2026-09-18T23:02:17Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/120215 2023-09-04 col_2142_5131 col_2142_14737 com_2142_5130 com_2142_690 com_2142_397

Schooley , Robert L Miller, James R Benson, Thomas J Cosentino, Bradley J 2023-05 application/pdf en text Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms The student, Casey Wagnon, accepted the attached license on 2023-03-16 at 07:12. The student, Casey Wagnon, submitted this Dissertation for approval on 2023-03-16 at 07:22. This Dissertation was approved for publication on 2023-03-16 at 11:38. DSpace SAF Submission Ingestion Package generated from Vireo submission #18880 on 2023-09-01 at 17:07:32 Dryland state transitions, trophic interactions, and the restoration of a keystone species Wagnon, Casey John 2023-03-16 Drylands Shrub Encroachment Habitat Restoration Trophic Interactions Landscape Of Fear Animal Personality Keystone Species Structural Equation Modeling Lagomorphs Canids Chihuahuan Desert Shrub encroachment is a global driver of ecosystem change impacting grass-dominated drylands, with consequences for trophic interactions. Such state transitions have prompted shrub removal efforts in attempts to reverse the process and restore encroached grasslands. However, we lack adequate understanding of how trophic food webs respond to shrub encroachment or how habitat restoration actions impact animal behavior, including shrub removal. My research examined how shrub encroachment and grassland restoration efforts in the Chihuahuan Desert of New Mexico shapes the trophic and behavioral ecology of mammals. I first evaluated how shrub encroachment affects trophic interactions and the landscape of fear in a canid-lagomorph system. Lagomorph prey responded strongly to bottom-up pulses during years of high summer precipitation but only on sites with moderate to high shrub cover. This outcome is inconsistent with the hypothesis that bottom-up effects should be strongest in grasslands because of greater herbaceous food resources. Instead, this pattern is consistent with changes in the landscape of fear because perceived predation risk in lagomorphs is reduced in shrub-dominated habitats. I then examined the behavioral response of a keystone rodent of grasslands, Dipodomys spectabilis, to extensive shrub removal efforts by comparing personality traits and movement behavior between restoration and remnant habitats. Personality traits were present in D. spectabilis but did not strongly differ between environments. Notably, D. spectabilis exhibited personality-dependent movement through artificial shrubs in a movement experiment, suggesting a mechanistic pathway affecting colonization dynamics of shrub removal sites. My research reveals the varied and complex ways that wildlife populations may respond to ecosystem change in drylands. Future research should consider the landscape of fear and animal personality when evaluating wildlife responses to global change drivers and habitat restoration. Thesis eng https://hdl.handle.net/2142/120215 Copyright 2023 Casey Wagnon Ph.D. Dissertation Natural Res & Env Sciences University of Illinois at Urbana-Champaign Natural Res & Env Sci