• Establishing boundary classes for the classification of UK marine waters using phytoplankton communities

      Devlin, M.; Best, M.; Coates, D.; Bresnan, E.; O'Boyle, S.; Parke, R.; Silke, J.; Cusack, C.; Skeats, J. (Elsevier, 2007)
      This paper presents a description of three of the proposed phytoplankton indices under investigation as part of a classification framework for UK and ROI marine waters. The three indices proposed for the classification process are (i) phytoplankton biomass measured as chlorophyll, (ii) the frequency of elevated phytoplankton counts measuring individual species and total cell counts and (iii) seasonal progression of phytoplankton functional groups through the year. Phytoplankton biomass is calculated by a 90th percentile measurement of chlorophyll over the growing season (April to September) compared to a predetermined reference value. Calculation of functional groups and cell counts are taken as proportional counts derived from the presence of the indicator species or group as compared to the total phytoplankton count. Initial boundary conditions for the assessment of high/good status were tested for each index. Chlorophyll reference conditions were taken from thresholds developed for previous EU directives with the setting of offshore concentrations as a reference condition. Thresholds for elevated counts of phytoplankton taxa were taken from previous EU assessments describing counts that could be impact negatively on the environment. Reference seasonal growth curves are established using phytoplankton counts from ‘‘high status’’ waterbodies. To test the preliminary boundaries for each index, a risk assessment integrating nutrient enrichment and susceptibility for coastal and transitional waters was carried out to identify WFD waterbodies in England and Wales at different levels of risk. Waterbodies assessed as having low or medium risk from nutrient enrichment were identified as type 1 and type 2 waterbodies, and waterbodies assessed as high risk were identified as type 3 waterbodies. Phytoplankton data was extracted from the risk assigned waterbodies and applied to each phytoplankton index to test the robustness of the preliminary classification ranges for each phytoplankton index.
    • Harmful phytoplankton events caused by variability in the Irish Coastal Current along the west of Ireland

      O'Boyle, S.; Nolan, G.; Raine, R. (UNESCO IOC, 2001)
      Frequent sampling in summer along the western and northwestern coasts of Ireland showed the rapid onshore development of blooms of potentially harmful phytoplankton species. In both 1998 and 1999, concentrations of Gyrodinium cf. aureolum rose by four orders of magnitude to over one million cells per litre in Donegal Bay(northwestern Ireland) in less than 10days. The rapid development of these populations was linked to advection resulting from unfavourable wind-forcing of the Irish Coastal Current (ICG) which runs northwards along the western Irish coast. Current measurements showed that after a particular sequence of changes in wind direction phytoplankton populations could be rapidly advected from areas of slack circulation on the shelf via the ICC into aquaculturally sensitive coastal zones such as Donegal Bay. The model presented is similar to one already demonstrated for the occurrence of toxic events in the bays of southwestern Ireland. Other historical harmful events along the west and northwest coasts relating to substantial losses in both finfish and shellfish culture could also be explained using the model. These include the G. aureolum bloom of 1992, the Prorocentrum balticum bloom in 1997.
    • Irish National Phytoplankton Monitoring (Sites 41–45)

      Silke, J.; Cusack, C. (ICES, 2012)
      The Marine Institute in Ireland carries out a national phytoplankton monitoring programme which extends back to the late 1980s. This includes a harmful algal blooms (HABs) monitoring service that warns producers and consumers of concentrations of toxic plankton in Irish coastal waters that could contaminate shellfish or cause fish deaths. This programme is primarily located along the Atlantic seaboard and Celtic Sea. Scientists working on this monitoring programme have developed an understanding of phytoplankton populations and dynamics around the Irish coastline, especially in relation to those that cause shellfish toxicity. Particular emphasis is put on the detection and enumeration of harmful species. The importance of phytoplankton as an indicator of water quality is also studied and is a key component of the European Water Framework.
    • Nucleic acid tests for toxic phytoplankton in Irish waters-phytotest: Marine Strategic RTDI project AT/04/02/02 - research update

      Maher, M.; Kavanagh, S.; Brennan, C.; Moran, M.; Salas, R.; Lyons, J.; Silke, J. (Marine Institute, 2007)
      The Phytotest project is a 3 year collaborative project funded through the Marine Strategic Programme in Advanced Technologies as part of the National Development plan 2000-2006. The project partners include the National Diagnostics Centre at NUI Galway and MI. The overall objective of the project is the development of nucleic acid tests (molecular methods) for the identification of key toxic phytoplankton species in Irish waters. In the final year of the programme the aim is to transfer the molecular methods developed in the project into MI to support their monitoring service. Currently, the monitoring for phytoplankton species in Irish waters is performed by light microscopy which can easily identify some plankton species based on distinctive morphological traits. Other species in particular, Pseudonitzschia spp. and Alexandrium spp. cannot be identified to species level by light microscopy. Identification of these species requires more sophisticated microscopic techniques such as scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These techniques cannot easily be integrated into a routine testing environment. Molecular methods utilise unique information contained within an organism’s genome in order to identify it. This genetic information can be exploited in a range of molecular test platforms enabling microorganisms to be identified to species level. Additionally, there has been a major drive towards the development of highly automated platforms to support molecular tests for high-throughput testing in routine laboratory settings.
    • Observations on a bloom of Flagellate "X" in the West of Ireland

      Dunne, T. (ICES, 1984)
      In July 1983 major mortalities of farmed trout and salmon were associated with a bloom of an unidentified organism hitherto unrecorded in Ireland. Three further blooms occurred in 1984, two of which were associated with mortalities. The morphology of this organism (Flagellate "X") as observed in 1983 is described.
    • Observed sequential occurrence of phytoplankton and zooplankton in the Dunkellin Estuary, Galway Bay, Ireland

      Byrne, P.; O'Mahony, J.H.T. (ICES, 1993)
      The Dunkellin is a small tidally-dominated estuary to the south-east of Galway Bay in western Ireland. The plankton of the estuary was studied for 18 months between December 1984 and July 1986. This paper presents results on the variation in the sequential occurrenCe of phytoplankton and zooplankton between the inner and outer estuary. Phytoplankton and microzooplankton occurred in high numbers in the spring to autumn months. Highest abundances of phytoplankton and microzooplankton (non-tintinnid ciliates and tintinnid ciliates) were recorded 10 the Inner estuary, whereas mesozooplankton were predominant in the outer reaches.
    • Phytoplankton and microbial plankton of the Northeast Atlantic Shelf

      Silke, J.; Kennington, K.; Bresnan, E.; Cusack, C. (ICES, 2012)
      The Northeast Atlantic Shelf region includes the sites from all coastal waters of Ireland, the Irish Sea, and western Scottish and Norwegian Sea waters. The region was defined by WGPME to include locations on the northern margin of Europe that were outside the North Sea/English Channel influence. The character of sites in the region are shallow, coastal-water sites ranging from sheltered bays on the south coast of Ireland and fjordic sea lochs of Scotland to fully exposed locations on the west coasts of Ireland and Scotland. Bathymetry of the region ranges from shallow embayments to regions of shallow, exposed continental-shelf waters. The topography of the shelf drops rapidly to 80–100 m within 20 km of the coast, where it extends to the shelf edge as a relatively flat plateau. Time-series of phytoplankton data from the Atlantic Shelf exhibit a typical seasonal pattern of temperate waters, with considerable geographical and temporal variation. The well-mixed winter conditions lead to a region-wide strong spring bloom observed at all sites. The ensuing decrease in nutrient levels lead to a variable summer period characterized by stratified conditions in coastal areas and periodic blooms of mixed or occasionally monospecific diatom and dinoflagellate composition. The growth period tails off in autumn, when a secondary bloom may occur in response to increased mixing and breakdown of the summer thermocline. The seasonal cycle returns to a quiescent winter phase, with generally mixed conditions, light limitation, and increased nutrients return. Seasonal stabilization and destabilization of the water column in this region accounts for most of the natural variation in both phytoplankton species composition and biomass.
    • Report on the incidence and implications of phytoplankton blooms on the East Coast and particularly Wexford Harbour, Summer 1984

      Doyle, J.; Dunne, T. (1984)
      The Fisheries Research Centre had a number of reports of discoloured water between Brittas Bay Co. Wicklow and Wexford Harbour and south to Kilmore Quay. Samples of water received from Dr. David Jeffrey, Department of Botany TCD, collected from Penny-come-quick beach, co. Wicklow on June 17th and examined by Tom Dunne in the Laboratory contained dense colonies of Phaeocystis pouchetii - a microscopic algae. Subsequent samples collected by Miss Ann Kiley, Wexford County Council, traced the extent of the bloom as far south as Neamstown near Kilmore Quay. A sample taken at Cullenstown west of Kilmore Quay was clear. Also associated with this bloom were large numbers of needlelike diatoms (Nitzschia spp. More seriously, blooms of another microscopic alga (Prorocentrum minimum) began to develop in early July during the later phase of the Phaeocystis bloom.
    • Review of phytoplankton monitoring 2005

      Moran, S.; Silke, J.; Salas, R.; Chamberlain, T.; Lyons, J.; Flannery, J.; Thornton, V.; Clarke, D.; Devilly, L. (Marine Institute, 2006)
      A national phytoplankton monitoring programme, has been in operation in Ireland since 1986, and fulfils requirements of the EU Council Directive 91/492/EEC. This programme provides an important part of the baseline data in the overall integrated shellfish monitoring programme. The analysis of samples received on a regular basis from a site can provide very important information in assembling a population profile for the area. This helps in crucial decisions, for example in Management Cell Decisions - conducted by representatives from the industry, MI, FSAI and DCMNR - when borderline toxin results are present. Phytoplankton monitoring is also hugely important in the Water Framework Directive, which all EU countries must follow, in developing an index of water quality in Ireland and Europe. The Irish Monitoring programme also gives valuable public health information to County Councils, Environmental Health Officer’s and the public during times of bloom events. This paper provides an overview of phytoplankton sampling, analysis and reporting in 2005. The occurrence of potentially toxic and harmful phytoplankton found in Irish coastal and shelf waters in 2005 is also reviewed and the quality scheme in operation is described.
    • Review of phytoplankton monitoring 2006

      Moran, S.; Silke, J.; Salas, R.; Chamberlain, T.; Lyons, J.; Shannon, S. (Marine Institute, 2007)
      This paper provides an overview of phytoplankton sampling, analysis and reporting in 2006. The occurrence of potentially toxic and harmful phytoplankton found in Irish coastal and shelf waters in 2006 is compared with the previous year. The succession of phytoplankton blooms in Bantry is described and environmental data that may explain the onset of toxic species is described.
    • Review of phytoplankton monitoring programme and research activities

      Salas, R.; Chamberlain, T.; Lyons, J.; Hynes, P.; Silke, J. (Marine Institute, 2008)
      This paper provides a review of the activities of the Phytoplankton Unit in the Marine Institute as part of the National Monitoring Programme for 2007 and compares the findings with those recorded during 2005 and 2006., It also presents an overview of the research activities carried out by the phytoplankton team during the year with a focus on culturing phytoplankton and the introduction of real time PCR techniques for phytoplankton identification.
    • Review of the phytoplankton monitoring programme and research activities in 2008

      Salas, R.; Lyons, J.; Hynes, P.; Chamberlain, T.; Silke, J. (Marine Institute, 2009)
      The National Monitoring programme for phytoplankton is a well established programme and this was shown through the improvement and refinement of Phytoplankton shellfish and finfish sites around the country. One important development in the last 2 years has been to increase the number of sentinel sites. A sentinel site is a designated sampling site where a total community Phytoplankton cell count and identification is carried out. The number of sentinel sites has increased from 11 in 2005 to 24 in 2008. This means a better coverage of all the bays around the country. The number of phytoplankton samples analysed in 2008 has seen an increase from the previous year.
    • Toxic phytoplankton in Irish waters

      Silke, J.; McMahon, T.; Nolan, A. (1995)
      The subject of harmful and toxic marine algae has recently gained a growing public and scientific interest both in Ireland and abroad because of the occurrence of these toxins in shellfish.