|
"Lights
Out" Program in Chicago Saves Birds
For
several years, the City of Chicago and bird conservationists
have worked with building managers to lessen the risk the
city’s skyline poses to migratory birds (See "Lights
Out Downtown for Birds", CW, Winter ’01).
This
year, the program will distinguish between two different
types of buildings. The bright exterior lights of Chicago’s
tall buildings confuse nocturnal migrants that fly too close
to them, causing them to fly directly into the tall buildings.
In contrast, at buildings right along the edge of Lake Michigan,
it is thought that birds are killed at dawn as they fly
in looking for cover and crash into windows.
Field
Museum scientists Doug Stotz and Dave Willard have studied
bird kills at McCormick Place for years, and they also have
some data about bird kills at the Hancock Center. Stotz
reports that mortality of May and September migrants, particularly
warblers, is highest at the Hancock Center (and presumably
other tall buildings), while McCormick Place takes a higher
toll on the colder-season migrants (April and October),
particularly the many species of native sparrows.
Over
the course of the study, an average of 1,500 birds were
killed each year by flying into McCormick Place’s windows.
According to Stotz, that number was reduced by about 80
percent when indoor lights were turned off – proof
that the Lights Out program can save thousands of birds
every year.
—
Ken Wysocki
|
