We were exploring an area about 25 km up-river from home and just as we got out of the car, there was a little flurry of activity in the shallow water. I managed to get a photo of one of about 8 or 10 common mergansers that were speeding along the treed and rocky shoreline. They were moving quickly, diving and bobbing and were around the corner and out of sight in a second or two. I see mergansers a few times a year but rarely get a chance to photograph them so I was happy with this lucky shot.
This info from the Cornell birding site describes their typical behaviour: "They may form flocks of up to 75 individuals. They often swim in small groups along the shoreline, dipping their heads underwater to search for prey and then diving with a slight leap. Often when one bird dives in a large group, the others follow the leader and disappear. They can stay under for up to 2 minutes, but they normally dive for less than 30 seconds."
