Impacts of oil and gas development on sharp-tailed grouse on the Little Missouri National Grasslands, North Dakota

Oil and gas development and their attendant structures (i.e., power lines, roads and collection stations) have increased across western North America since the 1930s, resulting in direct habitat loss, and fragmentation of remaining suitable habitat (Braun et al. 2002). Both short- and long-term habitat losses may be associated with energy development (Lyon and Anderson 2003). Although numerous studies have shown oil and gas development has impacted many avian species, particularly sage grouse (Centrocercus urophasianus) (Braun et al. 2002), little is known about the effects of oil and gas development on sharp-tailed grouse (Tympanuchus phasianellus). This 2-year study was initiated to determine the impacts of oil and gas development on plains sharp-tailed grouse (T. p. jamesi) on the Little Missouri National Grasslands in North Dakota. The study site was divided into two areas based on the presence of oil and gas development; one area that is developed and one area that is free from development. During 2006 and 2007, 90 hens were radio-collared and their nest locations, hatching success, hen and brood survivorship, and daily locations were used to estimate the impacts of oil and gas development on sharp-tailed grouse. Reproductive success did not vary between sites other than brood survival in 2006 (Chi-square=10.16, df=1, p=0.001). Available habitat across the entire study site appeared to be the driving force for where grouse nested and spent the brood-rearing period. Micro-habitats within each study site differed very little indicating that habitats used had little or no impact on survival rates. Few differences were found between the two study sites, mostly between habitat use and availability. Available grass canopy cover (F=7.37; df=1,50; p=0.009) during the brood-rearing period in 2007 was higher in the developed area. Much of the developed study site consisted of large, deep river breaks, or had been converted to cropland or hayland. Marked birds did not use the river breaks and converted lands were used in moderation, primarily after nesting season was completed. Results indicated that daily locations and nest site selection were chosen based upon availability of habitat within the developed area, and sharp-tailed grouse did not appear to choose for or avoid the areas under development. I recommend that supporting agencies focus their management actions on the remaining leks within the oil field, particularly on the surrounding habitats where the current oil and gas development is expanding into. The leks are the focal point for annual reproduction and movements of the remaining grouse and if these habitats are severely altered or lost, the grouse population within the oil field can experience a decrease in numbers.