The following shows return flights at end of day. Downgrade is a little greater than appears. The both birds seemed to invest alot in slowing approach. In this intance exhibited very little trimmed out flight. Trimmed out means body is held in a more horizontal position and often results in a lot more speed and distance. Both birds are doing most of flight at about stall speed which is just under 20 miles per hour. I am pretty sure these guys are capable of flying nearly twice as fast as shown here which results in a very different flight profile.

http://youtu.be/kz5QjbQdVZU

Based on other observations in similar context the birds communicate vocally the intent to fly before doing so. The take great pains not to loose site of each other. The sexual dimorphism in coloration I think is a very important signal coming from flying birds.