Copulation was observed on 4/24/12. The male is very slightly larger than the female, and very slightly larger. I have a very difficult time telling which is which, even when they're side by side.
0n 5/2, copulation was again observed; this was also the first date I observed incubation.
The nest is just above eye-level from the highest observation point I can find, so I was unable to see actual eggs.
On 6/6 I suspected that hatching was taking place, but I could not confirm hatching until I saw an adult feeding an unseen chick on 6/11.
Incubation (or brooding?) continued until 6/15, at which time I left town and did not return until 7/30. I saw no incubation/brooding behavior after 6/15.
I was able to confirm the presence of 3 chicks on 7/4.
The first chick fledged on or about 7/30; all three were definitely fledged within a week.
After mid-August I was never able to confirm the presence of more than 2 fledglings. I occasionally heard a high-flying calling bird that I thought might have been an adult, but this never happened when I could see more than one fledgling, so I can't be sure.
Like last year, 3 young were fledged, but one of those fledglings disappeared relatively soon, and I do not know the fate of those birds for either year. Both years, the 2 other fledglings stayed in the vicinity of the nest and were clearly feeding themselves successfully by fall.
A pair has nested in the area for multiple years, using the top of a very tall tree just north of the present site. Last year they spent some time working on the old nest but also trying out a new location, before evenually deciding on the new spot. They built the new nest on the top of a pair of old pilings, just 10-15' above "normal" river level. This nest is easily viewed from a well-used walking path, and many people enjoyed watching the progress of the pair. They successfully fledged 3 young. The nest had to be maintained constantly, and it began to disintegrate as soon as the young fledged. The young stayed in the area after fledging and after the adults stopped feeding them, using the nest as a feeding platform, but the nest was completely gone almost before the last fledgling left in the fall.
They've just returned this year, and today one bird was sitting on the old, tree-top nest while the second was laying the first sticks on top of the pilings.