Now showing items 21-40 of 1296

    • Porcupine Bank Nephrops Grounds (FU16) 2019 UWTV Survey Report and catch scenarios for 2020

      Aristegui, M.; O’ Brien, S.; Tully, D.; Galligan, S.; McCorriston, P.; Bentley, K.; Lordan, C. (Marine Institute, 2019)
      This report provides the results of the seventh underwater television on the ‘Porcupine Bank Nephrops grounds’ ICES assessment area; Functional Unit 16. The survey was multi-disciplinary in nature collecting UWTV, CTD and other ecosystem data. In total 65 UWTV stations were successfully completed in a randomised 6 nautical mile isometric grid covering the full spatial extent of the stock. The mean burrow density observed in 2019, adjusted for edge effect, was 0.14 burrows/m². The final krigged abundance estimate was 1010 million burrows with a relative standard error of 5% and an estimated stock area of 7,130 km2. The 2019 abundance estimate was 9.5% lower than in 2018. Using the 2019 estimate of abundance and updated stock data implies catches between 2127 and 2637 tonnes in 2020 that correspond to the F ranges in the EU multi annual plan for Western Waters (assuming that all catch is landed). Four species of sea-pen; Virgularia mirabilis, Funiculina quadrangularis, Pennatula phosphorea and the deepwater sea-pen Kophobelemnon stelliferum were observed during the survey. Trawl marks were also observed on 31% of the stations surveyed.
    • The Labadie, Jones and Cockburn Banks Nephrops Grounds (FU20-21) 2019 UWTV Survey Report and catch scenarios for 2020.

      White, J.; Aristegui, M.; Blaszkowski, M.; Fee, D.; O'Connor, S.; Power, J.; Notaro, D. A.; O’ Brien, S.; Doyle, J. (Marine Institute, 2019)
      This report provides the main results of the 2019 underwater television survey on the ‘Labadie, Jones and Cockburn Banks’ ICES assessment area; Functional Unit 20-21. The 2019 survey was multi-disciplinary in nature collecting UWTV, and other ecosystem data. A total of 95 UWTV stations were completed at 6 nm intervals over a randomised isometric grid design. The mean burrow density was 0.06 burrows/m2 compared with 0.27 burrows/m2 in 2018. The 2019 geostatistical abundance estimate was 617 million, a 77% decrease on the abundance for 2018, with a CV of 5% which is well below the upper limit of 20% recommended by SGNEPS 2012. Low densities were observed throughout the ground. Using the 2019 estimate of abundance and updated stock data implies catch in 2020 that correspond to the F ranges in the EU multi annual plan for Western Waters are between 1131 and 1150 tonnes (assuming that discard rates and fishery selection patterns do not change from the average of 2016–2018). One species of sea-pen (Virgularia mirabilis) were recorded as present at the stations surveyed. Trawl marks were observed at 32% of the stations surveyed.
    • FU19 Nephrops grounds 2019 UWTV survey report and catch scenarios for 2020.

      Doyle, J.; Aristegui, M.; O’ Brien, S.; Lynch, D.; Vacherot, J.P.; Fitzgerald, R. (Marine Institute, 2019)
      This report provides the main results of the tenth underwater television survey of the various Nephrops patches in Functional Unit 19. The survey was multidisciplinary in nature collecting UWTV, multi-beam and other ecosystem data. In 2019 a total 44 UWTV stations were successfully completed. The mean density estimates varied considerably across the different patches. The 2019 raised abundance estimate was a 220% increase from the 2018 estimate and at 386 million burrows is below the MSY Btrigger (430 million). Using the 2019 estimate of abundance and updated stock data implies catch in 2020 that correspond to the F ranges in the EU multi annual plan for Western Waters are between 749 and 839 tonnes (assuming that discard rates and fishery selection patterns do not change from the average of 2016–2018). Two species of sea pen were observed; Virgularia mirabilis and Pennatula phosphorea which have been observed on previous surveys of FU19. Trawl marks were observed at 12 % of the stations surveyed.
    • The “Smalls” Nephrops Grounds (FU22) 2019 UWTV Survey Report and catch scenarios for 2020.

      Doyle, J.; O’ Brien, S.; Fitzgerald, R.; Vacherot, J.P.; Sugrue, S.; Quinn, M. (Marine Institute, 2019)
      This report provides the main results and findings of the fourteenth annual underwater television survey on the ‘Smalls grounds’ ICES assessment area; Functional Unit 22. The survey was multi-disciplinary in nature collecting UWTV, CTD and other ecosystem data. A total of 41 UWTV stations were surveyed successfully (high quality image data), carried out over an isometric grid at 4.5nmi or 8.3km intervals. The precision, with a CV of 9%, was well below the upper limit of 20% recommended by SGNEPS (ICES, 2012). The 2019 abundance estimate was 30% higher than in 2018 and at 1121 million is below the MSY Btrigger reference point (990 million). Using the 2019 estimate of abundance and updated stock data implies catch in 2020 that correspond to the F ranges in the EU multi annual plan for Western Waters are between 2247 and 2820 tonnes (assuming that discard rates and fishery selection patterns do not change from the average of 2016–2018). One species of sea pens were recorded as present at the stations surveyed: Virgularia mirabilis. Trawl marks were observed at 57% of the stations surveyed.
    • Aran, Galway Bay and Slyne Head Nephrops Grounds (FU17) 2019 UWTV Survey Report and catch scenarios for 2020.

      Aristegui, M.; Doyle, J.; O’ Brien, S.; Fitzgerald, R.; Vacherot, J.P.; Sugrue, S.; Quinn, M. (Marine Institute, 2019)
      This report provides the main results and findings of the seventeenth annual underwater television on the Aran, Galway Bay and Slyne head Nephrops grounds, ICES assessment area; Functional Unit 17. The survey was multi-disciplinary in nature collecting UWTV, CTD and other ecosystem data. In 2019 a total of 41 UWTV stations were successfully completed, 31 on the Aran Grounds, 5 on Galway Bay and 5 on Slyne Head patches. The mean burrow density observed in 2019, adjusted for edge effect, was medium at 0.38 burrows/m². The final krigged burrow abundance estimate for the Aran Grounds was 458 million burrows with a CV (relative standard error) of 4%. The final abundance estimate for Galway Bay was 23 million and for Slyne Head was 12 million, with CVs of 11% and 8% respectively. The total abundance estimates have fluctuated considerably over the time series. The 2019 combined abundance estimate (493 million burrows) is 11% lower than in 2018, and it is below the MSY Btrigger reference point (540 million burrows). Using the 2019 estimate of abundance and updated stock data implies catches between 696 and 800 tonnes in 2020 that correspond to the F ranges in the EU multi annual plan for Western Waters, assuming that discard rates and fishery selection patterns do not change from the average of 2016–2018. Virgularia mirabilis was the only sea-pen species observed on the UWTV footage. Trawl marks were present at 7% of the Aran stations surveyed.
    • Summary Report on 2018 Residue Monitoring of Irish Farmed Finfish & 2018 Border Inspection Post Fishery Product Testing undertaken at the Marine Institute

      Glynn, D.; McGovern, E.; Kelly, C.; Moffat, R.; Farragher, E. (Marine Institute, 2019)
      On behalf of the Department of Agriculture, Food and Marine (DAFM), the Marine Institute carries out monitoring of chemical residues in finfish for aquaculture sector. This monitoring is set out in the annual National Residue Control Plan, which is approved by the European Commission, and is an important component of the DAFM food safety controls and is implemented under a service contract with the Food Safety Authority of Ireland. Since 1999, the Marine Institute has implemented the National Residues Monitoring Programme for aquaculture. This is carried out on behalf of the Sea Fisheries Protection Authority, which is the responsible organisation for residue controls on farmed finfish. In 2018, in excess of 920 tests and a total of 2,611 measurements were carried out on 171 samples of farmed finfish for a range of residues. Implementation of the Aquaculture 2018 Plan involves taking samples at both farm and processing plant: • 123 target samples taken at harvest: 110 farmed salmon and 13 freshwater trout. • 48 target samples were taken at other stages of production: 40 salmon smolts and 8 freshwater trout. All 2018 samples were compliant. For target sampling of farmed fish, a summary table of the residue results from 2005 - 2018 is outlined in Table 1. Overall, the outcome for aquaculture remains one of consistently low occurrence of residues in farmed finfish, with no non-compliant target residues results for the period 2006-2014, 0.11% and 0.10% non-compliant target residues results in 2015 and 2016 respectively and no non-compliant target results in 2017 and 2018.
    • Cruise report: Irish Beam trawl Ecosystem Survey 2018

      Gerritsen, H.D.; Kelly, E.; O'Hea, B.; Ni Chonchuir, G. (Marine Institute, 2018)
      The third annual Irish Beam trawl Ecosystem (IBES) took place from 9-19th March 2018 on RV Celtic Explorer in the western Celtic sea. The main objective of IBES is to extend the geographic range of the CEFAS Q1 South-west Ecosystem Survey (Q1SWECOS), with the purpose of providing a swept-area biomass estimate for anglerfish (Lophius piscatorius and L. budegassa) in the Celtic Sea (ICES area VII). Secondary objectives are to collect data on the distribution and relative abundance of commercially exploited species as well as invertebrates and by-catch species, particularly vulnerable and indicator species. The survey also collects maturity and other biological information for commercial fish species in the western Celtic Sea. The IBES survey uses the same gear, methods and stratification as the Q1SWECOS. The IBES survey is formally coordinated by the ICES Working Group on Beam Trawl Surveys
    • Cruise report: Irish Anglerfish & Megrim Survey 2018

      Gerritsen, H.D.; Kelly, E.; Moore, S.J.; Stokes, D.; White, J. (Marine Institute, 2018)
      The 2018 Irish Anglerfish and Megrim Survey (IAMS) took place from 20th February to 19th March (area 7bcjk) and 10-21st April 2018 (area 6a) on RV Celtic Explorer. The main objective of the survey is to obtain biomass estimates for anglerfish (Lophius piscatorius and L. budegassa) and establish an abundance index for megrim (Lepidorhombus whiffiagonis and L. boscii) in areas 6a (south of 58°N) and 7 (west of 8°W). Secondary objectives are to collect data on the distribution and relative abundance of anglerfish, megrim and other commercially exploited species. The survey also collects maturity and other biological information for commercial fish species. The IAMS survey is coordinated with the Scottish Anglerfish and Megrim Survey (SIAMISS) and uses the same gear and fishing practices.
    • Surface Temperature Observations at Coninbeg Lightship on the South Coast of Ireland

      Farran, G. (Conseil International pour l'Exploration de la Mer (ICES), 1939)
    • Negotiations for the establishment of a pilchard fishery at Bantry in 1875

      Went, A. E. J. (Cork Historical and Archaeological Society, 1875)
    • The fat/water relationship in the mackerel Scomber scombrus L., pilchard, Sardina pilchardus (Walbaum) and sprat, Sprattus sprattus L., and the seasonal variation in fat content by size and maturity.

      Wallace, P. D.; Hulme, T. J. (Ministry of agriculture, fisheries and food Directorate of fisheries research., 1977)
      Mackerel, pilchard and sprat have the ability to store fat in their body tissues. During the spring and summer, when their main source of food, zooplankton, is abundant, fat reserves are accumulated. These reserves are utilized in the autumn and winter when zooplankton are scarce. Consequently, wide variations in fat content occur throughout a single year of life of these species. This report describes the relationship that exists between fat and water in these species and describes how the fat content varies with size, maturity stage and season.
    • Herring larval surveys in the Celtic Sea and division VIIj in 1982/83

      Grainger, R. J.; Barnwall, E.; Cullen, A. (International Council for the Exploration of the Sea, 1983)
      Surveys for herring larvae in the Celtic Sea were conducted between October 1982 ~ and February 1983 for the fifth successive season. To take account of the amalgamation of the Celtic Sea and Div VIIJ herring for assessment purposes and to ascertain if many larval drift into the Irish Sea, the survey grid of previous years was modified for the 1982/83 season. However, because of the nature of the larvae distribution it appears reasonable to compare the larvae index for 1982/83 with those of the previous seasons. The increase in indices since 1978/79 has continued up to 1982/83 indicating a steady, but slow, recovery of the spawning stock. Very few larvae appear to drift into the Irish Sea.
    • Biosensors for the monitoring of harmful algal blooms

      McPartlin, D. A.; Loftus, J. H.; Crawley, A. S.; Silke, J.; Murphy, C. S.; O’Kennedy, R. J. (Elsevier, 2017)
      Harmful algal blooms (HABs) are a major global concern due to their propensity to cause environmental damage, healthcare issues and economic losses. In particular, the presence of toxic phytoplankton is a cause for concern. Current HAB monitoring programs often involve laborious laboratory-based analysis at a high cost and with long turnaround times. The latter also hampers the potential to develop accurate and reliable models that can predict HAB occurrence. However, a promising solution for this issue may be in the form of remotely deployed biosensors, which can rapidly and continuously measure algal and toxin levels at the point-of-need (PON), at a low cost. This review summarises the issues HABs present, how they are difficult to monitor and recently developed biosensors that may improve HAB-monitoring challenges.
    • Gbm.auto: A software tool to simplify spatial modelling and Marine Protected Area planning

      Dedman, Simon; Officer, Rick; Clarke, Maurice; Reid, David G.; Brophy, Deirdre (Public Library of Science (PLoS), 2017)
      Boosted Regression Trees. Excellent for data-poor spatial management but hard to use Marine resource managers and scientists often advocate spatial approaches to manage data-poor species. Existing spatial prediction and management techniques are either insufficiently robust, struggle with sparse input data, or make suboptimal use of multiple explanatory variables. Boosted Regression Trees feature excellent performance and are well suited to modelling the distribution of data-limited species, but are extremely complicated and time-consuming to learn and use, hindering access for a wide potential user base and therefore limiting uptake and usage. BRTs automated and simplified for accessible general use with rich feature set We have built a software suite in R which integrates pre-existing functions with new tailor-made functions to automate the processing and predictive mapping of species abundance data: by automating and greatly simplifying Boosted Regression Tree spatial modelling, the gbm.auto R package suite makes this powerful statistical modelling technique more accessible to potential users in the ecological and modelling communities. The package and its documentation allow the user to generate maps of predicted abundance, visualise the representativeness of those abundance maps and to plot the relative influence of explanatory variables and their relationship to the response variables. Databases of the processed model objects and a report explaining all the steps taken within the model are also generated. The package includes a previously unavailable Decision Support Tool which combines estimated escapement biomass (the percentage of an exploited population which must be retained each year to conserve it) with the predicted abundance maps to generate maps showing the location and size of habitat that should be protected to conserve the target stocks (candidate MPAs), based on stakeholder priorities, such as the minimisation of fishing effort displacement. Gbm.auto for management in various settings By bridging the gap between advanced statistical methods for species distribution modelling and conservation science, management and policy, these tools can allow improved spatial abundance predictions, and therefore better management, decision-making, and conservation. Although this package was built to support spatial management of a data-limited marine elasmobranch fishery, it should be equally applicable to spatial abundance modelling, area protection, and stakeholder engagement in various scenarios.
    • Evaluation of Non-destructive Molecular Diagnostics for the Detection of Neoparamoeba perurans

      Downes, Jamie K.; Rigby, Megan L.; Taylor, Richard S.; Maynard, Ben T.; MacCarthy, Eugene; O'Connor, Ian; Marcos-Lopez, Mar; Rodger, Hamish D.; Collins, Evelyn; Ruane, Neil M.; et al. (Frontiers Media SA, 2017)
      Amoebic gill disease (AGD) caused by Neoparamoeba perurans, has emerged in Europe as a significant problem for the Atlantic salmon farming industry. Gross gill score is the most widely used and practical method for determining AGD severity on farms and informing management decisions on disease mitigation strategies. As molecular diagnosis of AGD remains a high priority for much of the international salmon farming industry, there is a need to evaluate the suitability of currently available molecular assays in conjunction with the most appropriate non-destructive sampling methodology. The aims of this study were to assess a non-destructive sampling methodology (gill swabs) and to compare a range of currently available real-time polymerase chain-reaction (PCR) assays for the detection of N. perurans. Furthermore a comparison of the non-destructive molecular diagnostics with traditional screening methods of gill scoring and histopathology was also undertaken. The study found that all molecular protocols assessed performed well in cases of clinical AGD with high gill scores. A TaqMan based assay (protocol 1) was the optimal assay based on a range of parameters including % positive samples from a field trial performed on fish with gill scores ranging from 0 to 5. A higher proportion of gill swab samples tested positive by all protocols than gill filament biopsies and there was a strong correlation between gill swabs tested by protocol 1 and gross gill score and histology scores. Screening for N. perurans using protocol 1 in conjunction with non-destructive gill swab samples was shown to give the best results.
    • The GOSHIP A02 Survey 2017 Taking the Pulse and Temperature of the North Atlantic Ocean.

      McGovern, E.; Cusack, C.; Wallace, D.; Croot, P. (The Journal of Ocean Technology, 2017)
    • Fisher's preferences and trade-offs between management options

      Fitzpatrick, Mike; Maravelias, Christos D; Eigaard, Ole Ritzau; Hynes, Stephen; Reid, David (Wiley, 2017)
      Failure to understand the potential responses of fishers to management measures creates a significant risk of revisiting the familiar scenario of perverse and unintended consequences of those measures. This paper reports on a choice experiment survey to evaluate fisher's preferences for various management measures proposed under the EU Common Fisheries Policy (CFP) reform process, but the conclusions have wider relevance as similar measures are used by comparable fleets in fisheries globally. The survey was conducted with fishers involved in mixed pelagic and demersal fisheries in Ireland, pelagic fisheries in Denmark and demersal fisheries in Greece. Fisheries management policies were characterized by five attributes designed both to cover the principal CFP reform proposals and to integrate ecological, social, economic and institutional factors affecting fisher's decisions. The study uses a random utility modelling framework to reveal the preferences of the fishers across the alternative policy attributes. Results show that while there are generally preferences both for healthy stocks and for maintaining the importance of fishing to the local community, strong interfishery preference differences exist. These differences are most notable in relation to a discard ban and to the use of individual transferable fishing rights, favoured in Denmark, but not in Ireland for instance. The strength of these interfishery differences supports the assertion that there are no panaceas in fisheries management and that solutions should be tailored within the context of specific fisheries. Not doing so could create a significant risk of inappropriately managed fisheries that may lead to unsustainable outcomes.
    • Decreased Performance of Rainbow Trout Oncorhynchus mykiss Emergence Behaviors Following Embryonic Exposure to Benzo[a]pyrene

      Ostrander, G.K.; Anderson, J.J. (United States Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service, 1990)
      The sublethal effects induced by a model carcinogen and environmental contaminant on salmonid emergence behaviors have been studied. Rainbow trout embryos were exposed for 24 hours to 25 IAg/mL of benzo[a)pyrene 1 week prior to hatching. Exposures occurred during the late organogenesis period of development and allowed assessment of how a single embryonic exposure might affect emergence behaviors nearly 6 weeks later. Though no differences in numbers of alevins successfully emerging were observed, a significant decrease was noted in performance of the upstream orientation behaviors characteristic ofemergence among wild individuals.These findings are discussed in terms ofa model describing the role of upstream swimming behavior after emergence.
    • Evidence for long-term change in length, mass and migration phenology of anadromous spawners in French Atlantic salmon Salmo salar

      Bal, G.; Montorio, L.; Rivot, E.; Prévost, E.; Baglinière, J.-L.; Nevoux, M. (Wiley, 2017)
      This study provides new data on Atlantic salmon Salmo salar life‐history traits across France. Using a long‐term recreational angling database (1987–2013) covering 34 rivers in three regions (genetic units), a decline in individual length, mass and a delayed adult return to French rivers was reported. Temporal similarities in trait variations between regions may be attributed to common change in environmental conditions at sea. The relative rate of change in phenotypic traits was more pronounced in early maturing fish [1 sea‐winter (1SW) fish] than in late maturing fish (2SW fish). Such contrasted response within populations highlights the need to account for the diversity in life histories when exploring mechanisms of phenotypic change in S. salar. Such detailed life‐history data on returning S. salar have not previously been reported from France. This study on French populations also contributes to reducing the gap in knowledge by providing further empirical evidence of a global pattern in S. salar across its distribution range. Results are consistent with the hypothesis that the observed changes in life‐history traits are primarily associated with environmental changes in the North Atlantic Ocean. They also emphasize the presence of less important, but still significant contrasts between region and life history.
    • A field deployable method for a rapid screening analysis of inorganic arsenic in seaweed.

      Bralatei, Edi; Nekrosiute, Karolina; Ronan, Jenny; Raab, Andrea; McGovern, Evin; Stengel, Dagmar B.; Krupp, Eva M.; Feldmann, Joerg (Springer Nature, 2017)
      Inorganic arsenic (iAs) in 13 store-bought edible seaweed samples and 34 dried kelp (Laminaria digitata) samples was determined by a newly developed, field-deployable method (FDM) with the aid of a field test kit for arsenic in water. Results from the FDM were compared to results from speciation analysis achieved by using high performance liquid chromatography coupled to inductively coupled plasma mass spectrometry (HPLC-ICP-MS). The FDM consisted of a simple extraction method using diluted HNO3 to quantitatively extract iAs without decomposing the organoarsenicals to iAs followed by the selective volatilisation of iAs as arsine (AsH3) and subsequent chemo-trapping on a filter paper soaked in mercury bromide (HgBr2) solution. Method optimization with a sub-set of samples showed 80–94% iAs recovery with the FDM with no matrix effect from organo-arsenic species in the form of dimethylarsinic acid (DMA) on the iAs concentration. The method displayed good reproducibility with an average error of ±19% and validation by HPLC-ICP-MS showed that the results from the FDM were comparable (slope = 1.03, R2 = 0.70) to those from speciation analysis with no bias. The FDM can be conducted within an hour and the observed limit of quantification was around 0.05 mg kg−1 (dry weight). This method is well suited for on-site monitoring of iAs in seaweed before it is harvested and can thus be recommended for use as a screening method for iAs in seaweed.