Squirrels of Effie Yeaw

April 15, 2019

Written by Larry Klink

Squirrels are a common site at Effie Yeaw Nature Center. The 2 varieties most often seen are the Fox Squirrel and the California Ground Squirrel. 

The Fox Squirrel is the golden brown tree squirrel you will see foraging on the ground and in the trees.They make nests in tree cavities and sometimes, leaf nests in in the forks of trees.These squirrels eat nuts, tubers, bulbs and sometimes insects and bird eggs. Like most squirrels, they create caches of nuts to be used when food becomes scarce. They can have 2 litters in a year. The fox squirrel is not native to California. The only well documented instance of introduction says they were introduced into Los Angeles County circa 1904 . These squirrels  have spread rapidly.


 Eastern Fox Squirrel photo by Larry Klink

 Squirrel leaf nest photo by Larry Klink

The California Ground Squirrel is a mottled gray squirrel. It has a white collar around its neck and its tail is not as bushy as its tree dwelling cousins. These squirrels live in underground burrows. Interestingly, they may live in a community burrow, but each has its own entrance. They eat nuts and fruits. Female ground squirrels are promiscuous. One litter can contain babies with different fathers. Ground Squirrel's are also popular prey for rattlesnakes. They use a variety of interesting techniques to discourage the snake, including rubbing themselves with the shed skin of a snake to disguise their own scent.

 California Ground Squirrel photo by Larry Klink

The Western Gray Squirrel is another common squirrel in the area around Sacramento. It is the larger, silver-gray squirrel with white underbelly and big bushy tail. I have been told that the Western Gray Squirrel sometimes makes an appearance at Effie Yeaw but I have not seen one there. These squirrels have a strong preference for acorns and pine nuts. Though they will forage on the ground, they prefer to travel in the tree canopy. The gray squirrel image shown below was photographed on the American River Parkway near Folsom.  


 Western Gray Squirrel photo by Larry Klink

Some believe that the fox squirrel is pushing the gray squirrel out of its natural range because the fox squirrel has a more diverse diet and raises 2 litters a year.  However, gray squirrel habitat loss, drought and susceptibility to mange may also contribute to gray squirrel loss. 

Fox squirrels and gray squirrels can breed together. When they do, one of the possible outcomes is a black squirrel. I have been told that there is a black squirrel at the nature center, but I have not seen it.

As an aside, the Eastern Gray Squirrel has made its way into Sacrament County. It was introduced into the Golden Gate Park area of San Francisco and has spread from there.