Bat Fatality Monitoring Report for the Pigeon Creek Wind Turbine 

This research effort was conducted as part of the Habitat Conservation Plan for Adams Electric Cooperative for the Pigeon Creek Wind Turbine, Adams County, Illinois. A contractual agreement was made with John Wood Community College, Quincy, Illinois, and research was conducted by Sharon DeWitt, a faculty member, and Cindy Spohr, a student intern in the Natural Sciences Department. Monitoring of the wind facility was conducted during the summers of 2010 and 2011 and occurred from mid June through September 30th both years. Our primary objective was to determine the impact of the turbine on bat populations, with a specific focus on two endangered species of concern: Myotis sodalis (Indiana bat) and Myotis grisescens (Gray bat). We were also interested in assessing if the turbine was above, at, or below the national average for bat fatalities.

The monitoring site consists of a 55m² area surrounding the turbine base which has been cleared of vegetation and the ground surface covered with gravel. A six foot chain link fence enclosure separates the site from the surrounding agricultural fields. Monitoring was done twice weekly, June 14 to September 30, 2010, and June 17 through September 30, 2011. Originally, the plan proposed beginning the process on May 15 of each year to include spring bat migration. Unfortunately, the turbine was not operational, May 15–mid June either year, thus data for spring migration of bats was entirely missed during both monitoring periods. [emphasis added] …

A total of 23 bats were collected during the fatality searches in 2010. Consistent with other wind turbine studies, the majority of the bat fatalities, 52%, belonged to migratory tree roosting species; eastern red bat (Lasiurus borealis) and hoary bat (Lasiurus cinereus). Of the remaining fatalities, 37% consisted of little brown bat (Myotis lucifugus) and big brown bat (Eptesicus fuscus). A total of 4 bats were collected during 2011, with only one migratory bat, silver-haired bat (Lasionycteris noctivagens). The rest of the bat carcasses belonged to three resident species, eastern pipistrelle (Perimyotis subf!avus), evening bat (Nycticeius humeralis), and little brown (Myotis lucifugus) bats. No species of concern were found during either monitoring period.

The Jain estimate was used to correct for carcasses missed by the searcher and removed by scavengers. Performance of the calculation returned an estimate of 30 fatalities for 2010 and 18 fatalities for 2011. Both estimates are above the reported national average of 3.4 bats per turbine per years. …

Download original document: “AEC Pigeon Creek Turbine Bat Mortality Study 2010-11”