Reported animal-vehicle crashes (AVCs) and deer carcass removal have been used to define the deer-vehicle collision problem, identify its locations of concern, and evaluate its countermeasures. However, it has been shown that AVC magnitudes can be dramatically different. This research quantifies and compares the magnitude and patterns of AVC and deer carcass removal data from Iowa. Differences in these characteristics can affect the results produced by these activities. The difference in the magnitude of these two databases is confirmed, and some of the factors that may affect the size of this difference are discussed. Visual and quantitative comparisons are completed by using summary measures, geographic information system plots, and generalized linear regression models with a negative binomial error structure. This modeling approach has not been applied in the past to AVC or deer carcass removal data. AVC and deer carcass removal prediction (not causal) models for rural two-lane and multilane roadways were developed. The similarities and differences in the AVC and deer carcass removal models are discussed and the implications of these differences described. The differences found make the choice of database used critical to AVC-related roadway development decisions and policies, countermeasure location identification, and interpretation of research results. The recommendations provided focus on how AVC or carcass removal databases, as they typically exist, might be used and what improvements might be made for a more well-defined collection and application of these data.