Date of Award:
Master of Science (MS)
Terry A. Messmer
Terry A. Messmer
John W. Connelly
R. Douglas Ramsey
The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is a species of conservation concern in Utah and across their range throughout the western US and southern Canada. Sage-grouse decline is primarily a result of declines in sagebrush habitat on which sage-grouse depend for winter, summer, nesting, and brood habitat. Detailed site-specific knowledge of sage-grouse ecology and distribution in needed to effectively conserve the species. To expand knowledge of local populations within the West Box Elder Sage Grouse Management Area (SGMA) in NW Utah and gain insights into the effectiveness of vegetation treatments intended to benefit sage-grouse, I radio marked and tracked 123 (68 female, 55 male) sage-grouse and conducted pellet surveys on 19 conifer reduction projects.
I generated seasonal habitat models to predict seasonal habitat use within the West Box Elder SGMA using vegetation and topographical data coupled with radio telemetry locations to aid in prioritization and optimal placement of sage-grouse habitat improvement projects. Output maps were generated from models that indicated probability of sage-grouse use during brood, nesting, early summer non-breeding, late summer non-breeding, winter and lekking (early spring) periods. In addition, a vegetation disturbance dataset was generated from satellite imagery and available maps for the period from 1985 to 2013. However, disturbance at the above temporal and spatial scale was not an influential predictor of sage-grouse distribution.
Conifer reduction projects are thought to be a cost effective method of restoring habitat to a state useable by sage-grouse in areas that have been invaded by pinyon pine (Pinus spp.) and juniper (Juniperus spp.). However, little information specific to sagegrouse on the effectiveness of conifer reduction is available. I evaluated sage-grouse use of conifer reduction treatments using radio telemetry and fecal pellet surveys within conifer reduction projects. Sage-grouse use was detected in 12 of 19 treatments surveyed. Use was positively associated with sage-grouse presence in adjacent habitat, mesic areas surrounding treatments, and higher shrub cover within treatments. Higher conifer density surrounding a treatment was associated with less use of conifer reduction projects.
Biologists have expressed concerns that differences in individual bird behavior or effects of capture could affect capture probability and bias reported vital rates. I monitored 204 radio-marked sage-grouse within the West Box Elder and Rich-Morgan-Summit SGMAs in Utah between January 2012 and March 2013 to evaluate effects of individual behavior and capture stress on survival and reproductive success. Sage-grouse that flushed one or more times prior to capture had higher brood and annual survival rates than those that did not. Sage-grouse that were handled longer or experienced more capture trauma had decreased survival probabilities. My results suggest researchers need to consider the effects of capture and handling when reporting sage-grouse vital rates obtained through radio-marking
Cook, Avery, "Greater Sage-Grouse Seasonal Habitat Models, Response to Juniper Reduction and Effects of Capture Behavior on Vital Rates, in Northwest Utah" (2015). All Graduate Theses and Dissertations, Spring 1920 to Summer 2023. 4369.
Copyright for this work is retained by the student. If you have any questions regarding the inclusion of this work in the Digital Commons, please email us at .