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Ecological Investigations of Chukars in Western UtahLarsen, Randy T. 11 July 2006 (has links) (PDF)
This thesis presents three separate manuscripts in chapter format dealing with the ecology of Chukars (Alectoris chukar) in western North America. All three manuscripts have been formatted for publication in professional journals. Chapter one confirms discovery of ingested lead pellets in Chukars across a broad region of western Utah including all four western counties sampled. Prevalence rates were 1.9% (n=105) for crops and 10.7% (n=75) of gizzards showing no evidence of penetration wounds. Ingestion is likely related to grit size preferences that are consistent with common shot sizes. The second chapter describes watering patterns and water-site selection of Chukars. Chukars watered during daylight hours with a modal hour from 1100 hours to 1200hours. Annual patterns suggest no use of water sources from November to May with first visits occurring in June of each year and last visits in October. Shrub canopy cover was the only variable to discriminate between use and non-use watering sources (P < 0.01). Cross validation showed a predictive success rate of 84%. Significant differences were found between use and non-use sites in terms of protective cover (P < 0.01), but not total cover (P > 0.05). Chukars were found to have a shrub canopy threshold near 11%; water sources meeting this threshold received use, whereas those not meeting this threshold did not. Chapter three challenges several claims postulating negative conservation implications relative to exotic Chukars in North America. These claims were proven to be unfounded with no evidence of cheatgrass (Bromus tectorum) dispersal despite widespread utilization. Furthermore, guzzlers designed to benefit Chukar populations were heavily utilized by native species and only slightly (two species at three sites) by other exotics. These three manuscripts illuminate several areas of Chukar ecology and represent a significant advancement in our understanding of this bird and its management.
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