Pronghorn buck chasing doe, midsummer?

Paul in Idaho

Well-known member
Aug 9, 2012
Southwest Idaho
Twice this summer I have been watching herds of antelope when a buck has singled out a doe and chased her full speed. These weren't brief chases, either. They looped through the herd a few times, with the other members stepping out of the way. One time the buck chased the doe in a straight line for close to a mile before I lost sight of them in a shallow canyon.

The rut is still several weeks away. Do any of you know what might have caused these chases?