Back from the Brink

Not every endangered species is doomed. Thanks to tough laws, dedicated researchers, and plenty of money and effort, success stories abound

Green turtle swimming over coral reefs in Kona
Green turtle swimming over coral reefs in Kona Wikimedia Commons

On Hawaii’s big island, marine biologist George Balazs seems to know most of the turtles by name—or at least by their markings and tags. He conducts what may be one of the longest continuous monitoring of any sea reptile, an effort of 34 years, and has presided over a cultural makeover that has turned the sea turtle, once a popular menu item, into a star of a multimilliondollar tourist industry. But Balazs credits the giant reptile itself. “The honu touch your heart,” he says, using the Hawaiian word for turtle. “These turtles are their own best ambassadors.”

For decades, Hawaiians hunted the animals for their skin, which was turned into handbags, and their meat, a delicacy. “In the 1970s, a turtle was a hundred dollar bill,” says Balazs. After he witnessed fishermen unloading a boat full of live green sea turtles bound for market in 1969, he worried that the species wouldn’t breed fast enough to sustain the demand. So he made an inventory of nesting female turtles at the animals’ main breeding site: the French Frigate Shoals, an atoll about 500 miles west of Hawaii in an area that had been designated a wildlife sanctuary by President Teddy Roosevelt in 1909. In 1973, his first year of fieldwork, Balazs counted a mere 67 nesting females, not enough to compensate for the rate at which Hawaiian green sea turtles were being hunted.

Largely because of Balazs’ research and advocacy, the U.S. Fish and Wildlife Service (FWS) in 1978 classified the Hawaiian green sea turtle as threatened under the ESA. Killing a honu became a federal offense. The green sea turtle made progress, despite its slow reproductive pace: females reach sexual maturity at an average age of 25, and swim from Hawaii to their nesting grounds and back—a 1,000 mile round trip—every three or four years. (In the 1980s, an outbreak of fibropapilloma, a mysterious disease that afflicts many turtle species, dealt the animals a setback, but the disease seems to be abating.) Balazs estimates the number of nesting females has risen to over 400 annually—a sixfold increase since the early 1970s. This rebound stands in contrast to other sea turtle species, five of which—leatherback, log- gerhead, Kemp’s ridley, olive ridley and hawksbill—remain endangered in all or part of their ranges around the world.

As the honu began reappearing near several Hawaiian islands, including the BigIsland and Kauai, snorkeling tour operators, beachfront hotel owners and even wildlife art dealers recognized the enormous potential of turtle tourism. This particular “watchable wildlife,” like the boon in whale-watching tours and even programs to view wolves in Wyoming, underscores the truism that many once-hunted critters are worth more alive than dead.

On a residential stretch of beach in the Puako neighborhood on the BigIsland, Balazs and a team of high-school students from the HawaiiPreparatoryAcademy spend the day capturing, measuring and tagging turtles taken from the turquoise waters. They’ve tagged thousands of turtles over the past two decades.

Diane Campbell, who lives in the neighborhood, comes down to watch. “I love the honu,” she says. She is wearing a T-shirt with a picture of the turtle and a message: “In recent years their numbers have declined due to disease and the destruction of their native habitat.” Balazs asks if she purchased the shirt recently.

“No, it’s at least ten years old,” Campbell says. “I cheer every time I put it on.”

More Than a Symbolic Victory
Status: Threatened, awaiting removal from list
Year declared endangered: 1940
Lowest count in lower 48 states: 417 nesting pairs

In 1782, the Second Continental Congress incorporated the bald eagle into the first great seal of the United States as a symbol of “supreme power and authority.” Unlike the king’s England, where wildlife was the exclusive property of royalty, in this new nation wild animals belonged to all the people.

By the 1930s, the national symbol was in trouble. Bald eagles, once soaring over most of the country by the hundreds of thousands, had plummeted in number to an estimated 10,000 pairs by the 1950s. Hunting, land clearing and accidental poisoning (eagles often ate toxic meat set out by ranchers to kill wolves and other predators) contributed to the decline. In 1940, Congress jumped to the fore with the Bald Eagle Protection Act, which acknowledged the scientific and political reasons to conserve the distinctive whiteheaded bird with a seven-foot wingspan. “The bald eagle is no longer a mere bird of biological interest but a symbol of the American ideals of freedom,” the law states. It prohibited the killing of bald eagles for virtually any reason.

But the introduction of DDT in 1945 dealt the animal a critical blow. The pesticide, sprayed far and wide to eradicate mosquitoes and agricultural pests, crept into the food chain. Fish ate exposed bugs, eagles and other birds ate pesticidelaced fish, and the DDT ingested by the birds so thinned their eggshells that chicks couldn’t survive. By 1963, only 417 bald eagle nesting pairs were found in the lower 48.

In 1972, ten years after Rachel Carson’s Silent Spring publicized the insidious threat of DDT, the U.S. Environmental Protection Agency banned the pesticide. Still, the hunting and chemical regulations would not have been enough to revive the bald eagle. The passage of the ESA provided critical help by protecting the bird’s habitat. Other federal laws would also contribute. Efforts to decontaminate the Chesapeake Bay, prompted by the Clean Water Act, benefited the eagle by slowly reducing harmful pollutants from prime bald eagle feeding grounds.

Widespread affection for the emblematic bird also made a difference. Eagle lovers monitored nests, educated the public and campaigned to close nesting areas during the breeding season. The U.S. Fish and Wildlife Service (FWS) banned hunters from using lead shot nationwide, which can poison eagles and other raptors that scavenge waterfowl that have been struck by the shot. Meanwhile, the eagle itself adapted to living near people—even setting up nests a few miles from the U.S. Capitol.

In 1995, wildlife authorities changed the bald eagle’s status from endangered to threatened, an important moment in conservation history. Today, with about 7,678 pairs of bald eagles in the lower 48, the bird awaits a final OK to be taken off the ESA’s threatened list, a move that many anticipate will come quickly. “People want success,” says Jody Millar, Bald Eagle Monitoring Coordinator for the FWS, in Rock Island, Illinois. She says that the recovery of the beloved national symbol has generated public acceptance of conservation measures. “No government can protect a species if the public doesn’t want it.”

An Island Within an Island
Status: Endangered
Year listed: 1967
Feeding habits: Finicky

Paul banko walks along the arid slopes of the 13,796-foot-high Mauna Kea volcano on Hawaii’s Big Island. He’s searching for a yellow-crowned songbird called the palila. He hears the trilled warble that gives the bird its onomatopoeic name, but he doesn’t actually see one. “Typical Hawaii birding experience,” Banko deadpans. For nearly two decades, Banko, a U.S. Geological Survey wildlife biologist, has sought to reverse the palila’s decline by working to restore its habitat and coaxing the birds to colonize another territory. The bird, a type of Hawaiian honeycreeper, lives almost exclusively on seeds from the increasingly scarce mamane tree.

The state’s flora and fauna have long been vulnerable to habitat loss, invasive species, overharvesting and disease. In deed, Hawaii is home to a quarter of all the United States’ animals and plants listed under the ESA, with more than 300 threatened or endangered species, more than 100 candidate species and more than 1,000 species of concern. Almost half of Hawaii’s native bird species have become extinct.

Human activity has devastated Hawaiian birds and other wildlife since Polynesians first settled the islands some 1,600 years ago. Stowaway rats that leapt from their canoes preyed on birds’ nests. Several species of flightless geese, prized as food, were extinguished. Other birds were culled for their plumage, and Hawaiian kings cleared forests for agriculture. Europeans, arriving in the late 18th century, brought mosquitoes that later transmitted avian pox and malaria, against which native songbirds had little resistance. Introduced sheep, pigs, cats and cattle compacted soils, ate mamane seedlings or devoured nestlings. Ranchers cleared forests for cattle pastures. Mongooses were imported to control the rats, but because mongooses hunt during the day, when rats hide, the mongooses ate ground-nesting birds instead. The palila vanished from the islands of Kauai and Oahu probably before 1800.

Hawaii’s endangered species experience is instructive, Banko says, because the destruction and fragmentation of habitats as well as the domination of native species by invaders are the root causes of many species’ decline. “We see this as a microcosm of what’s happening on the continent in terms of watching ecological processes unravel,” he says. The process is just more obvious on a real island than on one of the ecological islands that increasingly occur on the mainland— isolated habitats surrounded by highways, strip malls and housing developments.

The palila was one of the first species to be protected under the ESA when an early version of the law passed in 1966. Still, state authorities did little until 1978, when the palila did what any red-blooded American bird would do: it sued. In Palila v. Hawaii Department of Land and Natural Resources (the first time a bird was a plaintiff in a lawsuit, which was brought by the Sierra Club Legal Defense Fund), a federal court ruled that under the ESA, the state had to prevent further damage to the bird’s habitat. In the 1990s, when the U.S. Army proposed building a road through critical palila habitat, the ESA dictated that the military pay nearly $14.6 million to fund palila restoration projects.

By then, most palila were confined to a 12-square-mile forest on the west slope of Mauna Kea, between 7,000 and 9,000 feet. This lone population of about 3,000 birds easily could have been wiped out by fire, storms or a disease that strikes mamane trees. With the military’s mitigation money,

Banko and co-workers set out to expand the palila’s existing forest and establish a new palila population On Mauna Kea’s north side. Banko and others netted palila on the west slope, equipped them with tiny radio transmitters and moved them to the north slope. Most of the birds simply flew the 12 miles home. This past March, however, the researchers relocated another 75 wild palila, and some appear to have stayed put. At the same time, Alan Lieberman, of the Zoological Society of San Diego’s Center for Reproduction of Endangered Species, along with his colleagues at Hawaii’s KeauhouBird ConservationCenter, have bred palila in captivity and released 15 of the birds in the northern habitat. Though some died or disappeared, Lieberman says, the survivors appear to be acting like wild palila, and at least one pair is mating. On Mauna Kea’s north side, Banko walks around a forest of 20-foot-high mamane mixed with an occasional koa and sandalwood tree. Over a hand-held radio, he receives a report from one of his field researchers: there are five palila in a tree half a mile away. The tree stands in the middle of what the researchers have dubbed “palila paradise,” where they’ve spotted 20 of the birds. “I think the palila will colonize this area,” Banko says, but he acknowledges it might take decades to build a community that won’t need to be supplemented with captive-bred or relocated birds. He spots a female palila flitting in and out of the mamane tree. Everybody spies her activity through binoculars. After a few minutes, it’s obvious what she is doing: building a nest.

A Clown Makes a Comeback
Status: Threatened
Year listed: 1977
Skill: Uses tools (rocks, shellfish) to obtain food

Hundreds of thousands of sea otters once ranged from Baja California to northern Alaska and across the Bering Strait to Russia and Japan. The animal was thought to have been eliminated from the California coast in the early 20th century, despite a 1911 international treaty that protected sea otters from the fur trade. In 1938, biologists made a startling announcement almost like that of the recent ivory-billed woodpecker’s rediscovery: up to several hundred animals were living near Big Sur. With that news, a rocky conservation success story began unfolding.

Over the next four decades, in the absence of hunting pressures, the sea otter population in California climbed to approximately 1,800. But the otters faced new problems, including oil spills and some commercial fishermen who considered the otters competition (they are voracious eaters) and killed them. Commercial gill net fishing, a practice akin to dropping a curtain into the water and capturing almost anything that swims by, killed an estimated 1,000 sea otters between 1973 and 1983.

The otter’s tale provides a lesson in why species protection is so urgent. Plants and animals in a particular region interact with one another in intricate and sometimes unknowable ways; the disappearance of a species can set off a cascade of problems. Take the sea otter in Alaska. Research biologist Jim Estes of the USGS Biological Resources Division suspects that overharvesting of whales in the Aleutian Islands in the 1990s prompted orcas, which eat other whales, to venture closer to shore and prey on sea lions, harbor seals and sea otters. As sea otters dwindled, one of their key foods, sea urchins, boomed. Sea urchins graze on kelp, so kelp forests declined. Without the kelp, crabs, clams, sea stars and many fish species suffered. In California, the decline of sea otters due to hunting and lost habitat had a similar outcome.

The southern sea otter of central California has been helped by the ESA and other laws, including 1980s regulations that moved gill net fishing farther offshore. In the late 1980s, a small otter population was relocated to an island off the coast to ensure a separate, distinct colony as a hedge against a calamitous oil spill or disease epidemic. Today, there are more than 2,500 California sea otters between HalfMoon Bay and Santa Barbara, and the population appears stable. Sea urchins there are returning to normal, and kelp forests are thriving.

Who’s Your Mommy?
Status: Endangered
Population low point: 21 wild birds in 1941
Surrogate parents: Puppets, costumed people, ultralight planes

One of the most audacious endangered species recovery efforts starts at the USGSPatuxent WildlifeResearchCenter in Maryland, between Baltimore and Washington, D.C. There, researchers breed whooping cranes and prepare them for life in the wild. That might sound simple, but the project uses special effects worthy of George Lucas. Even before a bird hatches, researchers subject the egg to recordings of a roaring motor, to accustom a fetal bird to the sound of its foster parent— an ultralight aircraft. Once the birds hatch, they’re fed by crane puppets, and the people working with the chicks cover themselves in shapeless white sacks to prevent the birds from growing attached to humans. As the baby whoopers grow, they are taught to follow an ultralight equipped with a puppet crane head while a costumed pilot drives the plane in circles on the ground.

When the cranes are ready for the next step, at about 6 weeks of age, biologists ship them by private jet to the Necedah Wildlife Refuge in Wisconsin. There, the chicks learn to fly along after their aircraft parents. When it’s time to migrate, the young cranes follow the ultralight to their wintering home, in Chassahowitzka National Wildlife Refuge in Florida (along the way, the plane stops at different private and public properties to allow the birds to eat and rest). “We show them the way once,” says Heather Ray, who used to work for the group that runs the crane project, Operation Migration. After that, she insists, despite their odd upbringing, “these are wild birds.”

The whooping crane, like the black-footed ferret in the Great Plains and the California condor, is inching back from the precipice of extinction. In 1941 the species vied with the ivory-billed woodpecker for the title of North America’s most endangered bird. Only 21 whooping cranes were left in the wild, the population devastated by hunters, wetlands loss and fashion (their plumes topped ladies’ hats). Conservationists were eager to revive the species, but they didn’t know where to start: nobody knew exactly where migratory whooping cranes nested. Then, in 1954, firefighters found whooping cranes at the WoodBuffaloNational Park in the Northwest Territories in Canada. Recovery efforts for this migrating bird with a seven-foot wingspan now had a multinational twist. A Canadian-American team created a new migration route for the birds from Wisconsin to Florida (there is also a nonmigratory whooping crane population, in Florida) to supplement the cranes’ historic route from Canada to Texas, reasoning that bad weather or other problems along the single route could wipe out too many cranes.

By now, the whooping crane recovery program has used virtually every trick in the conservation biologists’ toolbox: captive breeding, intensive training of nestlings, international cooperation, partnerships between government and conservation groups, habitat conservation and great gobs of public and private money.

Last July, the population hit a milestone of 338 whooping cranes in the wild, including captive-bred birds that have now made the migration without a motorized escort. Though still endangered, the species has come a long way from its double-digit nadir. “If we can save the whooping crane,” she adds, “we can save all the other species.” The achievement, she adds, is “the wildlife equivalent of putting a man on the moon.”

Safe Harbors on PrivateLand
Status: Endangered Year listed: 1970
Security measure: Pecks at pine tree bark to release pitch, which oozes down the trunk and stymies snakes

In the early 1990s, while environmentalists and loggers in the Pacific Northwest battled over the northern spotted owl, sentiment was running high in the Southeast over the red-cockaded woodpecker (RCW). The medium- sized bird nests in mature longleaf pine forests, which have been heavily logged since the 19th century. After it was listed as endangered in 1970, some private landowners from the Carolinas to Mississippi deliberately cut longleaf pine trees to prevent the bird from squatting on their land. One driver’s personalized license plate read “I eat RCWs.”

The question of what to do with endangered species on private land had long vexed wildlife managers. Some property owners have opposed species conservation efforts because of concerns that they’ll have to restrict commercial activities if an endangered species is identified on their land. The conflict over the woodpecker inspired a new approach to the problem, a cooperative agreement called SafeHarbor: if landowners agreed to help protect and restore a listed species, the federal government would waive particular ESA restrictions.

The first signatory of the agreement to save the red-cockaded woodpecker, perhaps the most successful SafeHarbor arrangement in the program’s ten years, was the Pinehurst Resort (site of the 2005 U.S. Open) in North Carolina, which agreed to replant longleaf pines and log their private forest holdings near the resort with selective-cutting rather than clear-cutting. In return, U.S. wildlife officials agreed that Pinehurst and other landowners would not be subject to increased limits on development.

The SafeHarbor agreement, like other conservation measures, didn’t succeed on its own. Biologists fostered the regrowth of longleaf pines by burning competing undergrowth. And they constructed nest boxes and set them into trunks of smaller trees to serve as suitable nesting cavities until forests matured. Today, the red-cockaded woodpecker population is an estimated 15,000.

Moral? “We’ve got to make landowners allies in species conservation,” says Colin Rowan of Environmental Defense, a group that helped forge the SafeHarbor concept. More than 320 private landowners are enrolled in the SafeHarbor program, contributing to the protection of 35 threatened and endangered species on more than three million acres.

Tinkering With Dams
Year listed: 1994

Maximum water temperature fry can withstand: 57.5ºF

Salmon runs have dropped precipitously along the PacificCoast—victims of dams, waterway diversions and riverside habitat destruction. But along the Sacramento River in California, winter chinook salmon runs have grown from a low of just 186 fish in 1994 to more than 10,000 this past winter.

In this case, the salmon’s decline can be linked to too much concrete. In 1945, Shasta Dam in Northern California shortened the length of river accessible to salmon, forcing the fish to spawn farther downstream. Next, the Red Bluff Diversion Dam, built in 1964 about 45 miles below the Shasta, near Redding, started blocking salmon from migrating up or down the river. Then, during a drought, Shasta Dam released warm water into the river in the summers of 1976 and 1977, to keep the streams flowing. The outcome for baby chinook was predictable: the fry fried.

In 1985, scientists petitioned the National Marine Fisheries Service to classify the fish as endangered. NMFS officials ruled that although the fish was decidedly in trouble, a formal listing under the ESA wasn’t necessary. An Earthjustice attorney sued. While the case was pending on appeal, in 1990, U.S. officials classified the California winter run salmon as threatened.

Yet chinook populations in the Sacramento River continued to drop, and after another petition the fish was reclassified as endangered in 1994. The ESA then mandated, among other engineering changes, that Shasta Dam operators install a device that would pump deeper—and thus colder— water into the river. The ESA listing also compelled the federal government to clean up one of its worst Superfund sites, at Iron Mountain Mine near Redding, which had been contributing to salmon deaths by leaching heavy metals into the river. All told, federal and state agencies have spent more than $200 million to revive the salmon’s winter run.

Not Glamorous, but Protected
Status: Endangered
Year listed: 1992

Number of other butterflies listed as threatened or endangered: 44

The karner blue butterfly once lived in 12 Eastern and Midwestern states and the province of Ontario, Canada. But as agriculture and development destroyed its prime habitats, including oak savanna and pine barrens, its numbers declined across its range by 99 percent or more.

The federal government declares species endangered, but subsequent recovery efforts draw on state and local agencies as well as federal ones, along with conservation organizations and private landowners. In Wisconsin, the heart of the Karner blue’s range, the entire state helped bring this fluttering species back. Today, 38 different partners participate in a sweeping conservation plan that takes into account the butterfly’s life history. When the caterpillars hatch in spring and summer, they require fields of lupine for food and shelter. So the Wisconsin Gas Companyagreed to mow grass along its power lines later in the summer than usual, to give Karner blue caterpillars time to metamorphose into butterflies and fly away. The state highway department and other partner organizations also mow late, and they leave the grass long at the end of the growing season to help butterfly eggs survive the winter. Forestry companies and other partners delay herbicide and pesticide spraying on their lands until the fall, after lupine and other plants have died. “We will lose this species if we don’t have institutionalized management,” says Cathy Carnes, endangered species coordinator with the FWS in Wisconsin

Restoration of the insect’s habitat appears to be a boon to other scarce animals that share it, such as the endangered Kirtland’s warbler (which breeds in Michigan but visits Wisconsin), the slender glass lizard, the eastern massasauga rattlesnake and the wood turtle.

To be sure, charismatic, symbolic or particularly cute endangered species often receive the lion’s share of public attention and money, but the vast majority of endangered or threatened species are plants, unpretentious animals or insects like the Karner blue. The butterfly will never stir people’s hearts quite like a bald eagle does, but its ESA listing prompted enough changes that the Karner blue stands a good chance of surviving. “We still have time to preserve what we have left,” says Carnes.

Sharing Water During a Drought
Status: Threatened
Year listed: 2002
Newly adopted habitat: Cattle watering tanks

Arizona ranchers Matt and Anna Magoffin earned an unofficial nomination to the Endangered Species Hall of Fame by hauling a thousand gallons of water per week to a stock tank on their ranch for four years, all to save a frog on its last legs.

Many Southwestern aquatic species have suffered in the past century. Invasive species have altered the desert habitat, fungal diseases have hit frogs and other amphibians, and ranching and the Sun Belt population boom have diverted water, disrupted river and stream habitats and destroyed seasonal watering holes. The Magoffins are part of a coalition called the Malpai Borderlands Group, which created a SafeHarbor agreement for the Chiricahua leopard frog after it was listed as threatened in 2002. Biologists estimate that the frogs have disappeared from 75 percent of their historic range, and today the frog population is at or near its lowest point ever. To help the frog, the Magoffin family rebuilt water tanks, put in wells, poured concrete ponds and moved tadpoles from drought-stricken pools to more reliable water sources.

Biologist Jim Rorabaugh of the FWS in Phoenix credits the Magoffins with paving the way for frog conservation on the one million acres where the Malpai Borderlands Group is active. Most of that land is public, controlled by Arizona, New Mexico, the U.S. Forest Service or the Bureau of Land Management, but much of it is owned privately by ranchers.

“We’re a long way from recovering this species,” says Rorabaugh. “But we’ve got some really good partnerships on the ground.”

Life With a Top Predator
Status: Threatened in lower 48 states, but maybe not for long Year listed: 1975
Maximum height: Seven feet when standing

“Welcome to Grizzly Country.” The sign is at the entrance to the squat, concrete building that houses the Cody district office of the Wyoming Game and Fish Department. Mark Bruscino, the agency’s bear management officer, says he’s trying to “keep the peace between people and bears.”

Grizzlies once roamed a vast swath of the Great Plains and Western states, but now occur only in isolated populations in Montana, Idaho, Washington and Wyoming. (They’re doing fine in Alaska.) By the early 1970s, hunting and development pressures caused the grizzly population in the Yellowstone area to plunge to about 150 bears, many of which were raiding trash bins in the national park. In 1975, officials classified the species as threatened in the lower 48.

Today, Yellowstone and its surrounding area, most of which is national forest land, is home to more than 600 bears, and the FWS is considering taking the grizzly off the threatened species list. It is “the wildlife recovery success story of the century,” Bruscino says. Not that it was easy. The great bear is slow to reproduce, reaching sexual maturity at 4 to 5 years of age. Females give birth to only one or two cubs every three to five years. And grizzlies require great expanses of wild country to make a living.

One important factor in the grizzly’s rebound has been teaching people how to live with bears. That means keeping the animals away from humans so rangers or others don’t relocate or shoot them. Near Cody, east of YellowstoneNational Park, an eight-foot-high bear-proof fence protects a small schoolhouse. Some ranchers take their cow carcasses to the county dump rather than leaving them to attract ursine scavengers. (The state of Wyoming has reimbursed ranchers more than $500,000 since 1995 for livestock losses.) Before a dumpster can be certified as “bear-resistant,” a 900-pound captive grizzly pounds away at a prototype filled with peanut butter and cookies. People put up electric fences around beehives (bears do love honey) and learn how to behave in a grizzly’s presence (never look them in the eye, back away slowly).

The long-term prognosis for the Yellowstone bears is cloudy. Genetic inbreeding may hamper this population’s survival. And conservationists worry that declaring the grizzly no longer threatened will open the Yellowstone area to increased oil, gas and residential development, which would fragment the grizzly’s habitat even more and hamper, if not undo, the bears’ progress.

Chris Servheen, the grizzly bear recovery coordinator for the FWS, says the bears have come back largely because people aren’t killing them as much as they used to: “The most important habitat for bears is in the human heart.”

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