Nest survival of Red-winged Blackbirds in agricultural areas developed for wind energy

• 534 nests were monitored at three paired turbine and control sites.
• We model daily nest survival for incubation and nestling stages.
• We found no difference in survival between control and turbine sites.
• Turbine proximity did not affect survival in the incubation stage.
• Survival was slightly higher closer to turbines in the nestling stage.

Wind energy development is a major priority in the United States, both economically and environmentally. However, there are growing concerns about the impacts to wildlife, including direct mortality and indirect effects such as displacement. Yet little knowledge has been gained regarding effects on reproduction. We monitored 534 Red-winged Blackbird (Agelaius pheoniceus) nests at three wind farms and paired control sites in Iowa during 2011 and 2012 to determine what effect, if any, wind turbine proximity had on the survival of nests. We modeled daily nest survival rates during the incubation and nestling stages in program MARK. In addition to proximity to turbine, we included other covariates which are known to effect nest survival including nest height, vegetation above nest, Robel pole vegetation density measures, age of nest, distance to woodlot, and Brown-headed Cowbird (Molothrus ater) parasitism. We found no differences in survival between our control and turbine sites at any site or year, and no effect of turbine proximity during the incubation stage. The best model for the nestling stage included a small effect of turbine proximity, with nest survival being slightly higher, though not significantly so, closer to turbines. Our results indicate that, for a generalist species breeding in an agricultural landscape, wind turbine proximity has negligible effects on reproductive success.