In the gathering darkness of a September evening, a dozen people stand on a raised wooden walkway that stretches 200 feet along Fish Creek, a swift-flowing, remarkably clear stream in Southeast Alaska. Afternoon drizzle has turned to steady, chilly rain, and the people—tourists, all—huddle together under the boughs of a Sitka spruce. Some rock back and forth, hands deep in the pockets of their parkas. Others lean forward to peer through zoom lenses. Fat droplets pelt against aggregated Gore-Tex, creating a hollow staccato against the even murmur of the stream.

Suddenly, a splash. Downstream, just where the creek begins to twist out of view, a dark shape appears behind a scraggly willow. One of the tourists spots it, utters an imperative whisper. Cameras spin around. The shape emerges fully from around the bend and turns broadside to the audience. Even in the soggy distance, there’s no mistaking it—a brown bear (much too big to be a black), in silhouette, head down, moving upstream. The bear plods onward, closer and closer, raising whitewater with each swing of his forelegs. Five minutes later, he’s adjacent to the viewing platform. The adrenaline rush is palpable. His mouth is open, tongue hanging like a dog’s as he scans the water for the last of what has been a prodigious chum salmon run. His left eye glints with each camera flash. Then two more bears emerge from the underbrush. Then three É then four. A sow with two adolescent cubs rears up against the platform’s sturdy walls and snorts twice at a woman with a camcorder. Otherwise the animals seem oblivious to the people.

Darkness falls, the bears shamble off. So do the tourists, back to the parking lot where they left their rented cars and mobile homes. “Incredible,” one man says to his wife as they leave, and then he repeats the word. Another couple stops to chat with two Tongass National Forest rangers. The rangers have been watching the bears, and watching the people watching the bears, with mild interest. The couple thank the employees profusely, as if they have personally conjured the bears from the murk. The rangers nod amiably.

Bear season is almost over. The tourists are like the blotched salmon in the stream—hangers-on, a hint of the teeming crowds of a month earlier. More than 40,000 people have traveled here this summer to see the dozen or so brown bears that live near Fish Creek. A decade ago, virtually the only visitors were locals from the tiny towns of Hyder, Alaska, and Stewart, British Columbia, a few miles down the road.

Soon the salmon will be gone for the season. So will the bears. So will the tourists.

Alaska. A generation ago, the name connoted an almost mythical place—a state of the union, to be sure, but so remote, so wild, so full of ice and mountains and bears and wolves that few could expect to experience it outside the pages of National Geographic or the tales of Jack London. Today Alaska remains the wildest place in the nation—easily so—but it would be a mistake to label many parts of it remote. Nearly 1.5 million people visited the state in 2001, roughly twice as many as in 1990 and three times as many as in 1980. That’s 2.5 people for every Alaska resident. They don’t come for five-star meals or stage shows. They come for the scenery and the wildlife—to catch, to shoot or, as is increasingly the case, simply to look.

Most visitors to Alaska limit their stay to the temperate southern fringe of the state, a 1,200-mile arc of islands and channels that drapes over the top of the Gulf of Alaska and encompasses the two largest national forests in the United States, the Tongass and the Chugach. There, with a little planning and more than a little money, you can watch wild grizzlies chasing salmon. Or you can stand agog as a pod of humpback whales surges out of the water in unison, gobbling fish.

More than any other species, brown bears, as Alaska’s coastal grizzlies are known, and humpback whales are the objects of the state’s ecotourism industry. They share three attributes that make them so. Both congregate in feeding groups at well-known locations, near the towns that have the airports and the cruise ship docks. Both are most active in the summer months, the height of the tourist season. And both are among the most charismatic species on the planet.

No one knows how many people ogle bears in Alaska each year or how many book whale-watching excursions. The lack of data is attributable to the paucity of regulations governing eco-tourism. No specific license is required for either endeavor. If you want to start a whale-watching business in Alaska, all you need is a boat, a business license and a Coast Guard permit to carry people. Ditto for bear viewing, unless you fly your customers in on floatplanes.

It’s clear, though, that the numbers are rising, fast. Fish Creek, with its road access, is the busiest bear-viewing area in the state. Other areas, such as Pack Creek, which is operated by the Forest Service on Admiralty Island, and Brooks Camp, in Katmai National Park, are accessible only by boat or plane yet still attract several thousand people a year. All are places where brown bears congregate each summer to feed on salmon. But they are far from the only ones. If you’re willing to pay anywhere from $1,000 to $3,000 (and many are), an outfitter will take you to one of several other well-known feeding areas where there are no rangers and no cedar boardwalks.

Nor does anyone know how many commercial whale-watching businesses operate in the state. Each of the primary whale-watching centers—Juneau, Sitka, Petersburg and Glacier Bay National Park—supports at least a half-dozen large operations with boats that can carry twenty to sixty people at a time. There are many smaller outfits using smaller boats.

All this wildlife viewing is the subject of growing ambivalence among the state’s environmental community. It’s quite obviously more benign to shoot a brown bear with a Nikon than with a Winchester. And if you’re fortunate enough to see these animals, chances are you’ll be more inclined to want them—and their habitat—protected. But as the crowds grow, the question arises: How much attention can the bears and whales take? The short answer is, no one knows.

The science is reassuring, at least on the face of it. More brown bears live in Alaska than in the rest of the continent combined. Best guesses put the state’s population at 35,000 to 45,000 animals, and the numbers seem relatively constant. Humpbacks, a federal endangered species, are in the midst of a remarkable comeback. A hundred years ago, there were believed to be 15,000 or so in the North Pacific. In 1966, when commercial whaling was banned, about a thousand remained. Today the North Pacific population has rebounded to about 6,000. Those animals return from Hawaiian breeding grounds to the same waters every summer, feeding in small groups comprised of the same animals year after year. Because of this behavioral trait, the bulk of the whale watching affects a small portion of the larger population. Virtually every humpback spotted by tourists in Alaska is one of four hundred or so animals whose feeding areas happen to be accessible to humans.

Things become much trickier if you try to gauge the impact on the individual animals that are the subject of all the hullabaloo. A review of the data suggests two conclusions about brown bears: Unsurprisingly, the presence of thousands of tourists hanging over cedar railings with cameras and binoculars has an impact. But there has been no discernible effect on mortality or birth rates, at least not yet.

Tom Smith, a scientist with the U.S. Geological Survey who has studied brown bears for the past ten years, points out that bears—especially the females and the young ones—have more important things to worry about than ecotourists. Two out of three newborn brown bear cubs don’t survive their first year. A good number of those dead cubs—no one knows how many—are victims of bear-on-bear predation, mainly mature males looking for easy pickings. “In the world of bears,” Smith says, “the worst enemy a bear has is another bear. So at these feeding areas, the bears don’t care about people. That’s my impression.” (He’s quick to add, though, that the dynamic is different in areas where hunting is allowed. “In those settings, large males basically do not come around. I would guess that these animals have learned that the only way to get to be a large, dominant male is to have a zero tolerance of people. And so when they see people, they turn and run. Bears are intelligent.”)

Two statutes dating from the 1970s afford the humpbacks more protection than the brown bears. Under the Endangered Species Act and the Marine Mammal Protection Act, the taking of a humpback is a federal offense. Taking, in this context, is described as harassing or disturbing an animal, which, in turn, is construed as any action that changes the animal’s behavior.

That’s broad language—too broad, it turns out, to have much practical value. Whale watching in the early 1990s was often a free-for-all, with boats racing to get to the whales and then vying for the closest positions. In 1996, the National Marine Fisheries Service implemented voluntary guidelines calling for vessels to maintain at least a 100-yard distance from all marine mammals. That didn’t work. So last July, the agency gave the guidelines teeth, making the 100-yard buffer mandatory for humpbacks. That seems to have worked, at least through the latter half of last season, according to Kaja Brix, the NMFS biologist who crafted the regulation.

But regulations can do only so much. Like all wildlife, whales are unpredictable. What’s an operator to do if a humpback just happens to surface within the 100-yard limit? What if the courses of whale and boat coincide at one tragic point in time and space? In July a humpback was found floating, dead and bloated, near Glacier Bay. Investigators determined it had been hit by a large ship, with such force that the whale’s head was nearly torn from its body. Federal officials say the culprit must have been one of the many cruise ships that frequent the bay in the summer. Those officials hint that they know which ship hit the whale, but they haven’t said, at least not publicly. They’ve taken no action. The whale was a pregnant female.

In calling for more oversight of wildlife viewing—and more study of its effects—environmentalists point to anecdotes of abuse. John Schoen, senior scientist with the National Audubon Society in Alaska, has seen chaotic photos taken recently along a popular fishing and bear-viewing stream in Alaska that he declines to name. Some of the photos, he says, show people in canoes whacking bears with paddles, trying to keep them away. He’s heard stories of unscrupulous outfitters who throw food to bears to draw them in, of ecotourists who want to get so close to the bears they can touch them. “I’m a proponent of viewing,” Schoen says, “but we’re putting our heads in the sand if we think we can just take a hands-off approach. How many other examples do we have out there of people loving something to death?”

Overall, incidents of wanton abuse seem the exception rather than the rule. The half-dozen or so developed bear-viewing areas in Alaska are by most accounts well run by federal and state agencies, and most guides and outfitters are conscientious. With populations stable, the concern is focused more on the future than the present, more on what isn’t known than what is. Brix is a thoughtful enough scientist to realize she doesn’t have all the answers, nor does anyone else. “It’s very difficult to gauge whether whale watching has any population-level effect,” she says. “Determining that would require a long study of a specific population—many decades, really. Humpbacks live a long time. From a conservation standpoint, the worry is that we might not have that much time to wait.”

Barrie Gilbert has a theory. Theory is really too strong a word; it’s more of a hypothesis, or a simple observation—one that some might dismiss as wacky if not for the fact that Gilbert is among the most respected bear biologists in the world. He’s an academician, a professor emeritus at Utah State University, but he’s no ivory tower recluse. In 1977, a Yellowstone grizzly ripped much of his face off in what Gilbert characterizes as a defensive attack: he surprised the bear when he walked over a hill. Surgeons sewed his nose back on and grafted skin from his shoulder to his face. Gilbert lost an eye, but not his fascination with bears. He’s traveled the world observing bears interacting with each other and with people.

A few years ago, Gilbert was at a lake near Brooks Camp, one of the busiest bear-viewing areas in Alaska. In shallow waters several hundred feet offshore, a female brown bear waded by, looking for spawned-out salmon. Her two cubs paralleled her course on the beach, coming within just a few feet of where Gilbert stood. (They came close enough, in fact, to eat part of Gilbert’s hat, which he had set down nearby.) Conventional wisdom holds that standing near cubs when a mother grizzly is around is about as wise as bedding down on a railroad track. And yet the sow seemed unfazed; Gilbert’s instincts told him he was safe. A year or so later, he watched a female at Brooks Camp leave two cubs on a grassy patch next to a busy trail that leads to a bear-viewing platform. Then she went off to fish. While studying bears at popular viewing areas on the British Columbia coast last summer, he thought of this as he watched females take their cubs very close to viewing areas and then go fishing.

Gilbert thinks the bears may have learned to regard tourists as unwitting babysitters. “Generally speaking, the large male bears are shy of people,” he says. “I think the females may be using the people as shelter for their cubs from the males.” The kids are safe, the bears’ logic would go, so I guess I’m free to go gobble up some salmon. If this is what’s really going on, the overall effect on bear populations may well be positive. Or maybe not—who knows?

Consider the conundrums facing the wildlife biologist who tangles with such questions. Why are male bears present at one viewing area but not another? How do females react to these patterns? Does the din of a ship’s motors confuse whales? If so, to what effect? These questions are dauntingly complex.

People alter the action of bears, just as surely as they alter the behavior of marine mammals, federal statutes notwithstanding. When dealing with human intrusion, it’s nearly impossible to say with certainty whether the ultimate consequence will be beneficial to animals, disastrous or something in between. That’s true even when the intrusion involves the seemingly harmless act of just watching.