• East Coast Queen Fishery 1970

      Bhatnagar, K M (Department of Agriculture and Fisheries (Fisheries Division), 1972)
      During July and August, 1970, two Isle of Man boats, equipped for fishing queen escallops (Clamys opercularis), were each licensed for one week by the Department of Agriculture and Fisheries to fish experimentally under the supervision of a scientist from the Department with a view to locating queen beds along the east coast. In August, a few Irish boats also fished for queens. As a result, large quantities of queens were located off the Bray Bank along the east coast and substantial landings of queens were made in Ireland for the first time. This report is in two parts giving the results of (1) a Queen Survey carried out by the Department of Agriculture and Fisheries on the east coast from 12th to 18th November, 1970 and (2) an Analysis of samples taken from fishing boats during the 1970 fishing season.
    • The edible mussel (Mytilus edulis)

      Crowley, M (Department of Agriculture and Fisheries (Fisheries Division), 1970)
      The mussel is one of the commonest bivalve molluscs around the Irish coast but quantity and quality vary greatly from place to place. Ideal conditions for the natural or farmed production of mussels are as follows:- (i) Sheltered bays or inlets; (ii) Firm shingly substrata; (iii) Good food supplies in the water; (iv) Absence of parasites and predators. Mussels on exposed shores subject to excessive water movement are usually slow growing and of poor quality. In other areas, although there is shelter from the action of wave and weather, the bottom may consist of soft mud or sand, neither of which is suitable for the settlement, survival and growth of mussels. Similarly areas may have the necessary shelter and firm substrata for the attachment of mussels, but, because the water does not produce an adequate supply of food material, the mussels do not flourish. Even in areas where there is shelter, firm substrata and plenty of feeding there may be many predators (e.g. crabs, starfish etc.) or parasites (e.g. redworm (Mytilicola intestinalis) and pea-crabs) which often render mussels unsuitable for marketing. Because of these limitations, it is not surprising that many areas of our coast produce mussels which are of poor quality. At present the five centres at which good quality mussels are produced are (a) Carlingford Lough (b) Dundalk Bay (c) River Boyne estuary (d) Wexford Harbour (e) Castlemaine Harbour (Cromane), Co Kerry.
    • Eel Research 1965-1971

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1972)
      The catch of eels for the Republic of Ireland is very low. It averages 125 tons a year, thus comparing unfavourably with such figures as 800 tons for Northern Ireland and 1,500 tons for Holland. Since 1965 experiments have been in progress to find out whether there is any possibility of increasing the production of this valuable fish. A detailed report of the investigations was completed in March 1972 and this leaflet gives a summary of the most important conclusions. The approach to the problem was to make a study of some aspects of the life of the eel, concentrating on lakes where commercial eel fishing was well established. In addition to this some fishing trials were made in the estuaries of rivers such as the Munster Blackwater and the Shannon where no large-scale eel fishing had ever taken place.
    • Eel Research 1972

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1973)
      The national survey of eel stocks was continued in 1972. For the first time the eel population of a river, the Munster Blackwater, was studied. It proved to be the most densely stocked freshwater area sampled to date. It was calculated that between five and ten tons of eels must leave the river each year on migration. Unfortunately the eels were slow-growing and of rather low quality. The eel stocks of Lough Gill and Lough Conn were found t o be poor, heavily overfished and the eels were slow-growing. Two restricted areas which had been subjected to intense commercial fishing for several years, the South Sloblands Channel in County Wexford and the Broadmeadow Estuary, showed poor stocks and will take several years to recover, Unfortunately, eels grow so very slowly (rarely taking less than ten years to reach market size) that their stocks are highly susceptible to damage from overfishing.
    • Eel research 1973

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      Eel research broke new ground in 1973 by beginning a study of elvers and young eels. Elvers enter fresh water in spring and make their ways upriver. Precise information on when they arrive, in what numbers and how far they travel is very limited, although the subject was studied in the early years of the present century. Knowledge of the behaviour of eels in these early stages is essential because we have now proved that the scarcity of eels in many Irish waters is caused by the failure of the small eels to reach them. The situation could be improved by artificial transport of the young eels but first they must be caught and we must find out where and how best to catch them. In 1973 the arrival of elvers happened rather late and many were still on the move from the end of June right up to August. A study of the young eels at Parteen Weir on the River Shannon showed that there were virtually no elvers amongst them. This indicated that elvers took more than a year to travel distance of nine miles to Parteen from the top of the tide.
    • Eel Research 1978-1979

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1980)
      The good prices paid to fishermen for eels have led to an increased interest in eel capture in Ireland. In that regard the results of stock assessments examined in conjunction with records obtained from other European eel fisheries, have indicated that the present national catch could be increased by at least 100% and perhaps by several times as much. Such an improvement could be effected by the overland transport of elvers from collection points near the coast. An operation of this kind in already in progress on the Shannon river system undertaken by the Electricity Supply Board who own the entire fishery. Sampling of eels within that system have indicated that substantial increases in the numbers of growing eels in the lakes and in the numbers of male silver eels captured, have taken place. Since it takes between ten and twenty years from the beginning of a stocking programme for any results to be apparent it is essential to devise a system for making an accurate assessment of the developments. This is the principal aim of the routine sampling of yellow eels which forms the greater part of current research work.
    • Eel Research in 1968

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      Fyke nets for the capture of eels have been in use in some parts of the country since 1961. These are “summer” type nets, laid on the bottom in lakes and river estuaries and having, when set, a maximum height of about 60 cm (2 ft.). Experiments with these nets were made in a number of lakes from July to September. Five students were employed to operate the nets and examine the eels. Each student was supplied with a set of eight nets (sixteen traps with eight leaders arranged in a line) and the nets were fished daily except at weekends or in rough weather. The traps were 1.84 m (6 ft.) long with an opening diameter of 43 cm (16 ins.), the leaders were 4.7 m (18 ft.) long and the mesh size at the cod end was 1 cm (0.4 ins). The areas chosen were Lough Corrib (mainly in the vicinity of the Docros peninsula), Loughs Inchiquin and George, near Corofin, Co. Clare, Loughs Ecnish and Tullyguide, near Killeshandra and Town Lake, Dromore Lake and Dromloona Lake, near Cootehill, Co. Cavan, the latter three by kind permission of Brigadier Dorman O'Gowan. In all cases the lengths of the eels were measured and the stomachs and otoliths of as many as possible were collected. The Lough Corrib eels were also weighed, their weights were used subsequently to calculate the weights of the eels from the other lakes. Examination of the stomach contents and otoliths of the eels has not yet been completed. The indications are that the majority of the eels feed on invertebrates while a small proportion feed on fish. Loughs Corrib and George in the areas fished offer poor feeding while Inchiquin and the County Cavan lakes are rich.
    • Eel Research in 1969

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1970)
      Most of the research effort was concentrated on experiments with summer fyke nets on the lines of the 1968 work (leaflet No. 9). Three zoology students, Messrs. Dermot Douglas, Tommy Hayden and Martin O’Grady were employed on bursaries for the field work and the Electricity Supply Board co-operated on the Shannon System. The standard set of eight nets (sixteen traps with eight leaders, arranged in line) was used on the Corrib system. On account of losses and damage to nets only seven were available for the Shannon but it is unlikely that this made any material difference to the results. When possible fishing took place daily. The figures are based, with one exception, on the total number of days when the nets were fishing, including weekends and stormy weather when they were not lifted daily. The exception was Lough Mask where persistent rough weather made lifting the net impossible for a fortnight. It was found in this case that the smaller eels escaped and the catch was therefore not typical of normal conditions. The nets used had a mesh size at the cod end of 10 mm.
    • Eel Research in 1970

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1971)
      The summer of 1970 was the third in which a standard set of fyke nets was used to make a detailed study of the eel stocks in a particular lake. The lake chosen was Lough Key which lies on the Boyle River, a tributary near the source of the River Shannon. Miss Ann Fortune and Miss Christine Royle, zoology students, were employed on bursaries for the field and some of the laboratory work. The method of working has been described in previous Leaflets (Nos. 9 and 21). In brief it consists of fishing daily with a standard set of eight nets (sixteen traps with eight leaders arranged in line) which have a cod-end mesh size of 10 mm. The eels were measured, weighed and sexed and otoliths and stomachs were preserved for examination.
    • Eel research in 1974

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      The value of eels at present is about 50p per pound, placing them amongst the most highly priced fish. Our studies over the past few years have shown that most of the Irish eel-barfing waters are seriously under stocked. This situation can be greatly improved by artificial stocking.
    • Eel Research in 1975

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1976)
      The national survey of Irish eel stocks was completed in 1975. A definitive report is being prepared and will be published later. The work began eleven years ago and the final phase was a study of the eels in the River Barrow. We have now searched for eels in coastal locations, in river estuaries, rich lakes, poor lakes, mountain streams and lowland rivers rich and poor. This has provided a picture of how and where quantities of eels may be found, how they may best be fished for and managed and how the stocks may be improved for the benefit of the fishermen. The stocks are definitely low, although the annual output of eels is of the order of one hundred tons with a value of over £100,000. About two-thirds of this catch came from the Shannon fishery. In general, fishing is intensive and the scope for improvement in fishing methods is limited. Stocking with elvers however, can greatly increase the catch in the long term and at a value of £1,000 a ton it is clearly worthwhile to go to work on this. The Electricity Supply Board has in fact been engaged in restocking for many years and can expect an increased yield in the near future.
    • The Eel Stocks of the Shannon System and Prospects for Development of the Fishery

      Moriarty, C (Department of the Marine, 1987)
      Lough Neagh has long been known to yield the greatest quantities of eels of any water body in Ireland, the annual catch being in excess of 700 tonnes. The Shannon catchment on the other hand yields less than 100 tonnes per annum. This Leaflet describes work carried out in Lough Neagh and in the Shannon catchment in 1985 and 1986 which has indicated that eels are now more abundant in the Shannon System than in Lough Neagh. The implications are that the stocks in the Shannon System are sufficient to yield an annual catch of as much as 1,000 tonnes and value £2 million. The current capital cost of establishing a two-man crew capable of catching 3 tonnes of eel, value £6,000, is £2,500. Annual running costs per crew are less than £1,000. The large scale exploitation of the fishery would involve much more substantial investment by the owners. Arising from this paper, the Department has raised the matter with the ESB and the Shannon Regional Fisheries Board to agree on a strategy to maximise employment from the fishery.
    • The effects of drainage on the flora and fauna of a tributary of the River Boyne

      McCarthy, D T (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      Arterial drainage helps in the process of land reclamation by lowering the level of the existing river bed and allowing the ground water to run off more quickly. In recent years the Rivers Corrib, Dee-Glyde, and Moy have been drained. The effects of drainage on the fish stocks and the invertebrate fauna of the River Moy have been described by Toner, 0'Riordan and Twomey (1965). In 1968 investigations commenced into the effects of drainage on the invertebrate fauna and flora as well as fish stocks in the Trimblestown, or Athboy, River, a tributary of the River Boyne. The Boyne rises 6.4 km from Edenderry and flows north-east for 112 km to the sea at Drogheda. It has fifteen tributary streams and two lakes in its catchment area of 2,693 square km. A section of the Trimblestovn River which rises at the foot of Slieve na Calligh, Co Westmesth and flows south-east for 35 km to meet the Boyne at the town of Trim was selected. Its shallowness and accessibility made it particularly suitable for the study. The study area 4.8km north of Athboy town, was 146 metres long and averaged 6.1 metres wide. The river flows for its entire length over Carboniferous limestone end the bed of the river consists of gavel and sandy silt, with scattered boulders and some mud in the quieter areas. There are a few pools in this section, the river being composed of riffle areas alternating with flats. The normal flow at this point was 0.77 cubic metres per second, the pH was 7.6 and the alkalinity as CaCo3 was 310 p.p.m. From 1968 and 1970, 57 invertebrate fauna samples from standard areas (0.093 sq.m) were taken with a suber stream bottom sampler. The plant life was mapped and an assessment of the fish population was made, by the depletion method.
    • Escallop fishing around Ireland

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1957)
      There are, at present, two main centres of escallop fishing around the Irish coasts, one situated in the inlets forming the north side of Galway Bay, and the other along this south-west coast from Schull, County Cork, to Valentia, County Kerry, the beds exploited in these areas are all inshore, ranging from a short distance to about two miles beyond low water mark and in depths varying from two to twenty fathoms. Extensive beds are uncommon, most of them being small and located between rocky areas where the bottom is suitable. Escallops are generally taken in the months of October to April. Minimum size limits are enforced.
    • Estimating effort by the Irish gillnet fishery

      Fahy, E; O'Donoghue, S; O'Driscoll, M (Department of the Marine, 1992-01)
      In order to reach an estimate of the amount of gill-net set, potential sources of information are reviewed. The principal enmeshing gears in Irish waters are briefly described. The following sources of information are examined on the extent of the fishery: salmon drift net licence sales figures, the register of fishing vessels, The European Communities' Logbook and, of greatest value, a survey of gears in use carried out in 1991. Additional information is supplied on sales of netting and on landings by gill net, the latter based mainly on limited sampling data. The total length of large mesh bottom-set gill net is calculated as 100,000 km days annually.
    • European Conservation Year 1970: Synopses of talks given at meetings organised by the Fisheries Division of the Department of Agriculture and Fisheries

      Anon. (Department of Agriculture and Fisheries (Fisheries Division), 1972)
      As part of its contribution to European Conservation Year, 1970, the Fisheries Division of the Department of Agriculture and Fisheries organised a series of lectures in Dublin and at centres around the country to indicate what work is being carried out in the division within the conservation field. The Dublin meetings were opened by reading of addresses by Mr. Jackie Fahey, Parliamentary Secretary to the Minister for Agriculture and Fisheries, The Parliamentary Secretary's addresses and those of the chairman, Dr. A.E.J. Went, D.Sc, M.R.I.A., Inspector of Fisheries and Scientific Adviser and synopses of the talks by the other speakers (all from the Department of Agriculture and Fisheries) are given.
    • Experiments with the American Hard-Shelled Clam (Mercenaria mercenaria) 1969

      Gibson, F A; Duggan, C B (Department of Agriculture and Fisheries (Fisheries Division), 1970)
      The American hard-shelled clam (Mercenaria mercenaria) is a valuable bivalve molluscan shellfish in the U.S.A, and Canada. This bivalve is somewhat like the cockle (familiar to most Irish people) or the palourde (Venerupis decussata) which is gathered on some parts of the Irish coast and exported to France. Unlike the cockle which lives in sand, or the palourde which is found mainly in coarse sand and shingle, the hard-shelled clam lives in sandy mud. Some years ago this clam established itself in Southampton Water, on the south coast of England. It is thought that this particular stock originated from live clams thrown overboard from an American liner. Due to the warming effect of the outflow from a large power station near Southampton, coupled with naturally occurring high sea-water temperatures in this area, the clams were able to breed and multiply. Normally the seawater temperatures around the coasts of Gt. Britain and Ireland are too low to permit the clams to multiply by natural breeding.
    • Exploitation and Survival of Reared Salmon Released into the Burrishoole River System

      O'Maoileidigh, N; Browne, J; Cullen, A; McDermott, T; Keatinge, M (Department of the Marine, 1994)
      Hatchery reared salmon smolts have been microtagged using binary coded nose tags and released into Irish rivers since 1980. These tagged fish are intercepted and identified in high seas coastal fisheries and in Irish rivers as adult salmon. The tag recovery programme provides valuable information on the marine survival and exploitation rates of these tagged fish and the return rates back to the river of origin. This leaflet summarises the results for release groups of reared indigenous salmon from the Burrishoole system in Co. Mayo. Marine survival prior to homewater exploitation has been very variable in the period examined. Although homewater marine exploitation rates have varied considerably depending on the fishing areas, they remained high for all areas combined between the years 1982 to 1989 with exploitation rates by coastal fisheries up to 87%. The greater part of the catch is taken in the Mayo area. Exploitation rates have decreased since 1989 and approximately 60% of the returning stock is estimated to have been caught in coastal fisheries in 1993. Survival to the river has also varied with an average of 2.5% of the total number of smolts released returning as adults to the river.
    • Exploitation and Survival of River Shannon Reared Salmon

      O'Maoileidigh, N; Browne, J; McDermott, T; Cullen, A; Bond, N; McEvoy, B; O'Farrell, M; O'Connor, W (Department of the Marine, 1994)
      Following the construction of the River Shannon hydroelectric scheme the Electricity Supply Board (ESB) have maintained a juvenile salmon restocking programme. Tagging of smolts with coded wire tags (microtags) was initiated in 1980 to examine the migration and survival of these stocked fish. In 1991, an estimated 292,000 hatchery reared salmon smolts (micro tagged and adipose finclipped) migrated from the River Shannon, County Limerick. This allowed an assessment to be made of the contribution of these fish to the high seas fisheries at West Greenland and Faroes, and also to homewater net and rod fisheries. Over 12,000 grilse from this release programme were estimated to have been taken by commercial nets with 525 taken on rods and 3,147 surviving to spawn. The return rate of 2 sea winter fish was much lower with 150 taken by commercial nets, 93 taken by rods and 202 estimated to have spawned. The Greenland fishery took approximately 107 potential 2 sea winter fish which is a high proportion of the overall 2 sea winter stock. Tag returns from groups of smolts released by helicopter proved to be highest. Groups released above the dams and which had to navigate through these installations also showed comparatively good returns. Early presmolt and smolt releases (i.e. December and February) did not give as good return rate in comparison to the other release groups.
    • Export and Import of Shellfish 1961-1970

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1972)
      The greater part of all varieties of shellfish and shellfish preparations, produced from Irish fisheries are exported. Markets for this production are located chiefly in Britain and Europe. The home market has been taking a steady proportion of some varieties, notably, lobsters, Dublin Bay prawns (Nephrops), crabs, oysters and escallops. At the same time, considerable quantities of shellfish are imported.