Date of Award


Publication Type

Master Thesis

Degree Name



Biological Sciences

First Advisor

M'Closkey, R. T.,


Biology, Ecology.



Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.


I investigated habitat use within an assemblage of four phrynosomatine lizards (Sceloporus graciosus, S. undulatus, Urosaurus ornatus, and Uta stansburiana) that are commonly syntopic in the pinyon-juniper woodland habitat on the elevated mesas of western Colorado. Lizard populations were censused within Colorado National Monument, U.S.A., during the summer months of 1989, 1990, 1991, 1992, 2000 and 2001. Microhabitat characteristics surrounding capture points were recorded in 1990, 1992 and 2000, and captures were classified into one of two distinct habitats in 2001. All four species used dead trees more frequently than live trees, despite an opposite pattern of availability. Overall density of the lizard community in 2001 was much greater in rock habitats, which were associated with numerous deadfalls, than in surrounding flatland habitats containing more live than dead vegetation. Despite observed preferences and associations with dead vegetation and rock habitats, all four species coexist in both rock and flatland habitats. I examined microhabitat use as a possible explanation for their broad syntopy. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2002 .J35. Source: Masters Abstracts International, Volume: 41-04, page: 1007. Adviser: R. T. M'Closkey. Thesis (M.Sc.)--University of Windsor (Canada), 2002.