The Role of Free-ranging Mammals in the Deposition of Escherichia coli into a Texas Floodplain
Free-ranging wildlife are an important contributor of fecal pollution in the form of Escherichia coli (E. coli) to water bodies. Currently, details of this contribution are nebulous and understudied. Much of the related research has not focused on freeranging wildlife; instead investigations examine entire systems while estimating wildlife contribution indirectly or with data of inconsistent quality and source. I began my research by conducting a meta-analysis of existing research to determine the current state of knowledge of wildlife?s specific contribution. Data were sparse, fragmented, of variable quality, and difficult to access. Researchers relied on a variety of outside sources (e.g., state natural resource agencies). Making comparison between studies was nearly impossible because methodologies differed greatly or were described inconsistently. I then calculated wildlife population densities, undertook fecal collection, and conducted spatial analyses of fecal deposition to gather accurate and relevant data of the study area. I augmented field data collection with data derived from my meta-analysis (i.e., fecal deposition rates). I was able to estimate the relative role of individual species (e.g., raccoons [Procyon lotor], white-tailed deer [Odocoileus virginianus], and feral hogs [Sus scrofa]). Finally, I created a model using these data to determine important parameters for future research (e.g., fecal deposition rates) and simulate various management strategies. Although all parameters need more research focus, I found defecation rates were especially important but little researched. I found raccoons were the greatest determiner of potential E. coli load in the floodplain though adjustment of other parameters would greatly impact these findings.