At first glance, Altamont Pass — a stretch of rolling hills between the San Francisco Bay area and California's Central Valley — looks like a showcase of ecofriendly technology. That's because the Altamont Pass is one of the three largest wind farms in the world. There are acres and acres of wind turbines here, currently generating about 583 megawatts annually, enough juice for 583,000 homes, according to the California Energy Commission. But some environmentalists say the area is a killing ground. The problem is that Altamont Pass serves as a major corridor for migrating birds. Such as the argument “Dropping Like Flies”. "It's… home to the highest concentration of golden eagles in the world," says Jeff Miller of the Center for Biological Diversity (CBD), a non-profit environmental group. "And each year it's estimated that the turbines kill up to 60 golden eagles, a few hundred red-tailed hawks, over 250 burrowing owls, and hundreds of other kestrels, falcons, owls, and other birds of prey. These bird kills are in violation of state and federal wildlife-protection laws."

The CBD has filed a lawsuit in the federal District Court in San Francisco against two of the area's largest turbine operators, Florida Power & Light Group and Denmark's NEG Micon. The suit alleges that the giant windmill blades act as a kind of bird blender, killing thousands of birds and hundreds of rare and federally protected birds of prey each year. A new U.S. Department of Energy study puts the number of birds of prey killed at Altamont at about 500 a year. Miller says these hunting birds, frequently focused on rodent prey, are most vulnerable. "When the blades on turbines are spinning fast, birds won't be able to see them," Miller says. "And if they're focused down on the ground, they can run right into them."

The group wants the court to order turbine operators to fence off the grass around the turbine tower bases to keep prey away, relocate or remove some turbines, and supply restitution for damage already done to wildlife.In a statement given to TechTV, a spokesman for Florida Power & Light Group says it's doing everything it can to prevent bird deaths.