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1	THE IMPACT OF VEHICULAR NOISE ON THE EFFECTIVENESS OF ACOUSTIC INDICES Ducay, Rebecca 01 May 2024 (has links) (PDF) Passive acoustic monitoring (PAM) is a valuable tool in wildlife research, offering non-invasive and cost-effective means to collect acoustic data. However, the processing of PAM recordings can be time-consuming, prompting the use of acoustic indices to expedite analysis. Acoustic indices are numerical values that characterize biological information in sound recordings based on an environment’s acoustic characteristics. While acoustic indices have been correlated with species richness across ecological contexts, their reliability diminishes in areas with heightened vehicular noise. However, it is unclear if index biases caused by vehicular noise are consistent across all traffic levels, and which acoustic indices are most biologically informative in these human-developed contexts. I assessed the direct impact of vehicular noise on nine acoustic indices through controlled manipulation of vehicular noise within 598 computer-generated bird assemblage soundscapes. Using the bird assemblage soundscapes, I also investigated the effects of three high-pass filter treatments (482 Hz, 1 KHz, and 2 KHz) on these acoustic indices under different levels of traffic noise interference. These filtering effects were also assessed within empirical PAM recordings taken from 147 sites in southern Illinois from May into mid-July of 2022 and 220 sites across the state during late-April to mid-July of 2023. Results indicate that proximity to roads and vehicular traffic significantly affect index values, albeit to varying degrees. Four indices – Bioacoustic Index, Acoustic Complexity Index, Acoustic Diversity Index, and Acoustic Evenness Index – exhibited greater resilience to vehicular noise and may be better suited for urban environments. Notably, the Acoustic Diversity Index, Acoustic Evenness Index, and the Number of Frequency Peaks also displayed consistent species richness estimations regardless of vehicular noise level. While filtering had variable interactive effects with vehicular noise, no consistent benefits of filtering were observed across all indices. Nevertheless, the Acoustic Complexity Index, Acoustic Richness Index, and CityBioNet displayed minimal biases when high-pass filters were applied, and CityBioNet demonstrated particularly high correlations with species richness. These findings underscore the importance of understanding index behavior under anthropogenic noise and different filtering methodologies. My findings serve to inform acoustic index implementation within acoustic monitoring efforts, thus expanding access and reliability of these methodologies within human-developed environments. acoustic indices anthrophony audio filtering avian monitoring passive acoustic monitoring soundscapes
2	Soundscape dynamics in the social-ecological systems of Tierra del Fuego Dante P Francomano (9738650) 14 December 2020 (has links) <p>Human society is presently beset by an array of anthropogenic social-ecological crises that threaten the sustainability of the social-ecological systems that sustain our livelihoods. While research alone will not rectify these issues, it can help to answer key questions that must be addressed to develop effective solutions. To address such questions in a cohesive, compelling manner, social-ecological research can be bounded, structured, and distilled through innumerable organizing principles or theoretical frameworks. For this dissertation, I focused on the geographic region of Tierra del Fuego and sought to draw from the array of disciplines and methods that use sound as a lens for biological, ecological, and/or social inquiry. I also endeavored to consider various temporal, spatial, and organizational scales while investigating a selection of topics with a) specific importance in the social-ecological systems of Tierra del Fuego and b) general relevance to global social-ecological challenges. Chapter 1 provides an introduction to the dissertation, and Chapter 6 serves as a conclusion.</p><p><br></p><p> </p><p>The objective of Chapter 2, “Biogeographical and analytical implications of temporal variability in geographically diverse soundscapes”, was to provide some guidance to passive acoustic monitoring (PAM) practitioners on how to design appropriate temporal sampling schemes based on the temporal variability of the sounds one wishes to measure and the power and storage limitations of acoustic recorders. We first quantified the temporal variability of several soundscape measurements and compared that variability across sites and times of day. We also simulated a wide range of temporal sampling schemes in order to model their representativeness relative to continuous sampling.</p><p><br></p><p> </p><p>For Chapter 3, “Sentinels for sentinels: passive acoustic and camera trap monitoring of sensitive penguin populations”, we tested the utility of PAM to monitor behavior and abundance of Magellanic (<i>Spheniscus magellanicus</i>) and southern rockhopper penguins (<i>Eudyptes chrysocome</i>) at different spatial and temporal scales. We conducted <i>in situ</i> observations of the acoustic behavior of each species, and we compared acoustic metrics with penguin counts from narrowly focused camera traps and larger-extent observations of colony density. </p><p><br></p><p> </p><p>Chapter 4, “Acoustic monitoring shows invasive beavers (<i>Castor canadensis</i>) increase avian diversity in Tierra del Fuego”, is focused on impacts of the invasive North American beaver (<i>Castor canadensis</i>) on Fuegian bird communities. We sought to determine how bird communities might differ between intact riparian forests, beaver ponds, and beaver meadows created by pond drainage. We conducted PAM and classic avian point counts under each of these conditions across seasons to test for differences between impact conditions and to compare the two methodologies.</p><p><br></p><p> </p>For Chapter 5, “Human-nature connection and soundscape perception: insights from Tierra del Fuego, Argentina”, we evaluated the relationship between soundscape perception and nature relatedness by conducting surveys and soliciting responses to soundscape audio prompts. We also examined the potential for any demographic influences on nature relatedness or soundscape perception in the context of local social tensions. Environmental Science Ecology Ecosystem Function Invasive Species Ecology Conservation and Biodiversity Environmental Education and Extension Environmental Management Environmental Monitoring Natural Resource Management Wildlife and Habitat Management Psychology not elsewhere classified Behavioural Ecology Population Ecology Terrestrial Ecology Animal Behaviour Global Change Biology soundscape soundscape ecology ecoacoustics Tierra del Fuego Argentina Patagonia penguin beaver bird community species diversity functional diversity passive acoustic monitoring acoustic metrics acoustic indices soundscape perception nature relatedness connection to nature temporal variability survey exotic species camera trap study design temporal dynamics Spheniscus magellanicus Eudyptes chrysocome Castor canadensis biological invasion Ushuaia

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THE IMPACT OF VEHICULAR NOISE ON THE EFFECTIVENESS OF ACOUSTIC INDICES

Soundscape dynamics in the social-ecological systems of Tierra del Fuego