60 research outputs found

    UACI: Uncertain Associative Classifier for Object Class Identification in Images

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    Abstract Uncertainty is inherently present in many real-worl

    Exploring Animal Behavior Through Sound: Volume 1

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    This open-access book empowers its readers to explore the acoustic world of animals. By listening to the sounds of nature, we can study animal behavior, distribution, and demographics; their habitat characteristics and needs; and the effects of noise. Sound recording is an efficient and affordable tool, independent of daylight and weather; and recorders may be left in place for many months at a time, continuously collecting data on animals and their environment. This book builds the skills and knowledge necessary to collect and interpret acoustic data from terrestrial and marine environments. Beginning with a history of sound recording, the chapters provide an overview of off-the-shelf recording equipment and analysis tools (including automated signal detectors and statistical methods); audiometric methods; acoustic terminology, quantities, and units; sound propagation in air and under water; soundscapes of terrestrial and marine habitats; animal acoustic and vibrational communication; echolocation; and the effects of noise. This book will be useful to students and researchers of animal ecology who wish to add acoustics to their toolbox, as well as to environmental managers in industry and government

    Exploring Animal Behavior Through Sound: Volume 1

    Get PDF
    This open-access book empowers its readers to explore the acoustic world of animals. By listening to the sounds of nature, we can study animal behavior, distribution, and demographics; their habitat characteristics and needs; and the effects of noise. Sound recording is an efficient and affordable tool, independent of daylight and weather; and recorders may be left in place for many months at a time, continuously collecting data on animals and their environment. This book builds the skills and knowledge necessary to collect and interpret acoustic data from terrestrial and marine environments. Beginning with a history of sound recording, the chapters provide an overview of off-the-shelf recording equipment and analysis tools (including automated signal detectors and statistical methods); audiometric methods; acoustic terminology, quantities, and units; sound propagation in air and under water; soundscapes of terrestrial and marine habitats; animal acoustic and vibrational communication; echolocation; and the effects of noise. This book will be useful to students and researchers of animal ecology who wish to add acoustics to their toolbox, as well as to environmental managers in industry and government

    A behavioral ecology of shermen: hidden stories from trajectory data in the Northern Humboldt Current System

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    This work proposes an original contribution to the understanding of shermen spatial behavior, based on the behavioral ecology and movement ecology paradigms. Through the analysis of Vessel Monitoring System (VMS) data, we characterized the spatial behavior of Peruvian anchovy shermen at di erent scales: (1) the behavioral modes within shing trips (i.e., searching, shing and cruising); (2) the behavioral patterns among shing trips; (3) the behavioral patterns by shing season conditioned by ecosystem scenarios; and (4) the computation of maps of anchovy presence proxy from the spatial patterns of behavioral mode positions. At the rst scale considered, we compared several Markovian (hidden Markov and semi-Markov models) and discriminative models (random forests, support vector machines and arti cial neural networks) for inferring the behavioral modes associated with VMS tracks. The models were trained under a supervised setting and validated using tracks for which behavioral modes were known (from on-board observers records). Hidden semi-Markov models performed better, and were retained for inferring the behavioral modes on the entire VMS dataset. At the second scale considered, each shing trip was characterized by several features, including the time spent within each behavioral mode. Using a clustering analysis, shing trip patterns were classi ed into groups associated to management zones, eet segments and skippers' personalities. At the third scale considered, we analyzed how ecological conditions shaped shermen behavior. By means of co-inertia analyses, we found signi cant associations between shermen, anchovy and environmental spatial dynamics, and shermen behavioral responses were characterized according to contrasted environmental scenarios. At the fourth scale considered, we investigated whether the spatial behavior of shermen re ected to some extent the spatial distribution of anchovy. Finally, this work provides a wider view of shermen behavior: shermen are not only economic agents, but they are also foragers, constrained by ecosystem variability. To conclude, we discuss how these ndings may be of importance for sheries management, collective behavior analyses and end-to-end models.Tesis (Doctorat). -- Universite de Montpellier IIIRD / IMARP

    Woodland soundscapes: Investigating new methods for monitoring landscapes

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    Biodiversity is an important provider of ecosystem services. There is a sense of urgency running through the scientific community regarding its protection and conservation. This urgency is fuelled by a wealth of research into the effects of habitat destruction, intensive agriculture, destructive industries (such as mining and oil exploration) and the insidious threat of climate change. It might reasonably be suggested that the biodiversity crisis we are facing today is in large part due to a lack of regulation around human-activities with regard to biodiversity impacts. In order to impose regulations, protecting biodiversity has been incentivised through various governmental and non-profit private-sector certification initiatives that aim to minimise the negative impacts that industry can have on the environment. Agri-environment schemes are largely governmental initiatives that aim to enhance the biodiversity and societal values of farmland. Timber certification initiatives, such as the Forest Stewardship Council, promote woodland management that takes into account the economic, environmental and social aspects of forestry with equal measure. Protection and enhancement of biodiversity is integral to achieving the environmental aims of certification. However, several studies have highlighted that many schemes (notably agri-environment schemes and some timber certification schemes) ultimately fall short of their projected targets, which is often due to a lack of suitable monitoring with regard to biodiversity. This is unsurprising since biodiversity monitoring is not a straightforward process. Many considerations need to be made when choosing suitable indicators of ecosystem health such as whether to measure species diversity or functional diversity. But perhaps one of the biggest issues is the ability of landowners and managers to contribute to efficient, objective, standardised data collection. Acoustic monitoring offers a means of producing unbiased data that can be analysed objectively and stored indefinitely. With significant advances in hardware and software technologies, the proliferation of acoustic monitoring is evident in the scientific literature.The field of soundscape ecology was in many respects borne out of these technological advances. It has since been usurped by the newer field of ecoacoustics (I use these two terms interchangeably throughout this thesis). Ecoacoustics offers a range of soundscape analytical techniques that aim to understand the spectral and temporal composition of the soundscape. As such a number of acoustic indices can be used to measure different facets of acoustic diversity. This study offers an overview of the current literature in bioacoustics and ecoacoustics. It applies several of these indices to studying the soundscape of Forest Stewardship Council certified plantation forests in the UK. Specifically it investigates the soundscape in relation to habitat and landscape metrics and explores temporal variation in acoustic activity. It offers insights into the relationship between man-made/machine noise (technophony) and biological sounds (biophony) and suggests future directions for research and large-scale monitoring of habitats. Finally it provides a set of instructions on how to build an automated recording unit using readily available parts and provides links to necessary software and guidance on types of hardware available. The key findings indicate that the use of acoustic indices for monitoring landscapes could be a useful tool. Clear relationships were observed between forest structure and stand age, and vegetation structure, with acoustic diversity in Thetford forest over two consecutive years. Although these relationships were not clear in Bedgebury forest, the effects of landscape structure were statistically significant, particularly when using automated recording units. Road proximity had a strong influence on the soundscape in all study sites. And the use of ecoacoustic methods to explore this offers an insight into a new means of investigating the impact of roads on acoustic biodiversity. The development of a low-cost automated recording unit is a significant contribution to the field of soundscape ecology in terms of encouraging participation by the non-governmental organisation (NGO) sector. Likewise, the use of a handheld recording unit and the application of traditional ecological survey methods provide evidence that soundscape/ecoacoustic studies that yield interesting, informative and biologically meaningful results can be done on a relatively low budget. As such this thesis offers a significant contribution to the field of soundscape ecology in terms of both data and logistics. It may be particularly relevant to researchers on a limited budget and/or the NGO and citizen science sector
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