2010 Nesting Season - Biodiversity Centre for Wildlife Studies

Publications in Short
Each year thousands of articles on birds are
published in scientific journals and obscure
reports that most of us do not see. Many of the
papers are helpful to nest-finders to assist in
their search for nests and broods, to understand
the ecological associations of nesting birds, to
learn about adaptations of body structures,
and to better appreciate some of the problems
facing ornithologists and the dedication that is
required for their research.
We have listed a few articles below that
should be of interest to participants.
Coots Use Hatch Order to Learn to
Recognize and Reject Conspecific Brood
Parasitic Chicks
“Crazy as a Coot” may not apply considering
the recent findings by ornithologists Daizaburo
Shizuka and Bruce Lyon. The team studied
American Coot behaviour at Westwick
Lakes in the Cariboo region of the province to
determine how the species was able to foil other
coots that laid eggs in their nests and reject
imposters. They found that coots can actually
count their own eggs and reject others that are
laid in their nests by other coots. They can also
tell the difference between their own chicks and
imposters (Figure 146). They do this by learning
to recognize their own chicks each year by
using the first hatched chick as a template for
identification. If the chick is not their own they
will attack and frequently kill the intruder. The
researchers also learned that in an average
year about half of chicks in a brood will die of
starvation.
Nature 463:223-226, 2010.
Figure 146. A pair of nesting American Coots
can not only count their own eggs and know
when a neighbour has added extra eggs and
reject them but also will attack (and frequently
kill) foreign chicks if they hatch in their nest.
Elizabeth Lake, BC. 7 July 2010 (Photo by
Brent Wellander).
Movements and Resource Selection of
Fledgling Goshawks in Montane Forests of
Southeastern British Columbia
Over the past decade, concern over the
impact of logging activities on Northern
Goshawk nesting habitat in mature to oldgrowth
forests throughout British Columbia
has been a growing concern to wildlife
managers. Most interest has been concentrated
on the area immediately surrounding a nest
site for the period of nest-building to fledging.
The present study, by W. Harrower, K. Larsen,
and K. Stuart-Smith, added a new dimension
to management plans that included the little
known period from fledging to post-fledging
and independence.
In southeastern BC, radio-tagged fledgling
Northern Goshawks remained within 298
metres of the nest during the first 21 days
and within 525 metres between 21 days and
dispersal from the territory. Each post-fledging
area averaged 36.7 hectares in size and juveniles
favoured forests 40 years
old with high crown closure and half of the
area should be forest >80 years old.
Journal of Wildlife Management 74(8):1768-1773,
2010.
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