In the topical and informative article about wind impact on sage grouse, I do take exception to the comment "At this point, no one really knows how turbines affect grouse"  (HCN, 6/22 & 7/6/09). While it's true that wind farms pose a negligible direct mortality threat, sage grouse do avoid vertical structures and are negatively impacted by associated fragmentation. Grouse need between four to six kilometers of healthy sage as a buffer around leks to migrate between winter and summer range. Roads, traffic, dust overlay and power lines all contribute to the steady decline in grouse and other sage obligate populations. Green energy is great, but fragmentation of core habitat is driving the grouse to a listing on the endangered species list.

Dave Showalter
Arvada, Colorado