A state wildlife biologist says the Whistling Ridge Wind Project, proposed for a timbered ridge in eastern Skamania County, could cause high wildlife mortality, especially for bats and raptors.

Surveys of the 1,152-acre site, including those done for the applicant, Bingen-based SDS Lumber Co., show the area is heavily used by bats, raptors and other birds, biologist Michael Ritter said in formal comments to the state agency that will decide whether to approve the project.

Use of the area by bats and raptors is higher than in most other wind resource areas evaluated in the western United States, said Ritter, a wind mitigation biologist based in Pasco.

In its application to the Energy Facility Site Evaluation Council, SDS reported that overall use of the project site by raptors was "very low," though the company's wildlife consultant predicted there would be some collisions between turbine blades and small birds and bats.

The barred owl, which competes with the threatened northern spotted owl for prey and habitat, also has been recorded frequently in surveys of the site, Ritter said. Although no spotted owls have been recorded on SDS land, the site of the proposed wind farm is immediately south of one of the state's few spotted owl special management areas on state land.

SDS has approached the state about the possibility of a future expansion of the project onto that land, which is managed by the Department of Natural Resources.

The Washington Department of Fish and Wildlife supports additional surveys of the site, especially for bats, northern goshawks and owls, Ritter said - even though the results of those surveys might be of limited use.

"It is unlikely that the additional data ... will alleviate the concerns we have with potential impacts to birds and bats with this wind energy project," he wrote.

Comparisons with existing wind projects in Washington are all but meaningless, Ritter said. That's because the Whistling Ridge project would be the first in a westside conifer forest in the Pacific Northwest. Every wind project built in the region to date is on arid, open shrub-steppe or agricultural land east of the Cascades.

"All of our collective knowledge in Washington and Oregon comes from shrub-steppe," Ritter said in an interview. "In this project, we see pileated woodpeckers and a good cross-section of birds."

No data exist to indicate how birds and bats that use westside commercial forests would fare if they came in contact with a string of 50 wind turbines, each extending 426 feet from base to blade, as proposed for the Whistling Ridge project.

What is clear is that high numbers of raptors, bats and birds have been recorded at the site, Ritter said.

In particular, the survey data on bats is "extremely interesting and alarming," Ritter said. One survey found an average of 138 bat passes per night at each of three locations within the project site. That's a number more than three times as high as at any other wind project site in the nation, he said.

Bats die in wind turbines not just from colliding with the blades but also from an effect known as "barotrauma," which creates internal hemorrhaging when the bats encounter changes in barometric air pressure around the blades, Ritter said.

"The air pressure changes around those big blades and the bats drop out of the air," he said.

Given the uncertainties surrounding the site, Ritter wrote, "Our approach to this project at this point in time is to proceed cautiously, carefully consider, protect and conserve the natural resources of the site and adjacent lands, and slow down the incentivized green energy freight train that is barreling through the state of Washington."