Demographic, Spatial, and Epigenetic Response of the Louisiana Waterthrush (Parkesia Motacilla) to Shale Gas Development

Abstract

My study centered on a bioindicator songbird, the Louisiana Waterthrush (Parkesia motacilla), hereafter waterthrush, an organism that co-occurs in both forested and aquatic habitat across the aquatic-terrestrial interface. This enabled the opportunity to quantify demographic, spatial, and epigenetic (i.e., DNA methylation) responses in a highly forested watershed of the Central Appalachians, the areas that have undergone the most rapid transformations over the last decade from unconventional shale gas development and activities. I organized my dissertation into 4 parts (Part 1: Introduction, Part 2: Louisiana Waterthrush Demography, Part 3: Spatial Assessment of Louisiana Waterthrush Foraging, Part 4: Louisiana Waterthrush Molecular Ecology) including 6 chapters that indicate multiple biotic and abiotic factors interacted with or were altered by shale gas development resulting in atypical, negative disturbances that drove a steep decline in a waterthrush population in West Virginia. Part 1 includes Chapter 1 and is an introduction to my dissertation. I introduce the reader to the rationale for my study, the focal species, research objectives, and the study area. I also mention some limitations to my study that can be considered in any future research endeavors. Part 2 comprises Chapters 2-3 which are a comprehensive examination of demographic parameters over a six-year period (2009-2011, 2013-2015). In Chapter 2, I examined demographic response to shale gas development for nest abandonment, nest survival, nest productivity, a source-sink threshold, riparian habitat quality, and territory density and length. Nest productivity was lower in areas disturbed by shale gas where a source-sink threshold suggested these areas were more at risk of being sink habitat. Overall results suggest a decline in waterthrush site quality as shale gas development increased. In Chapter 3, I focused on first-year return rates (site fidelity), site fidelity factors, and apparent survival. I related natal fidelity and pairing rates to territory density, and also compared # of breeding attempts between return and non-returning females with and without territory shale gas disturbance. The study identified potential conflicts between factors that influence adult survival and site fidelity that may affect long-term population persistence. Part 3 includes Chapters 4-5 and focuses on utilizing and accounting for spatial properties intrinsic to stream ecosystems to make informed decisions regarding waterthrush foraging. Chapter 4 was a follow-up to a waterthrush aquatic prey study at our site in 2011 that suggested shale gas development negatively affected waterthrush demography from alterations in their aquatic prey at a watershed scale. During 2013-2014, I quantified waterthrush demographic response and nest survival in relation to potential changes in its aquatic prey due to shale gas development. I utilized spatial generalized linear mixed models that accounted for both spatial and non-spatial sources of variability. I found waterthrush aqu...