grizzlies, yellowstone, documentary
Credit: Adam Jones / Getty Images

On a snow slope on the side of Terrace Mountain, Dunning spots several muddy sets of tracks. We pick our way through the flooded area, cursing and sinking in the muck to our knees. Soaked and muddy, we posthole up a snowfield and drop our packs in a copse of aspens on a hilltop. A flock of sandhill cranes flies from the sage and beats away, trumpeting. Shier is the first to spot Quad Mom and her two cubs, 300 yards off, three brown dots ambling along a line of snow. Shier says she had emerged from her den a few months earlier with three cubs, meaning one likely died over the winter. He thinks the other cub may have been killed by a rival male hoping to mate with its mother. We watch through the binoculars as she trots ahead of them, turning to wait as they race to catch up. She continues on with them and vanishes over a rise, swallowed up by a contour in the landscape, as if she knew we were watching her. Filming from here would be pointless, Shier says, and we could never keep up with the grizzlies over such varied terrain. "We're just going to have to work the hell out of the roads," Shier says to Dunning.

Paved, two-lane roads loop through some of the prime habitat of Yellowstone's wildlife. This affords a filmmaker like Shier an extraordinary advantage: the ability to cruise the park's roads, looking for an animal and the best vantage point from which to film it. With Dunning in a second vehicle, they can triangulate their search via cell phone, working the long switchbacks above the smoking thermal terraces of Mammoth Hot Springs that lead up past Swan Lake Flat. One afternoon Dunning spots the mother and her cubs high on the flanks of Bunsen Peak, tiny dots amid a swath of deadfall lodgepole pine left by the massive fires that swept through in 1988. Dunning peers into his spotting scope and thinks they're on a kill, but from well over a mile away, not even Shier's long lens can bring them into focus. By the next morning they've vanished again. "Clearly she's a good hunter," says Shier, with a mix of admiration and frustration. "But she's so unpredictable."

The only way Shier can counter the bear's capricious nature is to be as single-minded and determined in his hunt as the grizzly is in hers. This relentlessness may be the source of Shier's success as a filmmaker, and in Yellowstone he is hardly unusual. The park has long had a magnetic pull for obsessives, and its publicly accessible wilderness has given rise to a host of cults. WolfWatchers consists of an army of volunteers who have observed the park's wolves daily since their reintroduction in 1995. One volunteer, Rick McIntyre, has logged more than 5,000 consecutive days monitoring Yellowstone's wolf packs. Geyser gazers track the force and punctuality of Old Faithful's every spurt via webcam. And then there are the bear lovers, perhaps none so committed as Shier's friend Barbara Wehr­fritz. Wehrfritz is in her early 50s, with graying hair and glasses, and has been coming to Yellowstone to photograph bears every spring and fall for 19 years. This doesn't seem strange to anyone here; part of the attraction is to be in a community of people to whom you never have to explain your obsession. We find Wehrfritz one morning at 6 am, sitting in her car on the flats with binoculars, a spotting scope, and a legal pad, making notes about the grizzly and her cubs. An unofficial and unpaid member of Shier's crew, she is an indispensable source of intel, a third set of eyes with an absolutely singular focus on bears.

Wehrfritz receives word that another grizzly is feeding along Obsidian Creek, a few miles to the south of us, and we drive down to look. That is when I encounter my first bear jam. We go around a bend and arrive at the tail end of a line of cars stretching hundreds of yards along the roadside. Shier orders me into the driver's seat, throws open the cargo doors, and assembles his camera. He works calmly and swiftly, with an efficiency born of years of practice. Then he hoists the 70-pound rig over his shoulder and starts jogging down the road alongside the cars. The desire to document apex predators may be as old as the cave paintings of Lascaux, but the volume of people seeking an intimate connection with wildlife is overwhelming the park's infrastructure. In summer, bear jams will sometimes stretch for miles, with people abandoning their cars in the roadway and sprinting to get a better view. Shier calls it a "democratized safari," and even though the huge crowds make his job more difficult, he understands that it is a public good to permit this sort of access.

By the time I can pull over and make my way to Shier, there are more than a hundred tripods splayed along the roadside, all focused on a single grizzly casually nibbling grass in a meadow. A ranger in a highway vest marches up and down the line, yelling at gawking drivers in a futile effort to keep traffic flowing. There is something of a paparazzi vibe among the crowd. Whenever the bear glances up, the roar of motorized shutters sounds like machine-gun fire. The bear shakes its hump and turns back to munching grass, utterly indifferent to the commotion.

I find Shier off to one side of the jam. His lens has by far the longest reach of any of those present, so he can afford to hang back from the crowd. Monitoring focus and exposure on his viewing screen, he has the bear filling the frame from a hundred yards away. This isn't the hunt footage he needs, but it will do for now. The shot of the grazing bear seen through Shier's viewfinder is serene and beautiful, the crowd of humans documenting its every move cropped out. Shier understands the irony that some of the most intimate filmed sequences ever achieved in Yellowstone have been shot from a crowded roadside like this one: "If you panned out on any film scene from the Serengeti, you'd see dozens of Land Cruisers tearing across the landscape. This is no different." As he sees it, in a world where we've set nature on museumlike display, it's the only way to gather the images needed to tell a story.

There is a wide catalog of tricks used in the service of storytelling in nature films, and the fact that many are shot from a peanut gallery is the least of them. The snuffles, grunts, and roars are almost always added later, built from stock recordings or created in postproduction. Use of "filler animals" is common practice: While gathering the shots necessary to form a sequence, an editor may have to use several different animals to construct the narrative. The baby elk suckling at its mother may not be the one you see devoured a moment later. The deer that startles may not be reacting to the stalking wolf pack. But Shier makes no apologies for this, contending that it would be impossible to tell a coherent story otherwise. He sees it as a vast improvement from the bad old days of wildlife documentary, when the use of captive animals and staged situations was the norm.

Ethics today are stricter, but there is still a deep vein of sensationalism in the wildlife-filming industry. Shier would never make the kind of films with "just another host out grabbing stuff." He wants to reveal the natural world as it really is, to shock the viewer into seeing the animals as if for the first time. While Shier accepts the need for the continuity and sound tricks used by all wildlife filmmakers, he is adamant that he will film only animals being animals. "We want natural behavior. If we're impacting what the animal is doing, we're not going to get what we want anyway. If we're screwing with the animal too much, I'll just walk away."