PARENT SESSION
Symposium 5: Fighting the Odds: The Challenge to Save the Sagebrush Biome.
Organized by: CS Duke, ST Knick, and DA Pyke
Tuesday, August 3, 8:00 AM to 11:30 AM, Oregon Ballroom 203.

Impact of energy development on sagebrush ecosystems.

Finn, Sean^*,1, Knick, Steven¹, Rinkes, E. Thomas², ¹ U.S. Geological Survey, Biological Resources Division, Boise, ID, USA² Bureau of Land Management, Lander, WY, USA

ABSTRACT- A recent analysis under the Energy Policy and Conservation Act (re-authorized in 2000) identified 5 geologic basins that contained the primary onshore oil and gas reserves in the western U.S. The vast majority of >122,000 leases authorized since 1929 by the U.S. Bureau of Land Management for development of oil and gas resources have been granted on federal lands, primarily in the Wyoming Basins and the eastern Great Basin. Oil and gas development has direct and indirect consequences for sagebrush ecosystems. The direct loss of habitats to wells, pipelines, and road networks was a minimum of 0.5 million ha. Oil and gas development potentially exerts an influence on 25% of all existing sagebrush landscapes by increased predation, spread of exotic plants, and noise disturbance. Landscape changes and subsequent impacts on plant and wildlife populations are not consistent across the sagebrush biome because of spatial and temporal differences in vegetation patterns, the extent and duration of well-based disturbance, and the inherent resiliency of the ecosystems to respond to disturbance. For example, well pads for coal-bed natural gas averaged 0.1 ha on flat ground in the Powder River Basin in northeastern Wyoming whereas pads may exceed 7 ha in gas fields in western Wyoming. Because sagebrush cover in the Powder River is interspersed with native grasslands, the construction of well pads, even though smaller, further fragments and reduces sagebrush cover. Temporally, the impact of energy development varies as oil and gas fields decline in production and new sources and technologies are discovered. The National Petroleum Council projected that demand for oil was expected to remain constant but natural gas demand could increase by 32% by 2010. The cumulative disturbance associated with oil and gas production and transport, such as roads, powerlines, and processing facilities may be more significant in disrupting ecosystem processes than any single source.

Key words: oil, disturbance, sagebrush, natural gas