Mule Deer Rut

 

The mule deer rut is triggered by a decrease in the photoperiod. A hormone called melatonin is produced in response to increased darkness. When the melatonin reaches a certain level in the bloodstream, it induces estrus. Most does are bred in their first cycle. However, deer can continue to cycle, every twenty-eight days, until there is enough daylight to reduce estrogen levels.

Learn more on what triggers the rut 

Jim
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