Calpine Corporation (Calpine) is assessing the feasibility of developing the Big Blue River Wind Project (BBRWP) located in Henry County, Indiana. Calpine asked Western Ecosystems Technology, Inc. (WEST) to conduct fixed-point count avian use surveys to estimate potential impacts of the BBRWP to eagles and other birds consistent with the US Fish and Wildlife Service (USFWS) Eagle Conservation Plan Guidance and USFWS Land-Based Wind Energy Guidelines.
Ten-minute small bird and 60-minute large bird fixed-point count surveys were conducted at 43 points in the BBRWP from December 3, 2015 through June 30, 2016, and at 46 points from July 1, 2016 through November 29, 2016 due to a small change in the project boundary. Seven bald eagles were observed throughout all surveys. Five occurred during large bird use surveys, one during small bird surveys, and one incidental. Overall eagle use within the BBRWP was low, with only three minutes recorded for eagles flying within the rotor swept height. The BBRWP lacks suitable bald eagle nesting and hunting habitat throughout the majority development area. Summit Lake State Park, located outside the BBWRP, and Province Ponds Fish and Wildlife Area, a small lake and wetland located in the northeast portion of the BBWRP, boundary provide more suitable habitat for nesting and foraging.
Eighty-four unique bird species were observed during all fixed-point count avian use surveys in the BBRWP. European starling, red-winged blackbird, and horned lark were the most abundant bird species observed during small bird fixed-point count surveys at BBRWP. Canada geese and turkey vultures were the most abundant birds observed during the large bird fixed-point count surveys. Turkey vulture and red-tailed hawk were the most frequently observed large bird species in the BBRWP.
No species protected by the federal Endangered Species Act were observed during the surveys. Two state-endangered species were observed: northern harrier and osprey. In addition, five species of concern were observed: bald eagle, common nighthawk, redshouldered hawk, sandhill crane, and sharp-shinned hawk. The potential for collision with turbines for these species is expected to be low due to their low abundance and the relatively low fatality numbers documented at other wind energy facilities with publicly available data.