More Debate Over Wind Turbine Impacts on Birds

Wind energy may be clean but it's not completely benign, at least according to some of the information from this article Peril in the Wind Industry: Turbines That Produce Clean Energy Also Kill Migrating Birds , Kimberly Edds, Washington Post (12/24/03) . According to Edd's report, scientists estimate that as many as 44,000 birds have been killed over the past twenty years at the Altamont Pass wind farms. Apparently, the area is within the migration route of many predatory birds, whose focus on ground prey causes them to fly into the fast-spinning blades. As a result of the experience at Altamont, wind power has had problems with environmental groups who have claimed that the wind industry is not doing enough to stop avian mortality.

But is Altamont an accurate baseline for measuring bird deaths in the wind industry. As the article continues:

Altamont was constructed in the early 1980s when little was known about the migration patterns of birds in nearby areas. Mistakes made at Altamont have been used to make improvements in new wind farms. No other wind farm in the United States comes close to the bird mortality rates at Altamont because of improved windmill design for newer farms. The industry says similar updates for Altamont would be too costly.

There's also confusion about what to do to mitigate the problem. The article describes that:

past attempts to reduce bird kills have included painting the tips of turbine blades to try to make them more visible to birds, installing screens around generators and putting devices to discourage perching on the towers. But those measures have failed to substantially lower the number of bird deaths. Among the measures now being discussed is letting the grass beneath the turbines grow taller and removing nearby rock to provide more cover for prey and discourage birds from flying in the area. "There is no universal agreement what the exact right thing to do is," Stengel said, noting that a few years ago the recommendation was to build rock piles near the turbines. Now the recommendation is the opposite.

The number of birds killed at Altamont seem high - but they don't tell everything. I'd be interested in knowing, for example, how bird kills at Altamont compare to the number of birds killed at airports or by skyscrapers. I'd also be interested in seeing the rate at which the numbers have declined over the years. Finally, what would be the substitute for wind power - a natural gas plant? More fossil fuel generation? Surely these sources also have adverse impacts - and not just on birds but on humans also.