Hi Tweets,

I had the good fortune of having a pair of Cooper's Hawks nest in the
woods behind my house on Kent's East Hill this spring. I first noticed
them about April 1 as they were vocalizing loudly and regularly from the
woods. They continued to do so daily until about April 20th or so,
after which they changed to vocalizing less often and usually only with
one or 2 notes. So it seemed to me at that time that they had set up
shop and were probably entering another phase in the nesting process. I
was never able to locate the actual nest, but it seemed to be about 50'
high in a douglas fir stand within the dense woods about 50' behind the
house.

I saw the first fledglings in and about the yard July 7th, although they
probably fledged a few days earlier and I didn't notice. One thing that
was particularly interesting to observe was that in the first 2 weeks or
so out of the nest, they showed their age by putting themselves in very
unhawk-like (not sure that's a word) situations - 2 on the fence, one in
the grass, one on the roof of the house, and one rooting around in a
very large shrub somewhat like a sparrow. They were quite wary though
as they would fly up (somewhat heavily) if anything disturbed them, but
they were also easy to observe regularly as they often perched in trees
on the edge of the woods. When the one landed on the roof, a
neighborhood cat began to stalk it (the section of roof it landed on is
fairly low, so it probably appeared to the cat as a possible catch if
the bird made a subsequent move to a lower level). At any rate, it
seems a domestic cat will stalk a bird of at least this size.

The point I took from all this is that, given the awkward situations in
which the fledglings sometimes placed themselves, the immediate post
fledgling stage is a particularly risky period for them.

It is very easy to keep track of the birds, even when not seen, as they
vocalize very regularly and in a voice very different from an adult.
Their voice is quite high pitched (maybe 6,000 Hertz or so) in contrast
to an adult. It starts out quite strong and then smoothly tapers off.
The number of fledglings is at least 3. Even though I never saw more
than 2 at any one time, their unique vocalizations in combination with
easy viewing made getting a fairly reliable count pretty easy.

Another point of interest was their pattern of dispersal from the
immediate area of the nest. The wooded area in which the nest is
located is probably 15-20 acres in size and is adjacent to a much larger
and well wooded section. About July 17th, the birds started to venture
further from the immediate area of the nest, with their vocalizations
increasingly being heard from the more distant and larger area. Even
today though, I heard and saw one juvenile in the vicinity of the nest
site. So, the family still seems to be operating as a loose functional
unit within a now larger area surrounding their original nest site, and
I would guess the young are still being provisioned by the parents
because they continue to use their juvenile vocalization.


Mark Johnston
Kent, WA
markjtn at earthlink.net