[mou] Hawk consensus by request

[Thomas Maiello]

I was asked to share what I got for info on my Cooper's Hawk info  
request so I am compiling the best and greatest hits for your pleasure  
reading.

This is what I got so far.  Very interesting.

Thomas: Cooper's Hawks have nested in our backyard pines several  
times, though not recently. They do most nest construction early in  
the morning, and are amazingly sneaky about their coming & going,  
although I have seen them drop from the nest site down to our lawn to  
fetch a stick. After egg-laying they are extremely secretive. The  
incubating bird manages to lie so flat in the nest that it is  
difficult to see even the head or back. Sometimes the only evidence of  
the bird on the nest is the tail projecting out over the nest. After  
hatching, of course, they come & go frequently & generally are more  
obvious. Their call/scold is a "cack-cack-cack," sometimes muted. Fly- 
by crows get an aggressive response from the COHAs. Climbing to band  
the nestlings elicits extremely aggressive response from the adults,  
including talon "scratches." Helmet, leather jacket & gloves  
recommended. Or just leave them alone. Fred Lesher, LaCrosse, Wis.

Thomas

In the past 2-3 weeks, at two different sites,  I have watched male
Cooper's Hawks make numerous trips with sticks to nests (one in my
backyard) while a female was perched nearby. Both turned out to be
one-day-wonders, as neither site was used. From my experience, males
probably make an attempt to select the nest site which then must be
approved by the female. Thus, presumably potential sites may be  
involved. I
was disappointed my yard was not chosen.

The BNA account on COHA states the following:

"Nest Construction

Male does most nest building, although female occasionally brings in a
stick or a large flake of bark. Male gathers most nest material within a
100-200 m area of the nest. Nest visits by male are brief; associated  
with
nervous, jumpy behavior. When the nest is near-completion, female may  
use
it as a feeding platform (Meng and Rosenfield 1988)."

Hope this is useful.

James Mattsson

Thomas--I am not an expert on any kind of hawks nest building, just  
wanted to share my own spottings.  There is a spot along my route to  
work that has a hawks nest visible until the leaves fill out on the  
trees.  It is one of those 'merge into the turn lane, look quick over  
to the right, see what is happening today' observation points, nothing  
I can really get into details with.  I saw for several Springs a hawk  
on the nest, occasionally spotted a pair, sometimes smaller heads  
peaking over the top.  Then one year it was left unoccupied.  The next  
Spring it hosted a family of Great Horned owls to my delight, although  
my views were so limited.  Then nothing again.  This Spring I watched  
anxiously to see if there was any activity at the nest, and one day  
was rewarded to see a hawk (red tailed?) adding a stick to the nest.   
The nest seemed tended to, repaired after a year of laying empty.  I  
thought great--next generation occupants!!  Then nothing.  No visits,  
no anything at the time I traveled by.  The nest seemed to just lay  
there.  Within the last week I saw again a hawk placing a stick on the  
nest.  I have been wondering the same things that you have: are they  
like wrens that build mulitple nests to impress the girlfriend, then  
let her choose the home they will live in?  Do they build nests  
whether they have a mate or not this season?  Is the colder weather  
affecting their decision to lay eggs if they are paired up?  It is a  
big 'hmmm.....'  Anyway, it gives me something to ponder on the short  
trip to work every day.  Cindy in N. Mankato


Thanks everyone for asking.

Thomas Maiello
Angel Environmental Management, Inc.
Maple Grove, MN