YELLOWSTONE - Hushed tones of nervous chatter percolate among the crowd of onlookers as they watch a large black wolf feed on an elk carcass. The wolf is the Druid Peak Pack's alpha male, Wolf No. 480. It's mate, a gray alpha female called Wolf No. 569, sits idly nearby on the snow-covered ground. The alpha male's brother, a big black wolf named No. 302, is perched on a small hilltop next to them keeping a watchful eye on a group of female wolves in the river bottom below.

It's a cold, gray January morning, the day before the 13th anniversary of the reintroduction of the wolf to Yellowstone National Park, the year the animals are to be removed from the protections of the Endangered Species Act. About a dozen cars line the turnout alongside the road that winds through the Lamar Valley at the north end of the park. Peering through binoculars, spotting scopes or gigantic camera lenses, wolf watchers gather every day somewhere alongside this road, even in the freezing cold of winter. On this particular morning, they stand only a few hundred yards from the spot where in 1926 park rangers trapped and killed the last known wolves of Yellowstone.

"There he is," a wolf watcher says, and all lenses swing to the right and all talking stops. A tense silence hangs in the air as a light gray shape appears on a distant snow-covered riverbank.

Conflict and turmoil, a day in the life of a pack of wild wolves, is about to unfold before the enraptured wolf watchers. All eyes are on the lone gray wolf that's slowly making its way through the snow and sagebrush toward the Druid Peak Pack.

The uncollared gray wolf that is cautiously approaching is one of two newcomers that have moved into the pack's territory this winter. The two wolves have been following the Druid Peak Pack for months in an attempt to join it or to steal some female mates from it to start their own pack.

It's a dangerous business being a lone wolf. Getting too close to the pack could mean death or serious injury, so the young wolf stops. It hunkers down in the snow and watches the pack from a short distance away, waiting for a chance, an acceptance, that may never come.

To the hard-core wolf watchers of Yellowstone, each wolf has a story. Each pack has its own societal dynamics and rivalries. Wolves leave packs to try and establish their own or to join a different pack. Battles for territory ensue. Wolves mate, raise their young, team up on kills and kill each other.

For some people, wolf watching at Yellowstone is an addiction. It's like getting hooked on a dramatic television show when every episode ends with a cliffhanger and you absolutely have to tune in to the next one to see what happens.

WOLF GROUPIES

When wolves were first released in Yellowstone, wildlife officials believed the animals would be secretive and rarely spotted by park visitors. But it's turned out that the wolves are often out in the open and don't mind being watched as long as people keep their distance.

"That kind of caught us all by surprise," says Rick McIntyre, author and Park Service wolf team member. McIntyre spends nearly every day watching wolves, tracking signals from their radio collars and recording their activities. He also acts as a public relations officer of sorts, answering questions, filling in observers on the latest drama among the packs and making sure people keep a safe distance.

In other places that have wolves, you're lucky to get a good look at them a few days a year. But in Yellowstone, you could see some on any given day. Wolves are the most sought after animals for wildlife watchers who visit Yellowstone, according to park surveys.

The wolves' unexpected visibility is a boon to scientists and a delight to the subculture of wolf-obsessed watchers that has metabolized in recent years. Some of the self-described "wolf groupies" come to the park once every few months, while others don't miss a single day of the action.

Laurie Lyman has been coming to the park every day over the past two years to watch wolves.

"You never know what they're going to do every day. It's a story that keeps unfolding," she says.

Lyman got her first taste of wolf watching 10 years ago on a trip to Yellowstone. At the time, she and her husband, Dan Lyman, were living in San Diego. They revisited the park again and again to watch wolves. Then in 2006 they packed up and moved to Montana so they could watch the animals full time.

Lyman is one of many observers who are fascinated by the complexity of the relationships between the animals. The social structures of the packs and the wolves' Machiavellian maneuvering for status keep the wolf watchers coming back to see how each Shakespearean drama will play out.

"I think if people came out and saw the wolves for themselves they would have a better appreciation for them as a society of animals," Lyman says.

Wolves remain a divisive political issue. More than 1,500 of them roam Idaho, Montana and Wyoming with about 100 to 150 established in Yellowstone National Park. The U.S. Fish and Wildlife Service, which manages wolves outside the park, is handing over management of its wolves to the states this year, but lawsuits and political wrangling over hunting and other issues seem never ending.

There is rarely a middle ground when it comes to wolves. People either love them or hate them. Lyman, of course, loves them but she's pragmatic about how many there should be.

"There are fanatics on one hand who want to keep them all - that's unrealistic. Then you have the fanatics on the other hand who want to kill them all. There has to be a balance."

A LIVING LABORATORY

Political controversy aside, the chance to study a wild wolf pack every day in such detail had never been available to modern scientists before the restoration of Yellowstone's wolves.

As the Druid Peak Pack alpha pair stands up, McIntyre is watching. He speaks into his tape recorder: "Five-sixty-nine is up and moving. Four-eighty just did a raised leg urination."

Many of Yellowstone's wolves are watched so closely they are, essentially, under a microscope. Practically every move they make is watched and documented.

Collared wolves are numbered and tracked by radio signal. Scientists examine the bone marrow of each elk the wolves kill - about three per week - to determine the fitness of the animal. Predator-prey relationships and pack dynamics are studied in great depth. Even the wolves' scat is picked up in the field and analyzed.

To understand how important the Yellowstone Wolf Project is to science, McIntyre says, imagine if a historian were able to go back in time to be with Abraham Lincoln every day in the White House during his presidency. Bringing back the wolf to Yellowstone has given biologists that kind of detailed access, something they never dreamed they would have.

TODAY'S CLIFFHANGER

The alpha male's older brother, Wolf No. 302, is one of the oldest wolves in the park at 7 1/2 years. Few wild wolves have been studied so closely for so long. The black wolf is a favorite of the wolf watching crowd. Because of his enthusiasm for female companionship, he's usually right at the center of drama in the Druid Peak Pack.

A few years ago No. 302 and his brother left the Leopold Pack and, after a year and a half of persistence, they were allowed into the Druid Peak Pack. Soon No. 302 became the alpha male but quickly lost his status to his younger brother, No. 480.

"When his younger brother challenged him [for alpha status] he just let him have it. We kind of joke around that 302 is more interested in the romantic realm than the political realm," McIntyre says.

"He likes the ladies, you know," Lyman says.

No. 302 is a strong, big male and the sole reason the young gray newcomer that's been hanging around hasn't been able to join the pack. The other wolves have accepted the new wolf, but not No. 302 who attacked him earlier this winter and nearly killed him. Six young female wolves of the Druid Peak Pack are about to enter the mating season and No. 302 is acting like he wants them all to himself.

Each day, the wolf watchers have been witnessing the saga unfold, wondering if this will be the day something final is decided. Will the new wolf be accepted into the pack? Will he give up and leave? Will he be killed by No. 302?

It's like watching The Sopranos.

At about 10 a.m., the action starts.

Suddenly.

Wolf No. 302 jumps to his feet and starts trotting across the snow. He's had enough of that lone gray wolf watching his females. The lone wolf is looking the other way and doesn't see the giant black wolf charging straight at him, picking up speed.

Cameras start clicking like crazy and the wolf watchers brace for the clash of predators that's about to erupt on the snowy stage before them, a clash that will most likely result in the death of the younger wolf. But just in time the young wolf turns his head to see No. 302 bearing down on him, bounding across the snow. The young wolf leaps to his feet and takes off running. No. 302 halts his pursuit, satisfied that he's run off the intruder.

For the moment.

Only a few minutes later, after the coast is clear, the young wolf reappears.

"He's very persistent," Lyman says, peering through binoculars. "They all like him except 302. He runs just far enough away to satisfy 302, then he comes back."

That kind of drama is what keeps the wolf watchers coming back again and again.

"We don't know how his story is going to end," McIntyre says of the young wolf. "Every day we come out thinking this could be the day something big happens."