Scavenging is often neglected as a source of bias when determining causes of mortality and collecting mortality-related habitat information. The use of mortality-sensing radio-transmitters has greatly increased our understanding of animal survival. However, the potential of lag-time in recovery of carcasses and subsequent determinations of cause of death are seldom addressed. Motion created by feeding predators and scavengers can delay pulse switchover and prolong recovery. We determined the influence of temperature, forest stand type, overhead cover, and carcass condition on scavenging rates, displacement patterns, and habitat sampling biases at perceived kill sites for ruffed grouse (Bonasa umbellus). We documented carcass disturbance, scavenger species, and displacement distances for 64 carcasses. Mammalian scavengers disturbed 42 of 64 grouse carcasses. Scavenger species identified included mice (Peromyscus spp.), flying squirrel (Glaucomys spp.), cottontail rabbit (Sylvilagus floridanus), Virginia opossum (Didelphis virginiana), raccoon (Procyon lotor), long-tailed weasel (Mustela frentata), bobcat (Lynx rufus), eastern coyote (Canis latrans), and common raven (Corvus corax). Air temperature and carcass condition were the dominant factors associated with scavenger disturbance of grouse carcasses. Mammal scavenging activity increased during warmer temperatures, and mock avian kills were scavenged more frequently than whole carcasses. Potential overestimation of mammalian-caused mortality may result from scavenging, especially when ambient air temperature is warmer and carcasses have been previously fed upon.