• An Assessment of Water Quality Data from Kilkieran Bay, Co. Galway

      O'Donohoe, G; Hensey, M; O'Connor, B (Marine Institute, 2000)
      A programme monitoring water quality was carried out at 11 sites in Kilkieran Bay, Co. Galway from 1984 to the 1998, for the most part. Continuous monthly readings were recorded at 5 of these sites. Three sites were sampled for temperature, salinity, nitrate, nitrite and phosphate. Three replicate samples were taken at each sampling event. While salinity remained relatively stable throughout, temperature varied considerably between winter and summer months (e.g. Lettercallow, 3.5-18.5ºC), at each of the sites. Nutrient levels were highest in winter months at all sites. The innermost sites tended to have lower salinities and lower nutrient levels. However, there were no statistical differences in nutrient levels among the sites and from year to year. These findings suggest that there was no appreciable increase (or decrease) in nutrient loading within Kilkieran Bay. It is recommended that sampling within the bay is defined according to the broad geographic regions outlined and that intensive sampling was not necessary.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters, 1997-1999

      McGovern, E; Rowe, A; McHugh, B; Costello, J; Bloxham, M; Duffy, C; Nixon, E (Marine Institute, 2001)
      In accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs, the Marine Institute collected water and shellfish samples from major shellfish growing areas and analysed for physicochemical parameters, trace metal levels and chlorinated hydrocarbon concentrations. Since, with the exception of mercury, there are no currently applicable European standards for the concentration of these contaminants in shellfish, the levels were compared with the available standards and guidance values for human consumption, as compiled by the Oslo and Paris Commission (OSPAR) countries. As in previous years, the water quality from shellfish growing areas was good and conformed to the guidelines and requirements of the Directive. Petroleum hydrocarbons were not observed in any of the shellfish waters or as deposits on the shellfish. Chlorinated hydrocarbon levels were very low, evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. Trace metal levels were consistently low with the exception of cadmium in oyster tissue, which was slightly elevated in the 1999 samples from Clew Bay, Inner Tralee Bay, Aughinish Limerick and Kilkieran. However these levels did not exceed the Dutch human consumption standard value or the EU maximum limit of 1.0 mg/kg wet weight due to apply from 2002. This survey confirms previous studies which show Irish shellfish products are effectively free from trace metal and chlorinated hydrocarbon contamination.
    • The fate of oxytetracycline in the marine environment of a salmon cage farm

      Coyne, R; Smith, P; Moriarty, C (Marine Institute, 2001)
      This paper gives a summary of previously published results of studies on the dispersal of oxytetracycline from the vicinity of a typical salmon farm. These studies showed the environmental impact of occasional treatments to be negligible. Concentrations of oxytetracycline (OTC) were measured in the benthic sediments and in mussel Mytilus edulis sampled in the vicinity of an inshore salmon farm on the west coast of Ireland. Concentrations between 1.0 μg/g and 14.7 μg/g were observed in sediments within 120 m from the farm. Concentrations declined exponentially with time, reaching low levels after 32 days and reduced to traces at 66 days. The highest concentrations were observed in the top 2 cm of sediment, falling to trace levels at a depth of 10 cm. The half-life of OTC persistence in mussels was found to be approximately 2 days. Residues in unpolluted sediment beneath the cages were never present in high concentrations and were flushed out rapidly. In the presence of excessive quantities of unconsumed food pellets on the seabed and in anoxic sediment, the persistence of OTC was significantly prolonged. Monitoring the quality of the sediment could therefore provide adequate indication of any risk of accumulation of antibiotic, without the need for elaborate chemical analyses. Residues in sediment, invertebrates and salmon could account for not more than 1.3% of total input of OTC. It was concluded that the antibiotic was very rapidly dispersed in the environment and its use in salmon therapy posed no material risk to human or environmental health.
    • Winter Nutrient Monitoring of the Western Irish Sea – 1990 to 2000

      McGovern, E; Monaghan, E; Bloxham, M; Rowe, A; Duffy, C; Quinn, A; McHugh, B; McMahon, T; Smyth, M; Naughton, M; McManus, M; Nixon, E (Marine Institute, 2002)
      Winter nutrient concentrations in the western Irish Sea have been monitored annually from 1990 to 2000. Surface samples have been taken between Dundalk Bay and Carnsore Point and analysed for total oxidised nitrogen (TOxN), ortho-phosphate (ortho-P), silicate and salinity. More recently monitoring has been extended into the Celtic Sea. Data from this monitoring programme are presented in detail, along with comparisons to existing data sets. The spatial distribution of nutrients and salinity are presented for each year in contour or classed plots (depending on sample coverage for the particular year). Salinity values were representative of those expected in the Irish Sea and TOxN, ortho-P and silicate values were in general agreement with previous studies. A short summary of studies on nutrient levels in estuaries on the western Irish Sea is presented. In addition, riverine input data supplied by the Environmental Protection Agency (EPA) is used to evaluate the relative magnitude of nutrient inputs from riverine and oceanic sources. Nutrient concentrations are considered using an ecological quality objectives (EcoQOs) approach, proposed as part of the Oslo Paris Convention’s (OSPAR) ‘Common Procedure for Identification of the Eutrophication Status of the Maritime Area’, in partial consideration of the trophic status of the western Irish Sea. Although there is evidence for nutrient enrichment in some estuarine waters and possibly to a lesser extent in some coastal waters, there is little evidence for generally elevated nutrient levels in coastal and offshore waters in the western Irish Sea. Salinity regression curves were calculated for TOxN and ortho-P values in order to generate salinity-normalised concentrations for trend determinations. Regression and trend analysis were carried out on the sample area as a whole and also on regions defining the north, mid, and south western Irish Sea. Trend analysis has been performed, based on nutrient-salinity regressions, using Trend-Y-Tector. A decrease in TOxN over the study period (ranging from 4 to13%) is observed in all regions analysed with the exception of the south west Irish Sea, where a 5% increase was indicated. Analysis of trends in ortho-P concentration showing decreasing trends ranging from 20 to 33%. On visual examination, trends in TOxN are not as intuitively apparent as trends in ortho-P concentrations, therefore it may not be prudent to draw conclusions from them at this stage. Trend analysis of riverine inputs shows an increase in TOxN by 17% and no apparent trend in ortho-P levels. These trends are not consistent with trends observed in the Irish Sea. On the basis of this assessment, it is recommended that this monitoring be continued. The design of future nutrient monitoring surveys is considered, with a view to improving the efficacy of the monitoring regime.
    • Monitoring of zebra mussels in the Shannon-Boyle navigation, other

      Minchin, D; Lucy, F; Sullivan, M (Marine Institute, 2002)
      The zebra mussel (Dreissena polymorpha) population has been closely monitored in Ireland following its discovery in 1997. The species has spread from lower Lough Derg, where it was first introduced, to most of the navigable areas of the Shannon and other interconnected navigable waters. This study took place in the summers of 2000 and 2001 and investigated the relative abundance and biomass of zebra mussels found in the main navigations of the Shannon and elsewhere in rivers, canals and lakes where colonisation was likely. During 2000 zebra mussels were found for the first time in Carnadoe, Kilglas and Grange Loughs on the River Shannon. In 2001, they were discovered on the Ballinasloe Navigation at Poulboy Lough and in Ballinasloe Harbour. For the first time outside of the Shannon-Boyle navigation, established populations were discovered in Garadice Lough on the Shannon-Erne Waterway and in Ringsend Basin and Tullamore Harbour on the Grand Canal. Zebra mussels continue to have their greatest densities in lakes and large reservoirs of the Shannon-Boyle navigation. A maximum biomass of 4.1kg per sq.m was recorded in Lough Key. No zebra mussel larvae or their attached stages were found in the larger lakes outside of the Shannon-Boyle and Erne Navigations. Larvae were found however, in Tullamore Harbour for the first time. In separate studies approximately two hundred adults were found in Lough Bo, Co. Sligo and less than ten specimens were found in Lough Gill, Co. Sligo. The only living population of native freshwater mussels (Anodonta spp.) presently known in the lake regions of the Shannon is in the Carnadoe Cut, between Carnadoe Lough and Kilglas Lough. This population of Anodonta spp. is fouled with zebra mussels. Freshwater mussels were also found in Garadice Lough and Assaroe Reservoir. These were also fouled with zebra mussels.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters, 2000

      Glynn, D; Tyrrell, L; McHugh, B; Rowe, A; Costello, J; McGovern, E (Marine Institute, 2003)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water, trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. EU Commission Regulation 466/2001/EC (as amended by Regulation 221/2002/EC) came into effect on 5th April 2002. This set maximum levels for mercury, cadmium and lead in bivalve molluscs of 0.5mg/kg, 1mg/kg, and 1.5mg/kg wet weight respectively. In the absence of EU standards for other contaminants in shellfish, monitoring results have been compared to strictest guidance or standard values available in other OSPAR Convention contracting countries. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. Levels of chlorinated hydrocarbons and trace metals in shellfish tissue were very low in all areas, which is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. This survey confirms previous studies (McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish products.
    • The Irish Coral Task Force and Atlantic Coral Ecosystem Study: Report on Two Deep-Water Coral Conservation Stakeholder Workshops Held in Galway in 2000 and 2002

      Grehan, A; Long, R; Deegan, B; Ó Cinneide, M (Marine Institute, 2003)
      Increasing public and media awareness of the unique nature of European deep-water corals has put the focus firmly on the need for sustainable management of European offshore living resources. The well documented destruction of deep-water corals off Norway and potentially along the entire European margin combined with extremely slow coral habitat recovery rates, has created a sense of urgency to move towards implementation of the appropriate management measures to ensure the long-term survival of this spectacular and important habitat. In the process, deep-water coral conservation has become in many ways a paradigm for a shift away from traditional sectoral driven resource management approaches, towards an inclusive integrated ecosystem approach to the management of European offshore resources. The EU Fifth Framework Programme, in an effort to increase the socio-economic impact of its R&D projects strongly encouraged the formation of scientist-stakeholder partnerships and development of a suitable research-product delivery mechanism. The major (€2.1 million) European Union funded research project: the Atlantic Coral Ecosystem Study successfully responded to these new challenges in a number of innovative ways. In particular, the establishment of an ACES project-stakeholder partnership through consultative workshops, provided a means for stakeholders to prioritise the scientific research and created a forum for rapid dissemination of scientific results. Complementary initiatives arising from these meetings, such as the formation of the ad hoc Irish Coral Task Force, provided a mechanism whereby scientific findings could be translated into policy advice for the appropriate national authorities. This report serves as a record of the consultative process undertaken during two stakeholder workshops held in Galway on 23rd June 2000 and 24th June 2002. Section A contains conclusions and summary records of the two meetings. Section B contains a series of papers presented at the workshops to provide detailed information on: cold-water coral research and conservation initiatives; fishing related issues; oil and gas related issues and conservation legislation and legal issues. The 2000 meeting was sponsored by the Atlantic Coral Ecosystem Study, while the 2002 meeting was sponsored by the Marine Institute (Ireland), as part of its support for the Irish Coral Task Force and ACES. Between the first and the second meeting, the need for scientific advice to support the designation of Special Areas of Conservation to protect corals under the EU Habitats Directive became a clear priority. Finally, it is obvious that much work remains to be done to achieve effective protection of deep-water corals and similarly threatened 'hot spots' of marine biodiversity along the European shelf and slope. It is also clear, however, that successful implementation of conservation measures will require on-going dialogue with stakeholders, and their participation in the decision making process.
    • An Epidemiological Investigation of the Re-Emergence of Pancreas Disease in Irish Farmed Atlantic Salmon (Salmo salar L.) in 2002

      McLoughlin, M F; Peeler, E; Foyle, K L; O'Ceallachain, D; Geoghegan, F (Marine Institute, 2003)
      In the early 1990’s pancreas disease (PD) was shown to be the most significant cause of mortality in Irish farmed salmon (Wheatley et al., 1995, Menzies et al., 1996, Crockford et al., 1999). At that time the aetiology of PD was uncertain but in 1995 it was conclusively shown that PD was caused by a virus subsequently named salmon pancreas disease virus (SPDV), (Nelson et al., 1995, McLoughlin et al., 1996). It has since been further classified and named salmonid alphavirus (Weston et al., 1999, Weston et al., 2002). The clinical and histopathological features of naturally occurring pancreas disease in farmed Atlantic salmon in Ireland were described by Murphy et al., 1992 and McLoughlin et al., 2002. The original epidemiological studies of PD in Ireland indicated that mortality rates up to 48% have occurred in farmed Atlantic salmon in their first year in the sea on some individual fish farms (Menzies et al., 1996). PD was recorded in over 70% of marine sites monitored and the majority of PD outbreaks occurred during August to October (Crockford et al., 1999). A serological survey for the presence of SPDV antibody in 1996 revealed 53% of the sites (9/17) were positive and that not all positive sites had recognised clinical signs of PD. This indicated a relatively low incidence and severity of PD at that time (McLoughlin et al., 1998). This pattern persisted until 2002 when there was a serious increase in both the incidence and severity of PD reported on farmed Atlantic salmon marine sites in Ireland. In order to identify factors associated with this re-emergence of PD in Irish farmed salmon, an in-depth epidemiological investigation was carried out on all marine sites. In trying to identify the cause of a disease from epidemiological studies the concept of time, place and individual is paramount, i.e. why did a particular disease occur in a particular animal or group of animals at a particular time in a particular place? Epidemiological study designs are chosen so that predictor variables are measured in affected and non-affected “units”. These “units” may be cells, animals, pens, farms or countries. The association between these predictor variables and disease is then examined. Where associations are demonstrated then risk factors for disease can be identified. A risk factor is a predictor variable associated with the disease. However the identification of a risk factor does not imply causation. The strength, consistency, temporality and dose response effect of the risk factor add weight to it being causal but only an intervention study where the risk factor is added or omitted can confirm this. Individual or univariate analysis of the relationship between a predictor variable and disease may result in an association being demonstrated. However it is dangerous to read too much into univariate analyses as factors which have been ignored, not measured or not seen as important may have a confounding effect. Multivariate analysis is used to try to provide estimates of association adjusted for the effect of confounding factors is a much more accurate and powerful epidemiological tool, but was of limited application in this snapshot survey of a single production cycle. This report aims to describe the occurrence and severity of PD in Irish farmed salmon in 2002-2003 and to identify risk factors associated with the re-emergence of severe PD. Finally, recommendations are made on how PD can be managed to reduce its serious impact on the health, welfare and productivity of Irish farmed salmon.
    • The Occurrence and Risk Assessment of the Pesticide Toxaphene in Fish from Irish Waters

      McHugh, B; Glynn, D; Nixon, E; McGovern, E (Marine Institute, 2003)
      The European Union project “Investigation into the monitoring, analysis and toxicity of toxaphene” (MATT), involving participants from The Netherlands, Ireland, Norway and Germany, began in 1997. Analytical methodology, concentration information and statistical interpretation of results for three indicator congeners, CHB’s 26, 50 and 62, are presented. Data from 55 samples, covering 18 different fish species, from Irish waters are documented. Concentrations were lowest in shellfish and in fish species having low lipid content and were highest in medium/high lipid species. Males from a number of fish species were shown to contain significantly higher concentrations than observed in female fish. Overall no samples were shown to exceed existing German MRL or Canadian TDI recommendations.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 2001

      Tyrrell, L; Glynn, D; McHugh, B; Rowe, A; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2003)
      The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2001, a total of 44 samples from 20 different species of finfish were collected from six major Irish fishing ports and analysed for total mercury concentration in the edible tissue. The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.42 mg/kg wet weight with a mean and median of 0.09 and 0.07 mg/kg respectively. These levels are within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EC (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively, set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters 2001

      Glynn, D; Tyrrell, L; McHugh, B; Rowe, A; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2003)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water, trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2001, a total of 23 samples from 20 different shellfish sites were analysed for trace metals and chlorinated hydrocarbons. The median concentration of mercury in shellfish sampled in 2001 was <0.03 mg/kg wet weight, with a maximum of 0.04 mg/kg wet weight which is well within the maximum limit of 0.50 mg/kg wet weight for mercury in bivalve molluscs set by the EU. The levels of lead and cadmium detected were low, with means of 0.20 and 0.24 mg/kg wet weight and maxima of 0.37 and 0.74 mg/kg wet weight respectively, also within the respective maximum levels of 1.50 and 1 mg/kg wet weight set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in shellfish. However these results were compared with the strictest standard or guidance values for shellfish, which are applied by contracting countries to OSPAR, and were found to be well below the strictest values listed. This is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2003; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish aquaculture.
    • Environmental Quality and Carrying Capacity for Aquaculture in Mulroy Bay, Co. Donegal

      Telfor, T; Robinson, K (Marine Institute, 2003)
      Concerns over recent expansion of the aquaculture sectors in Mulroy Bay have lead to several investigations on environmental quality within the area, including a recent report (in 2000) for the Irish Marine Institute by the Centre for Marine Resources and Mariculture (C-Mar, 2000). This study reported on changes in the physical and chemical environment within Muloy Bay over a two year data collection period, and from data collected by Marine Harvest Ireland, and related observed changes to aquaculture (notably salmon farming) outputs. The study also involved sediment bioassays using sediment collected in Mulroy Bay and a variety of test organisms to investigate whether any toxicants were present that may affect the benthic community. The current study was commissioned by the Marine Institute to draw together the results of long term monitoring of water and sediment quality, and hydrography, within Mulroy Bay collected by the Institute of Aquaculture (IoA), Stirling, on behalf of Marine Harvest Ireland since 1986. The study examines trends in the physical and chemical environment within Mulroy Bay (predominantly using IoA data) since recording began, and relates results to the present activities within the bay. The aims of the study are: • to produce a carrying capacity model for Mulroy Bay as a whole • to produce maps of waste dispersion from fish cage sites • to assess the environmental sustainability of current aquaculture activities in Mulroy Bay
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 1997-2000

      Tyrrell, L; Glynn, D; Rowe, A; McHugh, B; Costello, J; Duffy, C; Quinn, A; Naughton, M; Bloxham, M; Nixon, E; McGovern, E (Marine Institute, 2003)
      The Marine Institute samples a range of finfish species landed at five major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 1997 – 2000, a total of 112 samples from 23 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible. The concentration of mercury ranged from 0.03 to 0.18 mg/kg wet weight in 1997, <0.03 to 0.19 mg/kg wet weight in 1998, <0.03 to 0.29 mg/kg wet weight in 1999 and 0.03 to 0.33 mg/kg wet weight in 2000. These levels are well within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EC. This survey confirms previous studies, which show that Irish seafoods are effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively, set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting parties to OSPAR. The levels of these additional contaminants are well below the strictest values listed.
    • Monitoring of Tributyl Tin Contamination in Six Marine Inlets using Biological Indicators

      Minchin, D (Marine Institute, 2003)
      Dogwhelk and periwinkle specimens were collected from six bays/estuaries in 2000, where Tributyl Tin (TBT) contamination was suspected. In four estuaries, shells of dead Pacific oysters were collected from 7 sites in the vicinity of culture installations. Observations on imposex in dogwhelks, intersex in periwinkles and shell thickness in the Pacific oysters were used to assess the degree of TBT contamination. The results showed low levels of contamination, which are unlikely to have detrimental effects to mollusc culture or fisheries in Mulroy Bay, Valentia Harbour or Tralee Bay. Thickening of oyster shells was detected in Carlingford Lough, Waterford Harbour, Cork Harbour and Fountainstown. The small degree of thickening was considered unlikely to affect marketability.
    • Salmon Mortalities at Inver Bay and McSwyne’s Bay Finfish farms, County Donegal, Ireland, during 2003

      Cronin, M.; Cusack, C.; Geoghegan, F.; Jackson, D.; McGovern, E.; McMahon, T.; O'Beirn, F.X.; Ó Cinneide, M.; Silke, J. (Marine Institute, 2004)
      This report details the investigations into a major mortality of farmed salmon at Inver Bay and McSwyne’s Bay, Co. Donegal in July 2003. Previous reports were provided on 29th July 2003 and on 11th August 2003. The information is based upon analysis and research by MI scientists, a review of environmental data, survey reports by external consultants, inputs from veterinary practitioners who visited the site, reports from DCMNR staff in Killybegs, and site visits made by DCMNR / MI inspectors. Following a review meeting of the principal investigators on the 9th October, 2003, MI proceeded to carry out further scientific investigations. DCMNR also commissioned Kirk McClure Morton Consulting Engineers (KMM) to carry out a parallel investigation of the mortalities at Inver Bay and McSwynes Bay salmon farms. MI provided support as required to the KMM study, the report for which was furnished to DCMNR and MI on 11 February 2004. (KMM, 2004) MI wishes to acknowledge the high level of co-operation and assistance that it received from the owners and staff of Creevin Fish Farm Ltd, Eany Fish Products Ltd and Ocean Farms Ltd. It also wishes to acknowledge the assistance of veterinary practitioners, DCMNR staff and others in the course of this investigation.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters 2002

      Glynn, D; Tyrrell, L; McHugh, B; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2004)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water and trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2002, a total of 24 samples from 22 different shellfish sites were analysed for chlorinated hydrocarbons and trace metals, including nickel and silver. The median concentration of mercury in shellfish sampled in 2002 was <0.03 mg/kg wet weight, which is well within the European maximum limit of 0.50 mg/kg wet weight for mercury in bivalve molluscs. The levels of lead and cadmium detected were low, with means of 0.16 and 0.33mg/kg wet weight and maxima of 0.34 and 0.66 mg/kg wet weight respectively, also within the respective European maximum levels of 1.50 and 1 mg/kg wet weight. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in shellfish. Therefore, these results were compared with the strictest standard or guidance values for shellfish, which are applied by contracting countries to the OSPAR Convention, and were found to be well below the strictest values listed. This is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2003a, 2003b; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish aquaculture.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 2002

      Tyrrell, L; Twomey, M; Glynn, D; McHugh, B; Joyce, E; Costello, J; McGovern, E (Marine Institute, 2004)
      The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2002, a total of 38 samples from 20 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible tissue (Common names and species names are listed in Appendix 3). The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.46 mg/kg wet weight with a mean and median of 0.09 and 0.06 mg/kg respectively. These levels are within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EU (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively, set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standards or guidance values for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed.
    • Review of the Potential Mechanisation of Kelp Harvesting in Ireland

      Werner, A; Kraan, S (Marine Institute, 2004)
      A diverse seaweed industry has developed in Ireland over the past few decades. The seaweed industry today comprises several sectors, such as biopolymers, agriculture/horticulture, cosmetics, thalassotherapy and human consumption, with the former two sectors being of most economic importance. Approximately sixteen seaweed species are commercially utilised, three of which are of particular commercial importance. These are the calcified red algae, referred to as maërl, which mainly comprises of two species (Phymatolithon calcareum and Lithothamnion corallioides) and are exploited by a single company for agricultural, horticultural, food and cosmetic applications. The other bulk species is the brown alga Ascophyllum nodosum, which is used for alginate extraction and agriculture/horticulture applications. The latter species sustains an industry, which is an important factor in contributing to the maintenance of coastal communities especially in rural areas of the west coast, particularly in the Gaeltacht of Connemara (Guiry 1997, National Seaweed Forum, 2000). Mechanical harvesting of seaweeds in Ireland is limited to the exploitation of maërl. At present, one company has a licence to harvest calcified algae in the south-west of Ireland (Bantry Bay) with 8,000 - 10,000 wet tonnes of maërl being extracted from the seabed annually in recent years. The supply of raw material for the Ascophyllum-processing industry as well as for the other industrial sectors relies on harvesters who harvest the seaweed by hand. Although hand-harvesting provides a source of employment in rural areas along the west coast, the age profile is increasing and the numbers of harvesters are declining due to insufficient recruitment of younger harvesters (National Seaweed Forum 2000; Kelly et al. 2001). With growing demands for seaweeds, it is uncertain whether hand-harvesting will provide sufficient raw material in the long-term. The National Seaweed Forum has evaluated the current state of the Irish Seaweed Industry. The forum was launched by the Minister for Marine and Natural Resources in 1999 and consists of 19 members from state agencies, third-level institutions and industry. In the final report (National Seaweed Forum, 2000) it was stated that the natural sustainable seaweed resources in Ireland are under-utilised and the industrial potential, including high-value applications, has not been fully realised. The National Seaweed Forum identified two key areas as being crucial to the development of the Irish seaweed industry: 1) Seaweed aquaculture was assumed to provide the most cost-effective method to meet growing market demand with high-quality seaweed for specific sectors such as human consumption, cosmetics and biotechnology. Additionally, a seaweed aquaculture industry is expected to create attractive and high-skilled jobs, especially in peripheral communities in coastal areas. This is based on the fact that seaweeds of interest to high quality applications are often not bulk species, which are easy to harvest in large amounts. Therefore, with cultivation you strongly increase volume/area, which facilitates harvesting and also standardises quality. Cultivation of a bulk species such as kelp is economically not feasible in Europe. 2) The development and introduction of harvesting machinery suitable for Irish conditions was thought to have a significant impact on the expansion of a viable Irish seaweed industry. As a measure to ensure long-term continuity of raw-material supply of bulk species (e.g. A. nodosum, Laminaria species) the investigation of mechanical harvesting techniques with emphasis on sustainability and environmental impact were prioritised as an R&D area (National Seaweed Forum, 2000). An initial comprehensive study of hand and mechanical harvesting of Ascophyllum nodosum, including an environmental impact assessment, was conducted in the late 1990s (Kelly et al., 2001). In this study, a device similar to the Norwegian Ascophyllum cutter (a flat-bottomed boat fitted with a Vaughan vertical wet-well chopper pump) was used. When hand and mechanical harvesting were compared, there was no significant difference in environmental impact caused by the two methods, but mechanical harvesting was found to be less effective and more expensive than hand harvesting. At present, kelp species in Ireland such as L. digitata, L. saccharina and Alaria esculenta, are harvested by hand but only in small amounts. This means that the natural sustainable resources of kelps of Irish shores are under-utilised. Due to the economic importance of L. digitata and L. hyperborea for alginate extraction and the growing demand for kelp by the phycocolloid and other industries, the introduction of mechanical harvesting is currently being considered for Ireland. Mechanised harvesting enables the harvester to remove large amounts of biomass from an area in a relatively short time. It is therefore essential to develop a suitable management scheme to ensure sustainable exploitation of natural resources and continuous integrity of marine habitats. The objective of the present study is to provide an extensive literature review on kelp research, harvesting and resource management as essential background knowledge for the development of an appropriate management strategy for Ireland. The report addresses the following topics: • Biology of kelps • Biodiversity of kelp forests and ecological significance of kelps • Commercial kelp harvesting in France and Norway (methods, management and environmental impact) • Investigations of kelp in Ireland (Growth rates, biomass, biodiversity of kelp beds, regeneration potential, kelp resources) • Legal framework for seaweed harvesting in Ireland • Conclusions and recommendations
    • Proceedings of the 5th Irish Shellfish Safety Workshop, Rosscarbery, October 28th 2004

      Marine Institute (Marine Institute, 2005)
      This document outlines the proceedings of the 5th Irish Shellfish Safety Scientific Workshop. This event was organised by the Marine Institute, the Food Safety Authority of Ireland and Bord Iascaigh Mhara to discuss the methods and advances of food safety with respect to shellfish health.
    • Karenia mikimotoi: An Exceptional Dinoflagellate Bloom in Western Irish Waters, Summer 2005

      Silke, J.; O'Beirn, F.X.; Cronin, M. (Marine Institute, 2005)
      A protracted bloom of Karenia mikimotoi was present in summer 2005 along the northern half of the western Irish coastline. The onset of this bloom was identified in late May / early June. This event subsequently dissipated over the month of July and was succeeded by a bloom of the same species in the southwest in late July. The bloom was very intense and resulted in discolouration of seawater and foaming in coastal embayments. Major mortalities of benthic and pelagic marine organisms were observed and a complete decimation of marine faunal communities was reported and observed in several locations. Deaths of echinoderms, polychaetes and bivalve molluscs were observed in County Donegal and Mayo, while farmed shellfish and hatchery raised juvenile bivalve spat suffered significant mortalities along the Galway and Mayo coasts. Reports of dead fish and crustacea were received from Donegal, Galway, West Cork and Kerry. Karenia mikimotoi is one of the most common red tide causative dinoflagellates known in the Northeast Atlantic region, and is also common in the waters around Japan. Blooms of this species often reach concentrations of over several million cells per litre and these densities are often associated with marine fauna mortalities. Although cytotoxic polyethers have been extracted from cultures of the species, the exact mechanism of the toxic effect and resultant devastating damages yet remains unclear. It is known in the literature under several different names as the taxonomy and genetics have been studied. It is now known that previously reported names including Gyrodinium aureolum, G. cf. aureolum, G. nagasakiense and G. mikimotoi are synonymous with the current name given to the organism. The visible effects following the mortalities included noticeable quantities of dead heart urchins (Echinocardium cordata L.) and lugworms (Arenicola marina L.) deposited on beaches. Several species of wild fish were also found dead. The bloom coincided with a period of fine weather and tourists visiting the seaside were concerned about the safety of swimming in waters that were obviously harmful to marine organisms on this scale. A public awareness programme was mounted by the Marine Institute with several radio broadcasts, press releases and a website provided to give up to date pronouncements on the event. While there have been several instances of Karenia mikimotoi blooms reported in Ireland over the past 30 years, this scale of mortalities associated with the 2005 bloom were not previously observed. Recording the scale of this event was facilitated by satellite imagery while direct counts of the cells in seawater by the Marine Institute monitoring programme gave very useful information regarding the size and intensity of this event. The mortalities of marine organisms were documented from reports made by various observers and by Marine Institute field surveys.