One of the first Duke University buildings to be certified as “green” appears to be causing more bird deaths than any other building on campus.
The Fitzpatrick Center for Interdisciplinary Engineering, Medicine and Applied Sciences caused 85 bird deaths during three 21-day surveys during the peak migration period spanning 2014-15.
A separate, unpublished Augustana College study places Duke highest out of 45 campuses in number of bird collisions. The campus is located along the Atlantic Flyway, a migration route.
The first recorded death was a fox sparrow, a stout red and brown bird most often seen kicking up leaf litter, searching for insects or seeds. Cedar waxwings – a sleek, fruit-eating species with tawny feathers and sharp black mask – have also been collected. Other species affected include ruby-throated hummingbirds, goldfinches, downy woodpeckers and kinglets.
Scott Winton, Duke Ph.D. candidate and a leader of Duke’s Bird Window Collision Project, said environmental certification programs such as LEED, or Leadership in Energy & Environmental Design, encourage using natural light to reduce energy use.
Nicolette Cagle, a lecturer at the Nicholas School of the Environment, supervised the bird-collision surveys. She said the seven buildings in the surveys were chosen according to methodology used by Augustana College researchers in their nationwide project and did not originally consider environmental certification or “green” design as a factor.
“Because these energy-efficient buildings often have requirements for ‘green views’ and natural light, they often have high glass proportions,” Cagle said.
She and Winton said the data only suggest a connection. Cagle also noted that Duke is located in a forest and surrounded by good bird habitat.
Steve Hager, an Augustana professor involved with the study, said in an e-mail there is a strong correlation between bird deaths and buildings with lots of glass.
“Research we published in 2013 ... strongly suggests that the number of bird-window collisions is super high at buildings with high amounts of sheet glass,” he said in an email
Windows are no friend to birds.
The glass between an average house cat and the birds outside offers less protection than it may seem. A study in Nature Communications in 2013 said house cats kill 1.4 billion to 3.7 billion birds per year, but the American Bird Conservancy estimates 1 billion birds die annually due to collisions with windows. The conservancy also estimates that wind turbines across the United States killed 573,000 birds in 2013.
Natalia Ocampo-Peñuela, a Duke Ph.D. candidate and leader (with Winton) of the Bird Window Collision Project, said administrators have been open to incorporating architectural reforms. She said the Penn Pavilion, almost entirely made of glass, was fitted with etched panes and saw only two collisions last year.
Two possible measures are being considered for existing and future structures. One, covering the glass with UV-reflective film, would make windows opaque to birds, but not to humans. Another, “fritting,” would make windows visible by etching a pattern into the panes.
“(The administration is) very interested in retrofitting the engineering building,” Ocampo-Penuela said.
“Sustainable energy should be sustainable with the life around you,” she said.