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oai:www.ideals.illinois.edu:2142/83111 2023-07-11 col_2142_5131 col_2142_14737 com_2142_5130 com_2142_690 com_2142_397

Warner, Richard E. Davis, Ronald W. 2015-09-25T21:00:33Z 2015-09-25T21:00:33Z 10000-01-01 2005 2005 "Declining habitat quality has been implicated in population declines in elk (Cervus elaphus) in the Pacific Northwest (PNW) although specific causes are unknown. Nutrition and summer-autumn body condition (percent body fat) have been linked to virtually every aspect of successful ungulate reproduction and productivity; however, many existing habitat evaluations discount the role of nutrition and are unlikely to detect changes in habitat nutritional quality. I applied an algorithm linking the biomass of suitable elk forage (BSF) and dietary digestibility (DD) to model habitat quality for elk at 3 sites in the PNW: 1 in western Oregon (Wendling), 1 in southwestern Washington (Pe Ell), and 1 in northwestern Washington (Nooksack). BSF was best predicted by overstory canopy cover (R2&ge;0.70) and I developed remote sensing-based maps of canopy cover (accuracy &ge;74%) to characterize DD levels at each site. In a GIS, I estimated habitat quality for the overall landscape, and within actual wild elk homeranges. I compared model predictions to autumn fat levels in free-ranging lactating elk. Wendling (DD=55.9%, n=14, SE=0.02) and Pe Ell (DD=55.8% n=19, SE=0.02) afforded only ""marginal"" habitat quality while Nooksack (DD=61.8%, n=19, SE=0.05) had significantly higher quality (P<0.0001). Fat levels in wild elk corresponded to ""marginal"" levels at Wendling (10.8% fat, n=10, SE=0.65) and ""good"" levels at Nooksack (13.6% fat, n=8, SE=0.45). Pe Ell elk (6.1% fat, n=9, SE=0.54) were below ""marginal"" levels but also had the highest density of wild elk (5 elk/km2) indicating a potential negative feedback between density and condition. I compared BSF/DD predictions to those of 2 forage based and 4 HSI/HEI-type elk habitat models and compared these to wild elk condition BSF/DD models detected marked differences in habitat capacity among sites and accurately predicted elk condition. Forage based models overestimated habitat capacity at all sites (P&le;0.001). HSI/HEI-type models did not did not reveal any reliable trends in habitat capacity or wild elk condition at these sites. Hence, habitat evaluation and management focused on road closures, forage-to-cover ratios, or total forage biomass are unlikely to address elk nutritional condition." Made available in DSpace on 2015-09-25T21:00:33Z (GMT). No. of bitstreams: 2 license.txt: 4848 bytes, checksum: 96035ab3f5e1c23cc7138a224ce498bd (MD5) 3202083.pdf: 2637806 bytes, checksum: 6352a6001e46564bd52f50cadc0afe05 (MD5) Previous issue date: 2005 Embargo set by: Seth Robbins for item 84392 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs U of I Only 117 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2005. http://hdl.handle.net/2142/83111 (MiAaPQ)AAI3202083 eng Agriculture, Forestry and Wildlife A Gis-Based Habitat Model Predicting Elk Nutritional Condition in the Pacific Northwest text Natural Resrouces and Environmental Sciences Natural Resrouces and Environmental Sciences University of Illinois at Urbana-Champaign Dissertation Ph.D.