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Western Gray Squirrel, EC 1572 EC 1572 • May 2005 $1.00 Western Gray Squirrel Sciurus griseus by S. Headley and S. Sells ave you ever watched a squirrel? The Western gray squirrel is listed Watching squirrels is fun. They in Oregon as a sensitive species, which H look like a circus act as they means it is declining in population. In jump from tree to tree. They run along Washington, the species is listed as tree branches, leaping from branch to threatened, which means there is concern branch—it is unbelievable that they can of possible extinction. Competition with move so fast and not fall! Sometimes you other species and loss of oak woodlands can hear them barking even when you and older trees may contribute to the cannot see them. You may fi nd chewed speciesʼ decline. nutshells and pinecones scattered beneath The Eastern gray squirrel, which was large trees. Up in the trees, you may see introduced from the eastern United States, squirrelsʼ large, leafy nests. looks a lot like our Western gray squir- The best time to watch squirrels is rel. Eastern gray squirrels compete for 1 to 2 hours after sunrise. As the day much of the same habitat and food as warms up, squirrels spend more time the Western gray squirrel and are more resting. They may sprawl on their belly aggressive. They also are fond of bird on tree limbs with their legs and tail seed and often raid feeders. They can be dangling. Or, they might sit on a limb troublesome for homeowners by getting with their tail curled over their back. into attics and digging up fl ower beds. Squirrels are fun to watch. They love to climb trees and eat at feeders. Sandra K. Headley and Sarah Sells, students in Fisheries and Wildlife, Oregon State University. Species description Animals are grouped according squirrels wake up at to similar characteristics and rela- sunrise, they fi rst tionships, and squirrels are part of groom them- a very large group, or order, called selves. They Rodentia, the gnawing mammals are most we call rodents. Within this group, active during squirrels are in the Sciuridae family, the fi rst 2 to a large subgroup that also includes 3 hours of the day. Squirrels spend a chipmunks, fl ying squirrels, and lot of time looking for, storing, and marmots. eating food. They often store their The Western gray squirrel is food to survive during seasons when the largest tree squirrel in Oregon. less food is available. Western gray squirrels look silvery About 3 hours before sunset, gray, except for their belly, which is squirrels usually go to their nests for white. White tips on gray hairs give the night. In the winter, they like to them a silvery appearance. They sleep in tree cavities, which are holes have a bushy, silvery gray tail with (often made by woodpeckers) in tree black hairs. Adults weigh between trunks. They also build nests called 18 to 33 ounces. They can be as long dreys high in trees. A drey is a fl at as 2 feet, including their tail. They nest made of large sticks on the out- have strong, curved claws and strong side and lined with soft leaves and legs for tree climbing and leaping. shredded bark. Dreys often are used Look for squirrel tracks the next for sleeping and raising young. time you are outside. Their front feet Female squirrels give birth after leave 1-inch-long round tracks with being pregnant for at least 6 weeks. four toe prints. The back feet leave A litter can range from one to fi ve 1 2 ⁄4-inch-long tracks with fi ve toe young, though two or three seem prints. When a squirrel runs or hops, common. Females give birth to one its trail has the hind prints in front of litter between February and June. the fore prints. Tracks are especially The young may be born in dreys, or fun to look for in the they may be born in tree cavity nests snow, when squirrels and moved to dreys when they are may leave trails from older. They are born with their eyes tree to tree. closed and without hair. You can Western gray look for babies outside of their nests squirrels are beginning in mid- to late spring. diurnal, which Squirrels are eaten by bobcats, means they are weasels, coyotes, hawks, owls, active in the day- snakes, and other predators. Humans time and sleep hunt squirrels, and many are hit by at night. When cars. 2 Where they live and why Western gray squirrels live in many pines. On a quiet day, you parts of California, Oregon, and may hear a nibbling noise Washington. In Oregon and Washington, coming from high in a tree. they live mainly on the west side of the If you look closely, you Cascade Mountains, but some also live might fi nd a squirrel holding on the east side. They generally do not a pine cone in his hands like live on the coast. In California, they live a corn cob and chewing on nearly everywhere except for the Central it. In the summer, squirrels Valley, the coast, and most of the deserts also eat green vegetation, of southern California. berries, and insects. Western gray squirrels are arboreal, Squirrels are like minia- which means they live in trees. They ture tree farmers. They help also spend time on the ground traveling new trees grow by storing between trees and looking for food. They nuts and seeds in the ground, Squirrels eat, sleep, and prefer wooded areas with lots of oak trees. hoping to eat them later. If raise their babies in trees. They also are found near streams and in they forget where they hid forests where there are maples, tanoak, them, the seeds can sprout madrone, Douglas-fi r, white fi r, and pines. into new trees. Squirrels also help plants They also live in urban parks and orchards by eating aphids, a type of insect that can near forested areas. attack Oregon ash trees and cause a dis- Squirrels eat a variety of foods. They ease called leaf roll. Squirrels can damage prefer fungi, acorns, and seeds from trees trees by chewing the bark when food is such as Douglas-fi r, true fi rs, spruce, and scarce. Creating habitat safety hazard. If woodpeckers make cavi- ties in these trees, squirrels can nest in Western gray squir- them after the woodpeckers leave. rels need you to If you wish, you can attract squirrels maintain and create to feeders with peanuts, walnuts, corn, habitat for them! If you sunfl ower seeds, and suet. Squirrels like have oak trees in your to eat corn. Simple feeders can be made to habitat area, thatʼs a hold an ear of corn. There are many other good start. If not, you types of squirrel feeders, which you can can plant oaks or other trees that produce buy at bird and nature stores or online at seeds or nuts, such as maple, walnut, sites such as http://www.wildwoodfarms. hazelnut, spruce, sugar pine, ponderosa com/, which has over a dozen fun and pine, and lodgepole pine. Knowing your interesting designs. Please note, however, areaʼs soil type and weather will help you that feeding squirrels can attract the non- decide which species to plant. native Eastern gray squirrel rather than You can provide shelter for Western the more shy Western gray squirrel. Too gray squirrels by leaving large trees and many squirrels in one area can drive away dead or dying trees if they do not pose a birds and other desirable wildlife. 3 Fun facts Tree squirrels donʼt hibernate. They store nuts to last through the winter. Squirrels can use their tail as a parachute and to land on if they fall out of a tree. Squirrels often bury nuts in the fall to eat during the winter. There are more than 270 species of squirrels. They live in a variety of habitats around the world. Learn more! Csuti, B.A., et al. 2001. Atlas of Oregon Squirrels look different than Wildlife: Distribution, Habitat, and chipmunks; they have no stripes Natural History. Oregon State Univer- on their faces. sity Press, Corvallis, OR. Some squirrels are arboreal (live Link, R. 1999. Landscaping for Wildlife in trees), while others are fossorial in the Pacifi c Northwest. Washington (live underground in burrows). Department of Fish and Wildlife. University of Washington Press, Seattle. Maser, Chris. 1998. Mammals of the Pacifi c Northwest: From the Coast Additional wildlife publications in to the High Cascades. Oregon State this series are available on the OSU Extension Service website at http:// University Press, Corvallis, OR. extension.oregonstate.edu (choose The Squirrel Place (http://www. “Publications”). squirrels.org). Verts, B.J. and L.N. Carraway. 1998. Land Mammals of Oregon. University of California Press, Berkeley, CA. Wildwood Farms (http://www. wildwoodfarms.com/). Youth, H. 1997. Enjoying Squirrels More (Or Less!). Bird Watcherʼs Digest. Pardson Corporation, Marietta, OH. Oregon 4-H Wildlife Stewards © 2005 Oregon State University. Track illustrations are used courtesy of Kim A. Cabrera. This publication was produced and distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Extension work is a cooperative program of Oregon State University, the U.S. Department of Agriculture, and Oregon counties. Oregon State Univer- sity Extension Service offers educational programs, activities, and materials—without discrimination based on race, color, religion, sex, sexual orientation, national origin, age, marital status, disability, or disabled veteran or Vietnam-era veteran status. Oregon State University Extension Service is an Equal Opportunity Employer.
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