University of Alberta
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| Tufted Titmouse (photo by W. Collette) |
Getting in touch with nature in an urbanized world can be as
simple as putting a bird feeder in your backyard. However, what are the potential
consequences of this act? Bird-window collisions are one of the largest threats
facing urban bird populations in Canada.
A new study out of the University of
Alberta engages citizen scientists to determine the effects of feeders on
bird-window collisions.
Despite the popularity of feeding wild birds, the effects of
bird feeders and year-round feeding on birds have not been well documented,
particularly in relationship to bird-window collisions.
"Improving the relationship between the general public and nature can
promote biodiversity and conservation. We are working to find successful ways
to reduce bird-window collisions, beneficial not only for birds but also for
the millions of people who feed them."
In Canada, it is estimated that up to 42 million birds die each
year from collisions with windows, with residential homes accounting for 90% of
building-related mortality.
Trials were conducted on 55 windows at 43
residences in Edmonton and the surrounding area.
Homeowners were asked to
search their study window daily for evidence of bird-window collisions.
Though
there were 94 reported collisions with the presence of a bird feeder, there
were also 51 collisions in cases when no feeder was present, meaning there is
no black and white answer.
Twenty-six of the windows never experienced a
collision during the study, showing that some houses are more at risk than
others, regardless of the presence of the feeder.
"We've determined that the presence of a bird feeder does
indicate collision risk, but there are other factors involved," says
Kummer. She notes that vegetation and house characteristics can also influence
whether a residence is likely to have a large number of collisions.
"The
general public enjoys feeding birds in their yard, but they want to know how to
do so safely. Homeowners can certainly reduce some window collision risk by
altering feeder placement."
The study builds on previous work at the University of Alberta,
well known for its conservation and biodiversity efforts. The paper was
co-authored by Kummer's graduate supervisor Erin Bayne, associate professor in
biological sciences at the University of Alberta. Bayne's research team focuses
on understanding the cumulative ecological impacts of human activities on
biodiversity.
The findings, "Bird feeders and their effects on
bird-window collisions at residential houses," were published this fall in
the journal Avian Conservation and Ecology.