An automated, real time classification system for biological and anthropogenic sounds from fixed ocean observatories

The automated, real time classification of acoustic events in the marine environment is an important tool to study anthropogenic sound pollution, marine mammals and for mitigating human activities that are potentially harmful. We present a real time classification system targeted at many important groups of acoustic events (clicks, buzzes, calls, whistles from several cetacean species, tonal and impulsive shipping noise and explosions). The achieved classification performance indicates that the system will be useful to pre-process the very large data volume that can be gathered during long term acoustic monitoring campaigns or to detect the presence of cetaceans in real time for mitigation.Peer Reviewe

Architecture for the real-time monitoring of noise pollution and marine mammal activity

As acoustic pollution in the oceans is increasing, it is becoming more important to monitor it, with special attention on its effects on the behaviour of cetaceans. In the near future governments may require constant monitoring during sea construction projects or operations. One major construction activity in the coming years will be the construction of wind farms. Not only will these farms produce a constant low level noise in their direct environment while operating, but the building of the foundations necessary to support the wind mills will produce impulsive noise dangerous to any cetaceans in the area and lethal to, for example, fish larvae. For these reasons, noise monitoring has become one of the objectives of the European Seafloor Observation Network (ESONET), to investigate the level of noise produced around European coastlines and its impact on the environment and cetaceans especially. Presented is the architecture for noise and marine mammal monitoring as it is currently implemented in ESONET through the LIDO (Listening to the Deep Ocean Environment) project. LIDO will detect in real-time changes in the background noise levels and register acoustic events (natural, biological and anthropogenic), and identify and track the sources when possible. As the system will be implemented in varying environments, a modular design is used that can be adapted easily, based on local requirements. While the system will most often run from a shore station, a more limited version is developed that can run autonomously with minimal power requirements.Peer Reviewe

Modeling the underwater noise associated to the construction and operation of offshore wind turbines

The operation and in particular the construction of offshore wind converters induce considerable underwater noise emissions. It is assumed that small whales and seals can be affected by noise from machines and vessels, piling and installation of the wind turbines. Piling, in particular using hydraulic hammers creates impulsive noise with considerable high energy levels. Currently, only little knowledge about the effects of different noises to marine life is available. Here, we present the objectives of the ongoing project of the Laboratory of Applied Bioacoustics (Technical University of Catalonia): to simulate the generation, radiation and propagation of underwater noise; to develop forecasting hydro sound models of offshore wind converters and future noise reduction methods during pile driving; to determine the impact area of offshore wind farms; to allow the formulation of recommendations for acoustic emission thresholds; and to develop standard procedures for the determination and assessment of noise emissions.Peer Reviewe

Modelling the underwater noise associated to the construction and operation of offshore wind turbines

The operation and in particular the construction of offshore wind converters induce considerable underwater noise emissions. It is assumed that small whales and seals can be affected by noise from machines and vessels, piling and installation of the wind turbines. Piling, in particular using hydraulic hammers creates impulsive noise with considerable high energy levels. Currently, only little knowledge about the effects of different noises to marine life is available. Here, we present an ongoing project from the Laboratory of Applied Bioacoustics (Technical University of Catalonia): to simulate the generation, radiation and propagation of underwater noise; to develop forecasting hydro sound models of offshore wind converters and future noise reduction methods during pile driving; to determine the impact area of offshore wind farms; to allow the formulation of recommendations for acoustic emission thresholds; and to develop standard procedures for the determination and assessment of noise emissions.Peer ReviewedPostprint (published version

Best practices in management, assessment and control of underwater noise pollution

The origin of this work can be found in the project ‘Effects and Control of Anthropogenic Noise in Marine Ecosystems’ in the part relative to legal initiatives. In the first phase of the Report on this Project (December 2008) it was concluded that the level of complexity of marine issues, united by the fact that wide scientific gaps and difficulties still need to be covered and resolved, counseled against the immediate drawing up of legal projects concerning underwater acoustic pollution. Nevertheless, it was suggested that a document of ‘Best Practices’ be elaborated to focus on the ‘state of the art’ of this issue, and that it be used by public administrations and promoters of projects that will cause acoustic pollution, as much within the framework of environmental impact assessments as in management development plans in protected marine areas. It is of vital importance that activities, which generate acoustic pollution in the oceans, be monitored. Accordingly, this document could derive, in the short term, a Protocol of Applications which will in its own time open the way for the preparation of, if necessary, legislative initiatives within their own right.Preprin

Space–time and hybrid algorithms for the passive acoustic localisation of sperm whales and vessels

In the frame of the European Sea-floor Observatory Network (ESONET) and in preparation of the Demonstration Mission Listening to the Deep-Ocean Environment (LIDO) algorithms for the automated real-time detection, classification and localisation of cetaceans have been developed. Such Passive Acoustic Monitoring techniques have the potential to play a key role in cetaceans’ conservation for they allow a non-invasive study of their behaviour, a better knowledge of their population dynamics, and a better understanding of their dynamic relationship with their environment. This paper investigates the development of efficient and accurate techniques to be used as the basis of a localisation module for an automated real-time Passive Acoustic Monitoring system. An opportunity to assess the capabilities of the developed localisation modules was given by recordings collected with a bottom-mounted (around 2080 m depth) tetrahedral compact hydrophone array located offshore the port of Catania (Sicily) during the NEMO-ONDE campaign in the years 2005–2006 by INFN and CIBRA [2]. A well-known class of methods for acoustic source localisation is based on time differences of arrival (TDOA). Its capabilities have shown to be useful even in adverse situations (i.e., few sensors, high noise levels and/or poor calibration). A second class of methods, the space–time methods, originated in underwater applications such as sonar but reached its most significant achievements over the last 20 years in digital communications with recent progress in the treatment of broadband signals. These developments are here revisited under the scope of the localisation and tracking of cetacean vocalisations. Various broadband space–time methods were implemented and allowed to map the sound radiated during the detected clicks and to consequently localise both sperm whales and vessels. Hybrid methods were also developed which improved the robustness of space–time methods to noise and reverberation and reduced processing time. In most cases, the small variance obtained for these estimates lessened the necessity of additional statistical clustering. Even though not independently confirmed by sightings, the tracks derived in the proposed frame can be considered to be consistent with the known movements of sperm whales and vessels.Peer Reviewe

Architecture for the real-time monitoring of noise pollution and marine mammal activity

As acoustic pollution in the oceans is increasing, it is becoming more important to monitor it, with special attention on its effects on the behaviour of cetaceans. In the near future governments may require constant monitoring during sea construction projects or operations. One major construction activity in the coming years will be the construction of wind farms. Not only will these farms produce a constant low level noise in their direct environment while operating, but the building of the foundations necessary to support the wind mills will produce impulsive noise dangerous to any cetaceans in the area and lethal to, for example, fish larvae. For these reasons, noise monitoring has become one of the objectives of the European Seafloor Observation Network (ESONET), to investigate the level of noise produced around European coastlines and its impact on the environment and cetaceans especially. Presented is the architecture for noise and marine mammal monitoring as it is currently implemented in ESONET through the LIDO (Listening to the Deep Ocean Environment) project. LIDO will detect in real-time changes in the background noise levels and register acoustic events (natural, biological and anthropogenic), and identify and track the sources when possible. As the system will be implemented in varying environments, a modular design is used that can be adapted easily, based on local requirements. While the system will most often run from a shore station, a more limited version is developed that can run autonomously with minimal power requirements.Peer Reviewe

Space–time and hybrid algorithms for the passive acoustic localisation of sperm whales and vessels

In the frame of the European Sea-floor Observatory Network (ESONET) and in preparation of the Demonstration Mission Listening to the Deep-Ocean Environment (LIDO) algorithms for the automated real-time detection, classification and localisation of cetaceans have been developed. Such Passive Acoustic Monitoring techniques have the potential to play a key role in cetaceans’ conservation for they allow a non-invasive study of their behaviour, a better knowledge of their population dynamics, and a better understanding of their dynamic relationship with their environment. This paper investigates the development of efficient and accurate techniques to be used as the basis of a localisation module for an automated real-time Passive Acoustic Monitoring system. An opportunity to assess the capabilities of the developed localisation modules was given by recordings collected with a bottom-mounted (around 2080 m depth) tetrahedral compact hydrophone array located offshore the port of Catania (Sicily) during the NEMO-ONDE campaign in the years 2005–2006 by INFN and CIBRA [2]. A well-known class of methods for acoustic source localisation is based on time differences of arrival (TDOA). Its capabilities have shown to be useful even in adverse situations (i.e., few sensors, high noise levels and/or poor calibration). A second class of methods, the space–time methods, originated in underwater applications such as sonar but reached its most significant achievements over the last 20 years in digital communications with recent progress in the treatment of broadband signals. These developments are here revisited under the scope of the localisation and tracking of cetacean vocalisations. Various broadband space–time methods were implemented and allowed to map the sound radiated during the detected clicks and to consequently localise both sperm whales and vessels. Hybrid methods were also developed which improved the robustness of space–time methods to noise and reverberation and reduced processing time. In most cases, the small variance obtained for these estimates lessened the necessity of additional statistical clustering. Even though not independently confirmed by sightings, the tracks derived in the proposed frame can be considered to be consistent with the known movements of sperm whales and vessels.Peer Reviewe

Contribution to unravel variability in bowhead whale songs and better understand its ecological significance

Since the first studies on bowhead whale singing behaviour, song variations have been consistently reported. However, there has been little discussion regarding variability in bowhead whale singing display and its ecological significance. Unlike the better studied humpback whales, bowhead whales do not appear to share songs at population level, but several studies have reported song sharing within clusters of animals. Over the winter season 2013–2014, in an unstudied wintering ground off Northeast Greenland, 13 song groups sharing similar hierarchical structure and units were identified. Unit types were assessed through multidimensional maps, showing well separated clusters corresponding to manually labelled units, and revealing the presence of unit subtypes. Units presented contrasting levels of variability over their acoustic parameters, suggesting that bowhead whales keep consistency in some units while using a continuum in values of frequency, duration and modulation parameters for other unit types. Those findings emphasise the need to account for variability in song analysis to better understand the behavioural ecology of this endangered species. Additionally, shifting from song toward units or phrase-based analysis, as it has been suggested for humpback whales, offers the opportunity to identify and track similarities in songs over temporal and geographical scales relevant to population monitoring.Peer ReviewedPostprint (published version

A guide to standards relating to bulk materials handling

Available from British Library Document Supply Centre- DSC:7628.85(WSL-LR--640(MH)) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo