Roaring Fork Valley Phenology | November 11, 2013

---

Mule deer Odocoileus hemionus have been the focus of my family’s wildlife watching over the past week. They have been frequently seen along the Rio Grande Trail and at Hallam Lake as the rut (mating season) approaches. On November 3rd these bucks were sparring in the yard. Later the same day the bigger buck was thrashing willows. Things are heating up. 

Sparring strengthens neck muscles, improves agility, and releases aggressive tension. Overall it establishes dominance which reduces the amount of real fighting between bucks as the rut starts. Though the males are making a spectacle, does initiate the rut as they go into estrus. 

So at this time of year in Aspen, where all of the leaves are off of the trees, and the ground is beginning to freeze, deer will begin to mate. We observed deer mating behind the house on November 23 last year and on November 17 in 2011. After a gestation period of around 200 days, fawns are born. My family will have our eyes out in the preserve mid-June.

 

~ Jim Kravitz, Director Of Naturalist Programs