Date of Award
Program or Major
Master of Science
Salt marsh habitats are prevalent throughout coastal New England and offer a wide rangeof ecological services, including serving as nursery habitats to both transient and resident species, trapping sediment and nutrients to keep pace with rising sea levels, and improving water quality through filtration of runoff. These complex habitats remain poorly understood, especially regarding the biological communities that occupy them. The northern temperate salt marshes that characterize the coast of Northern New England contain northern temperate salt marsh pools (NTSPs) that serve as important wildlife habitats with unique abiotic conditions and biotic communities. The isolated nature of these pools from their estuary mainland, with the exception of inputs from infrequent tidal flooding, allows them to be characterized as islands in the context of island biogeography theory. Here, I assess two island biogeography variables, island size (pool volume) and connectivity (distance of pools from a tidal creek), to determine their effect on the abundance, species richness, and biodiversity of NTSPs. Data from this study indicated that NTSP size is positively correlated with both organism abundance and species richness, while NTSP connectivity is correlated with biodiversity. The monitoring of ecosystems using passive acoustic techniques has gained increasing popularity in recent years, as it is cost effective, and less time intensive than traditional biodiversity surveys. To expedite the process of analyzing recordings, many acoustic indices have been developed to analyze soundscape recordings. During this study, I used passive acoustic methods to monitor 20 NTSPs during the summer of 2021 to determine whether acoustic indices in the R packaged soundecology and seewave (H, BIO, ACI, ADI, AEI, and NDSI) highlight relationships between NTSP soundscapes with the abundance, species richness, and/or biodiversity of their inhabitants. This analysis determined that the AEI index had the strongest correlation with organism abundance and species richness, while only the maximum values produced by the BIO index correlated with NTSP biodiversity. This analysis also determined that the abiotic variable pool volume was positively correlated with ACI and AEI index values, as well as maximum values from the BIO index. While correlations between both biotic and abiotic variables and acoustic indices were found, it is recommended that acoustic indices designed for aquatic use are created, as there are many differences between aquatic and terrestrial soundscapes.
Licht, Sofia Rose, "Applying Island Biogeography Theory and Ecoacoustic Approaches to Explore the Species Composition, Richness, and Biodiversity in Northern Temperate Salt Marsh Pools of the Little River Estuary" (2021). Master's Theses and Capstones. 1478.