North American badgers are solitary, semifossorial mustelids present throughout central and western North America. Adaptations, both morphologically and behaviorally, allow badgers to excavate soil rapidly and efficiently. North American badgers have extremely acute auditory and olfactory senses, capable of hearing and smelling through considerable soil depths (Minta and Marsh 1988). Consequently, they are effective predators of ground squirrels, pocket gophers, burrowing owls, kangaroo rats, voles, and various mouse species (Eldridge 2004). As opportunistic carnivores, badgers forage on a range of vertebrates and invertebrates, including insectivores, lagomorphs, reptiles, amphibians, birds, eggs, and arthropods (Minta and Marsh 1988). While foraging for burrowing prey, badgers excavate large volumes of topsoil and produce large pits and distinctive fan-shaped mounds at burrow entrances.
Regardless of prey density, badgers typically predate during times of prey vulnerability, specifically hibernating individuals and immobile young (Michener 2000). Studies indicating the presence of caching by badgers describe some astonishing behaviors. Ground squirrel carcasses were always cached individually, regardless of numbers of captures during the same night, and only one carcass was retrieved per night, regardless of the number of available carcasses. Badgers always retrieved carcasses sequentially relative to time since caching, despite other cachings of larger animals that were more valuable relative to energy content. Additionally, badgers cached carcasses in a curled head-to-tail conformation, reminiscent of sleeping or hibernating ground squirrels, although the tightly folded posture is not one adopted naturally by carcasses (Michener 2000). As badgers are opportunistic foragers, they likewise demonstrate behavioral flexibility when hunting, supplementing the customary technique of excavation with plugging of burrow entrances, ambushing, and hunting associations
Example of a maternal female badger hunting a black-tailed prairie dog via excavation:
At 12:12, a female badger was observed slowly emerging from her den. She then walked westward sniffing burrows. She oriented herself toward a tonically calling prairie dog and sprinted to its location. The prairie dog entered the burrow. The badger sniffed the burrow and then began a frenzied bout of digging at 12:14. During excavation, a burrowing owl attacked the badger, diving and striking her on the back 3 times before retreating to a burrow located near the western periphery of the prairie dog colony. Periodically, the badger emerged, shook, perhaps to dislodge soil from her fur, and looked toward her den. The badger stopped digging at 12:51 and assumed a sprawled out position, presumably to rest. About 2 minutes later, the badger continued to excavate the burrow. At 13:20, the badger emerged, carrying an adult prairie dog” (Eads and Biggins 2008).