The breeding season for the Coues deer is about 6-8 weeks later than northern or eastern whitetail.  Breeding generally occurs from December to February with the peak usually in January.  Some breeding activity can occur in November and some even as late as March.  In November, bucks are generally found in small herds and can be seen sparring to establish dominance for the upcoming breeding season.  These sparring matches are generally very short-lived and mild. 

They are much less dramatic than the spectacular battles that can occur during the rut.  Bucks spend the breeding season searching for does in estrus (those ready to breed).  Females are receptive to breeding for only 2-3 days. Females that are not bred in their first estrus cycle may be bred during their next cycle about 26 days later.  Bucks can be very aggressive toward does during the breeding season.  I have seen them chase a doe in a frantic effort to keep them from running away.  They herd the doe much like a horse herds a calf or a sheepdog herds sheep, not allowing them to escape.  If there are other bucks present around the doe, the dominant buck will usually be closest to the doe and force the other bucks to stay in the periphery. Bucks are most vulnerable to hunters during the rutting period because they are much more active throughout the day and rather careless in their single-minded pursuit of females.  

Just as the breeding season for Coues is 6-8 weeks later than that for other subspecies of whitetail, the antler cycle is similarly delayed.  For Coues deer, antler growth happens from June-September.  During that time, the antlers are covered with "velvet".  After the buck has completed antler growth, the velvet dries up and is rubbed off (antler polish).  In Arizona, Coues deer typically polish their antlers from late September to mid-October.  Originally the antlers are white but become stained brownish from blood in the velvet and from the juices in the trees and bushes that the buck rubs his antlers against.

Antlers are then used during the breeding season to secure mates through displays and fighting with other bucks.  After the breeding season, hormonal changes cause the antlers to drop off.  In Arizona, that antler drop typically occurs in April and May.  Growth of the new antler begins shortly after antler cast