From BNA:
Causes Of Death
Predation, especially by raccoons (e.g., Schriver 1969
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib112>)
and Great Horned Owls (Rosenfield 1988
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib094>),
probably most widespread and important cause, but largely unquantified.
Nestling death or nest destruction by exposure (Meng and Rosenfield 1988
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib067>),
windstorm, or logging (Reynolds and Wight 1978
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib090>
, Rosenfield and Anderson 1983
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib096>),
and starvation of youngest, smallest sibling (Asay 1987
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib002>,
RNR and JB) also known or assumed. Disturbance by humans, unless prolonged
(> 30 min), unlikely to bring desertion of eggs or young (RNR and JB).
Falconers take small numbers of nestlings (Asay 1987
<http://bna.birds.cornell.edu/bna/species/075/articles/species/075/biblio/bib002>
).
On Thu, Jul 14, 2016 at 10:57 AM, Margie Paris <margieparis1@xxxxxxx> wrote:
Dear OBOL,
I’ve been watching a Cooper’s Hawk nest in Eugene for the past month, and
it has now possibly failed. The female is a first-year mother in non-adult
plumage. Having not seen any feeding activity for the past two days, I
scouted under the nest tree this morning and found a dead chick. I’ve
attached a photo to my eBird checklist (see below for link). The chick’s
body appears to be whole.
Although I can’t see any indication of remaining chicks (originally, there
were three) from my spotting scope station upstairs in my house, looking up
from below the nest I can see a white form in the nest that may be a chick,
but I haven’t seen it move. Meanwhile, the female sat on her nearby
preening tree for over 3 hours this morning — unusual inactivity it seems
to me.
Last night my son spotted the female drinking out of a puddle in front of
our house, and last week a neighbor had a similar report. Does this suggest
that she has not been getting adequate prey? My sense is that the male has
not been bringing food for some days, but that impression could simply be a
result of my inattention or his stealth. In the early stages, hand-offs
between the male and the female were visible and audible from trees within
a couple hundred yards of the nest tree.
Would love info.
Best,
Margie
Margie Paris
2394 Charnelton Street
Eugene, Oregon 97405
(541) 914-9356
margieparis1@xxxxxxx
Begin forwarded message:
*From: *ebird-checklist@xxxxxxxxxxx
*Subject: **eBird Report - 2394 Charnelton, Eugene, OR, Jul 14, 2016*
*Date: *July 14, 2016 at 10:46:06 AM PDT
*To: *margieparis1@xxxxxxx
2394 Charnelton, Eugene, OR, Lane, Oregon, US
Jul 14, 2016 7:30 AM - 10:30 AM
Protocol: Stationary
1 species
Cooper's Hawk (Accipiter cooperii) 1 Female sat on preening tree for
over 3 hours; nest seemed inactive; I found one chick dead on ground about
10 feet from nest tree; looking from underneath, I can see white in nest --
possibly another chick or two, but there appears to be no movement. I have
seen no feeding in past two days. Michael and a neighbor saw female
drinking from puddle on street several times in past week; perhaps she has
not been feeding adequately?
View this checklist online at
http://ebird.org/ebird/view/checklist/S30682051
This report was generated automatically by eBird v3 (http://ebird.org)
