Concerning new research suggests wind turbines could be harming vulnerable grassland birds.

Shifting to renewable energy sources has been a major focus of recent decades, but a recent study uncovered some unexpected consequences of supposedly eco-friendly machines, the Central Ornithology Publication Office reported.

The findings show wind turbines in Kansas are driving out breeding Greater Prairie-Chickens (Tympanuchus cupido) in the region. A team of researchers monitored prairie-chicken leks (mating sites) before and after the installation of wind turbines, and found the construction caused many leks within about four miles to be abandoned.

Leks are where prairie-chickens mate each spring. Over the course of five years, the researchers looked at 23 of these sites to determined how many male birds were present and how high their body mass was. The installation of the wind turbines proved to reduce both male presence and body mass. Lek abandonment was common in sites where there were seven or fewer males.

"To me, what is most interesting about our results is that we are now able to start putting different pieces of our larger project together to better understand the response of Greater Prairie-Chickens to wind energy development at our field site," said study co-author Virginia Winder. "We have found that both male and female prairie-chickens have negative behavioral responses to wind energy development. The data we collected to monitor this response have also allowed us new insights into the ecology of this species. For example, lek persistence at our study site depended not only on distance to turbine, but also male numbers and habitat."

The researchers recommend a halt in wind energy development in areas within about four miles of these crucial leks.

"It is critical to have rigorous evaluations of direct and indirect effects of wind energy facilities on species such as prairie-chickens," said grassland wildlife management expert Larkin Powell, who was not involved with the research. "The potential for trade-offs between renewable energy and wildlife populations on the landscape is one of the key questions of our day."

The findings were published in a recent edition of the journal The Condor: Ornithological Applications.