• The Fry of Salmon and Trout

      Anon. (Department of Agriculture, 1938)
      Every year large numbers of salmon fry (parr and smolts) are destroyed, sometimes quite unwittingly, by anglers who are unable to distinguish between salmon fry and young trout. Under Section 73 of the Fisheries (Ireland) Act, 1842, it is illegal to take the fry of either salmon or trout. The term “trout fry” has not yet received a legal interpretation but in some Fishery Districts the taking of immature trout below a certain size is prohibited by by-law. The fry of salmon are legally deemed to include also those fish locally called "jenkin" and "gravelling."
    • Salmon and Trout: Natural and Artificial Propagation as Factors in the Maintenance of Stocks

      Anon. (Department of Agriculture, 1939)
      The object of fishery regulations whether statutory or departmental is, in the ultimate, conservation. That is to say, it is sought by the imposition of certain restrictions to ensure such a run of fish for breeding purposes as will increase or at least maintain the stocks. Many citizens profess dissatisfaction with the existing stocks of fish in our rivers and lakes and persistently urge that they should be enhanced by all practical means. Generally the method which suggests itself to such persons is the setting up of a hatchery, to be operated either by stripping fish captured locally or by procuring supplies of ova (eggs) from outside sources. There seems to be a rather widespread belief that such a procedure even on a modest scale is bound to produce immediately beneficial results for the waters concerned. In other words, the operation of a hatchery is expected to offset completely the evils of over-fishing, as well as the damage resulting from illegal activities (whether within or outside the fishing season) and the reduction in stocks caused by predatory birds, fish and mammals added to the pollution of waters by the entrance of deleterious matter. Such a belief is, however, fallacious as it cannot be accepted in any degree without serious reservation.
    • Prawn Fishing

      Gibson, F A (Department of Lands, 1956)
      The common prawn (Leander serratus) is widely distributed around the Irish coasts, but obviously varies in abundance from place to place. This prawn should not be mistaken for the Norway Lobster, sometimes called the Dublin Bay Prawn (Nephrops norvegicus) or with the brown shrimp (Crangon vulgaris). Alive, the common prawn is a grey-brown colour and has blue bands on its legs. The Norway lobster is a pink colour, and its body is profusely covered with white tipped spines. The common prawn also has a projection from its head, called a rostrum, which is absent from the shrimp. As the prawn is of economic importance, some notes on simple methods of capture will be of interest to fishermen.
    • 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.
    • Some notes on crab fishing

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1957)
      Specific fishing on a commercial scale for the edible crab is practised only to a limited extent in this country and, although fairly substantial quantities of edible crabs are landed annually, these are largely the by-product of creel fishing for lobsters and crawfish. These notes give a short account of certain crab fishing methods and record the results of some experimental fishing undertaken by the Fisheries Division.
    • Catch Effort and Size Distributions of the Catch in the Irish Lobster Fishery (1968)

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      The object of this leaflet is to discuss methods of comparing the success (catch per unit effort) of various types of traps for the capture of lobsters and the relationship of the information thus obtained to the lobster stocks themselves.
    • 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.
    • The Torrey Canyon Disaster: A review of methods employed to combat large scale oil pollution

      Griffith, David de G (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      In this review an attempt has been made to collate the central points of the most important of the multitudinous reports which have appeared in connection with the Torrey Canyon oil pollution. The content has been limited to the biological aspects of a large-scale oil spillage and its subsequent treatment, although the importance of tourist amenities also receives consideration in the discussion. Consequently, several related topics which lie outside the scope of the biologist have either been omitted or just mentioned in passing: they include the technical problems of the salvage of oil from a crippled tanker, the control or collection of floating oil, and the administrative organisational requirements for effective action in an emergency of this kind.
    • A Review of the Irish Lobster Fishery

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      Records of the actual numbers of lobsters caught in Irish waters prior to 1887, are difficult to obtain. However, during the last thirteen years of the 19th century, the fishery had assumed such importance as to be included with the other major ones of the period i.e. salmon, herring, mackerel and cod. In 1891, the Inspector of Irish Fisheries, W.S. Green, commented that "the lobster fishery had reached such proportions as to deserve separate reporting". The help of the Coast Guard officers was sought for the task of compiling catch statistics, with the result that, from 1892 until the outbreak of the 1914-18 war, excellent records of the catch in the fishery are available. Since then the system of statistics collection has changed and now both catch and effort in the lobster fishery are assessed. This paper deals mainly with the period 1900 to 1967.
    • Tralee Bay Oyster Investigations (1965-1968)

      Duggan, C (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      Investigations by the Department of Agriculture and Fisheries into the Tralee Bay oyster beds first commenced in a small way in 1965. Since then, especially during the summer of 1968, a more intensive programme has been carried out involving the collection of spat (oyster young) and plankton samples, the study of currents and temperatures in relation to spat-fall (settlement) and, finally, test trials on various types of spat collectors.
    • The Winter Herring Fishery of the North-West of Ireland (1968-69)

      Molloy, J; Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      The 1968/69 winter herring fishery off the Donegal, North Mayo and Sligo coasts began in mid October, 1968 and continued until the end of January, 1969. A total of 63,821 crans were landed during the season as compared with 55,193 crans landed during the 1967/68 season. The majority of the landings mere made at the ports of Killybegs, Sligo and Burtonport. A feature of the season was the increased landings made at Sligo by both local and Killybegs boats.
    • Investigation into the Toxicity of Corexit - A new oil dispersant

      Griffith, David de G (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      In view of the high degree of toxicity (Smith 1968, Simpson 1968) of BP 1002, Gamlen Oil Spill Remover, Dasic Slickgone and other "detergents" used in Cornwall to combat pollution from Torrey Canyon oil, it was considered desirable to investigate the toxicity of a compound marketed as an oil dispersant under the brand name "Corexit 7664", claimed by the manufacturers to be non-toxic to marine fauna. It is produced by the Standard Oil Company of New Jersey and marketed in the U.K. by the Esso Petroleum Company. It is stated by the manufacturers to be a non-ionic surfactant, soluble in fresh water, 5% NaCL solution and isopropanol, and dispersible in fuel and crude oils. It contains no organic halides or heavy metals. The investigations reported in this paper were made in two experiments. In the first, the toxic effects of straight dilutions of Corexit in seawater were assessed. In the second, the toxicity of Corexit-dispersed crude oil was compared with that of crude oil alone, with an attempt to imitate conditions at low tide on a polluted beach. The first experiment was carried out in Bantry, Co. Cork, using material collected locally. The second experiment was carried out in the laboratory of the Fisheries Division, Department of Agriculture and Fisheries, and the material was collected at Sandycove, eight miles south of Dublin.
    • South Coast (Waterford and Cork) Herring Fishery 1968-1969

      Molloy, J P (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      The 1968/69 herring season proper commenced on November 27, 1968 and terminated on February 17, 1969. Prior to November 27, however, some small quantities of herrings had been taken by boats over a large area extending from Hook Head to the Daunt Rock. Fifty nine Irish boats made catches throughout the season and a total of 70,781 crans of herrings were landed which was an increase of 7,438 crans (11%o)n the figure for the previous season. Landings were made on 60 days out of a possible 70. The season, which began later than usual, was very disappointing before Christmas, due mainly to adverse weather conditions and the absence of shoals in inshore waters, After Christmas, however, landings of herrings increased substantially and fishing during January and February was exceptionally heavy, with the result that the total landings for the 1968/69 season were the greatest on record. As in the 1967/68 season, fishing was restricted after Christmas at times due to marketing problems which caused the closure of the ports on a number of occasions. The overall catch would otherwise have been considerably higher. Almost all landings of herrings were made at Dunmore East and Cobh.
    • The Irish shellfish industry 1948-1967

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      The term shellfish is used to group together two very large orders of the animal kingdom, namely the Crustacea and the Molluscs. These orders are not closely related to each other; the main characteristics they have in common being that neither of' them has an internal supporting structure or skeleton. However, they live in similar environments, mainly in the sea, although a few inhabit fresh water, Many hundreds of individual species occur in Irish waters, but only a small number of these are commercially important. These include lobsters, crawfish, Dublin Bay prawns (Nephrops), crabs (all crustaceans), periwinkles, oysters, escallops, mussels, cockles, whelks and clams (all molluscs). During the twenty year period 1948 to 1967, reviewed in this paper, the Irish shellfish industry has changed in many respects. In some sectors methods of fishing have been improved, farming techniques have been introduced and the development of markets on Continental Europe has encouraged the use of improved methods of handling and transport of shellfish to these distant destinations, Nevertheless the rate of expansion of the shellfish industry has been comparatively slow.
    • Lobster Trap Census 1968

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      A census made in July and in September, 1968 of the number of traps used in the Irish lobster fishery has been used in this paper as the basis for an analysis of lobster catch. The catch figures supplied to the Fisheries Division by various collectors have been correlated with the gear used in the 12 maritime counties involved.
    • Freshwater Crayfish 1968

      Moriarty, C (Department of Agriculture and Fisheries (Fisheries Division), 1969)
      The freshwater crayfish inhabits some rivers and lakes in Ireland. The only species known to inhabit Ireland is Astacus palipes. It looks like a lobster but is very much smaller, seldom more than 10 cm (4 ins.) in length. As a rule it hides by day and comes out to hunt at dusk. Apart from the fact that it feeds on various kinds of dead animal matter nothing is known about its feeding habits in Ireland. In other parts of Europe it eats water weed and many kinds of small creatures. The crayfish can be caught easily in special traps which resemble small lobster pots and are baited with raw meat. Boiled crayfish are excellent food but are rarely eaten in Ireland. In other countries, especially Sweden, they are regarded as luxury items and are sold at high prices. Crayfish caught in Ireland for export to Sweden should be worth about 5/- per pound to fishermen.
    • 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.
    • 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.
    • Crawfish Investigations 1966-68

      Molloy, J P (Department of Agriculture and Fisheries (Fisheries Division), 1970)
      The fishery for crawfish (Palinurus elephas) in Irish waters has previously been described by Gibson and O'Riordan (1965) and by Gibson (1967). Molloy (1968) has given some details of the scientific work done on this species in recent years. One of the most important aspects of this fishery is that both lobsters and crawfish are exploited simultaneously by boats which use the same type of traps and baits for the two species. Neither the location nor extent of the fishery has shown any marked change since it first became an important aspect of the Irish fishing industry but the annual landings still show considerable variations. These fluctuations in the yearly catch would seem to depend more on the duration of the season and its length, rather than on changes in stock abundance (Gibson 1967). The annual landings (to the nearest thousand fish) since 1951 are shown. The landings in 1968 were surprisingly low for a season which was marked by exceptionally fine weather.
    • The Herring Fisheries of Ireland

      Molloy, J P (Department of Agriculture and Fisheries (Fisheries Division), 1970)
      Not since Farran (1941) published his paper, entitled "The herring fisheries in Eire, 1923 - 1941" has an attempt been made to describe the herring fisheries of Ireland. The purpose of this paper, therefore, is to provide information about the various fisheries around the Irish coast in the decade from 1960 to 1969. For convenience, the coast has been divided into five areas, namely the east coast, the south coast, the southwest coast, the west coast and the northwest coast. The principle ports and major herring grounds, the type of boats and gear used, the seasonal abundance and total catch, the type of herring caught, with regard to size, condition, number per kilogram and fat content, the present methods of disposal of the catch and any other relevant details are described for each area.