Term of Award

Fall 2014

Degree Name

Master of Science in Biology (M.S.)

Document Type and Release Option

Thesis (open access)

Department

Department of Biology

Committee Chair

Lance McBrayer

Committee Member 1

David Rostal

Committee Member 2

Michelle Cawthorn

Abstract

The negotiation of uneven and complex terrain has implications for many small terrestrial vertebrates. Variation in the running surface due to obstacles like woody debris or vegetation can alter escape paths and running performance. Additionally, these microhabitat features can influence behavioral tactics in complex environments. The ability to negotiate physical barriers in dense environments likely influences survivorship through important ecological tasks, such as finding mates, foraging, and evading predators. The Florida scrub lizard (Sceloporus woodi) is a small, rare species endemic to two distinct and structurally complex environments in Florida, i.e. sand-pine scrub and longleaf pine-wiregrass sand-hills. The differing microhabitats of scrub and longleaf pine factor into the distribution and density of lizard populations throughout the Ocala National Forest in Florida. Understanding strategies to avoid predation between these two habitats can give insight into the likelihood of population persistence, and whether one habitat may harbor a greater lizard density. Additionally, the underlying performance impacts from habitat structure (e.g. multiple obstacles) can shed light on any unique abilities in small terrestrial lizard species. In the first chapter I focus on how multiple obstacles influence running behavior and locomotor posture. Bipedal running was more efficient for crossing obstacles via faster sprint speeds and minimal foot contact with an obstacle. The second chapter investigates the populations of scrub lizards in both the scrub and longleaf habitats. I determine how risk behaviors vary between habitats, and quantify the detectability and condition of lizards in each. Longleaf pine lizards had greater flight and detection distance than in sand pine scrub. Males showed greater risk aversion and were easier to detect than females in both habitats, indicating that they may be more sensitive to predation when conspicuously occupying open areas. Overall this study reveals areas in need of consideration with habitat management in the Ocala National Forest. Studies such as this help provide a mechanistic understanding of dispersal ability, habitat avoidance, and behavioral flexibility in this rare species, which may be useful to land managers and conservation biologists.

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