Today at 11:15 there were scads of scaup in a raft just N of Chimney Point.
I will estimate 600 ducks or more. The N wind was blowing hard, ice pellets
were driving horizontally, and the waves were about 2 feet. The ducks kept
taking flight and relanding, then taking flight again and landing again only
a few hundred meters from where they took off. There was no visible human
disturbance to cause this behavior.
Why would the ducks keep repositioning, since it seemed like the wind and
waves were equally severe in all the locations they landed? They could
have flown under the bridge and rested in the much calmer water S of the
bridge. I did not notice feeding behavior.
Also, why do many of the diving ducks like scaup and goldeneyes raft up so
close to each other? Does this allow them to share some body heat? Does
the presence of so many ducks so close together dampen the waves, like lily
pads on a pond will do? Or does this make it harder for a predator like an
eagle to single out one individual to pick off?
Why do they often form a long line, in today's case, stretching from E to W,
maybe 3-5 ducks deep? This would seem to maximize the force each duck
received from the wind and waves, since the wind was from the N mostly. A
circle or oval would seem better, and they did that, too, but often were
stretched way out in one or two lines.
Thanks for your thoughts and answers about diving duck behavior.