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  • Mosaics For Nephrops Detection in Underwater Survey Videos

    Sooknanan, K; Doyle, J; Lordan, C; Wilson, J; Kokaram, A; Corrigan, D (2014)
    Harvesting the commercially significant lobster, Nephrops norvegicus, is a multimillion dollar industry in Europe. Stock assessment is essential for maintaining this activity but it is conducted by manually inspecting hours of underwater surveillance videos. To improve this tedious process, we propose an automated procedure. This procedure uses mosaics for detecting the Nephrops, which improves visibility and reduces the tedious video inspection process to the browsing of a single image. In addition to this novel application approach, key contributions are made for handling the difficult lighting conditions in these kinds of videos. Mosaics are build using 1-10 minutes of footage and candidate Nephrops regions are selected using image segmentation based on local image contrast and colour features. A K-Nearest Neighbour classifier is then used to select the respective Nephrops from these candidate regions. Our final decision accuracy at 87.5% recall and precision shows a corresponding 31.5% and 79.4% improvement compared with previous work.
  • Improving underwater visibility using vignetting correction

    Sooknanan, K.; Kokaram, A.; Baugh, G.; Corrigan, D.; Wilson, J.; Harte, N. (IEEE, 2012)
    Underwater survey videos of the seafloor are usually plagued with heavy vignetting (radial falloff) outside of the light source beam footprint on the seabed. In this paper we propose a novel multi-frame approach for removing this vignetting phenomenon which involves estimating the light source footprint on the seafloor, and the parameters for our proposed vignetting model. This estimation is accomplished in a bayesian framework with an iterative SVD-based optimization. Within the footprint, we leave the image contents as is, whereas outside this region, we perform vignetting correction. Our approach does not require images with different exposure values or recovery of the camera response function, and is entirely based on the attenuation experienced by point correspondences accross multiple frames. We verify our algorithm with both synthetic and real data, and then compare it with an existing technique. Results obtained show significant improvement in the fidelity of the restored images.
  • Mosaics For Burrow Detection in Underwater Surveillance Video

    Sooknanan, K.; Doyle, J.; Kokaram, A.; Corrigan, D.; Wilson, J.; Harte, N. (IEEE, 2013)
    Harvesting the commercially significant lobster,Nephrops norvegicus, is a multimillion dollar industry in Europe. Stock assessment is essential for maintaining this activity but it is conducted by manually inspecting hours of underwater surveillance videos. To improve this tedious process, we propose the use of mosaics for the automated detection of burrows on the seabed. We present novel approaches for handling the difficult lighting conditions that cause poor video quality in this kind of video material. Mosaics are built using 1-10 minutes of footage and candidate burrows are selected using image segmentation based on local image contrast. A K-Nearest Neighbour classifier is then used to select burrows from these candidate regions. Our final decision accuracy at 93.6% recall and 86.6% precision shows a corresponding 18% and 14.2% improvement compared with previous work.
  • Indexing and selection of well-lit details in underwater video using vignetting estimation

    Sooknanan, K.; Kokaram, A.; Corrigan, D.; Wilson, J.; Harte, N. (IEEE, 2012)
    Video is an important tool in underwater surveys today, yet its useful field of view is restricted to image details within well lit regions on the seafloor. In this paper we present a novel vignetting-based weighting scheme for selecting these well lit details for use in the creation of a wide area view (mosaic) of the surveyed seafloor. Apart from this detail selection novelity,two other contributions are made. Firstly, because some of these scenes contain very little image texture, we introduce a hybrid homography estimation procedure that uses both feature-based and exhaustive searching techniques. Secondly, to facilitate cross referencing with the video, sections of the mosaic were indexed with the frame number in which the respective image details was selected from. We test our algorithm with real seabed survey video, whose scientific mission was population census of the particular species of lobster, Nephrops norvegicus. High quality mosaics were obtained that captured image details from well lit regions of the scene, which expert marine biologists agreed was a useful analysis tool. This work was supported by the Science Foundation Ireland PI Programme: SFI-PI 08/IN.1/I2112, and was done in collaboration with the Marine Institute Galway.
  • Deep-sea fisheries management: the approach taken by the European Union

    Clarke, Maurice; Patterson, Kenneth (Food and Agriculture Organization of the United Nations, 2005)
    This paper outlines the approach taken by the European Union to the management of deep-sea fish stocks. An extensive range of measures was adopted in 2002, and implementation began in 2003. The scheme, which is binding on EU fishing vessels targeting deep-sea species in the North-East Atlantic, encompasses both input and output controls. In southern Europe and in the Mediterranean, deep-sea fisheries tend to be artisanal in nature, and in some cases of considerable antiquity. In northern community waters deepwater fisheries began in the 1970’s. These diverse fisheries, in several regions create particular problems for fisheries managers. The approach taken by the European Union was to adopt catch restrictions, in the form of total allowable catches for a range of the key deepwater species in the ICES area. In addition, a capacity restriction has been imposed. This requires that vessels that want to land more than a very small amount of some specified deepwater species should hold a license issued by its flag state. The overall capacity (in kilowatts and in gross tonnes) of vessels that can receive licences is limited to recent levels. The capacity limitation scheme is accompanied by a requirement to implement a scientific observer scheme in order to improve the scientific data available for assessment purposes.
  • A life history approach to the assessment of deepwater fisheries in the Northeast Atlantic

    Clarke, Maurice (Food and Agriculture Organization of the United Nations, 2005)
    It has been generally stated that deepwater fishes cannot sustain high levels of exploitation because of their characteristic slow growth, longevity and low reproductive output. However deepwater fish species display a wide variety of life-history strategies, occupying diverse positions along the K-r continuum. Literature sources provided data on age, growth, fecundity, maturity and mortality rates of several deepwater teleosts and elasmobranchs. Many teleosts displayed intermediate or conservative life-history characteristics, but the squalid sharks were more stringent K-strategists. These data were used in life-history analyses to assess the sustainability of these mixed-species deepwater fisheries. Whilst there may be scope for compensatory changes in fecundity such scope is likely to be limited, especially for sharks. The implications of these life-history parameters for sustainable exploitation are discussed by way of comparison with continental shelf species from this region.
  • Spring salmon enhancement on the Delphi Fishery, Ireland

    McDermott, T. J.; Willis, S. E.; Mantle, P. (Atlantic Salmon Trust, 1996)
    This paper summarises the results of an Atlantic salmon (Salmo salar) enhancement programme on the Delphi Fishery in the west of Ireland between 1991 and 1995. The aim of the programme was to increase salmon rod catches in the wake of a sea trout stock collapse. Smolts from two other Irish rivers, Burrishoole and Corrib, were released alongside Delphi fish and differentially tagged. Record angling catches were subsequently recorded. Catch rates varied from 0.6 to 12.7 per 1,000 smolts released. The comparative performance of the different stocks is assessed, with significant differences emerging between the stocks and between year classes In terms of survival/exploitation rates, run limes, sex ratios and homing patterns. The Delphi fish produced consistently lower overall returns than the Burrishoole groups, but consistently much higher numbers of early-running multi-sea-winter (MSW) salmon. These MSW salmon were predominantly female, while Delphi grilse were predominantly male. The Corrib fish performed relatively poorly. The smaller MSW salmon component of the non-indigenous groups ran later in the season than their Delphi counterparts. Important size differences in adult returns were noted and related to stock, sex, husbandry and selection by interceptory fisheries. It is suggested that the MSW salmon component of Delphi stocks is attributable to genetic factors, possibly linked to low freshwater temperature regimes. The programme has contributed to an increase in estuarine droll netting. Exploitation of grilse by all forms of coastal net ranged from 56% to 87%. Exploitation of MSW salmon by nets was lower, ranging from 0% to 54%, the lowest rates being achieved by the early-running Delphi MSW salmon. The programme is expensive and cannot be justified in terms of direct angling revenue. But when related accommodation income is taken into account, the financial results and the sustainment of the fishery's capital value broadly justify the programme to date.
  • 14th European Elasmobranch Association Conference Abstracts

    Irish Elasmobranch Group (Irish Elasmobranch Group, 2010)
    This publication presents the abstracts from a two day conference held in the Marine Institute, Oranmore, Galway. The conference was divided into six sessions focussing on the following topics: The Porbeagle Shark; Molecular Studies; Fisheries; Management and Conservation; Biology; and Tagging Studies. The keynote presentation was entitled “Threat and extinction risk in sharks, rays and chimaeras” and was delivered by Nicholas Dulvy.
  • Genetic variability in marine bivalvia: implications and applications in molluscan mariculture

    Wilkins, N P (Universa Press, 1976)
    The extent of genetic variability at enzyme gene loci is assessed in twelve species of marine bivalve molluscs of actual or potential commercial importance. Approximately one third of these loci are polymorphic, average heterozygosity is 0.14, and an average of 3.9 alleles are segregating per polymorphic locus. Hatchery-produced samples exhibit a lower proportion of polymorphic loci and a loss of some alleles at polymorphic loci. In two hatchery-produced families of Crassostrea gigas, phenotype frequencies at two loci depart from Mendelian expectations in young individuals. The implications of these hatchery induced alterations are discussed, together with some possible applications of biochemical genetics in molluscan mariculture.
  • Proceedings of the Fourth Irish Marine Biotoxin Science Workshop

    Marine Institute; Bord Iascaigh Mhara; Irish Shellfish Association; Food Safety Authority of Ireland (Marine Institute, 2003)
    The workshop is part of the Marine Institute’s role as the National Reference Laboratory for Marine Biotoxins in Ireland. This workshop is an annual event, where scientists, regulators and shellfish farmers meet to review developments in the monitoring and research of Biotoxins in Ireland and internationally. Our specific objectives for the 2003 Workshop are: (1) Review the Irish Biotoxin Monitoring system and to assess the trends in toxicity during 2003; (2) Summarise current Irish research work in Harmful Algal Blooms and Phytoplankton; (3) Focus on research work in Killary Harbour under the BOHAB project; (4) Take stock of developments and provide a forum for debate/feedback.
  • Proceedings of the Third Irish Marine Biotoxin Science Workshop

    Marine Institute; Bord Iascaigh Mhara; Food Safety Authority of Ireland (Marine Institute, 2002)
    The workshop is part of the Marine Institute’s role as the National Reference Laboratory for Marine Biotoxins in Ireland. This initiative was started in 2000 and was modelled on the Marine Science Biotoxin workshops, which have taken place in New Zealand since 1994. This workshop is an annual event, where scientists, regulators and shellfish farmers meet to review developments in the monitoring and research of Biotoxins in Ireland and internationally. The Institute’s roles are to Monitor/Research/Advise/Communicate. These are inextricably linked. It is essential to carry out targeted research in order to answer the questions which are generated by the monitoring. Objectives of the 2002 workshop: 1. To review the Irish Biotoxin Monitoring programme in 2002; 2. To summarise current and proposed new Irish research in the areas of Biotoxins and Harmful Algal Events (HAE’s); 3. To provide an International view on Biotoxins issues, with invited speakers from France, Norway and the UK; 4. To provide a forum for debate and communications.
  • Proceedings of the Second Irish Marine Biotoxin Science Workshop

    Marine Institute; Bord Iascaigh Mhara (Marine Institute, 2001)
    The Marine Institute’s objectives for Irish Biotoxin programme are to support the continued development of the Irish Shellfish Industry and to promote food safety, by building the best Biotoxin Management System in the Northern Hemisphere. The Marine Science Biotoxin Workshops are part of Marine Institute’s role as the National Reference Laboratory. The EU mandate for Reference Labs emphasises the need for dissemination of information. The objectives of the Marine Science Biotoxin Workshop are: (1) Take Stock of developments since last Workshop, April 2000; (2) Review Irish Monitoring System & Trends; (3) Summarise current Irish Research in HAE/Phytoplankton; (4) Compare with International Best Practice in New Zealand and USA; (5) Provide a Forum for Debate/Feedback
  • Proceedings of the 5th International Conference on Molluscan Shellfish Safety

    Marine Institute (Marine Institute, 2006)
    The aim of the global series of ICMSS Conferences has been well defined by our colleagues in Santiago de Compostela (Spain) who hosted the previous Conference in June 2002: “To establish a forum where useful, enriching debate and interchange of knowledge flow easily on a broad spectrum in the area of Shellfish Safety”. The ICMSS 04 Programme followed on the tradition and patterns which were set in Santiago de Compostela (2002); Southampton, New York, USA (2000) and in The Philippines (1998) of thematic sessions on a multi-disciplinary basis. Our session topics included: • Microbiological Status of Shellfish • Shellfish Viruses and Pathogens • Harmful Algal Blooms (HAB) and Biotoxin Contamination • HAB Mitigation and Depuration • Toxicology of Shellfish Toxins • Current and Emerging Analytical Methods • Quality Assurance and Consumer Safety • Regulation and Management of Shellfish Safety • Role of Industry in Risk Management and Innovation
  • Proceedings of the 2nd IWDG International Whale Conference. Muc Mhara Ireland's Smallest Whale

    Berrow, S D (ed); Deegan, B (ed) (Irish Whale and Dolphin Group, 2010)
    Muc Mhara – Ireland’s smallest whale. Proceedings of the 2nd Irish Whale and Dolphin Group International Whale Conference. Papers presented include, “Introduction: The harbour porpoise or Muc Mhara”, “An Irish name for the humble harbour porpoise”, “Life in the Fast Lane: Ecology and Behaviour of harbour porpoises in the Gulf of Maine”, “The ecology of harbour porpoise (Phocoena phocoena) in Irish waters: what strandings programmes tell us.”, “Passive acoustic monitoring of the harbour porpoise (Phocoena phocoena) in Irish waters”, “Abundance estimates of harbour porpoises in Irish waters”, “Satellite tracking of harbour porpoises in European Waters”, “Satellite tracking of harbour porpoises in European Waters”, “A cost of green energy: Are offshore renewables: a threat to porpoises?”, “Harbour porpoise populations and protection in an EU context”, “Assessment of Acoustic Deterrent Devices ‘Pingers’ and porpoise by catch rates in Irish Gillnet Fisheries in the Celtic Sea” and “Harbour porpoise Conservation in the Republic of Ireland”.