Site loading image


Post Construction Avian and Bat Mortality Surveys

In late 2016, Enel Green Power North America began operation of the Drift Sand and Chisholm View II wind projects in Oklahoma. Prior to construction, Enel worked closely with the Oklahoma Dept. of Wildlife Conservation and the U.S. Fish and Wildlife Service to develop and implement Bird and Bat Conservation Strategies (BBCS) that assess the impacts to avian and bat species and outline requirements for post-construction surveys.


TRC biologists completed comprehensive data collection and analysis at both sites to support Enel’s compliance with the BBCS. TRC adjusted study designs at Enel’s request to accommodate requirements beyond those described in the BBCS and documented the species and number of individual fatalities during spring, summer and fall 2017, and estimated the level of fatalities based on standardized searches, carcass persistence and searcher efficiency trials. In accordance with the BBCS, TRC also provided on-site training for operation and maintenance staff on threatened and endangered species identification and a Wildlife Incident Reporting System protocol.

Drift Sand is a 54-turbine, 108 MW project in Grady County, Oklahoma. It includes 20 miles of private access roads, 4 miles of overhead transmission lines and 28 miles of underground collection lines. The BBCS required at least 30 percent of the turbines be surveyed within an 80m square search area. TRC conducted eight rounds of surveys in the spring, four rounds in the summer and eight rounds in the fall.

Chisholm View II is a 27-turbine, 64 MW project in Garfield County, Oklahoma. It includes 5 miles of private access roads and 17 miles of underground collection lines. The BBCS required that 100 percent of the turbines be surveyed within an 80m square area. TRC conducted five rounds of surveys in the spring, three rounds in the summer, 10 rounds in the fall and 2 additional rounds in late fall.

Both projects were successfully completed, with mid-year reports, trainings and final reports delivered to the client’s satisfaction.

Enel Green Power

Project Location

Looking for effective solutions to your problems?

Turn to the experts at TRC.

By clicking "Accept", you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. Read our Privacy Policy.