Editing Western gray squirrel (section)

==Habitat loss and competition==
In Washington State, the western gray squirrel was listed as a threatened species in 1993, and was reclassified as endangered in November 2023.<ref>{{cite web|access-date=2023-12-25|author=Li Cohen|date=2023-11-20|title=Western gray squirrels are now considered endangered in Washington state: "Seriously threatened with extinction"|url=https://www.cbsnews.com/news/western-gray-squirrels-are-now-considered-endangered-species-in-washington/|website=CBS News}}</ref> Populations of the western gray squirrel have not recovered from past reductions. They are threatened with [[habitat destruction|habitat loss]], road-kill mortality and disease. Habitat has been lost due to urbanization, catastrophic wild fires, and areas of forest degraded by fire suppression and [[overgrazing]], allowing the invasion of [[Cytisus scoparius|scotch broom]]. [[Notoedric mange]], a disease caused by mites, becomes epidemic in western gray squirrel populations and is a major source of mortality. Other species, such as eastern gray squirrels, fox squirrels, California ground squirrels and [[wild turkey]]s are expanding and competing with the western gray squirrel.<ref>{{cite web |url=https://wdfw.wa.gov/conservation/gray_squirrel/ |title=Western Gray Squirrels |author=<!--Not stated--> |date=2017-06-12 |website=WDFW Conservation |publisher=Washington Department of Fish and Wildlife |access-date=2018-09-27}}</ref>
[[File:20240123-western-gray-squirrel-bonelli.jpg|thumb|In the [[San Jose Hills]] near [[San Dimas, California|San Dimas]]]]
Listed as [[Local extinction|extirpated]] in some California areas, the western gray squirrel in southern California is generally found only in the mountains and surrounding foothill communities. Local rehabilitation experts recount that fox squirrels were released in urban regions of [[Los Angeles]] throughout the 20th century. Fox squirrels (''Sciurus niger'') were introduced to the Los Angeles area in about 1904. Civil War and Spanish–American War veterans residing at the [[Sawtelle Veterans Home]] on Sepulveda and Wilshire Boulevards brought fox squirrels as pets to this site from their homes in the areas surrounding the Mississippi Valley (possibly Tennessee). Other introductions of fox squirrels to the Los Angeles area may have taken place during more recent times, but detailed records are not available. These aggressive cousins drove the more reclusive western gray squirrels back into the mountains, where competition was not so strong. This non-native species introduction appears to be the largest threat in the southern California area.