WORLD WIND ENERGY NET

PORTLAND -- The rapid expansion of wind-energy farms in the Columbia River Gorge's shrub steppes could put hawks, eagles and other raptors on a collision course with fields of giant turbines and their 45-metre (150-foot) blades.

By year's end, more than 1,500 turbines will be churning out electricity in the gorge. Most of the projects have been erected in wheat fields, cultivated land from which rodents that raptors hunt were driven away.

But as wind energy developers move into wilder areas along the gorge's ridge lines, the potential for conflict rises. If bird studies confirm the fears of Oregon and Washington state wildlife biologists, the green-minded Northwest might be forced to weigh its pursuit of pollution-free energy against the toll on raptors and other birds.

The numbers sound small: Nationwide, collisions kill about 2.3 birds of all varieties per turbine per year, studies show. In the Northwest, it's about 1.9 birds per turbine. That could mean more than 3,000 bird deaths a year in the gorge.
But birders say those numbers are meaningless because the totals make no distinction between abundant and rare species. Golden eagles and ferruginous hawks -- a threatened species in Washington -- already are few in number, said Michael Denny of the Blue Mountain Audubon Society. Raptors generally fly 90 to 120 metres (300 to 400 feet) above the ground -- about the height of most wind turbines.