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California Ground Squirrel Mammals That Are Easily Observed

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California Ground Squirrel Mammals That Are Easily Observed ne of the most recognizable and com- Ground squirrels live in large colonies in a One result of a diet of soft food handouts is Omon mammals in neighborhood parks network of burrows. There are several species that the natural wear of their teeth ceases. and yards is the squirrel. Squirrels have be- native to California. They all nest under- This can lead to improper diet and overgrown, come accustomed to people and manage quite ground and have one to three litters per year. extruding teeth that inhibit eating and ulti- well in urban areas. They are one of the few Most young are born in March and April, mately result in starvation. California Ground Squirrel mammals that are easily observed. with an average litter of seven pups that stay For the safety of humans and other animals, underground for six weeks. These prolific it is always best to refrain from feeding any The California ground squirrel is com- rodents are prey for many predators: bobcats, wildlife. mon in grasslands and makes its nest un- coyotes, hawks, owls, eagles, foxes, weasels, derground. They are active during the day and large snakes. and use cheek pouches to carry food to their Both tree and ground squirrels have a burrows. During times when food is scarce, varied diet consisting of nuts, seeds, fruit, IF THEY ARE IN OR UNDER they enter a period of inactivity and survive buds, shoots, insects, mushrooms, bird eggs, YOUR HOUSE on stored fat during summer (estivation) and and nestlings. As with other rodents, their in- Squirrels in your attic or under the house winter (hibernation). These social animals cisors grow continually to compensate for the can be real pests. Before plugging any entrance have one litter per year of about seven young. wear from tough-shelled seeds in their diet. holes make sure the squirrels are out and won’t Adults aggressively defend helpless pups from Ground squirrels should not be confused be trapped inside. Do not approach a squirrel rattlesnakes. Aryan I. Roest with tree squirrels. Although both climb trees, that is acting abnormally or looks sick! Squir- Western gray squirrel the two can be distinguished by their re- rels contract and transmit diseases that are sponses to danger: frightened ground squirrels harmful to humans, including rabies and the IN THE WILD retreat into burrows, tree squirrels climb a tree plague, although actual cases are rare. As with In California, there are over 11 species of or high structure. any wild animal that might be sick, maintain tree and ground squirrels. Tree squirrels are ex- a safe distance and notify the animal control cellent climbers. They use their characteristic center in your area. long bushy tails for balance, communication, DO NOT PICK UP LIVE OR DEAD and to keep warm as they sleep. The nest is a SQUIRRELS WITH YOUR BARE HANDS. large, hollow, ball-shaped mass of twigs and IN YOUR YARD bark, usually lined with moss, dead leaves, and Watching squirrels go about their daily grass. These nests, called dreys, are most easily activities can be a rewarding experience. Enjoy seen in deciduous trees in the fall. Tree squir- them at a distance—don’t try to make them rels occasionally nest in holes in tree trunks. “wild pets.” Some species have one litter per year, others In the fall, tree squirrels bury acorns and Edward S. Ross may have two. An average of four young, other nuts to eat later. This often results in California ground squirrel called pups, are born blind and hairless. These new trees being planted when they fail to lo- squirrels are adapted to life in the trees and cate buried nuts. Offering handouts of food may be more vulnerable on the ground. disrupts this important planting role, as well Joyce Kilmer as interfering with their natural diet. squirrel pups SHARING THE ENVIRONMENT Visitor Centers & Recreation Services TOGETHER ARDENWOOD HISTORIC FARM LIVING WITH We can share space safely with squirrels by Fremont 510-796-0199, [email protected] understanding their specific needs. To encour- Fox Squirrel age a harmonious existence we must allow BLACK DIAMOND MINES squirrels to forage for their own food. By not Antioch 925-757-2620, [email protected] The fox squirrel is a non-native tree squir- offering handouts, we maintain a safe environ- rel from the Eastern U.S. commonly seen in COYOTE HILLS REGIONAL PARK ment for squirrels and human beings. Learn- urban parks in California. It spends most of Fremont 510-795-9385, [email protected] ing to live with the wild creatures that visit Squirrels its life in the trees or near them on the ground our gardens and homes is not difficult as long CRAB COVE at CROWN BEACH foraging for nuts, mushrooms, and berries. as we understand their ways. Alameda 510-521-6887, [email protected] They live about seven years and rarely hiber- nate for more than a few weeks at a time SUNOL REGIONAL WILDERNESS during extremely cold spells. They make a nest Sunol 925-862-2601, [email protected] in a tree and usually have two litters of three or four young in spring and summer. TILDEN NATURE AREA/EEC WHAT YOU CAN DO and LITTLE FARM Bird feeders offer a source of food not Berkeley 510-525-2233, [email protected] normally in squirrels’ diets. Squirrels are very clever and persistent in their endeavors to get AQUATICS UNIT 510-690-6620, [email protected] these free meals of seed. Keep in mind that they are quick to take advantage of a readily REGIONAL PARKS BOTANIC GARDEN available food source. c/o Tilden Regional Park, Berkeley There are ways to discourage squirrels while 510-841-8732 continuing to feed and watch birds without [email protected], www.nativeplants.org losing the food to squirrels. The feeder should OUTDOOR RECREATION UNIT be far away from high structures or the squir- Distict-wide programs 510-544-2512 rels will jump to it. There are poles available [email protected] for sale that squirrels aren’t able to climb, and some bird feeders are designed to exclude squirrels. This brochure is provided as a public service of the Interpretive and Recreation Services Depart- Joe DiDonato A book that offers tips for protecting bird- fox squirrel ment of the East Bay Regional Park District. feeders is called Outwitting Squirrels by Bill Adler, Chicago Review Press, 1988. EAST BAY REGIONAL PARK DISTRICT Text by Jessica Sheppard 2950 Peralta Oaks Ct., P.O. Box 5381 Oakland, CA 94605-0381 East Bay Regional Park District 1-888-EBPARKS www.ebparks.org TDD phone 510-633-0460 t C s on CHLORIN ED E S F Po s S R um E E C E % O 0 e R 100% r P www.ebparks.org 10 12/07.
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