This is an excerpt from the Fourth Quarter 2012 edition of the Wind Program R&D Newsletter.
A DOE Success Story
A team of researchers led by Dr. Todd Katzner at the West Virginia University (WVU) is using a global positioning system (GPS) similar to that found in a smart phone to track movements of golden eagles and gain a deeper understanding of the risks they face from wind energy development as they migrate through the Appalachian Mountains. Funded by a 2-year U.S. Department of Energy Wind Program grant, the team's findings will characterize potential risks and suggest risk management strategies to protect migrating golden eagles and other soaring birds of prey.
Risks posed by wind energy development to migratory species, such as golden eagles, have been of great concern since it was discovered that some eagles were killed at the Altamont Pass Wind Resource Area in California. This issue has received even greater attention since the U.S. Fish & Wildlife service published its Land-Based Wind Energy Guidelines and Eagle Conservation Plan Guidance in 2011. The study conducted by the WVU team is providing telemetry data of unprecedented temporal and spatial resolution to help the wind industry and land managers address these guidelines.
The research team collected the data for the study by outfitting eagles with a small, lightweight device they designed that uses a GPS to collect high-resolution data on eagle movements. The data are transmitted back to the team over the mobile phone (GSM) network. Because the data were collected at 30-second intervals between GPS fixes, the team had the ability to interpret and model the eagle flight data at a resolution never before achieved.
Previous studies have used radar or gliders to track birds that soar in high-altitude airstreams well above the height of most turbines. But when migrating raptors travel closer to the ground, they are at greater risk from wind turbines.
The data collected by the WVU team were combined with publicly available habitat and meteorological data sets to provide new insight on how eagles conserve energy by utilizing the wind resources that occur at lower altitudes to glide over steep slopes and cliffs. This is important for conservation management because flight altitude is a key component of the risk birds face from modern horizontal-axis wind turbines that are typically 50 to 150 meters above the ground. The knowledge gained from this study will help wind developers improve siting and micrositing and determine if mitigation actions are required.
"Our team believes that engaging with industry will reduce risk to birds from turbine development and we are thrilled to have the opportunity to work in this way." Katzner said. "The ultimate goal of our work is for wind energy development to be as 'bird friendly' as possible."