Prairie dogs are highly social, ground-dwelling rodents belonging to the genus Cynomys within the squirrel family. Native to the vast grasslands of North America, they range from southern Canada down to northern Mexico. The Black-tailed prairie dog (Cynomys ludovicianus) is the most widespread species, inhabiting the Great Plains. Understanding their diet is fundamental to their role as a keystone species in the grassland ecosystem.
The Core Foraging Diet
Prairie dogs maintain an herbivorous diet, primarily consisting of vegetation found across the plains. Their main sustenance comes from native short-grass species, such as blue grama, buffalo grass, and western wheatgrass. These fibrous plants provide the necessary bulk for their specialized digestive systems, which process high volumes of plant matter. During the summer, consumption rates can range from 30 to 100 grams of green forage per day.
Prairie dogs also regularly consume forbs, which are broad-leafed herbaceous plants like dandelions, clover, and prickly pear. Forbs contain higher concentrations of vitamins and moisture than grasses, making them a valued part of the daily intake. They consistently clip vegetation surrounding their burrow entrances, even if they do not consume it all. This action maintains low sightlines, allowing them to easily spot approaching predators.
Seasonal Shifts and Opportunistic Consumption
The prairie dog diet is dynamic, adapting to resource availability as seasons change. During the lush growth of spring and summer, they select the most succulent, nutrient-rich parts of plants, favoring tender shoots and leaves. As the weather turns drier in late summer and fall, their focus shifts to seeds and dry plant material, which are higher in calories and fat. This consumption change allows them to build fat reserves necessary to endure periods of reduced forage.
Prairie dogs are opportunistic eaters, supplementing their plant-based diet with animal matter. They occasionally consume invertebrates, such as grasshoppers and beetles. While animal protein constitutes a small fraction of their diet, it provides a concentrated source of protein beneficial for lactating females or during periods of low plant quality. When surface vegetation is sparse in the winter, they rely more heavily on subterranean plant parts, including roots and tubers, accessed through their extensive burrow systems.
Diet’s Role in Colony Structure and Survival
The management and consumption of food resources are intertwined with the social structure and survival of the prairie dog colony, or “town.” In species that undergo periods of dormancy, increased consumption of high-calorie foods in the fall facilitates fat storage for hibernation. Black-tailed prairie dogs, which remain active all year, rely on stored seeds and roots, in addition to foraging, to sustain them through severe winter weather when surface access is limited.
Foraging behavior reinforces the structure of the coterie, the family unit within the town, as individuals forage in close proximity. The need to clip vegetation to maintain clear sightlines necessitates coordinated activity, promoting vigilance and communication among the group. Prairie dogs obtain nearly all the moisture they need directly from the water content within the grasses and forbs they consume. This ability allows them to thrive in the arid grassland environment without needing to drink freestanding water.