Tree Squirrels

Identification | Biology | Damage ID | Management | Resources

Figure 1. Eastern gray squirrel (Sciurus carolinensis).  

Learning Objectives

  1. Demonstrate the ability to educate clients about control options.  
  2. Provide a diagram of typical sets used to capture squirrels. 
  3. Identify various risks involved with homes infested with squirrels. 

Identification 

  1. Fox squirrel (Sciurus niger
  2. Eastern gray squirrel (Sciurus carolinensis
  3. Western gray squirrel (Sciurus griseus
  4. Tassel-eared squirrel (Sciurus aberti
  5. Red squirrel (Tamiasciurus hudsonicus
  6. Douglas pine squirrel (Tamiasciurus douglasii
  7. Southern flying squirrel (Glaucomys volans
  8. Northern flying squirrel (Glaucomys sabrinus

Legal Status 

Fox and gray squirrels usually are classified as game animals. To kill tassel-eared squirrels and flying squirrels typically is not allowed. Check with local or state authorities to determine the legal status of squirrels in your area.  

Physical Description 

In this module, tree squirrels are divided into 3 groups: large tree squirrels (fox and gray squirrels), pine squirrels (red and Douglas pine squirrels), and flying squirrels. Large tree squirrels typically are orange-brown, but color varies greatly from all black to silver gray. Black bodies with white-tipped ears are common in some South Carolina coastal areas. At least 12 or 13 color varieties occur in fox squirrels. Ohio and Michigan fox squirrels are grizzled gray-brown above with an orange underside. Several color variations may occur in a single population.  

Eastern gray squirrels typically are gray, but have some variation in color. Some animals have a distinct reddish cast to their gray coat. Black individuals are common in northern parts of their range. Local populations of white gray squirrels are found in western North Carolina, upstate New York, and other localities. Though not albino, white squirrels have gray on the back of their heads, necks, or shoulders.  

Western gray squirrels are gray above with sharply distinct white under parts. They are similar in size to the eastern gray squirrel. Tassel-eared squirrels are similar in size to gray squirrels. The most common color is gray above with a broad reddish band down the back. Their most distinguishing characteristic is the 1-inch long black ear tufts.  

Two species of pine squirrels occur in North America: red squirrels and Douglas pine squirrels. Red squirrels are red-brown above with white under parts. Douglas squirrels are gray-brown above with yellowish under parts. Both species have small ear tufts and often have a black stripe separating the dark upper color from the light belly.  

Two species of flying squirrels occur in North America, and it can be difficult to distinguish them. Both may be various shades of gray or brown above and lighter below. A sharp line of demarcation separates the darker upper body from the lighter belly. The most distinctive characteristics of flying squirrels are the broad webs of skin connecting the fore and hind legs at the wrists, large black eyes, and the distinctly flattened tail.  

Large tree squirrels include fox squirrels (Figure 1) that measure 18 to 27 inches from nose to tip of tail. They weigh about 1¾ to 2¼ pounds. Eastern gray squirrels measure 16 to 20 inches. They weigh 1¼ to 1¾ pounds. Pine squirrels are considerably smaller. They are 10 to 15 inches long and weigh 1/3 to 2/3 pounds. Southern flying squirrels are 8 to 10 inches long. Northern flying squirrels average 10 to 12 inches. 

Species Ranges 

Fox squirrels occur in much of the eastern and central US and in several locations in the West, where they have been introduced (Figure 2a). Tassel-eared squirrels are restricted to Ponderosa pine forests in the Southwest, usually at altitudes above 5,000 feet. They occur in Wyoming, Colorado, New Mexico, Arizona, and Utah (Figure 2a).  

Figure 2a. Distribution of fox squirrels (dark) and tassel-eared squirrels (light). Image courtesy of PCWD. 

Figure 2b. Distribution of eastern gray squirrels (dark) and western gray squirrels (light).  
Image courtesy of PCWD. 

Eastern gray squirrels have a similar range to fox squirrels but do not occur in many western areas of the fox squirrel’s range. They have been introduced in several locations and often are found in urban areas (Figure 2b). Western gray squirrels are confined to the west coast and western Nevada (Figure 2b).  

Pine squirrels occur across northern North America, south into the Appalachians and Rockies, and on the west coast. Red squirrels often are associated with coniferous forests. Douglas squirrels are restricted to the west coast from southwestern British Columbia south through the Sierras to northern Baja California (Figure 2c).  

Figure 2c. Distribution of red squirrels (dark) and Douglas squirrels (light). Image courtesy of PCWD. 
Figure 2d. Distribution of northern flying squirrels (dark) and southern flying squirrels (light).  
Image courtesy of PCWD. 

Northern flying squirrels occur across northern North America. Their range extends south into the Appalachians and Rockies. Southern flying squirrels occur in the central and eastern US (Figure 2d). The ranges of the 2 species significantly overlap. 

Voice and Sounds 

Squirrels emit a variety of sounds including churrs, barks, and squeals. Churrs express anger, barks act as warnings, and squeals occur when a squirrel is terrorized or in pain.  

Tracks and Signs 

Figure 3. Tracks of a red squirrel. They are similar in structure to gray and fox squirrels.  Image by Dee Ebbeka.