Despite no mention of abnormal coloration in bighorn sheep (Ovis canadensis) in two earlier reviews addressing that subject, leucism, piebaldism, and melanism do occur in that species. Presented herein is a compilation of observations of abnormally colored bighorn sheep (Ovis canadensis) assembled with information obtained from personal observations and the use of on-line literature search services, other on-line searches, private interviews, and a questionnaire. The majority of abnormally colored bighorn sheep have been described as "white" or "albinistic". Review of images provided by respondents, however, verified that the majority of such reports were of leucistic individuals. "White" or leucistic bighorn sheep have been described from 23 specific geographic areas distributed among one Canadian province, one state in Mexico, and seven of the western United States; reports of piebaldism or of melanism are much less frequent.