Central Idaho’s Frank Church – River of No Return Wilderness is the largest contiguous wilderness area in the lower 48 States. Endless rugged mountains, wild rivers, forests and deep canyons define this land — home to numerous species of wildlife, including wolves, who have just returned after 50 years of near absence. A young couple, Isaac and Bjornen Babcock, chose this wilderness for their year-long honeymoon. But what begins as a romantic adventure becomes something much greater for the couple — and a tale of hope and celebration for every life trying to make it in the unforgiving heart of the wilderness. Buy the Blu-Ray or DVD. This film premiered April 18, 2012. (Video limited to U.S. & Territories.)

Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Canus
Species: Lupus

Size and Weight: Gray wolves are the largest canids: on average, adults have a nose-to-tail length between 4.5 and 6ft (1.4 to 1.8m), a height at the shoulder from 26 to 32 inches (66 to 81cm), and a weight measuring between 50 and 110lbs (22.7 to 50kg). The largest wolf on record weighed 175lbs (79.3kg). Males are larger than females, and northern wolves are generally larger than those in southern areas.

Physical Features: The animal’s scientific name is Canis lupis, meaning “dog” and “wolf” in Latin. Domestic dogs are descended from wolves, which closely resemble some domestic breeds like the German shepherd or malamute. However, gray wolves are larger than most dogs, and appear even larger in the winter because of their thick undercoat. Their coloring is usually a mix of gray and brown (though white, red, and black coloration has been observed) with lighter fur on its legs and belly. They have relatively short ears, and a long bushy tail. For pushing through snow, wolves have narrow chests, and when walking on top of snow, big paws to help distribute their weight. Long legs and dense muscles make wolves excellent runners. They can reach 38 mph (61kph) sprinting, but will more frequently run long distances at around 5 mph (8kph). Marathon chases help wolves tire their prey which, once caught, are quickly killed by wolves’ powerful jaws and teeth. Their mouths contains 42 teeth including carnassial teeth, unique to carnivores for cutting through meat and bone, and can snap closed with pressure exceeding 1,000lbs per square inch (6895kPa).

Life span: The life spans of wild wolves vary dramatically. Although the average lifespan is between 6 and 8 years, many will die sooner, and some can reach 13. Wolves in captivity can live up to 17 years.

Diet: Wolves are carnivores, and tend to prey on large ungulates: hoofed animals like elk, deer, and boar. When livestock is readily available to them, wolves have been known to prey on animals like sheep and cows. When ideal prey is unavailable, wolves will eat smaller mammals, reptiles, insects, and fruits and berries. Since wolves may have to wait for days between big kills, they eat a lot when they can. They can consume as much as 22lbs (10kg) in one sitting.

Geography: Gray wolves and their relatives, red foxes, have the largest natural range of any land-based mammal besides humans and possibly some rodents. Even with their habitat and population severely constricted by human activity, various subspecies of gray wolves can be found in North America, Europe, and Asia, and as far north as the Canadian Arctic and as far south as India.

Habitat: As their range indicates, gray wolves are able to live in many biomes, from Arctic tundra to dense forests, to mountains, to dry shrublands.

Breeding and Social Structure: Wolves live in tight social units known as packs. The basic unit of a pack is a monogamous breeding pair. Beyond the founding male and female, wolf packs include their most recent litter, their offspring from previous years, and occasionally unrelated wolves. The average size is about 6, but packs exceeding 30 members have been observed. The breeding pair was once referred to as the alpha male and female, but some researchers believe that wolf hierarchy is not as rigid as those terms imply. In rare circumstances, if a pack faces a high mortality rate, or if there is an abundance of prey, other wolves in the pack may breed. Wolves mate once a year, generally in early spring. Pregnant females have a gestation period of about 63 days, and produce litters of about 4-7 pups. Pups are born unable to see or hear, and remain inside the den for about 4 weeks after they’re born. After about 10 weeks pups are weaned and become part of the pack. After a year or two a pup, now a young wolf, may leave in search of its own territory, or it may stay with the pack.

Wolves communicate in several ways, often to reinforce the breeding pair’s dominance and the rest of the pack’s submissive roles. Body language, such as eye contact, facial expressions, posture, and tail positions, can have specific meanings. Wolves also use sounds—whimpers, whines, barks, and howls—and scent marking to communicate with pack mates and strange wolves in their territory. Strengthening the hierarchical relationship in a pack may lead to physical conflict, but wolves try to avoid injuring members of their pack. Companionable behavior is much more common: wolves have been observed bringing food to incapacitated pack mates, and relating to dead pack mates in a way that suggests mourning.

Depending on prey density and other conditions, a pack’s territory can be small and close to other packs’ ranges, or larger and more spread out. Territories can be anywhere between 50 and 1,000 square miles (80–1,600km²).

Risks: Pup mortality rates can be as high as 60%, and starvation is one of the main causes of natural death. Territory fights with other wolves and scuffles with large prey can lead to injuries and death, and wolves are subject to diseases like Lyme disease, and those endemic to canids, like canine mange, parvovirus, and distemper. When in close proximity to wolves, humans pose a major threat to the animals. Humans have a long history of hunting and trapping wolves. These practices are still legal in some places, and still occur even in areas where wolves are protected. Ranchers may kill or poison wolves to protect their livestock. Human destruction of wolves’ preferred habitat has forced the animals to move closer to developed areas in search of food. And when roads divide the wilderness, wolf populations can become isolated, inbred, and more susceptible to disease.

Additional Facts:

• Wolves’ sense of smell is estimated to be 100 times stronger than humans. They are reportedly able to smell prey from miles away.
• DNA sequencing now shows that domestic dogs, once thought to be bred from a mix of canids, in fact descended solely from gray wolves.
• The Egyptian golden jackal, once thought to be a sub-species of the golden jackal, is actually a type of gray wolf.
• Not much is known about wolves’ ability to perceive color, but one experiment found that they can detect red and yellow more easily than blue or green. This may be related to how important blood and urine are as sources of information.
• Wolves tend to initiate play with other wolves by bowing.
• At about 5 inches long and 4 inches wide, all wolf tracks are larger than coyote tracks, but not all dog tracks. To distinguish wolf prints from dog prints, compare patterns. Unlike dogs, wolves tend to travel at a regular pace in straight lines.
• Wolves appear in Roman, Turkish, Norse, Japanese, and Native American myths and legends.

What happens to nature after a nuclear accident? And how does wildlife deal with the world it inherits after human inhabitants have fled?

In 1986 a nuclear meltdown at the infamous Chernobyl power plant in present-day Ukraine left miles of land in radioactive ruins. Residents living in areas most contaminated by the disaster were evacuated and relocated by government order, and a no-man’s land of our own making was left to its own devices. In the ensuing 25 years, forests, marshes, fields and rivers reclaimed the land, reversing the effects of hundreds of years of human development. And surprisingly, this exclusion zone, or “dead zone,” has become a kind of post-nuclear Eden, populated by beaver and bison, horses and birds, fish and falcons – and ruled by wolves.

Access to the zone is now permitted, at least on a limited basis, and scientists are monitoring the surviving wildlife in the area, trying to learn how the various species are coping with the invisible blight of radiation. As the top predators in this new wilderness, wolves best reflect the condition of the entire ecosystem because if the wolves are doing well, the populations of their prey must also be doing well. Accordingly, a key long-term study of the wolves has been initiated to determine their health, their range, and their numbers.

Radioactive Wolves examines the state of wildlife populations in Chernobyl’s exclusion zone, an area that, to this day, remains too radioactive for human habitation.

Radioactive Wolves premiered Wednesday, October 19 at 8/7 c.

NATURE’s two-part special Dogs That Changed the World tells the epic story of the wolf’s evolution, how “man’s best friend” changed human society and how we in turn have radically transformed dogs.

From the tiniest Chihuahua to the powerful and massive English Mastiff, modern domesticated dogs come in a bewildering array of shapes and sizes, with an equally diverse range of temperaments and behaviors. And yet, according to genetics, all dogs evolved from the savage and wild wolf — in a transformation that occurred just 15,000 years ago.

In Part One, “The Rise of the Dog,” you’ll learn about how the domestication of dogs might have taken place, including the theory of biologist Raymond Coppinger that it was the animals themselves — and human trash — that inspired the transformation. The genetic analysis of Peter Savolainen of the Royal Institute of Technology in Sweden has placed the origins of domesticated dogs — and those of the first dog — in East Asia. You’ll also discover 14 dog breeds that controversial genetic studies show are the most ancient — and the best living representatives of the ancestors to all living dogs.

Preview Part Two: Dogs by Design

Over 400 breeds of dog are recognized around the world, each unique for its personality, habits, and form. Most of these breeds exploded onto the scene over the past 150 years, spurred by the Victorian-era passion for the “dog fancy” — the selective breeding of dogs to enhance particular characteristics. By tinkering with its genetics, humans made the dog the most varied animal species on the planet — and also created a host of hereditary health problems.

Despite the plethora of new shapes and sizes, dogs have retained the instincts bred into their ancestors by thousands of years of work: the urge to herd or hunt, to dig and to guard. In Part Two, “Dogs by Design,” you’ll discover how these hard-wired behaviors help different types of dogs, from hounds to herders, excel at different tasks (and why it can sometimes be so difficult to train them to do otherwise). You’ll also learn how dogs’ finely tuned senses are serving humans and saving lives. Buy the DVD. This film premiered April 2007.

The epic history of the Druids, one of more than a dozen packs now occupying the 2.2 million acres of Yellowstone, is documented in NATURE’s In the Valley of the Wolves, was produced and shot in High Definition by Emmy-award winning filmmaker Bob Landis.

On the Web site for In the Valley of the Wolves, you’ll learn how the successful reintroduction of Yellowstone’s apex predator has changed the entire ecosystem of the park, and about the threats that these majestic animals continue to face on their road to recovery.

Watch an online-exclusive video. In this video, Emmy Award-winning wildlife cinematographer Bob Landis discusses the making of the film, including the ideal circumstances for filming a predation scene; the importance of spending a vast amount of time in the field; the uniqueness of Yellowstone’s Druid wolf pack, and more.

To order a copy of In the Valley of the Wolves, visit the NATURE Shop.

Online content for In the Valley of the Wolves was originally posted November 2007.

A grizzly in his prime is the undisputed master, able to take down prey as easily as he is able to dominate the fresh kills of other predators. The wolves of Yellowstone must use their numbers to their advantage, organizing to take down their prey and defend the spoils of their hunts from the bears. Together, a strong pack of wolves can challenge a solitary grizzly, and defeat it. As these two fierce competitors test their strategies for survival against each other, an entire food chain of scavengers survive in their wake. Crafty coyotes and cunning crows take advantage of the predators’ feuds to make the most of any felled feast.

It’s a test of skills and wills in the often harsh environment of Yellowstone as two of the continent’s greatest hunters take each other’s measure. Now, join NATURE and discover who will triumph in Clash: Encounters of Bears and Wolves.

Gyrfalcons are the world’s largest and most powerful falcons.  Yet even for them, the pressure is on.  Last summer this pair’s two chicks died of starvation.  Will the conditions be right this summer?  Will their best efforts be enough to keep this year’s chicks healthy?  Filmed in HD from a ledge adjacent to the nesting site, White Falcon, White Wolf provides an intimate portrait of this magnificent species.

Meanwhile, the pack of Arctic wolves wait with great anticipation for a sign that new pups have been born to their breeding female, who has spent a great deal of time in her den. When the pups arrive, the young wolf daughter will need to grow up. For now, however, she tends to let her curiosity get the best of her. Musk ox, snowy owls, Arctic hares and Arctic foxes round out the cast, as they too try to make the most of the precious Arctic summer. Buy the DVD. The film premiered October 26, 2008.

Stretching across more than 2.2 million acres of Wyoming, Montana, and Idaho is one of the greatest expanses of unspoiled nature and wildlife anywhere on Earth — Yellowstone National Park. Designated America’s first national park in 1872, Yellowstone now receives almost three million visitors each year. Yet only a small fraction of those who glimpse the park’s stunning vistas, geological wonders, and animal residents do so during the winter months, a time when nature’s inhospitality is matched only by its serenity.

NATURE follows in the snowy footprints of Yellowstone’s red foxes, spies on the predatory warfare of wolves and elk, and climbs into the den of a grizzly bear that gives birth to two cubs while deep in hibernation. In addition to mesmerizing footage of landscapes and wildlife, trail alongside author and photographer Tom Murphy, who has been coming to Yellowstone for the past 26 winters, camping and photographing amid the silence and solitude of the park. And go behind the scenes with filmmaker Shane Moore to find out how he kept up with Murphy during an at times harrowing trek, reminiscent of the legendary John Colter’s first journey into the park nearly two hundred years ago. Buy the DVD. This film premiered in November 2006.

Photo © Tom Murphy

Lobo, as locals simply called him, was the legendary leader of a band of cattle-killing wolves that had been terrorizing cattle ranchers and their livestock. Known as the “King of the Currumpaw,” Lobo seemingly had a mythical ability to cheat death, eluding the traps that ranchers had set for him throughout the countryside.

It was up to Seton, a naturalist as well as a professional animal trapper, to exterminate this “super-wolf.” The ensuing battle of wits between wolf and man would spark a real-life wilderness drama, the outcome of which would leave a lasting effect on a new and growing movement in America: wilderness preservation.

NATURE investigates the sometimes exasperating efforts of people and wild animals to adapt to each other when their worlds collide in Animals Behaving Badly.

The escalating battle for space on this planet between people and wild animals has grown increasingly one-sided, as humanity asserts its domination. But a few intrepid species are successfully challenging, harassing, and even exploiting us on our own turf.

How people are dealing with these incursions — and what we can learn from them to the benefit of both wildlife and humans — is the amusing and enlightening focus of Animals Behaving Badly. The filmmakers traveled to various parts of the United States and Canada, and as far away as New Zealand and Australia, to show us examples of animals behaving “badly,” and of the varying human reactions.

To order a copy of Animals Behaving Badly, please visit the NATURE Shop.

Online content for Animals Behaving Badly was originally posted May 2003.