Gray Wolf

California Trail


In the Zoo

Scientific Information

Scientific Name: Canis Lupus
Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Canis




Height: 2.5-2.8 feet 2 feet
Length: 4.5-6.0 feet 4-5 feet
Weight: 70-145 pounds 60-100 lbs
Maturity: 3 years 2 years

Lifestyle and Lifespan

Diet: Omnivorous
Activity Timeframe: Nocturnal
Interactivity: Social
Sexual Dimorphism: No
Gestation: 62-63 days
Lifespan in the Wild: 8 years
Lifespan in Captivity: 17 years

Geographic Range

North America, Europe, Asia, Middle East


Status in the Wild:
Threats: Population


There are up to 32 subspecies of gray wolf with variation in color from white through cinnamon, gray, and black. In North America, wolves are often a mix of browns, tans, and grey. Muzzle is usually lighter in color, longer, shaggier hair around the neck and shoulders form a mane. Large, rounded ears usually held erect, and long legs with large paws.

Species Specifics

Formerly the world's most widely distributed mammal. Gray wolves are the most mobile canid species.

Physical Characteristics

Their thick fur (they shed their winter coats as the weather warms) provides insulation with long guard hairs to keep moisture away from their skin. Their long legs and posture allow for flexibility in their movements; they can travel great distances with ease and can sprint relatively short distances. Their paws and claws provide traction and can spread to allow for better support in snow. Their hearing and sense of smell are very keen, allowing for an incredible awareness of their surroundings.



Adapted to forests, taiga, tundra, deserts, plains, & mountains


Packs generally have territories that range from 50-200 square miles. Densities can vary from about 1 wolf/7.5 square miles to 1/75 square miles. Packs in highly productive environments, such as Yellowstone, have territories of about 100-200 square miles, while wolves living in the Arctic and dependent on caribou may use areas of 20,000 square miles or more. They are habitat generalists, so one home range include many different types of landscapes. They can travel as much as 40 miles a day while hunting and often use semi-regular routes ('runways') through their territory. Dispersing wolves who are leaving their pack can travel as far as 600 miles.


Omnivorous, mostly large hoofed mammals such as elk, bison, deer and moose. Will also eat small mammals, birds, invertebrates, fish where available, & vegetation (mostly grass)

Ecological Web

Ecological Role: The wolf's niche is that of the northern predator upon large mammals. Besides humans and the wolf, the only other animals that regularly prey on large mammals in the Northern Hemisphere are cats (mountain lions in North American and tigers and leopards in Asia). Cats rarely reach the density and distribution that wolves can, however. Wolves are considered an apex predator. Prey: Generalists, hunting mostly large hoofed animals such as moose, elk, deer, sheep, goats, caribou, musk oxen & bison. More than 60% of their prey are young, weak, or older animals. Smaller mammals such as voles, beaver, and hares supplement their diet. Fish, birds, berries, & carrion are consumed seasonally, depending on location. They are also scavengers, and carcasses are known attractants for them. They are adapted to a feast-or-famine diet and cache food.

Activity and Behavior

Activity Pattern

Classified as arrhythmic, meaning they lack a particular time of period when they are most active; they have no normal activity pattern. Gray wolves have adopted more secretive and nocturnal activity patterns in parts of Europe were they coexist with people.


Wolves would probably not have become so widespread had they not adapted to living in packs. Their social nature and ways of communicating have allowed for a worldwide range, as well as the ability to take down larger prey. Though their role in ancient times was as a mesopredator, they have become an apex predator in ecosystems today.

Social Behavior

Most wolves live in packs with an average of 2-12 members (with an average of 6), though there can be more if prey is available (up to 36 was found in Alaska). In the summer, packs are smaller because their diets are more diverse. Winter hosts larger pack sizes due to integrating pups into the pack and the necessity to take down larger prey items. Packs contain parents, pups, offspring from other years, and other relatives. Rank positions are not permanent, and contests are most intense during the winter breeding period. Communication includes vision, sound, and smell. Usually howls are a territory call; lone wolves rarely howl.

Reproductive Behavior

The alpha pair is usually the exclusive breeding pair and often mate for life, however other pack members can also breed. Gray wolves commonly disperse over 30 miles before settling in a pack and reproducing. Packs generally produce one litter annually.


Litters range from 3-12, with an average of 4-6 pups. The size of the litter correlates to the size of the wolf population in the area, amount of prey available, and other environmental stresses. For example, when pack sizes are large, litter sizes are small, and vice versa.



Listed as Least Concern by the IUCN; CITIES Appendix I for Bhutan, India, Nepal, Pakistan populations, all others Appendix II; Endangered by Endangered Species Act (except certain populations). Population Trend: Stable


Gray wolves used to be the world's most widely distributed mammal. Today, gray wolves occupy only 2/3 of their former range worldwide. Because of widespread destruction of territory, human encroachment, and wolf-human conflicts, the populations have declined heavily in the USA, Western Europe, Mexico, northern Africa, and Southeast Asia. In the United States, they only occupy 5-8% of their former range, which spanned almost all habitat types coast to coast. By 1960, the gray wolf was almost entirely extirpated from the lower 48 states.

Current Threats


Our Role

Oakland Zoo partners with the California Wolf Center, which is leading the way to welcome wolves back to their native range in California. They do so by providing innovative solutions to wolf-livestock conflicts, and education programs that help people successfully share the land with wolves. The zoo is also partnered with Keystone Conservation, which is dedicated to conserving and protecting North America's native predator species, including wolves and bears. They work to create habitat for wildlife, increase range land biodiversity, and sustain and restore the working landscape in rural communities.

How You Can Help

As wolves return to their historic range in the United States (including California):- Advocate for lowering the risk of human/predator conflict, especially for ranchers. Examples of minimizing risk include: reducing attractants (remove diseased/dying animals and carcasses), livestock guardian dogs, fencing, fladry (a perceived visual barrier such as hanging flags from an electric fence wire), penning, increasing human presence, alarms, nonlethal ammunition, and keeping aggressive livestock breeds. - Contact representatives and government organizations to express your interest in wolf conservation and finding/maintaining habitat corridors, as well as a disapproval of the use of harsh chemicals (Ex: very potent new rat poisons) that kill wildlife.- Never feed wild animals; walk pets on leash; keep small pets inside; supervise small children outside; secure garbage, compost, & pet foods; stay informed!- Keep dogs inside unless supervised because hybridization with wolves can impact the overall population and genetics of wild wolves. This is an issue when the wolf densities are small and their habitats are fragmented.

Fascinating Facts

Wolves are generally accepted as the most likely ancestor of today's domestic dogs. In science, domestic dogs are a subspecies of wolf (Canis lupus familiaris). Recent molecular evidence suggests that dogs may even have been domesticated as much as 100,000 years ago.

Wolves have caused no human deaths in North America for over a century and the most recent recorded attacks by wild canids on humans involved rabid animals.

In the United States, 79% of sheep and 83% of cattle depredations are due to canids, with 15% and 18% of these losses (respectively) due to domestic dogs and the rest due mostly to coyotes. This means that though wolves are often blamed for livestock deaths, they are most often not the predators to blame.

All current canines originated in North America. First they crossed the Bering Strait to arrive to Asia and Europe, then reached South America when they could cross Panama.


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