very dark hawk, Northern California (1 Viewer)

These aren't very good shots, but I'm a bit intrigued by a hawk I saw this morning at Coyote Hills, Fremont, California (east side of San Francisco Bay). This dark brown guy swept in and aggressively rousted the Northern Harrier (third pic, provided for scale) off of a rock by the water.

I suppose it's a very dark Red-tailed Hawk, but I would have sworn that the wings were all dark below when this guy flew off a moment later. For a moment I thought it might be a Golden Eagle, but I think it's too small, and the wings weren't plank-like like an eagle's. I think I just didn't get a good look at it as it flew off, and it's a Red-tailed. Any other possibilities?

I'd go with dark adult Red-tailed (and a nice looking Harrier in photo #3, of course).

It's probably the same Red-tailed Hawk as in this thread from Sunday:
http://www.birdforum.net/showthread.php?t=104152

Garrett Lau said:

It's probably the same Red-tailed Hawk as in this thread from Sunday:
http://www.birdforum.net/showthread.php?t=104152

Click to expand...

Hi Garrett, I bet you're right. It was a bit of an eyecatcher. Gail got a much, much better shot than I did!

Thanks, Robert, but I did better with the Northern Harrier before it flew off to its brief stop on the rock:

http://leahy.to/birds/northern%20harrier.html

He was posing right by the boardwalk for quite a while.