Teasing Through the Fence.

Teasing Through the Fence.
The buck is trying to detect pheromones, indicative of estrus, by sniffing the vulva and possible vaginal secretions. The doe's behavior, standing near the fence and tail wagging, is strongly suggestive of estrus. The urine stains on the buck's beard and front legs indicate that he has been sexually aroused in recent weeks.

Smith MC (2006)