The recent post on Bald Eagles and Red-tailed Hawks motivates me to report
an incident I witnessed near the runways at Sea-Tac Airport last week.

I was working the airfield and observed a second year Bald Eagle in
aggressive flight mode pursuing a juvenile (SY) Red-tailed Hawk across the
sky about 100' up. The Red made the mistake of trying to escape downwind in
a fairly stiff SW wind. It might have been wiser to try and escape upwind,
using its presumed lighter wing loading to its advantage. But...bad move by
an inexperienced bird.

The Bald Eagle easily caught the hawk in mid-air and carried it to the
ground right in front of us. I've been looking at raptors for awhile now and
was completely amazed to see this event. I have never witnessed this type of
behavior before. The Bald Eagle had the Red-tail on its back in some tall
grass and all we could see were both redtail wingtips pointed up towards the
sky. I felt certain that the eagle had killed and was now going to eat the
hawk.

However, after approximately 12 minutes, the eagle simply stepped off the
hawk and released it. The hawk jumped up, doing the best WTF I have ever
seen a bird do, shook its plumage and took off. The eagle gave chase once
more and easily caught the red-tail a second time. It looked effortless to
me.

The birds landed again and this time the eagle let the hawk go almost
immediately. I noticed that it kept looking at the hawks feet. I had also
noticed that when the hawk flew away, it held one leg down, obviously the
result of an injury. Seeing this, I realized that the eagle thought the hawk
had food and was trying to kleptoparasitize it. It apparently had no
intention of killing the redtail. It just wanted the vole or whatever.

In fact, as we drove closer to see if the hawk was OK, the eagle shot off
again at another flying laden SY Red-tail, and easily caught up to
it. However, this hawk wisely dropped the vole. The eagle flew down to the
ground, recovered the mammal and ate it on the spot.

The red-tail was disheveled but flew away easily. I saw it again the next
day and it was still flying well at that time, leg dangling.

What puzzles me is that the eagle was obviously hungry. It had a red-tail in
its foot which it could have easily killed and eaten but it didn't. Why not?

--
Bud Anderson
Falcon Research Group
Box 248
Bow, WA 98232
(360) 757-1911
falconresearch at gmail.com
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