Crestone Eagle, March 2006:
Small Wild Neighbors (Part 2 of 3)
Part 2 of our study of small wildlife living in the Crestone
area, we will examine squirrels, chipmunks, prairie dogs,
marmots, beavers and gophers.
There are three types of squirrels, the ground squirrel, the
flying squirrel and the tree squirrel.
In North America, there are several species that are regarded
as tree squirrels. Tree squirrels are found around Crestone
and throughout most of the US, other than the treeless Great
Plains and Great Basin areas. They do not hibernate, and are
active year round. You may not see them as often in the winter,
since they stay in their nests to conserve body heat.
Colorado is home to three kinds of tree squirrels—fox
(Sciurus niger), pine (Tamiasciurus hudsonicus),
and the Abert’s squirrel (Sciurus aberti).
The red fox squirrel is more common on the eastern plains
and not seen in this area. Abert’s squirrel does live
around here, a resident of ponderosa pine forests. The smaller,
but noisier, pine squirrel, sometimes called a chickaree,
occupies high timber and is also seen around Crestone. Abert’s
and fox squirrels are about the same size (up to 20 inches
long and 2 pounds in weight), although Abert’s has longer
fur and therefore looks larger. The pine squirrel is much
smaller—up to 14 inches long and weighing only
about 9 ounces.
Every part of Colorado is home to at least one species of
ground squirrel. On the grasslands of the eastern plains are
the spotted ground squirrels (Spermophilus spilosoma).
In the foothills and on western mesas and canyons lives the
brown rock squirrel (Spermophilus variegates). The
brownish gray Wyoming ground squirrel (Spermophilus elegans)
lives in the mountains and sagebrush-covered basins. The white-tailed
pronghorn squirrel (Ammospermophilus leucurus) lives
in the hot desert shrub lands of the western valleys, while
the golden-mantled ground squirrel (Spermophilus lateralis)
lives throughout the mountains.
Squirrels use their tail for many things, with its primary
function being for balance. This enables the squirrel to maneuver
quickly without falling. It is also used as a parachute when
the squirrel does fall, plus it acts as a blanket in the winter.
Squirrels also use their tail to communicate with other squirrels.
The most common tail gesture is the flicking which means get
Most squirrels eat nuts, seeds, grain, and fruit. When natural
food is scarce, they will eat anything they can find, including
all forms of human junk foods. They also eat mushrooms, plants,
and bulbs that may be poisonous to humans. This is due in
part to their very short digestive tract, making them able
to handle these compounds.
On the ground, squirrels hop, moving twelve to twenty inches
at a time, but they sometimes can cover up to six feet in
one bound. Squirrels build nests called dreys, made of twigs
and leaves. Their area is usually one to seven acres in size.
They will find and store their food in this area and must
keep other squirrels from invading this space.
Squirrels in captivity have lived to be twenty years old,
yet most wild squirrels will die before their first birthday,
due to being run over by vehicles. If they do survive autos,
they should live five or six years.
Squirrels mate in the late winter or very early spring. Babies
are born in the spring, without fur and blind, usually with
four to a litter. They are called babies or infants while
in the nest. For the first year they’re referred to
Chipmunks are rodents that live in forests, open woodlands,
and brushy areas in North America. There are over twenty species
of the chipmunk, and Colorado is home to five species. The
most widespread is the least chipmunk (Tamias minimus),
which lives over most of the central and western parts of
the state. The Colorado chipmunk (Tamias quadrivittatus)
lives in southern Colorado and northward along the foothills
of the eastern slope. The Hopi chipmunk (Tamias rufus)
lives on the Colorado plateau. The Uinta chipmunk (Tamias
umbrinus) is a species of the central mountains. The
cliff chipmunk (Tamias dorsalis) occurs in northwestern
Colorado. They are not easy to distinguish from each other
in the field. The larger ones are up to 9 inches long and
weigh about 2 ounces.
Chipmunks are lively animals, active by day and tolerant
of people. Like squirrels, they are known to become beggars
at picnic grounds. Like all wild mammals, you should never
feed them, as they get dependent on handouts. They do bite,
and carry fleas that may carry diseases. Their native diet
is seeds, berries, flowers and insects. Chipmunks have cheek
pouches in which they carry food to store in their burrows.
Food is stored for winter, and the animals usually do not
come above ground while the snow covers the land above their
home. They sleep for several days and then awake to feed,
as their body does not store fat to sustain them like some
deep hibernators. Some chipmunks dig extensive burrows which
can be over 11 ft. long. These burrows often have more than
one entrance and have chambers in which they store their winter
food. Other chipmunks make nests in logs or in bushes.
Chipmunks resemble some species of squirrels, yet have peculiar
characteristics that help to distinguish them. As a rule,
the chipmunk is smaller in size and has prominent stripes
on the head. They weigh from 1 to 5 ounces and are about 4
to 10 inches in length. Chipmunks make a sound that resembles
those of birds. They tend to live for 2-4 years or more in
the wild. They are hunted by hawks, snakes, foxes, coyotes,
house cats and a few other animals.
Prairie dogs are found throughout most of the western United
States, including Colorado. There are not too many of these
critters here in Crestone, but according to Ron Rivele of
the DOW, they are nearby.
As members of the genus Cynomys (Greek for “mouse dog”),
all species of prairie dogs are related to ground squirrels,
chipmunks and marmots. Of the five species of prairie dogs,
three of their species call Colorado home:
Black-tailed prairie dog (C. ludovicianus), white-tailed
prairie dog (C. leucurus), and the Gunnison’s
prairie dog (C. gunnisoni).
Prairie dogs are fat robust rodents. They weigh 1 1/2 to
3 lbs. The head and body are 11 to 13 inches long, with a
tail length of 3 to 4 inches. They are yellowish in color,
with darker ears and a pale to whitish belly.
Prairie dogs have a high-pitched, bark-like call. Studies
show that prairie dogs possess the most sophisticated of all
natural animal languages. They apparently use different sounds
to identify various predators, which include hawks, owls,
eagles, ravens, coyotes, badgers and snakes. They can run
up to 35 miles per hour for short distances. Prairie dogs
only have one defense that works—raising the alarm and
Most of the prairie dogs found in Colorado hibernate during
the winter. Their burrows are called towns. They have a social
system composed of one male and several close-kin females
plus their offspring. Their lifespan is 3-5 years in the wild,
and have lived up to 8 1/2 years in captivity. Although they
are almost exclusively vegetarian, nursing females have been
observed both cannibalizing and communally nursing each other’s
pups. They acquire all of their water from the food they eat.
One thing marmots (Sciurid) are good at is sleeping,
with 80 percent of their time staying in their burrow. They
are about the size of a house cat and all of them live in
the northern hemisphere. They are the same as groundhogs,
just not called that here in Colorado (mainly know as woodchucks
in the southeast). They are a highly social species; in some
cases offspring will live several years together with their
parents and, in the case of alpine marmots, may even help
rear younger siblings. When alarmed by predators (raptors,
carnivores, and people) marmots whistle or chirp. These species
specific vocalizations are referred to as alarm calls.
Of the six species of marmots found in North America, only
yellow-bellied marmots (Marmota flaviventris) are
common in Colorado and are the best studied of all marmot
species. As high as the very top of Colorado’s 14’ers
you will find the yellow-bellied marmot. As far as yellow-bellied
marmots go, the males will disperse as yearlings and try to
find one or more females. Females breed as 2 year olds. Litter
sizes average is four pups.
Is it true that a marmot (groundhog) can predict how long
the winter season will continue, depending on if it sees its
shadow or not on February 2 of each year? Because of this
silly belief, Groundhog Day is the only US holiday directly
named after an animal!
Beavers (Castor Canadensis) are very common in Colorado
and, yes, they are in our area too. Since they live in and
around ponds and streams, we don’t see them right here
in town, but we don’t have to wander too far to see
them or the dams that they build.
Beavers are the largest of all rodents. They measure more
than three feet in length, and weigh up to 55 pounds. They
have a broad, flat tail and webbed feet. They feed on the
upper, tender branches, leaves and bark of trees, but they
do not eat the inner wood. Their den houses a nuclear family
of parents, yearlings, and four or five kits. There is a single
litter of young born each year following a four month gestation
You may not see them, but we have a lot of these critters
here in Crestone. Who else do you think is digging all those
holes outside of your house?
Gophers (Thomomys spp) are burrowing rodents that
get their name from the fur-lined external cheek pouches,
or pockets, that they use for carrying food. They are well
equipped for digging tunnels, with powerful forequarters,
large-clawed front paws and highly sensitive facial whiskers
to assist movements in the dark. An unusual adaptation is
the gopher’s lips, which can be closed behind the four
large incisor teeth to keep dirt out of its mouth when it
is using its teeth for digging.
Gophers range in length from 6 to 10 inches. They are seldom
seen, although you might get lucky and see one feeding at
the edge of an open burrow, or moving to a new area, but for
the most part they remain underground in the burrow system.
We know that they are around by the mounds and holes that
One gopher may create several mounds in a day. Here in Crestone,
mound building is most pronounced during spring or fall when
the soil is moist and easy to dig. Mounds are formed as the
gopher digs its tunnel and pushes the loose dirt to the surface.
The hole, which is off to one side of the mound, is usually
plugged. Although mole mounds are sometimes mistaken for gopher
mounds, it is easy to tell the two apart. Mole mounds appear
circular, in profile they are volcano-shaped. There are no
known moles residing here in Crestone. There is just one species
of mole in Colorado, and it is restricted to the eastern plains.
Gophers live in a burrow system that can cover an area of
200 to 2,000 square feet. The burrows are about 2 1/2 to 3
1/2 inches in diameter. Feeding burrows are usually 6 to 12
inches below ground, whereas the nest and food storage chamber
may be as deep as 6 feet. Short, sloping lateral tunnels connect
the main burrow system to the surface and are created during
construction of the main tunnel for pushing dirt to the surface.
Gophers do not hibernate and are active year-round. They
can be active at all hours of the day. Gophers usually live
alone within their burrow system, except females with young
or when they are breeding. They can live up to 3 years. Females
produce one to three litters per year, with five to six young.
Gophers are herbivorous. They feed on a wide variety of
vegetation. They use their sense of smell to locate food.
Most commonly they feed on roots and fleshy portions of plants
they encounter while digging. Sometimes they feed above ground,
venturing only a body length or so from their tunnel opening.
Burrow openings used in this manner are called “feed
holes.” They are identified by the absence of a dirt
mound and a circular band of clipped vegetation around the
hole. Gophers will also pull entire plants into their tunnel.
That does it for part 2 on small wildlife. For Part 3, which
will be covered in the next Eagle, we will take a look at
the different snakes around our area.
to the Eagle!