My research project is based on the theory of habitat selection and how it can influence species occurrence. My hypothesis is that spotted towhee (Pipilo maculatus) presence is influenced by shrub cover density, which is grounded in the idea that animals will non-randomly distribute themselves over land depending on the local resource availability and environmental structure. Specifically, the ideal free distribution theory (IFD) says that animals will distribute themselves among different patches in proportion to resource availability in order to maximize their individual fitness.
My hypothesis and prediction (that towhees will more frequently occupy dense shrub cover areas) also touches on the concept of ecological niches: the match of a species to a specific environment, and species-habitat associations e.g. spotted towhees tend to prefer dry, shrubby habitats like thickets and brushy fields. Shrub cover density is one structural component of a habitat which I’m focusing on to see if it affects how frequently Pipilo maculatus (a known ground-foraging/nesting bird species) occupies a variety of sites (primarily Garry oak meadows and woodland) in an urban park. I’m looking at this categorically over a gradient of shrub cover density which allows me to see how habitat heterogeneity within a patchy urban Garry oak ecosystem can shape the distribution of spotted towhees. Habitats with dense shrub cover are more structurally complex and therefore may provide more opportunities for nesting sites, foraging, and physical protection from predation by other animals living in the same environment. These are important considerations for wildlife management and conservation in urban parks, especially for those like Beacon Hill park with a focus on preserving and protecting sensitive ecosystems/species.
Three keywords I could use to describe my research are:
-Urban gradient
-Shrub density
-Habitat selection