Historically, most Native Americans revered
gray wolves, trying to emulate their cunning
and hunting abilities. However, wolves
became nearly extinct in the lower 48 states
in the early part of the 20th century because
settlers believed wolves caused widespread
livestock losses. Constantly persecuted and
targeted by large scale predator eradication
programs sponsored by the federal
government, wolves have been pursued with
more passion and determination than any
other animal in U.S. history. By the time
wolves were finally protected by the
Endangered Species Act of 1973, they had
been exterminated from the lower 48 states,
except for a few hundred that inhabited
extreme northeastern Minnesota.
Second only to humans in their adaption to
climate extremes throughout the world, gray
wolves were equally at home in the deserts
of Israel, the deciduous forests of Virginia
and the frozen Arctic of Siberia. Within the
continental United States, gray wolves once
ranged from coast to coast and from Canada
to Mexico.
Wolf groups, or packs, usually consist of a
set of parents (alpha pair), their offspring
and other non-breeding adults. Wolves begin
mating when they are 2 to 3 years old,
sometimes establishing lifelong mates.
Wolves usually rear their pups in dens for
the first six weeks. Dens are often used year
after year, but wolves may also dig new dens
or use some other type of shelter, such as a
cave. An average of five pups are born in
early spring and are cared for by the entire
pack. They depend on their mother’s milk
for the first month, then they are gradually
weaned and fed regurgitated meat brought
by other pack members. By 7 to 8 months of
age, when they are almost fully grown, the
pups begin traveling with the adults. Often,
after 1 or 2 years of age, a young wolf leaves
and tries to find a mate and form its own
pack. Lone dispersing wolves have traveled
as far as 500 miles in search of a new home.
Wolf packs usually live within a specific
territory. Territories range in size from 50
square miles to more than 1,000 square miles
depending on how much prey is available and
seasonal prey movements. Packs use a
traditional area and defend it from strange
wolves. Their ability to travel over large areas
to seek out vulnerable prey makes wolves
good hunters.Wolves may travel as far as 30
miles in a day. Although they usually trot
along at 5 m.p.h., wolves can attain speeds as
high as 45 m.p.h for short distances.
Indirectly, wolves support a wide variety of
other animals. Ravens, foxes, wolverines,
vultures and even bears feed on the remains of
animals killed by wolves. In some areas, bald
eagles routinely feed on the carcasses of
animals killed by wolves during the winter.
Antelope are swift, elk are alert, and mountain
goats can climb steep cliffs because of the long
termevolutionary effect of wolf predation.
Wolves also help regulate the balance between
these ungulates (hoofed animals) and their
food supply, making room for smaller plant-eaters
such as beaver and small rodents.
Wolves are noted for their distinctive howl,
which they use as a form of communication.
Biologists do not know all of the reasons why
wolves howl, but they may do so before and
after a hunt, to sound an alarm and to locate
other members of the pack when separated.
Wolves howl more frequently in the evening
and early morning, especially during winter-breeding
and pup rearing. Howling is also
one way that packs warn other wolves to
stay out their territory.
Early settlers moving westward severely
depleted most populations of bison, deer, elk
and moose—animals that were important
prey for wolves. With little alternative,
wolves turned to sheep and cattle that had
replaced their natural prey. To protect
livestock, ranchers and government agencies
Gray wolf
Canis lupus
U.S. Fish & Wildlife Service
Western settlers believed that the gray
wolf caused widespread livestock losses,
leading to the wolf ’s near extinction in
the lower 48 states in the early part of the
20th century. Under large scale predator
control programs, wolves were hunted
and killed with more passion and zeal
than any other animal in U.S. history.
began a campaign to eliminate wolves.
Bounty programs initiated in the 19th
century continued as late as 1965, offering
$20 to $50 per wolf. Wolves were trapped,
shot from planes and snowmobiles, dug from
their dens, and hunted with dogs. Animal
carcasses salted with strychnine were left
out for wolves to eat. Unfortunately this
practice also indiscriminately killed eagles,
ravens, foxes, bears and other animals which
fed on the poisoned carrion.
Today about 2,200 wolves live in the wild in
Minnesota, fewer than twenty on Lake
Superior’s Isle Royale, about120 in Michigan’s
Upper Peninsula, 120 inWisconsin, and about
240 in the northern Rocky Mountains of
Montana, Idaho andWyoming.Wolves
currently are being reintroduced to Arizona
and New Mexico. An occasional wolf is seen in
Washington State, North Dakota or South
Dakota. Populations fluctuate with food
availability and strife within packs, and,
primarily, due to killing by people.
Gray wolves are listed under the
Endangered Species Act as threatened
species in Minnesota and as endangered
species elsewhere in the lower 48 states.
Endangered means a species is considered
in danger of extinction throughout all or a
significant portion of its range, and
threatened means a species may become
endangered. In Alaska, wolf populations
number 5,900 to 7,200 and are not
considered endangered or threatened.
Wolf recovery under the Endangered
Species Act has been so successful that in
June 1998 the U.S. Fish and Wildlife Service
announced that it would review the species’
status and consider delisting or reclassifying
specific wolf populations where appropriate.
The wolf ’s comeback has been attributed to
a combination of scientific research,
conservation and management programs,
and education efforts that helped to increase
public understanding of wolves.
Successful reintroduction and management
programs have greatly accelerated wolf
recovery in the Rocky Mountains. Gray
wolves have greatly expanded their numbers
thanks to science-based wolf and wolf
habitat management; restoration of wolf
prey species such as deer, elk and moose;
and habitat and legal protection.
In Minnesota, where the largest wolf
population in the lower 48 states resides, a
state program provides compensation for
livestock confirmed to be killed by wolves,
and a federal program provides for trapping
of individual wolves guilty of depredation. In
other areas a private compensation program
run by an organization that supports wolf
restoration, the Defenders of Wildlife, pays
for livestock killed by wolves.
Wolf recovery and management are very
polarized, controversial, and emotional issues
often stemming from people’s attitudes, fears
and misunderstandings more than wolves
themselves. Attitudes are often based on
inaccurate information, making wolf
management perhaps more difficult than
any other wildlife management program.
For example, some people continue to carry
the unfounded fear that wolves attack people
or threaten outdoor activities. In fact, wolves
generally avoid humans. While wolves
certainly have the ability to kill people, there
has never been a verified report of a healthy
wild wolf deliberately attacking or seriously
injuring a human in North America. Wolves
can be very tolerant of human activity if they
are not deliberately persecuted so there is
rarely a reason to restrict human activity,
including logging and mining, simply
because wolves live in the area.
For the past twenty years, Yellowstone
National Park has been at the center of
debates over the wolf. By about 1930, wolves
had been deliberately extirpated from the
western United States, including Yellowstone.
After years of comprehensive study and
planning, the U.S. Fish andWildlife Service
reintroduced gray wolves into Yellowstone
and U.S. Forest Service lands in central
Idaho. In 1995 and 1996, 31 wolves from
Canada were temporarily held in pens before
being released in Yellowstone National Park.
At the same time 35 wolves were released on
remote Forest Service lands in Idaho. All of
the reintroduced wolves were fitted with
radio collars and monitored by biologists
from the Fish andWildlife Service and other
cooperating agencies. The reintroduction has
been very successful and by December 1997
about 80 wolves lived in each area.
The Yellowstone and Idaho wolves are
designated as non-essential, experimental
under the Endangered Species Act. This
designation allows federal, state and tribal
agencies and private citizens more flexibility
in managing these populations. Wolves that
prey on livestock will be removed and, if
necessary, destroyed. Ranchers may kill
wolves they catch in the act of preying on
their livestock on private lands. They may be
issued a permit to do the same on public
lands after certain conditions are met. The
experimental program has worked so well in
the northwestern United States that a
similar effort is being used to restore
Mexican wolves to their historic range in the
southwestern United States.
Mexican gray wolves are the southernmost
occurring, rarest and most genetically
distinct type of gray wolf in North America.
They once lived in the mountainous regions
of the Southwest from central Mexico
throughout portions of southern Arizona,
New Mexico and Texas. Mexican wolves, or
lobos as they were called by the Spanish-speaking
people, were extirpated by
aggressive predator control programs.
Until recently Mexican wolves only existed
in captivity. In March 1998, the U.S. Fish and
Wildlife Service released three Mexican wolf
packs into the Apache National Forest in
eastern Arizona. These wolves are the first
to exist in the wild in the United States since
1970, when the last Mexican wolf was killed.
Reintroductions will continue for 3 to 5 years
with the goal of establishing 100 wolves in
eastern Arizona and western New Mexico.
Like the Yellowstone and Idaho wolves, the
reintroduced Mexican wolf population has
been designated a non-essential,
experimental population, providing for
greater management flexibility to address
the concerns of local residents.
Wolf recovery efforts represent an
opportunity to redress past mistakes and
enhance our understanding not only of
wolves themselves, but also the complex
interactions among species in their natural
environments.
U.S. Fish & Wildlife Service
http://www.fws.gov
July 1998
After years of comprehensive study and
planning, an effort is now underway to
reintroduce gray wolves from Canada into
Yellowstone National Park and central
Idaho as part of recovery actions for the
animal. The U.S. Fish and Wildlife Service
is considering delisting or reclassifying
populations of wolves that have been
sufficiently recovered.
