Carcasses of 13 Richardson's ground squirrels (Spermophilus richardsonii) cached during autumn by North American badgers (Taxidea taxus) in southern Alberta, Canada, were inspected to determine the capture and killing technique. Regardless of prey size (251651 g) or torpor status (normothermic or torpid), badgers killed ground squirrels with a single grasping bite directed dorsally or laterally to the thorax. The canines and third upper incisors of badgers generally bruised the skin without puncturing it, but caused extensive hematomas on the thoracic musculature and penetrated between the ribs, with associated breakage of ribs and hemorrhaging in the thoracic cavity. Internal organs and bones other than ribs were usually not damaged. Thoracic bites, rather than nape or throat bites, are used by several mustelids, including North American badgers, when capturing small prey (<10% of the predator's mass).