Squirrels are common sights in many backyards, but figuring out exactly what species it is can be tricky. There are several types of tree squirrels and ground squirrels found throughout North America, and they can vary greatly in size, coloration, and behavior. Identifying squirrels takes patience and a keen eye, but with a few clues like habitat, size, tail shape, tracks, and behavior you can determine what kind of squirrel is raiding your bird feeders. Let’s take a closer look at some of the most common backyard squirrel species and the best ways to tell them apart.
Tree Squirrels vs. Ground Squirrels
The first step in squirrel identification is determining whether you are dealing with a tree squirrel or a ground squirrel. Tree squirrels spend most of their time in trees and build nests out of leaves in the branches. Ground squirrels, as their name suggests, spend more time on the ground in burrow systems. Tree squirrels have long bushy tails, whereas ground squirrels have shorter tails with little to no hair.
Common Tree Squirrels
The three most widespread tree squirrel species in North America are the eastern gray squirrel, fox squirrel, and red squirrel. Here is a brief overview of each:
- Eastern Gray Squirrel – Medium-sized with predominantly gray fur and a large bushy tail. Native to eastern North America but introduced to other parts of the continent. The most common backyard squirrel over much of the eastern US.
- Fox Squirrel – Large tree squirrel with brownish, gray, or reddish fur. Most have a brown/gray mix of colors. Native to central plains and eastern/midwestern woodlands. Also does well in suburban settings.
- Red Squirrel – Smaller than gray and fox squirrels with distinct red fur over most of the body. Found across Canada, the northern US, and south in higher elevations. Specialized for coniferous forests.
Common Ground Squirrels
Ground squirrels are prolific diggers that excavate elaborate burrow systems. Here are some widespread ground dwelling species:
- Eastern Chipmunk – Small ground squirrel with distinct stripes down back. Lives in wooded and bushy areas in eastern/central North America.
- California Ground Squirrel – Brownish squirrel with small ears and a short tail. Digs burrows in open ground of the western US and Mexico.
- Thirteen-lined Ground Squirrel – Striped ground squirrel of central US plains. Spends much of its time above ground near its burrow entrance.
Identifying Tree Squirrels
When trying to distinguish between tree squirrel species, here are some key traits to focus on:
Habitat
Consider the types of trees and other vegetation present near where the squirrel is being observed. Gray squirrels and fox squirrels do well in deciduous forests and wooded suburban areas. Red squirrels are more associated with coniferous forests dominated by pine, fir, and spruce trees.
Size
The three tree squirrels differ noticeably in size. Red squirrels are the smallest at 9-12 inches long. Gray squirrels are medium-sized at 15-20 inches. Fox squirrels are the largest at 18-27 inches long from head to tail.
Colors and Markings
The colors and markings are perhaps the most obvious visual clue for squirrel identification. Grays are predominantly gray all over the body and tail. Fox squirrels show a mix of gray, brown and tan. Red squirrels are reddish-orange over most of the body with some black and white accents.
Ears
Subtle ear differences exist between gray and fox squirrels. Gray squirrel ears are smaller and more finely haired. Fox squirrels have noticeably large ears that are fringed with white hairs.
Tracks
Tracks and footprints can be another diagnostic trait, though clear prints are not always available. Gray squirrels have smaller footprints around 2 inches long. Fox squirrels have larger prints up to 2.5 inches long. Examine substrate like snow or mud near trees for impressions.
Behavior
There are some subtle behavioral differences to look for. Gray squirrels are more solitary and do not tolerate crowding with other squirrels as much. Fox squirrels are somewhat more social and tolerant of one another. Grays also tend to be more active during mornings and afternoons. Fox activity peaks during mid-morning then increases again late afternoon.
Key Traits of Ground Squirrels
Ground squirrels share some common traits but also have distinctive features worth noting:
Burrows
All ground squirrels are dedicated burrow excavators. Look for holes approximately 2-3 inches in diameter in open ground. Mounds of loose soil also indicate active burrowing. The eastern chipmunk digs relatively simple burrows, while California ground squirrels construct more complex multi-entrance tunnel systems.
Body Size and Tail
Ground squirrels also differ in size. Chipmunks are quite small at 7-9 inches total length. California ground squirrels are one of the larger ground squirrels at 15 inches long. Tails help differentiate them as well. Chipmunks have a long slender tail. In contrast, the California ground squirrel has a much shorter tail relative to its body size.
Stripes and Coloration
Eastern chipmunks are easily identified by their distinctive striping pattern down the back and head. The thirteen-lined ground squirrel has stripes as well, but they form more distinct spots along its sides. California ground squirrels have drab brownish-gray fur all over.
Behavior
Behaviorally, eastern chipmunks are quite skittish and seek cover or run to their burrows when alarmed. California ground squirrels are more social near their burrows and watchful but slower to flee from people approaching them.
Other Clues for Squirrel ID
Here are some additional things to look for when trying to identify backyard squirrels:
- Noises – Squirrels make different types of squeaks, growls, chirps and chatters that can help distinguish species.
- Feeding signs – Look for chewed pinecones, empty bird feeders, and caches of buried food like nuts to infer the possible culprit.
- Habituation – How comfortable squirrels are around people. Red squirrels tend to be less habituated than grays and foxes in suburban settings.
- Nests – The types of nests or dreys squirrels build provide clues. Gray squirrels make large leaf nests. Red squirrels build smaller twig nests.
- Time of activity – Chipmunks are most active mid-morning. Fox and gray squirrels peak mid-day. Ground squirrels become active a couple hours after sunrise.
- Location – Whether they are frequenting the ground or trees more. Tree squirrels do come down but not for extended periods.
Conclusion
Identifying backyard squirrels takes patience and knowledge of subtle traits like size, tail shape, and behavior tendencies. Tree squirrels like grays, foxes, and reds have noticeable physical differences in coloration, ear tufts, and footprint size. Ground squirrels can be distinguished by tail size, stripes, and burrowing activity. Being observant of activity patterns, feeding behavior, and nests can provide additional clues to confirm squirrel species. With practice, you will soon be able to tell at glance just what kind of squirrel is cavorting in your yard.
| Squirrel Type | Key Identifying Traits | Typical Habitat |
|---|---|---|
| Eastern Gray Squirrel | Medium-sized, predominantly gray fur, small rounded ears | Mature deciduous forests and wooded suburbs |
| Fox Squirrel | Large, brownish-gray fur mixed with tan/orange, large tufted ears | Oak or pine forests, wooded urban areas |
| Red Squirrel | Small, distinct reddish body, small rounded ears | Coniferous forests dominated by pine, fir, spruce |
| Eastern Chipmunk | Small, black and white striped back/head, small rounded ears, long tail | Forest edges, bushy meadows, parks |
| California Ground Squirrel | Medium-sized, drab gray fur, short tail | Grasslands, fields, roadsides, disturbed open ground |
