The animal commonly referred to as the “striped gopher” is actually a species of ground squirrel known scientifically as the Thirteen-lined Ground Squirrel (Ictidomys tridecemlineatus). This small mammal is an opportunistic omnivore, meaning its diet is highly varied and adapts based on what is readily available in its grassland and prairie habitats. Its feeding habits combine plant consumption and active predation, allowing it to thrive across a wide geographic range in North America.
Primary Food Sources
The Thirteen-lined Ground Squirrel’s diet is composed of roughly equal parts plant and animal matter, showcasing its flexible strategy. Plant-based foods include green grasses, clover, roots, tubers, and the flower heads of various herbs. They are significant consumers of seeds and grains, favoring wild weed seeds, but they also exploit agricultural sources like corn, wheat, and cultivated fruits and vegetables.
The animal portion of the diet provides a substantial source of protein important for growth and reproduction. Arthropods form the bulk of their non-vegetative intake. These include grasshoppers, crickets, beetles, cutworms, caterpillars, and other insect larvae. The squirrels actively hunt these insects, which can constitute up to half of their total food consumed during the summer months.
Beyond insects, the Thirteen-lined Ground Squirrel occasionally preys upon small vertebrates and other ground-dwelling organisms. This includes earthworms, lizards, the eggs and young of ground-nesting birds, and small mice. They also scavenge on carrion when encountered, demonstrating their generalized approach to finding sustenance.
Foraging and Storage Behavior
Thirteen-lined Ground Squirrels are diurnal, foraging mainly during the warmest, sunniest parts of the day. They typically remain within a short distance of an escape burrow, constantly surveying their surroundings from an upright posture while searching for food. Foraging involves surface grazing for vegetation, digging into the soil to uncover roots and tubers, and actively chasing insects.
A distinguishing characteristic of their feeding behavior is the extensive use of internal cheek pouches. These specialized pockets allow the squirrels to quickly gather and temporarily store large amounts of food, such as seeds and grains. They then transport the food back to their underground burrows, minimizing their exposure to predators on the surface.
Once in the burrow system, the squirrels create underground larders, or caches, by storing the gathered food. These caches consist mainly of dry plant material like seeds and grass. They serve as reserves utilized during periods of low availability, such as inclement weather or immediately following emergence from hibernation in the spring. They typically do not cache animal matter.
Water Acquisition and Seasonal Diet Shifts
The Thirteen-lined Ground Squirrel rarely needs to drink standing water, a trait adapted to its often dry, open habitats. It meets its entire hydration requirement through the moisture contained within the food it consumes. Succulent plant parts and the bodies of the insects they eat provide sufficient water for their metabolic needs.
The composition of their diet shifts noticeably as the season progresses, driven by nutritional necessity and food availability. In the spring and early summer, after emerging from hibernation, the diet is rich in protein from insects and fresh, green C3 vegetation. This high-protein intake supports the demands of reproduction and body tissue repair.
As summer moves into fall, the dietary focus changes to energy-dense resources in preparation for winter dormancy. They consume an increasing amount of high-fat and high-carbohydrate foods, particularly mature seeds, cereal grains, and C4 vegetation. This shift allows the squirrel to rapidly accumulate fat reserves necessary to fuel its body through the months of hibernation.