| Raptor Electrocution on Power
Lines: Problem Assessment, Mitigation, and Monitoring
Graduate Student: Bob Lehman
Project Start Date: 07/05/00
Expected Completion Date: 12/31/03
Funding Agency: U.S. Fish and Wildlife Service (RWO 61)
Introduction: This is a monitoring study designed to assess raptor electrocution problems in 2 study areas in Colorado, Utah and Idaho. Our goals are to increase our understanding of the dynamics of raptor electrocution, to show how well retrofitting practices currently in use by the electric industry are working, and ultimately to provide the industry with a model of problem assessment, mitigation, and monitoring based on sound sampling procedures.
Objectives: Specific objectives are: 1) estimate and contrast electrocution mortality among selected pole types and habitat categories; 2) evaluate biasing factors that may influence estimates of electrocution mortality; 3) determine if raptors show preferences for particular poles; 4) evaluate the effectiveness of specific retrofitting procedures; and 5) contrast incidental vs. systematic sampling to assess current approaches to monitoring. We will also assess cause of death of a sample of birds brought to the National Eagle Repository near Denver to assess accuracy of mortality reporting there, and we will develop a mortality data base for use by Repository personnel.
Progress: During the first half of 2003, we monitored over 250 km of power lines and nearly 1000 individual poles on quarterly schedules. We also conducted carcass removal trials and raptor perch surveys in the Rangely Oil Field, and conducted over 50 necropsies of dead birds. Based on the results of previous surveys indicating that sample sizes from random sampling were small, and that a large proportion of mortality on the Moon Lake system occurs in the Rangely Oil Field, we discontinued quarterly power line and pole surveys outside the oil field and from July through December focused our effort there. In December 2003, we received a grant from the California Energy Commission to extend the project. The grant is being administered through the U.S. Geological Survey. As a result data In March 2003 we were notified that we will receive an additional grant for the project, in the amount of $60,000 from the California Energy Commission.
Results/Products: During fall 2003, we prepared a final report for the project. That report is available from the cooperative research unit. The work will also form a portion of Bob Lehman's Ph.D. dissertation. Ultimately, the research will be presented at professional meetings and published in a peer-reviewed journal. A preliminary paper has already been published:
Lehman, R. N. 2001. Raptor electrocution on power lines: current issues
and outlook. The Wildlife Society Bulletin 29:804-813.