Subject: [Tweeters] PEREGRINE FALCON (PEFA) and COOPER'S HAWK (COHA)
Date: Sep 4 12:19:58 2007
From: johntubbs at comcast.net - johntubbs at comcast.net


Hi All,

This morning I witnessed an interesting interaction between a juvenile COHA and an adult female PEFA. When I woke up this morning and looked out the window to see what was out and about already, I saw a raptor silhouette in the snag tree about 150 yards up the golf course fairway that is used periodically by various raptors as a hunting or resting perch. Every couple months a PEFA (on several occasions, two) will show up in this tree (probably more frequently than that, but I'm often not home to see it). The binocs confirmed Peregrine and so I grabbed my scope and decided to watch until the bird left, no matter how long that took.

It was quickly apparent that she was looking for a meal, as the head movements were frequent and searching (and the crop was not puffed out). She made one quick flight away from my vantage point and behind trees, then returned shortly empty-handed and continued searching intently. Then, an accipiter flew in from the side and did a half-hearted harrassing pass at the PEFA and landed in a tree no more than 10 yards from the PEFA, who hardly appeared to have noticed. The accipiter was a juvenile COHA, leaving me to wonder if Junior might be about to find out he had been seriously foolish. My wife had joined me by now and verbalized what I was thinking, "Do Peregrines eat Cooper's Hawks?" Whereupon the Cooper's made another fly-by of the PEFA and landed in a tree about fifty yards away.

A few minutes later, the PEFA flew off quickly in the direction of Fall City and the Snoqualmie Valley. Following 'Bud's Law' that states "Never take your eye off a flying falcon!" I watched until she was out of sight but nothing exciting happened.

I wonder what the COHA's purpose was...? Harrassing (the passes didn't seem to be particularly energetic)? An invitation to engage in a dogfight (supposedly PEFA's will do this on migration with other species of raptors)? Or, perhaps more likely, a curiously naive youngster not realizing what might happen as a result? I would have to think that a first year COHA would be no match for a PEFA who was intent on inflicting damage in an aerial duel - anyone out there with any data that relates?

John Tubbs
Snoqualmie, WA
johntubbs at comcast.net
www.tubbsphoto.com