North American porcupine (Erethizon dorsatum) Packy Savennas/ greekmountainman.com
Journal Articles
Death of gray wolves, canis lupus, in porcupine erethizon dorsatum, dens in wisconsin. Wydeven AP, Boles SR, Schultz RN, Doolittle T. The Canadian Field-Naturalist. 2003
Traumatic, degenerative, and developmental lesions in wolves and coyotes from Saskatchewan. Wobeser G. Journal of Wildlife Diseases. 1992 Apr