Details
The wildlife management units (WMUs) used to structure Oregon's big game hunts and collect population data were created in the 1950s. Based on conventional wisdom about animal distributions and movements at that time, WMUs were used primarily for managing hunter distribution. Easily recognized landmarks and socio-political boundaries were used as boundaries for ease in identification.
Extensive research using GPS-collared deer has shown that WMUs rarely contain all the resources a deer herd needs in a year. For example, many animals within a herd spend summer/early fall (when they are harvested by hunters) in different WMUs than during winter (when they are counted by ODFW).
Based on the movements from over 1,400 mule deer collared in recent years, ODFW has identified 22 distinct mule deer herd ranges in eastern Oregon. A mule deer "herd range" includes the entire area a herd uses in a year, including summer ranges, winter ranges, and the migration corridors between them. These ranges now form the basis for ODFW's mule deer monitoring and management, including harvest management.
ODFW's improved, stronger population models now integrate multiple data streams, including herd composition (buck and doe ratios) and abundance data. To function properly, these models also require accurate harvest data to be collected within a herd range, which is difficult with the current WMU hunt structure.
To address this misalignment, ODFW will transition mule deer hunting from WMUs to new Deer Hunt Areas within herd ranges in 2026. This change will better align hunting effort and associated harvest with Oregon's mule deer populations and management goals, improve monitoring of population trends, and allow for quicker management responses/accurate evaluation of management actions.