In 1983, a man walking in the Berkshire Hills of Massachusetts just off the Appalachian Trail saw-or at least swears he saw-a mountain lion cross his path, which was a little unsettling and even more unexpected since mountain lions hadn’t been seen in the northeastern United States since 1903, when the last one was shot in New York State.

Soon, however, sightings were being reported all over New England. A man driving a back road of Vermont saw two cubs playing at the roadside. A pair of hikers saw a mother and two cubs cross a meadow in New Hampshire. Every year there were half a dozen or more reports in similar vein, all by credible witnesses. In the late winter of 1994 a farmer in Vermont was walking across his property, taking some seed to a bird feeder, when he saw what appeared to be three mountain lions about seventy feet away. He stared dumbstruck for a minute or two-for mountain lions are swift, fierce creatures, and here were three of them looking at him with calm regard-then hightailed it to a phone and called a state wildlife biologist. The animals were gone by the time the biologist arrived, but he found some fresh scat, which he dutifully bagged up and dispatched to a U.S. Fish and Wildlife Laboratory. The lab report came back that it was indeed the scat of Felis concolor, the eastern mountain lion, also variously and respectfully known as the panther, cougar, puma, and, especially in New England, catamount.

All this was of some interest to me, for I was hiking in about the same spot as that initial mountain lion sighting. I was back on the trail with a new keenness and determination, and a new plan. I was going to hike New England, or at least as much of it as I could knock off until Katz returned in seven weeks to walk with me through Maine’s Hundred Mile Wilderness. There are almost 700 miles of gorgeously mountainous Appalachian Trail in New England-about a third of the AT’s total trail length-enough to keep me occupied till August. To that end, I had my obliging wife drive me to southwestern Massachusetts and drop me on the trail near Stockbridge for a three-day amble through the Berkshires. Thus it was that I was to be found, on a hot morning in mid-June, laboring sweatily up a steep but modest eminence called Becket Mountain, in a haze of repellent-resistant blackflies, and patting my pocket from time to time to check that my knife was still there.

I didn’t really expect to encounter a mountain lion, but only the day before I had read an article in the Boston Globe about how western mountain lions (which indubitably are not extinct) had recently taken to stalking and killing hikers and joggers in the California woods, and even the odd poor soul standing at a backyard barbecue in an apron and funny hat. It seemed a kind of omen.

It’s not entirely beyond the realm of possibility that mountain lions could have survived undetected in New England. Bobcats-admittedly much smaller creatures than mountain lions-are known to exist in considerable numbers and yet are so shy and furtive that you would never guess their existence. Many forest rangers go whole careers without seeing one. And there is certainly ample room in the eastern woods for large cats to roam undisturbed. Massachusetts alone has 250,000 acres of woodland, 100,000 of it in the comely Berkshires. From where I was now, I could, given the will and a more or less infinite supply of noodles, walk all the way to Cape chidley in northern Quebec, 1,800 miles away on the icy Labrador Sea, and scarcely ever have to leave the cover of trees. Even so, it is unlikely that a large cat could survive in sufficient numbers to breed not just in one area but evidently all over New England and escape notice for nine decades. Still, there was that scat. Whatever it was, it excreted like a mountain lion.

The most plausible explanation was that any lions out there-if lions they were-were released pets, bought in haste and later regretted. It would be just my luck, of course, to be savaged by an animal with a flea collar and a medical history. I imagined lying on my back, being extravagently ravaged, inclining my head slightly to read a dangling silver tag that said: “My name is Mr. Bojangles. If found please call Tanya and Vinny at 924- 4667.”

Like most large animals (and a good many small ones), the eastern mountain lion was wiped out because it was deemed to be a nuisance. Until the 1940s, many eastern states had well-publicized “varmint campaigns,” often run by state conservation departments, that awarded points to hunters for every predatory creature they killed, which was just about every creature there was-hawks, owls, kingfishers, eagles, and virtually any type of large mammal. West Virginia gave an annual college scholarship to the student who killed the most animals; other states freely distributed bounties and other cash rewards. Rationality didn’t often come into it. Pennsylvania one year paid out $90,000 in bounties for the killing of 130,000 owls and hawks to save the state’s farmers a slightly less than whopping $1,875 in estimated livestock losses. (It is not very often, after all, that an owl carries off a cow.)

As late as 1890, New York State paid bounties on 107 mountain lions, but within a decade they were virtually all gone. (The very last wild eastern mountain lion was killed in the Smokies in the 1920s.) The timberwolf and woodland caribou also disappeared from their last Appalachian fastnesses in the first years of this century, and the black bear very nearly followed them. In 1900, the bear population of New Hampshire-now over 3,000-had fallen to just fifty.

There is still quite a lot of life out there, but it is mostly very small. According to a wildlife census by an ecologist at the University of Illinois named V. E. Shelford, a typical ten-square-mile block of eastern American forest holds almost 300,000 mammals-220,000 mice and other small rodents, 63,500 squirrels and chipmunks, 470 deer, 30 foxes, and 5 black bears.

The real loser in the eastern forests has been the songbird. One of the most striking losses was the Carolina parakeet, a lovely, innocuous bird whose numbers in the wild were possibly exceeded only by the unbelievably numerous passenger pigeon. (When the first pilgrims came to America there were an estimated nine billion passenger pigeons-more than twice the number of all birds found in America today.) Both were hunted out of existence-the passenger pigeon for pig feed and the simple joy of blasting volumes of birds from the sky with blind ease, the Carolina parakeet because it ate farmers’ fruit and had a striking plumage that made a lovely ladies’ hat. In 1914, the last surviving members of each species died within weeks of each other in captivity.

A similar unhappy fate awaited the delightful Bachman’s warbler. Always rare, it was said to have one of the loveliest songs of all birds. For years it escaped detection, but in 1939, two birders, operating independently in different places, coincidentally saw a Bachman’s warbler within two days of each other. Both shot the birds (nice work, boys!), and that, it appears, was that for the Bachman’s warbler. But there are almost certainly others that disappeared before anyone much noticed. John James Audubon painted three species of bird-the small-headed flycatcher, the carbonated warbler, and the Blue Mountain warbler-that have not been seen by anyone since. The same is true of Townsend’s bunting, of which there is one stuffed specimen in the Smithsonian Institution in Washington.

Between the 1940s and 1980s, the populations of migratory songbirds fell by 50 percent in the eastern United States (in large part because of loss of breeding sites and other vital wintering habitats in Latin America) and by some estimates are continuing to fall by 3 percent or so a year. Seventy percent of all eastern bird species have seen population declines since the 1960s.