I found 2 birds about 150 yards away and noted they were acting like a mated pair with one bird keeping watch while the other bird fed almost continually. I watched them with my scope and did not move for about 30 minutes waiting for them to get accustomed to me. Then the feeding bird came to the male and laid her head flat on the water. The male mounted with little of the aggressive roughness seen in Mallard couplings. After a bout of preening and bathing the pair flew to another wet area.