A lawsuit contending the whirling blades on the hundreds of windmills in the Altamont Pass area are killing birds has been rejected by the First District Court of Appeal.

"Permitting the action to proceed as presented would require the court to make complex and delicate balancing judgments without the benefit of the expertise of the agencies responsible for protecting the trust resources and would threaten redundancy at best and inconsistency at worst," the appellate court decision says.

The Center for Biological Diversity Inc., a nonprofit corporation with over 12,000 members, more than 4,400 of whom reside in California, had sued the windmill operators, FPL Group Inc.; FPL Energy LLC; ESI Bay Area GP Inc.; ESI Bay Area Inc.; Altamont Power LLC; Green Ridge Power LLC; GREP Bay Area Holdings LLC; AES SeaWest, Inc. (formerly SeaWest WindPower Inc.) and enXco Inc.

The lawsuit contends the wind turbine generators have killed and injured tens of thousands of birds including eagles, hawks, falcons, owls, and other raptors, as well as other birds.

The appeals court says the responsible public agencies have not ignored this concern and are attempting to mitigate the harm to birdlife by imposing appropriate conditions and restrictions on the operation of the turbines.

"We are in no position at this time and on this record to pass judgment on the sufficiency of those efforts or to express any opinion as to whether the public trust over these natural resources is being adequately enforced. What we do say is that any challenge to the adequacy of the measures being taken must be addressed in an appropriate manner to the agencies that are responsible for regulating those activities. The courts are available to review the responses of those agencies, but they are not available to supersede their role in the regulatory process," the ruling says.