We evaluated levels of body fat, body condition scores, live weight, and fetal rates of mule deer (Odocoileus hemionus) compromised by injuries from radiocollars and compared them to non-injured animals before and after those injuries had healed. Compromised animals had lower values for all parameters at the time injuries were discovered, and that pattern repeated itself 4 mo later when subjects again were examined. Investigators must consider ramifications of their activities for research subjects, as well as for research results.