Bill Evans wants to make it clear he’s not against wind turbines.

“I’m not anti-wind. I’m a consultant who people call from both sides when there’s a concern about the impact on migrating birds,” he said.

Evans, 50, is an Ithaca-based ornithologist who has studied bird migration in North America for more than 25 years. He helped start the Cornell Laboratory of Ornithology’s research into avian night flight calls in the mid-1990s and in 1998 founded the non-profit group Old Bird Inc. The group promotes education and awareness of the nocturnal migration of birds and the use of technology to prevent bird collisions with tall, man-made structures.

Evans specializes in the use of acoustic monitoring equipment that records birds’ night-time flight calls. He is currently involved in a New York State Energy Research and Development Authority study at the Maple Ridge wind project. Located in Tug Hill in Lewis County, Maple Ridge is the state’s largest wind farm, with 199 turbines.

While at Maple Ridge, he has also researched and determined the feasibility of developing automatic collision monitors, which will be placed on the turbines and record every time there’s a bird collision.

Up to this point, researchers have seen no major bird kills at Maple Ridge, or any of the other wind farms in this state. However, New York’s new emphasis on green energy is expected to result in close to 3,000 new wind turbines being constructed across the state by 2013. Currently, there are more than 500.

Many birders and ornithologists, while enthusiastic about the development of energy alternatives to fossil fuels, are concerned about the lack of research concerning the environmental impact of wind turbines on wildlife. They stress the need for much forethought in the location of these structures. Evans talked this week about the issue:

What's the biggest concern when it comes to migrating birds and the location of wind turbines?

In this state, the biggest concern involves the pressure to place turbines in close proximity to the shores of Lakes Erie and Ontario. These shorelines have a good wind resource, but the closer wind turbines are to the lakeshore, the greater the bird mortality will likely be.

Many species fly around large bodies of water, and their flights tend to become concentrated in the vicinity of the lakeshore. Ideally, we wouldn't site wind projects within five miles of the Great Lakes.

Just so I'm clear, what kind of migrating birds are we talking about? More than 100 species, including most of our songbirds (warblers and sparrows, cuckoos, kinglets, larks, orioles, tanagers, thrushes, wrens, finches etc.), many of which make long migrations to and from Central and South America.

Also, many species of waterfowl (ducks and geese), other waterbirds such as herons, rails and sandpipers, and most of our raptors (hawks, eagles, falcons and owls).

What exactly are you monitoring with all your equipment. How accurate and thorough is your data? I monitor the calls birds give while they are flying in nocturnal migration. Most birds migrate at night, and many species give short call notes to keep in contact with one another and to work out their flight spacing to avoid collisions.

For example, my equipment can document how many vocal flocks of Canada geese passed over a location during the night. A location in a flyway may detect dozens of flocks. A location not on a flyway may not have any.

By putting out multiple acoustic monitoring stations in an array I can create a map of these varying nocturnal flight dynamics, which then can be of use for assessing potential wind farm impact.

What area would you not want to put a wind turbine? Besides the Great Lakes shoreline issue I mentioned, I certainly would not want to see wind projects near wildlife refuges or significant wetland areas. Also, certain box canyon geography in hilly or mountainous terrain can funnel migratory birds into dense concentrations.

Does their height affect the potential danger to migrating birds? Yes, the taller they are, the more impact on birds they will likely have.

Are birds the only things that potentially are threatened by wind turbines? No, some species of bats are taking quite a hit. They appear to be attracted to wind turbines and some are killed in collisions with the rotor blades. Others succumb to what is termed "barotrauma." Bats have very fragile lungs and when a bat flies in close proximity to a wind turbine's rotor blades their lungs can collapse.

Others talk about the need for thorough environmental impact studies before approving the placement of a wind turbine. How long time-wise would you recommend such a study be and why? This really depends on the location of the project. Some wind project sites may not need much pre-construction environmental study; others may need several years. It often depends on how many (and to what extent) threatened or endangered species are involved.

The state Department of Environmental Conservation has some of the best guidelines in the country for evaluating environmental impact of wind projects — but there is still a lot to be learned in how we can reduce bird and bat collision fatalities.

What's the one thing people would be surprised to learn about the night migration of birds? That birds have GPS. As they become an adult, they can navigate with incredible precision night or day. They do this using the sun, stars, earth's magnetic field, and in some cases an inborn genetic program. Some species are genetically programmed to migrate thousands of miles in a certain direction.



More on the issue

Ornithologist Bill Evans is scheduled to speak at 7 p.m. Wednesday at the Onondaga Audubon Society's monthly meeting in Room 319 Marshall Hall on the SUNY ESF campus in Syracuse. Evans, executive director of Old Bird Inc. will speak on night bird migration and conservation implications and acoustic monitoring in assessing impacts of industrial wind turbines and cell towers. For information, call 771-6902. Check out the Old Bird Web site at www.oldbird.org

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