“Evolution has shaped the characteristics of species in ways that result in scale displacement. Each species experiences the environment at its own unique set of spatial and temporal scales and interfaces the biota through unique assemblages of phenotypes. In this way, coexistence becomes possible, and biodiversity is enhanced. By averaging over space, time, and biological interactions, a genotype filters variation at fine scales and selects the arena in which it will face the vicissitudes of nature.” —Simon A. Levin and Stephen W. Pacala 1997 The decline of northern bobwhite (Colinus virginianus) populations across North America has stimulated much conservation, management, and research interest. Numerous land use practices have altered the structure of the landscape on which bobwhites occur. This has resulted in a shift in scale of the ultimate and proximate factors that influence bobwhite populations from traditionally smaller scales to broader landscape-scales. This has necessitated a corresponding shift in the scale at which we collect and analyze ecological data on bobwhites and manage their habitat and populations. This research suggests that bobwhite managers may not possess the required knowledge to adequately apply concepts in landscape ecology to the research and management of bobwhite. In Chapter I, I review these concepts and posit ways in which biologists can better integrate the concepts of landscape ecology to the population dynamics of bobwhites. I suggest that an ideal technique to introduce biologists to landscape ecology is through spatially explicit modeling. Chapter II represents an application of spatially explicit modeling using landscape heterogeneity, weather, and other geomorphic factors to predict bobwhite abundance. My results indicate that precipitation—believed to be an important factor influencing population dynamics—only partially explains the spatial abundance of bobwhites. The spatial configuration of grassland and bare-ground cover-types influenced the abundance of bobwhites. Small-scale factors like harvest, livestock grazing, prescribed fire, and brush management across large spatial extents also profoundly influenced bobwhite population dynamics. I developed a relational database of these factors and used a linear model to identify univariate relationships with abundance. Chapter III outlines these relationships and attempts to consolidate precisely how these practices influence abundance at multiple scales.
August 31, 2015
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