Swans at Monticello -- part 2

I took this shot because I liked the colors and textures.

About 9 a.m. the Swans started to fly about more.

I think these geese were upset because Les & I were paying too much attention to the Swans.

So I took this shot of a goose.

Les asked, "What are all those ducks with the white on them that won't come near us?" They were flying in small flocks way on the other side of the river. I replied, "I don't know, but we'll find out when we get home." When some landed, I took this shot. It turned out they were Common Mergansers. Although I had my binoculars with me, I don't usually use them when taking photos since I figure if I can't see the bird clearly without binoculars, I won't get a good shot.
It was getting near 10, and we were both cold from the breeze from the river -- so, we headed to a MacDonald's near the freeway for breakfast & hot chocolate. (Thank you, Les!) It took us nearly an hour to warm up.

When we got back, I noticed all of the American Coots. I've never got a satisfactory picture of one; the feathers around the head must be fuzzy since they do not reflect any light -- the heads look darker than the rest of the body. And, unless the light hits their eyes at the right angle, the eyes just disappear and can't be seen in a photo. These are a couple of my best shots to date.

Crash landing!

Since it was getting near noon, we decided to call a halt to our visit. As we were putting away our gear, we noticed two raptors flying very high in the sky. This is a (poor) shot of one of them. I've poured over Sibley, Natl. Geographic, and Kaufman's -- I still can't identify the bird -- juvenile Bald Eagle, maybe? -- Swainson's Hawk? Someone have an idea?
Most of today's shots were taken with my 400mm lens + Canon's 1.4x converter. I realize now that what I really need (want?) is Canon's 500mm f4.0 lens with image stabilization. But the cost of about $5,000 is slowing me down -- plus the concern about the weight (8.4 lbs + camera + tripod). On our Nebraska trip, I held Stan's 500mm lens and it didn't seem too heavy -- but that was just holding it for a little while -- I would be using it trekking through Springbrook or Wargo for 3 to 4 hours at a time. Anyone have any leads on a used one?
Maybe I'll wait for reports on Sigma's new 150-500mm lens. It has image stabilization and weighs only 4 lbs., but at 500mm the f/stop is 6.3. Decisions -- decisions!
All in all, it was a good morning -- especially as I look out the window and realize I have to plow out my driveway.