The leading cause of death among humans is heart disease.

However, among birds, the most prominent causes are window collisions.

“Birds see the reflection of the landscape in the window and, thinking that it’s more open space, they collide with it,” Elizabeth Tanner, senior biology major at the University of Wisconsin-Platteville, said.

As part of a national study, Tanner and other UW-Platteville students investigated the factors that lead to detrimental window collisions.

“For 21 days, from September to October, we surveyed six buildings of various sizes and surrounding vegetation,” James Nooyen, senior biology major and co-leader of the research, said.

Tanner and Nooyen counted the number of dead birds near Boebel Hall, Bridgeway Commons, the Children’s Center, Ullsvik Hall, Pickard Hall and a private residence in Platteville.

The students compared the window area, size and surrounding vegetation of each building in order to determine which factors heavily contribute to the collisions.

“We hope to discover what we could do to decrease bird-window collisions in new and old buildings,” Nooyen said.

In Platteville, the students found the bodies of seven birds near the surveyed buildings.

Steve Hager, professor of biology at Augustana College in Rock Island, Ill., designed a procedure requiring the students to search for birds within a six-foot radius around the buildings.

There are an estimated five million commercial buildings and industrial facilities in the United States.

“We also recorded the number of stories, floor area, window area and percent of surrounding vegetation. Each factor was analyzed with respect to the abundance of bird carcasses found for each building,” Nooyen said.

Ultimately, Boebel Hall was the most common building on campus regarding window collisions, providing for three bird fatalities, while Ullsvik Hall reported two deaths.

Next year, further research will be conducted at the same time and locations.

Although Nooyen will be graduating at the end of the spring semester, Tanner will continue the project by conducting next year’s data collection.

Researchers hope that their findings will have an impact on building design, which will potentially lower bird mortality due to window collisions.

The use of non-reflective screens in windows has been proposed as a possible solution, since windows’ reflective surfaces are considered to be one of the major contributing factors to bird-window collisions.

Urbanization is growing at a faster rate than the growth of human populations, and the bird-window collision research is important for understanding the ways in which building design can impact the ecosystems of cities and their surrounding areas.

The data collection on the UW-Platteville campus was funded by a PACCE grant, and Nooyen and Tanner will present their findings at Madison’s annual “Posters in the Rotunda” and the 13th annual UW-System Symposium for Undergraduate Research and Creative Activity at the University of Wisconsin-Milwaukee in April.