Here they are, from the common Eastern gray squirrel to the endangered Delmarva fox squirrel. Keeping Track of Squirrels Washington ground squirrels, an endangered species in Oregon, are common on the Boardman Conservation Area. The rest of the squirrels on this site are all tree squirrels and spend their time in trees. Federal Endangered (FE), Threatened (FT), Candidate (FC), or Species of Concern (FSC). The western gray squirrel's large size, bushy tail, and gray fur lacking any brown on the body or tail are keys to distinguishing it from other tree squirrels in Washington. This group of animals is common throughout Oregon in various locations depending on species. Ground squirrels like this one spend their time, as their name suggests, on the ground. There are several reasons why ,one reason is because of dormancy periods. This occasional small patch of brown is only visible upon close inspection and is the only part of the squirrel that may have any brown. Ladies and gentlemen, meet your Washington area squirrels! Population number. The main cause behind their decline is the introduction of grey squirrels from America. The red squirrel is officially classed as Near Threatened in England, Wales and Northern Ireland but is locally common in Scotland. Beloved red squirrels in the U.K. are in rapid decline, so I guess any effort (within reason) to save them is a good idea. If they had mated, the offspring would not live through the dormancy and starve or overheat. Why are red squirrels endangered? Squirrels may be taken for granted in big cities and suburbs, but one species was endangered until recently. Some squirrels also hibernate in burrows during the winter to keep warm. (1) Threatened species are any wildlife species native to the state of Washington that are likely to become endangered within the foreseeable future throughout a significant portion of their range within the state without cooperative management or removal of threats. Beloved red squirrels in the U.K. are in rapid decline, so I guess any effort (within reason) to save them is a good idea. The Washington Ground Squirrel (Spermophilus washingtoni) is a species of concern belonging in the species group "mammals" and found in the following area(s): ... Glenn, C. R. 2006. Red squirrels have been classified as an endangered species because their numbers have declined due to the spread of the North American grey squirrel that brings the virus parapox, which is deadly to native red squirrels, according to the Young People's Trust for the Environment