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Comments on Proposals for Windpower Facilities on Allegheny Ridges Chandler S. Robbins. Sc.D. 7902 Brooklyn Bridge Road Laurel, Maryland Phone 301-497-5641 I am concerned because a 44-page report written for Clipper Windpower, Inc. by my friend Paul Kerlinger appears to grossly misrepresent the threat to migratory birds by the windpower Project. Paul is a respected New Jersey birder who has done research on hawk flights, etc. on the New Jersey shore, but he is totally unfamiliar with bird migration in western Maryland and he failed to contact people who are knowledgeable about that migration. He also failed to examine the 55 years of bird migration material published in Maryland Birdlife, of which I am editor. He claimed that the ridge tops were not important to migrating birds, even though in Appendix 3 he quoted Ed Thompson as saying "lots of birds use them" and he cited Bob Ringler as saying the ridge tops are "primary routes for migrating songbirds."
We have known for 50 years (Robbins. Maryland Birdlife 6:1-11, 1950) that migrating hawks use essentially all the ridges in western Maryland during their spring and fall migrations. Nearly all the hawks and eagles that nest in the northeastern U.S. and the eastern provinces of Canada migrate through Maryland. Tens of thousands of them take advantage of the rising air currents over the ridges every year. One of the rarest of these is the Golden Eagle. Over the years, the late Jim Paulus counted a very impressive 500 Golden Eagles as well as tens of thousands of other raptors migrating along the top of Town Hill ridge.
It is common knowledge that thrushes, which are notoriously vocal in flight, fly low along the ridges in their nocturnal migration. Paul acknowledged in Appendix 3 that Bob Ringler had mentioned this, yet in the main report Paul claimed that the birds only flew high and would not be low enough to hit the blades. More than 50 years ago, Orville Crowder and I set up a spotting scope beside old route US 40 at the summit of Town Hill and watched the silhouettes of migrating birds crossing the full moon. These migrants were flying just a few hundred feet above the ground and were easily audible from our position. Paul's statement that "night migrants are not known to follow ridges at night" is dead wrong and is irresponsible and dangerous when used to imply that ridgetop wind generators are no hazard to migrating birds.
Migrants are well known to follow "leading lines" such as shorelines, rivers, and ridges that are oriented in the direction they are heading. Migrants gain lift from the updrafts along even minor ridges, such as along the Fall Line where my house in Laurel is located. In a continent-wide study of nocturnal migration in 1953 (Lowery and Newman, pp. 238-263 in Recent Studies in Avian Biology by Albert Wolfson, ed., Univ. Ill. Press. 1955) involving observations at 325 localities, my Fall Line tally of birds silhouetted against the moon on the night of September 22-23, 1953, was the highest on the continent; when extrapolated to the standard measurement of birds crossing a line one mile long (and corrected for the angle of the moon), it was determined that 230.000 migrants passed over my house that one night.\
Paul acknowledged that birds do follow the Allegheny Front based on George Hall's fall migration banding station. I looked at Dr. Hall’s fall banding summaries for the last five years for which they have been published in North American Bird Bander (1996-2000) and compared his catch per unit effort with mine in Laurel for the same five years. He caught an average of 67 birds per 100 net-hours compared to 9 at my station. By this ratio, 1.7 million birds could migrate along the Allegheny Front in a single night, and using William Evans' acoustic measurements from the Appalachians in upstate New York (Applications of Acoustic Bird Monitoring for the Wind Power Industry, see www.nationalwind.org/pubs/avian98/21•Evans-Acoustics.pdf), one quarter of these (more than 400,000 birds) would be flying less than 400 feet above the ridgetop.
Migration along the ridges certainly is not inconsequential as claimed by Paul Kerlinger. Millions of birds from the northern half of the North American continent regularly funnel into the Appalachian ridges; see the Canadian Atlas of Bird Banding by D. Brewer et al. (Special Publication, Canadian Wildlife Service. 2000) to view documented records of birds from all across Canada converging on the Appalachian ridges.
Paul did correctly cite material from Christmas Counts, Breeding Bird Survey. and the MD/DC Atlas, to show that there were no endangered species nesting or wintering at the sites. He did not mention, however, that the entire population of the endangered Kirtland's warbler has to fly over the central Appalachians twice a year between their Michigan breeding ground and their winter home in the Bahamas.
He cited many references to lack of, or small number of bird casualties, at similar installations elsewhere, but in no case did he provide supporting evidence of protocol and time spent (if any) searching for dead birds.
In view of the enormity of the potential threat to the North American migratory bird population, it is my strong recommendation that no construction should begin on this project in Maryland until the impact on birds at a similar unit that is nearing completion in nearby west Virginia is thoroughly evaluated. Qualifications of author: Birds of Maryland and DC, 1958 (coauthor with R. E. Stewart) Birds of North America. 1966 (senior author) Trustee, Cornell Laboratory of Ornithology, 1982-87 Trustee, Hawk Mountain Sanctuary Association, 1987-99 Trustee, Hawk Migration Association of North America, 1988-93 Research Wildlife Biologist with U.S. Fish and Wildlife Service, 48 years Past President, Maryland Ornithological Society Editor, Maryland Birdlife, 50+ years Technical Editor, Audubon Field Notes/American Birds. 1952-89 Senior Editor, Atlas of the Breeding Birds of Maryland and DC, 1996 Fellow, American Ornithologists' Union Council Member, Association of Field Ornithologists, 1999-2003
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