An evaluation of the Michigan Department of Natural Resources' white-tailed deer (Odocoileus virginianus) field survey methodologies

The Michigan Department of Natural Resources (MDNR) needs reliable data for public accountability and sound scientific management of the state's white-tailed deer (Odocoileus virginianus) herd. Three white-tailed deer field surveys were examined to evaluate the quality of the data collected. The biophysical data (biodata) collected from harvested deer brought to voluntary check stations provides the largest available source of data on Michigan's deer herd, but biases, errors, and insufficient data limit the use of the biodata. However, the biodata can be used in the sex-age-kill estimates of population size, or to develop indices of herd health, track herd or harvest composition, and compare the herd composition of different years or geographic areas. The lactation data do not provide an estimate of annual recruitment, but they can be used to develop an index or minimum estimate of reproductive success. The inconsistent manner in which the winter severity index (WSI) data are collected prevents the index from being a useful tool with which to predict winter mortality or yearling beam diameters. Standardizing the collection process or developing an alternate WSI could make such predictions possible. By improving the quality of the data collected in the field surveys (e.g. by increasing the number of check stations or other methods), the MDNR will be better able to manage Michigan's deer herd and will increase public confidence in their management decisions.