We happened upon this Belted KF pair flying from piling to piling and dock to dock near a pier across the tracks and street from our place in Tacoma, WA. We have seen the male and female frequently on our walks but this was special. Mostly if was the male chasing the female. Occasionally they roosted close together. This went on for over an hour! Initially we didn't have our cameras so we walked back to retrieve them and upon returning they were still at it. About 3 hours later we saw them again from our deck. I imagine the male was displaying horniness but ... Was fun. (P.S. found out this year that the female is the more colorful of the genders.)