For the Birds Radio Program: Tower Update

Original Air Date: Dec. 28, 1987

Several prominent ornithologists have weighed in on U.S.West’s proposed tower on Moose Mountain, in the direct path of bird migration.

Audio missing


(Recording of a Bald Eagle)

Ever since I spoke out against U S West for its plan to build a cellular phone tower on Moose Mountain, people have been asking me how birds can possibly be stupid enough to fly into guy lines. After all, everyone knows that birds have exceptionally acute vision.

Maybe it has something to do with the artistic rule that there are no straight lines in nature, but most birds simply do not see wires strung out in their airspace. A study published by the U.S. Fish and Wildlife Service this year indicated that fully 68% of birds flying in the vicinity of power lines strung out across the Great Plains didn’t respond to them at all. And the ones that did usually flared up, often hitting the wire above the one they were avoiding. Dr. Pat Redig, the director of the Raptor Research and Rehabilitation Program in St. Paul, wrote to me that he has treated at least 5 Bald Eagles, 5 Peregrine Falcons, 1 gyrfalcon, and several other species which had definitely collided with suspended wires. He said, “The injuries sustained by the birds include severe fractures and occasionally outright amputation of the wing by the wire, indicating that they are struck at high speed.” Dr. Redig continued, “I have personally witnessed raptors flying into power lines…and I know that they not only don’t see them, but they are not looking for them either. In other words, there is nothing in the learning mechanisms of these birds that gives them any reason to [be] concerned about objects suspended in an otherwise open sky.”

Other ornithologists share Dr. Redig’s concern about a tower on Moose Mountain. Bob Janssen, editor of Minnesota’s ornithological journal, The Loon, and author of Birds in Minnesota, wrote to me from Minnetonka, “There couldn’t be a worse place in the state to install a tower of this magnitude. Moose Mountain is directly in line with the largest migration route in the state of Minnesota, and probably one of the largest anywhere in the United States. To place a 290’ tower in this area with its associated holding cables would be a ‘bird killer’ of great magnitude.”

Dr. Harrison Tordoff, curator of the Bell Museum of Natural History, professor of Ecology and Behavioral Biology at the University of Minnesota, and past president of the American Ornithologists’ Union, wrote from Minneapolis, “…the lethal attraction of towers at night comes from the lights on the towers which are intended to warn aircraft…The prescription for disaster is a low ceiling, fog, and often drizzle on a night when birds are migrating in great numbers. The migrants, confused by the poor visibility, are attracted to the tower lights, as moths to a flame, where they collide with one another, the tower, or its guy wires…It is not mere speculation to predict that a tower on Moose Mountain would cause substantial mortality to migrating birds. Local circumstances would make such mortality a virtual certainty.”

I have letters and statements from several other prominent bird experts–all strongly supporting my opposition to U S West’s proposed tower. I can’t think of any other issue that has ever rallied so many ornithologists to voluntarily write statements like this. As Bob Janssen wrote, “I doubt if U S West would want to be known as the major bird killer in the state of Minnesota. I urge them to find an alternative site.”

(Recording of a Bald Eagle) This is Laura Erickson, and this program has been “For the Birds.”