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Exploring the beautiful nature of California
California Nature: Chipmunks & Squirrels
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Chipmunks are small striped squirrels in the
genus Tamias. Except for one species in northeast Asia,
they are found only in North America. All chipmunks have facial
stripes. Chipmunks are diurnal mammals and hibernate in cold
weather. They have internal cheek patches for carrying food.
Unlike most ground-squirrels which store fat for energy during
dormant periods, chipmunks have large underground caches of food
the the occasional periods of waking and for use in early spring
in areas still covered by snow. Seeds and fruits constitute most
of their diet although the Least Chipmunk eats a fair amount of
insects and even lizards
Squirrels are almost everywhere in California,
from the coastal area to the inland. These incredibly agile,
cute, and wacky characters are endearing to many, with the
exception of bird lovers, since a squirrel can empty out a bird
feeder in a matter of minutes! Incredible climbers and jumpers,
Squirrels can hang from any angle it seems. The California
ground squirrel, Spermophilus beecheyi, is one of the most
troublesome pests to homeowners and gardeners. It is found in
nearly all regions of California except for the Owens Valley
southward into the desert regions.
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Merriam's Chipmunk ranges
through the foothills of central and southern
California. It particularly like chaparral areas
and scurries around on branches and logs. When
they are scampering in trees they jump from
branch to branch, using their fluffy tails for
balance. Where their range and the range of the
California chipmunk overlap, the two may
interbreed.
Evidence indicates that over part of its range
Merriam’s Chipmunk occurs in two very similar
forms that remain distinct. They can be
distinguished by skull and penis bone
characteristics, and by their appearance. The
form found in the Eagle, San Bernardino, Little
San Bernardino, San Jacinto, and Santa Rosa
mountain areas is paler in summer, with the dark
stripes on its back more reddish, than the
typical form of Merriam’s Chipmunk.
Merriam's chipmunk's calls are distinctive.
Perched on top of a stump or rock, the chipmunks
vocalize long and vigorously, and the "chip"
sound is often followed by a burst of sound
called a "terminal pulse."
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The California Chipmunk is active throughout
the year. It feeds on a variety of seeds, fruits, and flowers,
including pinyon nuts and acorns. The burrows, which have short
side branches that serve as turn-around spots or fecal pellet
depositories, are usually protected by large boulders.
The California Chipmunk often calls from bushes, but not from
trees. Its repertoire of calls includes the chip, chuck, and
chipper, and a trill. An individual may chip, usually from the
top of a boulder, for up to five minutes at a rate of 100 to 165
chips per minute, each one accompanied by a tail flip. The chip
stimulates other chipmunks to call, while the chuck, which can
also occur at a rate of 160 per minute, appears to quiet other
chipmunks. The chipper call is given as the animal runs for
cover.
The California chipmunk occurs in the San Bernardino, Eagle, San
Jacinto, and Santa Rosa Mountains. of southern California, and
in extreme south-central California near the Mexican border in
Imperial and San Diego counties. It is abundant in pinyon-juniper,
chamise-redshank and mixed chaparral, and ponderosa pine
habitats within its range.
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The Fox Squirrel, named for its striking fox-like tail, is the largest squirrel in the western hemisphere. Weighing in at about 1 kg, it is about twice the size of a gray squirrel. Fox squirrels are highly variable in color, and their coats can be anywhere from creamy tan to all black.
Fox squirrels prefer open park-like habitats with scattered mature pine trees and an open understory. In some parts of southwest Florida fox squirrels are quite abundant on golf courses that have retained patches of open pine-oak forest. Fox squirrels use tree cavities for sleeping quarters and birth dens, but they also construct large leaf nests and stick nests in some areas. They are solitary, except during the breeding season, during which time mating chases sometimes occur. Females conceive in November and 2-3 young are born in January. The young remain in the nest for about 75 days, and are weaned at 90 days.
Fox squirrels are strictly diurnal, and usually do not begin foraging until mid-morning. Long leaf pine seeds and turkey oak and live oak acorns are among their favorite foods and they also eat fungi, buds, bulbs and insects. From May to October these squirrels cut green longleaf pine cones and strip off the bracts to get at the seeds. You can tell where a fox squirrel has been feeding because of the large piles of cone pieces on the ground.
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The California Ground Squirrel
is easily identified as they forage aboveground near their
burrows. The ground squirrel’s head and body measure 9 to 11 inches and its
semi-bushy tail adds another 5 to 9 inches in length. The fur is brownish gray
dappled with buffy white along the back; the sides of the head and shoulders are
light gray to whitish. One subspecies that occupies most of northern California
has a dark, triangular-shaped patch on its back between the shoulders; this
patch is missing from other species.
Ground squirrels live in a wide variety of natural habitats but usually avoid
thick chaparral, dense woods, and wet areas. Ground
squirrels live in a burrow system where they sleep, rest, rear young, store
food, and avoid danger. The burrow openings are about 4 inches in diameter, but
can vary considerably. The burrows may be 5 to 30 feet or more in length and may
go 2 to 4 feet below the soil surface. Ground squirrels live in colonies that may include several dozen
animals in a complex of burrows. More than one squirrel may live in a burrow.
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Bats
Bears
Bison
Bobcat
Chipmunks
& Squirrels
Deer & Elk
Feral Horses
Foxes
Gophers
Gray Wolf
Jaguar
Mice & Rats
Mountain Lion
Porcupine
Rabbits
& Hares
Raccoons
River Otter
Sheep
Shrews, Moles,
& Opossum Skunks
Weasels & Minks
Wolverine and Badger |
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