Over 60% of Wisconsin homeowners report regular squirrel activity in their yards, yet most can only identify one or two species correctly.
You’re likely sharing your outdoor space with far more squirrel diversity than you realize.
This guide reveals all seven types of squirrels in Wisconsin, giving you the knowledge to distinguish between each species and understand their unique behaviors.
Whether you’re a curious nature observer, dealing with backyard visitors, or simply want to appreciate Wisconsin’s wildlife diversity, you’ll discover identifying features, habitat preferences, and behavioral patterns that make each species distinct.
Eastern Gray Squirrel (Sciurus carolinensis)
The Eastern Gray Squirrel dominates Wisconsin’s hardwood forests and suburban neighborhoods. You’ll recognize these adaptable rodents by their predominantly gray fur with white underparts and bushy tails that appear silver-tipped in sunlight.
Key Identification Features:
- Length: 16-21 inches including tail
- Weight: 1-1.5 pounds
- Coloration: Gray with white belly, occasionally black variations
- Distinctive white eye ring
- Large, rounded ears
These squirrels prefer oak-hickory forests but thrive in urban environments with mature trees. Eastern Gray Squirrels are common in Wisconsin and often battle homeowners at backyard bird feeders, with natural favorites including acorns, walnuts, and hazelnuts. You’ll spot them most actively during early morning and late afternoon hours.
Wildlife Tip: Gray squirrels can leap horizontally up to 10 feet and vertically up to 5 feet, making them exceptional escape artists from predators.
Their intelligence makes them formidable problem-solvers, often outsmarting “squirrel-proof” bird feeders through persistent trial and error.
Fox Squirrel (Sciurus niger)
Fox Squirrels represent Wisconsin’s largest tree squirrel species, distinguished by their rusty-red coloration and impressive size. These robust rodents prefer open woodlands and park settings over dense forests.
Key Identification Features:
- Length: 20-25 inches including tail
- Weight: 1.5-3 pounds
- Coloration: Reddish-brown to gray-brown with orange-yellow underparts
- Prominent ear tufts in winter
- Large, muscular build
In Wisconsin’s western regions, fox squirrels typically display reddish-brown belly fur and brownish-gray back fur, sharing similar food preferences with gray squirrels including acorns, hickory nuts, and walnuts. Their size advantage allows them to access food sources smaller squirrels cannot reach.
Behavioral Differences:
- More terrestrial than gray squirrels
- Slower, more deliberate movements
- Less aggressive toward other squirrel species
- Prefer ground foraging over aerial acrobatics
Fox squirrels excavate numerous small caches throughout their territory, demonstrating remarkable spatial memory when relocating buried nuts months later.
American Red Squirrel (Tamiasciurus hudsonicus)
Red Squirrels bring fierce energy to Wisconsin’s coniferous forests. These compact, territorial creatures defend their domains aggressively while maintaining year-round activity levels that surpass other squirrel species.
Key Identification Features:
- Length: 11-14 inches including tail
- Weight: 7-8.8 ounces
- Coloration: Rusty-red upperparts with white underparts
- Prominent white eye ring
- Black lateral stripe during summer months
The most noticeable characteristics include the bushy, dark red tail with white outline hints and the thick white circle surrounding their black eyes. Their smaller stature compared to tree squirrels makes them easily distinguishable.
Territory and Behavior:
- Maintain middens (cone storage piles) up to 30 feet across
- Highly vocal with chattering calls and territorial warnings
- Active year-round, unlike some ground squirrel species
- Prefer spruce, fir, and pine forests
Red squirrels demonstrate remarkable industriousness, harvesting and storing thousands of pine cones annually. Their aggressive nature extends to chasing away larger squirrels from preferred feeding areas.
Northern Flying Squirrel (Glaucomys sabrinus)
Wisconsin’s Northern Flying Squirrels inhabit the state’s northern coniferous forests as nocturnal gliders. These specialized mammals represent one of Wisconsin’s more elusive species, requiring specific habitat conditions for survival.
Key Identification Features:
- Length: 10-15 inches including tail
- Weight: 2-6 ounces
- Coloration: Grayish-brown above, white below
- Large, dark eyes adapted for night vision
- Furry membrane (patagium) connecting legs
Northern flying squirrels are Wisconsin’s version of Rocky the flying squirrel, representing one of two flying squirrel species in the state and holding special concern conservation status. Their nocturnal habits make direct observation challenging for most wildlife enthusiasts.
Habitat Requirements:
- Mature coniferous or mixed forests
- Abundant snags for nesting cavities
- Lichen and fungi food sources
- Limited to northern Wisconsin counties
| Flying vs. Gliding Comparison |
|---|
| True Flight: Powered wing movement (birds, bats) |
| Gliding: Membrane-assisted controlled falling (flying squirrels) |
| Distance: Up to 150 feet between trees |
| Landing: Upward swoop using tail as rudder |
These remarkable mammals use their gliding ability to access food sources and escape predators while expending minimal energy during winter months.
Southern Flying Squirrel (Glaucomys volans)
Southern Flying Squirrels occupy Wisconsin’s southern deciduous forests, representing the smaller of the state’s two flying squirrel species. Their distribution creates a geographic division with their northern counterparts.
Key Identification Features:
- Length: 8-12 inches including tail
- Weight: 1.5-3 ounces
- Coloration: Brownish-gray above, cream-colored below
- Smaller than northern flying squirrels
- More prominent eyes relative to body size
These social creatures often share nest cavities during winter, with up to 20 individuals huddling together for warmth. Their diet consists primarily of nuts, seeds, fruits, and occasionally bird eggs or nestlings.
Distribution Patterns:
- Southern two-thirds of Wisconsin
- Hardwood and mixed forest preference
- Higher population density than northern species
- More adaptable to habitat fragmentation
Southern flying squirrels demonstrate complex social behaviors, including communal nesting and food sharing that helps smaller individuals survive harsh Wisconsin winters.
Thirteen-lined Ground Squirrel (Ictidomys tridecemlineatus)
Thirteen-lined Ground Squirrels inhabit Wisconsin’s prairies and grasslands, representing a completely different ecological niche from tree-dwelling species. These terrestrial mammals create extensive burrow systems throughout their territories.
Key Identification Features:
- Length: 6.5-12 inches including tail
- Weight: 4-9 ounces
- Coloration: Brown with 13 alternating light and dark stripes
- Short tail compared to tree squirrels
- Small, rounded ears
Seasonal Behavior Patterns:
- Spring: Emergence from hibernation, mating season
- Summer: Active foraging, territory establishment
- Fall: Intensive feeding, preparation for hibernation
- Winter: True hibernation lasting 6-7 months
These ground squirrels prefer short-grass prairies, agricultural edges, and maintained grasslands. Their burrow systems include multiple entrances, sleeping chambers, and food storage areas extending up to 20 feet underground.
Conservation Note: Habitat loss through agricultural intensification has reduced thirteen-lined ground squirrel populations in many Wisconsin counties.
Franklin’s Ground Squirrel (Poliocitellus franklinii)
Franklin’s Ground Squirrels represent Wisconsin’s rarest squirrel species, holding special concern conservation status due to declining populations. These prairie specialists require specific grassland conditions increasingly rare in modern Wisconsin.
Key Identification Features:
- Length: 14-16 inches including tail
- Weight: 7-20 ounces
- Coloration: Grayish-brown with yellowish underparts
- Longer tail than thirteen-lined ground squirrels
- More robust build than other ground squirrel species
The Wisconsin Department of Natural Resources encourages public reporting of Franklin’s ground squirrel sightings due to their special concern species status. These observations contribute valuable data for conservation management efforts.
Critical Habitat Requirements:
- Native prairie remnants
- Minimum 40-acre territory size
- Dense grassland cover
- Proximity to wetland edges
Current Conservation Status:
- Population decline exceeding 50% since 1980
- Habitat fragmentation primary threat
- Agricultural conversion reducing suitable habitat
- Climate change affecting hibernation patterns
Franklin’s ground squirrels demonstrate the longest hibernation period among Wisconsin squirrels, remaining underground from August through April in some years.
Identification Quick Reference Guide
Size Comparison (Largest to Smallest):
- Fox Squirrel (1.5-3 lbs)
- Eastern Gray Squirrel (1-1.5 lbs)
- Franklin’s Ground Squirrel (7-20 oz)
- American Red Squirrel (7-8.8 oz)
- Northern Flying Squirrel (2-6 oz)
- Thirteen-lined Ground Squirrel (4-9 oz)
- Southern Flying Squirrel (1.5-3 oz)
Activity Patterns:
- Diurnal (Day Active): Gray, Fox, Ground Squirrels
- Nocturnal (Night Active): Flying Squirrels
- Year-round Active: Gray, Fox, Red Squirrels
- Hibernating Species: Ground Squirrels
Habitat Preferences:
- Deciduous Forests: Gray, Fox, Southern Flying Squirrels
- Coniferous Forests: Red, Northern Flying Squirrels
- Grasslands/Prairies: Ground Squirrel Species
- Urban Adapted: Gray, Fox Squirrels
Common Identification Mistakes
Gray vs. Fox Squirrel Confusion: Many observers struggle distinguishing between these species in overlapping habitats. Fox squirrels show consistently larger size, more prominent ear tufts, and warmer coloration. Gray squirrels demonstrate more agile movements and prefer higher canopy levels.
Flying Squirrel Species Separation:
Northern and southern flying squirrels occupy different Wisconsin regions, but overlap zones create identification challenges. Northern species show larger size, grayer coloration, and preference for coniferous habitats versus southern species’ smaller size and deciduous forest preference.
Ground Squirrel Distinctions: Franklin’s ground squirrels exceed thirteen-lined species in size and show uniform coloration without distinctive striping patterns. Their conservation status makes accurate identification crucial for population monitoring efforts.
Supporting Wisconsin’s Squirrel Populations
Understanding these seven types of squirrels in Wisconsin enables better wildlife management decisions in your outdoor spaces. Each species contributes uniquely to ecosystem health through seed dispersal, soil aeration, and predator-prey relationships.
Wildlife-Friendly Practices:
- Maintain native tree species for nesting sites
- Preserve snags for cavity-nesting species
- Limit pesticide use affecting food sources
- Create buffer zones around prairie remnants
- Report rare species sightings to wildlife authorities
Observation Opportunities:
- State parks with diverse habitats
- University arboretums and nature centers
- Prairie restoration sites for ground squirrels
- Northern forests for flying squirrel habitat
Wisconsin’s squirrel diversity reflects the state’s varied ecosystems, from Lake Superior’s boreal forests to southern prairies. Your increased awareness helps support conservation efforts while enriching outdoor experiences through informed wildlife observation.
These remarkable rodents demonstrate adaptation strategies developed over thousands of years, each species perfectly suited to specific Wisconsin habitats. Whether you encounter the acrobatic gray squirrel in your backyard or catch a glimpse of the elusive Franklin’s ground squirrel in native prairie, you’re witnessing evolutionary success stories that continue shaping Wisconsin’s natural heritage.
