Oil and Gas Impacts on Wyoming's Sagegrouse: Summarizing the Past and Predicting the Foreseeable Future
Historical impacts from oil and gas development to greater sage-grouse (Centrocercus urophasianus) habitat are well-documented in some areas of Wyoming, in particular within natural gas development fields, such as the Powder River Basin and Jonah-Pinedale. The drilling techniques and pad densities in these fields have been extrapolated to estimate future oil and gas impacts in the U. S. Fish and Wildlife Service (2010) warrantedbut-precluded listing determination for the sage-grouse under the
... -grouse under the Endangered Species Act. Further, assumptions regarding the scale of oil and gas development are incorporated within various resource management plan amendments by the Bureau of Land Management (BLM) throughout the range of the sage-grouse. We evaluated the status of Wyoming sage-grouse leks by quantifying the scale of oil and gas impacts across the state of Wyoming and the extent that sage-grouse persistence is impacted by oil and gas development using the impact analysis lens of well-pad density within a 3.2-km radius of a lek (Doherty et al. 2010) . The analysis provides that 75% (1,770 out of 2,356 leks analyzed) of identified leks (active and inactive) have <12 wells within a 3.2-km radius of a lek and are expected to have indiscernible impacts from oil and gas development in terms of lek attendance (Doherty et al. 2010). As to future development of oil and gas in Wyoming, 64% of Wyoming leks (1,508 leks) are protected from oil and gas development densities of >12 wells per 32.2-km 2 , due to prescriptive density and disturbance restrictions within the Wyoming Core Area Policy. The Wyoming Core Area Policy protects priority sage-grouse habitats by limiting surface disturbance to an average of 5%. Specific to oil and gas development, a prescriptive density standard allows an average of 1 well pad per square mile. Thus, the combination of core area protections with the technological shift to directional and horizontal drilling that is being deployed in both existing and new fields to recover hydrocarbons (i.e., technologies that dramatically reduce the fragmentation and disturbance profiles of oil and gas development), suggests that threat projections in the U.S. Fish and Wildlife Service (2010) listing decision on sage-grouse due to future oil and gas development have been overstated.