“No woodpeckers,” read the real estate listing. “Lovely waterfront lot on Shadow Lake. . . . Septic evaluation being applied for.” “Oversized lot,” read another, “not in woodpecker-affected area.” When news had spread around Boiling Spring Lakes in 2006 that the Fish and Wildlife Service was concerned about the effects of rapid development on the red-cockaded woodpecker, residents rushed to City Hall, clamoring for permits to fell the mature pines on their property. Within weeks, thousands of mature longleaf pines in this coastal North Carolina town had been reduced to bark and sawdust. Newspapers reported that the run on chainsaws...

A small, ghostly fish looked out from a pool of ink, beside it a half-completed dam. This is my earliest memory of the Endangered Species Act: a front-page article in the New York Daily News circa 1977. CBS News reported it as a mismatched prizefight: “In this corner, weighing 156,000 tons, the source when completed . . . of enough electricity to power a small town, the Tennessee Valley Authority’s mighty Tellico Dam. And in this corner, weighing less than one half ounce, measuring two-and-one-half inches, the snail darter, a contender with high hopes. . . . The snail darter...

On March 11, 1967, the Department of the Interior released an official list of fish and wildlife threatened with extinction in the United States, the first wide-scale effort to address the extermination of native species. Seventy-eight animals, all vertebrates, made the short list. There were 14 mammals, including the black-footed ferret and the Florida panther. There were 36 birds, among them icons such as the southern bald eagle, the whooping crane, and the ivory-billed woodpecker (not seen since 1944). There were 3 reptiles (the American alligator, the blunt-nosed leopard lizard, and the San Francisco garter snake), 2 salamanders, and a...

We mustered at the Comfort Inn in Southport, North Carolina, at 5 a.m. US Fish and Wildlife Service biologists John Hammond and John Ellis were dressed in camouflage Gore-Tex jackets. Patty Matteson, in charge of public relations at the Service, was in her uniform; I had heard that some of the local residents considered the flying duck and leaping fish logo to be crosshairs. The fight between the local residents, armed with chainsaws, and the endangered red-cockaded woodpecker had made national news.

The woman behind the motel desk blurted out, “Are you all working with the woodpeckers?”

Matteson flinched slightly....

By the end of the 1960s, the geographic and taxonomic limitations of the government’s earliest lists of species in trouble were becoming obvious. No invertebrates, no pelagic species, such as deep-sea fishes or cetaceans, were included, and no animals outside the borders of the United States. The international fur trade killed cheetahs, jaguars, and leopards for spotted coats imported into this country. The great whales were almost gone. Whaling nations were even busy downsizing their harpoons: the explosive grenades developed for the enormous fins and blues could render unusable the relatively diminutive minke whale, the last species that was still...

The first species to be added to the original list were a bunch of kangaroos. No one was going to kick up a fuss over the listings, which did little more than prohibit the import of red and gray kangaroos from Australia. The head of the service at the time, an agency insider named Lynn Greenwalt, was determined to keep a low profile. In 1975, a handful of relatively uncontroversial species were put on the list, including the grizzly bears of the Lower 48 (dropped from the list in 1969 because they were common in Alaska); the American crocodile, long...

In his treatise on self-regulation in animals and plants, Carl Linnaeus praised the economy of nature. As he saw it, the epitome of wealth, at the root of the science of economics, was the domestication of new plants, such as foreign spices and teas. David Hume, a contemporary of Linnaeus, regarded economic processes as part of nature. Goethe claimed that “nature was the perfect economy.” It was a common seventeenth-and eighteenth-century view: economic relationships were seen as a reflection of the natural world. Even Adam Smith had a keen and long-standing interest in natural history.

“Wealth was equated with the...

Here’s how it was supposed to work: List a species. Come up with a plan to remove threats to its existence. Maybe stop the hunting or get rid of the pesticides. Protect it, preferably on public land. Let the species recover. Delist it. Move on.

If only.

Some species have indeed done very well under this type of protection. Alligator mississipiensis, a member of the Class of ’67, was a textbook case. The soft and pliable belly skins first became fashionable in Europe during the mid-nineteenth century. In the next hundred years, more than ten million alligators were killed for...

On June 30, 1954, a solar eclipse darkened the skies in northern Canada. A fire patrol in the air that day recorded that it spotted on the boreal plains of the Northwest Territories a pair of large white birds with a smaller tawny one. The sighting was unusual for that part of Canada, and word got out to ornithologists.

Robert Allen, the National Audubon Society’s first director of research, had spent more than two years in the field, hoping to make just such an observation. In 1945, he had been assigned to gather sufficient scientific knowledge to save the highly...

The Florida panther was in a desperate state. Its habitat was shrinking, and highway deaths were commonplace. After a recovery plan was drawn up in 1981, the Florida Fish and Wildlife Conservation Commission began to capture cats for radio telemetry. They found fewer than 25. Of these, only about a dozen lived in protected areas; the rest were on private lands, mostly cattle ranches on the northern edge of what was left of the big cat’s range. The remaining panthers looked closely related, sporting the kinked tails and cowlicks considered signs of inbreeding. More disturbing, more than 80 percent of...

The days were for working, the nights for driving. I traveled several hours west on 211 from Boiling Spring Lakes in the dark, leaving the coast behind for the Sandhills. In the 1990s, this region had had the second-largest population of red-cockaded woodpeckers in the country, many on private lands. Pine harvest and development were cutting off bird clusters from one another, and the rise of hardwoods was reducing the open longleaf pine habitat that the birds needed to nest and forage. The role of private landowners in these changes was especially worrisome. According to one study, up to thirteen...

The heart of the world lay open, rippling with sunlight. Rick McIntyre and I sat among elk bones, overlooking the confluence of the Lamar River and Soda Butte Creek. It was June, and McIntyre was on a folding chair, long legs outstretched beneath a tripod that held his spotting scope, the valley spread out in front of us like an open textbook. On the right bulged Specimen Ridge, snow snaking down the northern valleys, with white-capped Mount Norris on the left. Big sage covered the hillsides like an old pilled sweater. Down the center, swollen with snowmelt, the Lamar...

I remember exactly where I was on hearing that the Bush administration was going to list the polar bear—I was in my office at the Gund Institute for Ecological Economics working on a paper about whales. It was such a stunning development. The polar bear had been proposed for listing in 2005, but the Fish and Wildlife Service had dragged its feet for almost three years, coming to a decision only under court order. It hadn’t been an easy battle: the administration, which had resisted most forms of regulation in general, had in particular fought the listing of species....

I stood on the bow of the Nereid, a 27-foot research vessel. With no whales in sight on the choppy sea, my mind would wander to what the Gulf of Maine would have been like five hundred years ago, before commercial whaling began. Hundreds of right whales were probably feeding on minute copepods, leaving their bushy V-shaped blows at the surface. There would have been fin-backs, humpbacks, minkes—and maybe, just maybe, an occasional gray. The disappearance of the gray whale from the Atlantic remains a mystery. Was it hunted to extinction? Had it already disappeared before humans took to...

Dutchess County, New York, about ten p.m. I had been told that the entrance to the Institute for Ecosystem Studies in Millbrook had a clear sign. But as I drove up and down the country road, my headlights shining through the tunnel of trees, I couldn’t find it. There was the occasional flash of a firefly. The blushing crescent moon revealed a few stately homes.

Something jumped out in front of me at a twist in the road. I slammed on the brakes. A tawny young stag, a two-pointer, I think, bounded over a lapsed stonewall, its tail a white...

One Saturday morning, I rummaged through my daughter’s room, trying to distract her with a tennis ball and a baseball cap way too big for her. There were stuffed triangles and cubes, a rattle, and a toy fashioned from a plastic water bottle and swizzle sticks from her native Vietnam. Ngan (pronounced like the element, neon) had a couple of imaginary beings, a blue Cookie Monster, an odd catlike teething ring from Thai Air. But most of her toys came with an evolutionary backstory. I sorted her toy chest phylogenetically.

If we were living at the end of the Age...

Clearcut a forest, kill off a coral reef, and you destroy a medicine chest. That’s one of the longest-standing arguments for preserving biodiversity: saving species and genetic lineages protects chemical diversity. Three-quarters of all drugs for infectious diseases were discovered in nature. The African liana Anistrocladus produces michelamine B, a compound used to fight HIV. Many antiviral agents are derived from two compounds, spongouridine and spongothymidine, isolated from marine sponges collected off the Florida Keys and the Bahamas in the 1950s. Sixty percent of the anticancer drugs on the market come from natural sources, among them a compound produced by...

The second driest year on record had just ended at Lake Lanier in Georgia. Bright red mud and orange sand surrounded what water was left, like lips puckered to suck up the rest. Here and there, sailboats listed high and dry. The public boat ramps dropped off like concrete cliffs above murky green water, the three-dollar entrance fee suspended, a tollbooth covered by a black plastic bag. Abandoned in the mud, floating docks struck odd cubist angles, as if the reservoir were just a mirage, though some home-owners had built temporary docks whose new sections snaked toward the receding waterline....

At the edge of the pine forest, I stood at what had long been considered the only breeding pond of the Mississippi gopher frog. As we walked the drift fence, a foot-high corral made of roof flashing, Mike Sisson told me the frogs had moved into the ephemeral pond a couple of weeks earlier. Now we were looking for adults heading out of it.

Sisson retrieved one from one of the plastic bucket traps lining the fence. By the light of his headlamp, he showed me the marbled underbelly typical of the gopher frog, Rana sevasa. It had high ridges...

“There Is No Ivory Bill” is scrawled in black grease pencil across one of the signs at the Dagmar wildlife area in northeast Arkansas. A downy woodpecker called as I read about its history.

In the early 1940s, the Chicago Mill and Lumber Company began to cut down one of the last remaining stands of primeval bottomland in Louisiana—the Singer Tract, once owned by the sewing machine company—land that Jim Tanner, a Cornell graduate student who had studied the ivory-billed woodpecker as part of his dissertation, considered the last hope for saving the species. The National Audubon Society’s...

In hindsight, I should have known better. But, after all the places I had visited in pursuit of endangered species, I wanted to end the book with one close to home—one I could see on foot. The Indiana bat was in the Class of ’67—at risk, at least in part, because it hibernated in karst caves and abandoned mines, where it was subject to vandalism and disturbance. My home in Vermont was at the very northern edge of its range; in 2008, about three hundred Indiana bats were found in a dead elm three-and-a-half miles up the road....