Okefenokee Ecosystem, a 10-million-acre
mosaic of riparian wetlands, estuaries and uplands straddling the Georgia-Florida state line.
Because of the region's importance to wildlife, NWF and its affiliates, the Georgia Wildlife
Federation and the Florida Wildlife Federation, are seeking to protect part of the ecosystem
by
creating the North Florida Wildlife Corridor. The goal: to secure one million acres of wilderness,
connecting the Okefenokee with Florida's Osceola National Forest. "The wildlife corridor
will
benefit from environmentally compatible economic development in the surrounding
ecosystem,"
says NWF biologist Andrew Schock.
For more information, write: NWF Southeastern Natural Resource Center, 1330 West Peachtree
Street, Atlanta, Georgia 30309.