• The distribution and abundance of cephalopod species caught during demersal trawl surveys west of Ireland and in the Celtic Sea

      Lordan, C.; Warnes, S.; Cross, T. F.; Burnell, G. M. (Marine Institute, 2001)
      Distributional and abundance data on seventeen cephalopod species from three demersal trawl series are presented. Data from one the CEFAS March Celtic Sea Groundfish Survey cover the years 1994-1998 inclusive and a depth range of 57-580 m. Data from two Marine Institute surveys was for October-November 1997 only. One of these surveys was west and south west of Ireland between depths of 27-328 m, the other was conducted in deepwater (520-1174 m) to the northwest. Eleven cephalopod species were caught (14,981 individual cephalopods) during the five CEFAS surveys. Spatial and bathymetric distribution data are presented for the species caught and the interannual variability is discussed. The most numerous species in catches was Loligo forbesi (n = 6,803), however, the highest biomass caught was Illex coindetii (418.3kg). Alloteuthis subulata were common close to shore in water depth of less than 75 m. Swept area density estimates are reported for the most abundant species in catches. Ten cephalopod species were caught during the Marine Institute west coast groundfish survey (774 specimens were examined out of an estimated 8,712 caught). The results show broadly similar patterns in species composition, distribution and abundance to the CEFAS survey. Todaropsis eblanae was the second most numerous species in the survey. Only six cephalopod species (n =196) were caught in the Marine Institute deepwater trawl survey. Todarodes sagittatus was the most common species caught. Deepwater octopods including Benthoctopus piscatorum, Benthoctopus ergasticus and Opisthoteuthis massyae were also caught. This chapter provides a base line of data on cephalopod species which are caught in trawl surveys west of Ireland and in the Celtic Sea.
    • Distribution and ecology of oysters, Ostrea edulis (L.) in Kilkieran and Bertraghboy Bays, Connemara, Co. Galway

      Barry, M D (Department of Agriculture and Fisheries (Fisheries Division), 1981)
      An account of Kilkieran and Bertraghboy Bay oysters is presented, including data on their distribution and ecology in these bays. Growth and population structure are compared with other oyster-producing areas in Ireland. These data are reviewed in relation to the feasibility of redeveloping such areas of former extensive oyster production.
    • The Distribution of Irish Char (Salvelinus Alpinus)

      Went, A. E. J. (Department of Agriculture and Fisheries [Fisheries Division], 1971)
      Char* (Salvelinus alpinus) are rare in most places in Ireland to-day but they were formerly more widespread and abundant. About twenty-five years ago the Fisheries Division of the Department of Agriculture and Fisheries started to offer rewards for char submitted for examination and this has had the result of providing specimens which would otherwise have been lost. Many of these specimens wcre taken on rod and line but in recent years considerable numbers have been obtained in connection with either the improvement schemes of the Inland Fisheries Trust, Inc. or investigations concerned with the effects of drainage operations on Lough Conn.
    • The Distribution of Mytilus edulis and Anomid Larvae in Kilkieran Bay, Co. Galway

      Wilson, J H (Department of the Marine, 1987)
      The temporal and spatial distribution of Mytiius edulis and Anomiidae larvae were recorded in Kilkieran Bay, Co. Galway, during 1984 and 1985. Only larvae close to settlement (M. edulis larvae > 250 µm length and Anomiid larvae > 160 µm length) were considered. M. edulis larvae were commonest in late July, mid-August and early September 1984 and in early May, mid-June and early September 1985, while Anomiid larvae were commonest in late June and rnid-July 1984 and mid-June and early September 1985. M. edulis larvae were generally found in higher densities at the mouth of the bay, while Anomiids were more evenly dispersed, with high concentrations over the oyster beds. There was no significant (P < 0.05) net import of either species of larvae into the bay over tidal cycles.
    • Distribution of oyster Ostrea edulis, mussel Mytilus edulis and Anomiid larvae in Bertraghboy Bay, Co. Galway

      Wilson, J H (Department of the Marine, 1988)
      Concentrations and shell lengths of Mytilus edulis, Ostrea edulis and Anomiid larvae were recorded from April to October 1985 in Bertaghboy Bay, Co. Galway. The gamete volume fraction off eggs in female mussels was recorded in an introduced cultivated population of mussels in the inner bay during 1985. Oyster larvae were commonest in July and September, but were concentrated in the upper bay. Mussel and Anomiid distributions were more variable. While the commercial stocks of mussels in the bay contribute to the larval pool, this input is small in relation to that from other sources.
    • The Distribution of the crayfish Austropotamobius pallipes (Lereboullet) in Ireland

      Lucey, J.; McGarrigle, M. L. (Department of Agriculture and Fisheries [Fisheries Division], 1987)
      The distribution of Austropotamobius pallipes, the only freshwater crayfish recorded from Ireland and presumed to be an old native, is described using some 300 records collected since 1976: the positive and negative loci from regularly sampled rivers and streams are used to provide a baseline from which any future changes in distribution can be monitored. Although absent from some regions, most notably the south-west (south of the Dingle-Dungarvan line) and north-west (County Donegal), crayfish are widely spread in the country principally in Carboniferous Limestone areas. The natural chemistry characteristics of the river and stream sites supporting crayfish had the following ranges: pH 7.2 - 8.4, alkalinity 34 - 356 mg/l and hardness 47 - 402 mg/l. Factors which might be important in influencing distribution of A. pallipes in Ireland, including pollution, predation and disease, are discussed.
    • Distribution patterns of ichthyoplankton communities in different ecosystems of the Northeast Atlantic.

      Dransfeld, L; Dwane, O; Zuur, A F (Wiley-Blackwell, 2009)
      Results are presented of an extensive ichthyoplankton survey that covered the continental slope, the offshore banks and oceanic regions west of Ireland. Oceanographic measurements revealed domes of cold, less saline water over the Porcupine, Rockall and Faroese Banks, constituting Taylor columns. The most species-rich stations were those found on and close to the offshore banks and the shelf edge. Larvae found in these areas were mainly from demersal fish species, including some commercial species such as haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt (Walbaum, 1792), ling Molva molva (L.) and witch Glyptocephalus cynoglossus (L.). The deep water stations of the Rockall Trough and the north and west stations off the Rockall and Hatton Banks were characterized by a low number of species and high numbers of individuals of mesopelagic species such as Maurolicus muelleri and Benthosema glaciale. Results from multivariate statistical analysis confirmed that species compositions varied significantly at different sites and were related to environmental conditions, whereby sites of similar temperature, salinity and bottom depth harboured similar species assemblages. Generalized additive mixed modelling was used to model the relationship between species richness and environmental variables and confirmed that there was a significant negative relationship between species richness and bottom depth indicating that the offshore banks and the slope stations present favourable habitats for a large number of species.
    • Distribution, population structure, growth and reproduction of the razor clam Ensis arcuatus (Jeffreys) (Solenaceae) in coastal waters of western Ireland

      Fahy, E.; Norman, M.; Browne, R.; Roantree, V.; Pfeiffer, N.; Stokes, D.; Carroll, J.; Hannaffy, O. (Marine Institute, 2001)
      Samples of razor clams, Ensis arcuatus, the species which makes up the majority of landings from the west coast of Ireland, were collected by commercial fishery methods, in association with the dredge fishery and by scuba diving, from three locations off the coast of Co Galway. E. arcuatus occupies coarse sand (of maerl and shell fragments) and rarely co-exists with the other common species of the region, E. siliqua. E. arcuatus were aged, an age-length-key devised for them, and growth parameters (Linf, k and t0) were calculated. Their maturation state was established by histological examination. Evidence suggests that Ensis arcuatus is mainly a spring spawner, although some spawning appears to take place in most months, with a spatfall in June/July. Maturation commences in its third year. Asymptotic length is achieved at 10 years, approximately, and there was little variability in growth among the three sampling areas or between the sexes. In a small bed of razor clams in Cill Chiarain Bay, Co Galway, there would appear to have been a spatfall in most, if not all, of the past 15 years. The quantitative distribution of E. arcuatus in a single bay within the boundaries of Comharchuman Sliogeisc Chonamara Teo, Co Galway, was estimated by divers salting quadrats of 0.33 m2. The razor clam community is divided into a generally distributed fraction occurring at low density (described as the non-bed) and at a relatively higher density (described as the clam bed). The bed was situated in the lee of reefs, which is usually the case for this species along the Atlantic seaboard. More than 90% of the biomass was above the E.U. minimum size limit.
    • A diving study on Dublin Bay prawns Nephrops norvegicus (L) and their burrows off the east coast of Ireland

      Hillis, J P (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      During 1971 a team of divers studied the structure and numbers of entrances of burrows of Nephrops norvegicus in the Irish Sea off Clogherhead and counted their numbers in plots of 28sq.m area. Numbers of entrances found ranged from one to six with a peak at 3 and the densities of Nephrops norvegicus found ranged from 1 per 2.5sq.m downwards.
    • Donegal Bay Herring Investigations, 1967/68

      Bracken, J. J.; Phillips, D. (University College Dublin, 1968)
    • The Donegal Mackerel Fishery

      Molloy, J; Kennedy, T D (Department of Fisheries and Forestry (Trade and Information Section), 1980)
      Irish Mackerel landings have increased dramatically, from less than 2,000 tonnes in 1970 to nearly 30,000 tonnes in 1978. The development of this fishery can be ensured only if a satisfactory management plan is drawn up. To provide the basis for such a plan a major investigation of the Donegal stocks was launched by the Department of Fisheries in 1978 and will continue for some years. At the same time the fishery scientists of other countries are studying other parts of the same mackerel stock and their results are discussed at an annual meeting in Copenhagen. These results are the basis for the total allowable catch imposed by the EEC.
    • A Draft Marine Research Plan for the European Atlantic Sea Basin: Discussion Document

      Marine Institute; Marine Board-ESF (Marine Institute & Marine Board-ESF, 2011)
      A key deliverable of Work Package 6.1 of the FP7 SEAS-ERA Project (May 2010 – April 2014) is to develop a draft Marine Research Plan as an input to the preparation of a Strategic Marine Research Agenda for the European Atlantic Sea Basin. This Discussion Document is designed to engage European Atlantic stakeholders in a wide ranging debate on the content and priorities to be addressed by such a draft Research Plan and will be used by the SEAS-ERA Atlantic partners to inform a series of Consultative Stakeholder Workshops scheduled to take place in 2012 (www.seas-era.eu/np4/events).
    • Drama: 5th and 6th Class: A hermit crab's quest to find a new home

      Marine Institute (Marine Institute, 2017)
      The aim of the lesson plan if for the children to extend playing in role and in character as well as develop the ability to accept and maintain a brief that has been decided on by the teacher. The children will develop the ability to co-operate and to communicate with others in helping to shape the drama. The activities will enable students to become familiar with the seashore habitat and seashore species. The lesson plan can also be used to help children become aware of litter issues on the seashore.
    • Drama: 5th and 6th Class: A whale's tale : adventures of living in the ocean

      Marine Institute (Marine Institute, 2017)
      The aim of the lesson plan if for the children to extend role playing in character and develop their ability to accept and maintain a brief that has been decided on by the teacher, as well as develop the ability to co-operate and to communicate with others in helping to shape the drama. The students will become familiar with the marine habitat and marine species. The lesson can also be used to learn about the human impacts affecting animals that live in the ocean and developing solutions to create change. (Note that this lesson plan is an extension of the Explorers Lesson Plan: A Whale’s Tale – Science - Living things).
    • The drivers and dynamics of fisher behaviour in Irish fisheries

      Davie, S. (Galway Mayo Institute of Technology, 2013)
      It is widely acknowledged within the scientific community that a single species approach to European mixed fisheries can result in species-specific advice inconsistent with multi-species management objectives. Within the reformed Common Fisheries Policy a move toward mixed fisheries and ecosystem based management is encouraged. The overall objective of this research was to improve understanding of the complex targeting behaviour undertaken by commercial fishers. Whereby, improved understanding will enhance the ability to predict the responses to future mixed fisheries management measures and changing economic conditions within the Irish fishing industry. Irish métiers (groups of homogeneous fishing trips) highlight the complexity of fishing activities within the Irish fleet, having identified 33 otter trawl métiers and 19 in the remainder of the fleet. Métier dynamics identified over compensation to introduced management, resulting in effort displacement and increased temporal specific fishing pressure. Therefore were deemed as appropriate base units for all subsequent analyses. Two economic variables, operational fishing cost and trip landings value, considered to represent important drivers were developed. This lead to application of a general additive model to estimate and predict fuel consumption estimates according to fleet segment definitions. A linear mixed effects model with random vessel effect was developed as a method of standardising value generating an index of value per unit effort. This identified kilowatt fishing days as the most appropriate effort measure. The final investigation stage successfully amalgamated the knowledge gained into the formulation of novel Markov transition probability for a multinomial model to predict fisher métier strategy choice. This is to be incorporated into management strategy evaluation, aiding the assessment and possible impacts of future management proposals on the Irish fleet and commercial stocks around Ireland. Developments presented will benefit the progression toward optimising sustainability within a mixed fisheries approach to management through incorporation of economic considerations.
    • The drivers of sea lice management policies and how best to integrate them into a risk management strategy: An ecosystem approach to sea lice management.

      Jackson, D; Moberg, O; Stenevik Djupevåg, E M; Kane, F; Hareide, H (John Wiley & Sons Ltd, 2018)
      The control of sea lice infestations on cultivated Atlantic salmon is a major issue in many regions of the world. The numerous drivers which shape the priorities and objectives of the control strategies vary for different regions/jurisdictions. These range from the animal welfare and economic priorities of the producers, to the mitigation of any potential impacts on wild stocks. Veterinary ethics, environmental impacts of therapeutants, and impacts for organic certification of the produce are, amongst others, additional sets of factors which should be considered. Current best practice in both EU and international environmental law advocates a holistic ecosystem approach to assessment of impacts and risks. The issues of biosecurity and ethics, including the impacts on the stocks of species used as cleaner fish, are areas for inclusion in such a holistic ecosystem assessment. The Drivers, Pressures, State, Impacts, Responses (DPSIR) process is examined as a decision-making framework and potential applications to sea lice management are outlined. It is argued that this is required to underpin any integrated sea lice management (ISLM) strategy to balance pressures and outcomes and ensure a holistic approach to managing the issue of sea lice infestations on farmed stock on a medium to long-term basis.
    • The Dublin Bay Prawn

      Marine Institute (Marine Institute, 2006)
      Nephrops norvegicus, also know as Dublin Bay prawns and Norwegian lobster, are the second most valuable species fished by the Irish fleet. In 2002 landings were worth almost €28 million. Nephrops are also a very important species for the processing industry in Ireland that use prawns to produce the value added product 'scampi'. Marine Institute scientists have spent many years researching the biology and stock dynamics this commercially important species. Nephrops is a widely distributed species but despite its common name, the “Dublin Bay Prawn”, this species is not found in Dublin Bay. It is found, however, in the Irish Sea, the Celtic Sea and off the West Coast of Ireland. It is also found from Iceland to Morocco and into the Mediterranean as far as Egypt, occurring at depths from 15m to 800m.
    • The Dundalk Cockle Cerastoderma edule Fishery in 2003-2004

      Fahy, E.; Carroll, J.; Murran, S. (Marine Institute, 2005)
      A cockle fishery in Dundalk Bay has been infrequently documented since 1970. Cockle bearing sands and muds are 44.5 km2 in extent. The bay, which is in an SPA and a cSAC also supports large numbers of overwintering birds, of particular relevance is the oystercatcher (Haematopus ostralegus). In 2003 and 2004 when an assessment of the fishery was undertaken, cockles ranged from 0 to 8+ years of age, but the vast majority were 0 and 1+ animals. Growth was rapid and 53% of asymptotic length (49.1 mm) was achieved at the first winter. In agreement with observations elsewhere, the density of the rapidly growing animals was very low. The estimated cockle biomass in spring 2004 was 1,654 tonnes comprising 143 million animals. A survey undertaken in spring 2004, suggested that spat falls contributing to the population may not have been evenly distributed throughout the Bay. Condition factor in 2003 and 2004 did not conform to an expected seasonal pattern, suggesting that some parts of the area supported better growth rates than others. Cockle landings from this fishery are of good quality. Cockle size is at the upper end of the range in Britain and Ireland and the majority of individuals landed by suction dredging were 1+ years old. Raked landings contained more 2+ cockles than suction-dredged ones. Damage to cockles discarded by suction dredging followed the pattern reported elsewhere and damage rates increased with the size of the animals. Some cockle landings have probably always been made in Dundalk Bay by picking and raking, but 2001 marked the beginning of an expansion of the dredge fishery, whose landings exceeded 200 tonnes in 2004. The necessity for controls and management of this fishery in the context of EU legislation and particularly within the constraints of the Habitats Directive is briefly examined.
    • The Dunmore East Herring Fishery, 1958-59

      Bracken, J. J. (Department of Lands, 1959)
    • Dunmore East Herring Investigations, 1965/66

      Molloy, J. (Department of Lands, 1966)