Now showing items 41-60 of 181

    • 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.
    • A study of some invertebrate resources within Bertrabouy Bay, Connemara

      Minchin, D (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      This study of invertebrates in Bertrabouy bay was a by-product from an investigation of the distribution of escallops in Connemara examined by SCUBA diving and dredging. The bay is about 5 miles by 2 miles and has many small inlets and islands; it deepens to 18 fathoms near its entrance. Most of the escallops and lobsters are fished from the centre of the bay to its entrance. Small populations of escallops are fished with hand nets at the head of the bay where oysters were once cultivated on banks that are often covered with eelgrass. Cluaisíns are picked from the banks and winkles are found intertidally throughout the bay. In the course of the study an unexploited lobster population was discovered at the centre of the bay. Crawfish are taken at the bay entrance where razorfish and otter clams are also found. The oyster banks could be examined for future development and the use of a portable shellfish harvester to collect razorfish might be investigated.
    • Salmon movements in Galway Bay in 1978 and 1979

      McCarthy, D T (Department of Agriculture and Fisheries (Fisheries Division), 1980)
      In 1978 tagging investigations commenced into the origin of salmon caught in drift nets in Galway Bay. This fishery began in 1969 with a catch of 355 fish and, by 1975 had increased dramatically to 33,607. However the catch declined to less than half the maximum and in 1979 was down to 15,171. There are 76 drift net licences in the Bay which incorporates two fishery districts, Galway and Connemara. The vessels used vary from 5 metre currachs to 20 metre trawlers. The majority of the boats are half deckers of between 9 and 11 metres. The fishery starts in mid-May but the bulk of the catch is taken in June and July. The main component of the catch is grilse with an average weight of 3 kg. During the period fishing is carried on over 24 hours daily except for the weekly close season time. The fishery extends from west of a straight line from Spiddal Harbour to Blackhead, Co Clare in the east , and from Slyne Head to Hag's Head, Co. Clare in the west and also incorporates the Aran Islands. Drift nets are shot at right angles to the coastline in roughly a north-south direction, all vessels staying quite close to land, the furthest distance out being 2km. The maximum length of net permitted in the area is 730 metres or 800 yards. The majority of boats fished nets of this length; however some of the smaller craft used nets as short as 300 metres. All nets are 30 meshes deep. Throughout the programme fish were tagged using Lea's hydrostatic tags described by Went (1951). As in previous tagging programmes, recovery baths were used to ensure that only the fittest fish were released after tagging.
    • Herring fisheries on the South and South West coasts 1975-76

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1976)
      The quantities and value of herring landed during the 1975/76 herring season off the south coast are reviewed. The quantity landed showed a further serious decrease due to a decline in stock size which has occurred in recent years. This decline in stock size is due to a failure of recruitment and a continuation of a fishing rate that is too high. The present conservation measures are not adequate to protect this stock and it is considered necessary by the liaison committee to the International Council for the Exploration of the Sea that all herring fishing in the Celtic Sea should be stopped for a period if the stock is to be restored to its former strength.
    • Parasitology of Irish Mussels

      Crowley, M (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      Investigations of the distribution of three parasites of mussels, an internal copepod parasite of the gut (Mytiliocola intestinalis), an external decapod parasite in the gill region (Pinnotheres pissum) and an annelid shell parasite (Pylodora ciliata) were carried out from September 1974 to May 1975. Samples from 28 locations around the Irish coast were investigated. One hundred mussels from each sample were weighed, measured in 5 mm groups, boiled and the following parameters were determined as percentages of the whole mussel:- a. Shell: b. Meat; c. "Loss"
    • The Summer herring fishery in the Irish Sea in 1974

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      In 1974 the landings of herrings taken by the Irish fleet from the summer herring fishery in the north western part of the Irish Sea increased considerably and were valued at over £277,000. The fishery is based on two different races of herring each having different spawning areas. At present, both stocks are rather small and catches are dependant to a large extent on the influx of young fish each summer. In this situation controls are necessary to prevent the over-exploitation of the adult stock and certain conservation measures are suggested. The operating expenses of boats in this fishery could be reduced considerably by co-operation in the transport of catches from the fishing grounds to the home ports.
    • 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.
    • Movement of salmon from the south coast of Ireland in 1973-1974

      McCarthy, D T (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      In 1973 tagging investigations were started into the origin of the salmon stocks being exploited in the West Cork area (8º0'W to 10º10'W) along the south coast of Ireland. The vessels used varied from six metre open boats to twenty metre trawlers, the average length was 10.5 metres (1972 survey involving 276 boats). Fishing is carried on over the twenty four hours. Up to 1973 nets were 30 mashes deep: in that year nets of 60 and up to 98 meshes were introduced, and during the 1974 season most boats fished nets of 68 meshes deep. The length of net varied from 400 metres to 1.6 km. Nets were shot at right angles to the coast in roughly a north-south direction, all vessels staying quite close to land, the furthest distance out being approximately 2 km from land. Most fish were caught in the bottom portion of the net during the hours of day-light but at night or in rough weather about half the catch were caught in the top portion of the net.
    • Interesting recaptures of tagged salmon in 1974

      Went, A E J (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      In a previous issue in the Fishery Leaflet series (No 58, 1973) I gave a list of interesting recaptures of tagged salmon in Irish waters in the year 1973. In this Leaflet I propose to give details of similar fish in 1974 and of some tags recovered in earlier years but not reported until 1974.
    • Making more money from Periwinkles

      Crowley, M (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      Each year about £250,000 worth of periwinkles are picked on our shores. This makes them far and away the most valuable molluscs in our fishing industry. What is more, the value might be doubled if the catch were to be handled carefully. The fact is that, although they appear very tough, the periwinkle are in some ways delicate animals and rough treatment kills many of them. An important fact in the periwinkle industry is that the resource is a natural one which costs little to exploit. No equipment is required to harvest them because they are simply picked by hand when the tide is out.
    • The Clogherhead herring fishery 1971-73

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      Landings of herrings have occasionally been made at Clogherhead during the last twenty years. The amounts however have varied considerably, the variations being caused both by changes in the availability of herrings and by the effort of the local fishing fleet. Throughout the last few years the scarcity of herrings throughout Europe has resulted in a very good demand and considerable attention is now being paid to the herring stocks in the northern part of the Irish Sea. The annual catches in tons since 1951 in the ICES statistical area VIIa (Irish sea) are shown. These figures have been altered to include landings made in the Isle of Man and to exclude landings made at Dunmore East in the year 1960-1966. Also shown are the landings made along the eastern Irish coast and the landings made at Clogherhead. After considerable fluctuations in the nineteen sixties, the total catch has risen dramatically since 1969. This increase is particularly evident in the catches made from the Isle of Man fishery. In 1969 also the Irish catch increased considerably because of the establishment of a fish meal factory at Mornington. Incidentally almost all the herrings taken from area VIIa are taken from that portion which is north of a line drawn from Dublin to Liverpool.
    • Herring investigations on the North West and West coasts 1974-75

      Molloy, J; Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      The main herring fisheries off the Donegal, Mayo and Galway coasts during 1974/75 are reviewed. Landings in all areas decreased considerably and it is thought that this was due mainly to the very poor weather. Recruitment of young fish to the adult fishery was about average off Donegal and slightly better off Galway. The relationship between these herrings to one another and also to those herring exploited off the Scottish coast is discussed.
    • Herring fisheries on the south and southwest coasts 1973-74

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      The 1973/74 winter herring fishery off the south coast began in the week ending 10 November 1973 and ended on 26 February 1974. Some small landings were however made in the weeks before 10 November. The total landing at the ports of Dunmore East and Cobh amounted to 62192 cran. This was 47109 crans lower than the figure for the previous year and was in fact the lowest figure since the 1966/67 season. Seventy three boats, ten less than in the previous season, took part in the fishery. In the interest of conservation of the stocks it had been agreed prior to the opening of the season that no fishing should take place on Sunday nights. This practice was maintained throughout the season with the result that fishing only took place on 58 days out of a possible 90 days. Continuous broken weather throughout January and February also severely hampered fishing operations and because of this the fleet operating from Cobh was able to fish on only 16 nights from Christmas until the 28 February.
    • Herring fisheries on the South and South West coasts 1974-75

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1975)
      The important herring fishery which takes place during the winter months off the South Coast is reviewed. The fishery, which exploits the Celtic Sea Stock of herring, yielded over 68,000 cran in 1974/75 compared with 62,000 cran in the previous season. However, because of poor prices, the value of the fishery declined, from £1.4 million in 1973/74 to £1.3 million. The increased landing, despite abnormally severe weather in January, were attributed to a corresponding increase in effort, as herring were generally considered to be much less abundant. Scientific examination showed that for the second year in succession the recruitment of three year old herring was very low, and this, coupled with the continued high fishing rate means that the total stock is now at its lowest strength since the middle fifties. The autumn fishery off the South West coast was a disappointing one because of decreased catches.
    • Herring investigations on the north west and west coasts 1973-74

      Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      While the main herring fishery off the north-west coasts covered the period October 1973 to February 1974, a considerable quantity of herrings was also landed during the period March - September 1973. The section of this report covering the north-west coast is thus divided into two sections, that concerned with the period March to September 1973 (the off season) and that with the period October 1973 to February 1974 (the main season). A further section deals with the fishery off the County Galway coast.
    • 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.
    • List of fishery leaflets numbers 1 (1938) to 58 (1973)

      Anon. (Department of Agriculture and Fisheries (Fisheries Division), 1974)
      These Leaflets provide a medium for distributing information on various aspects of fishery research and development undertaken by officers of the Department. 58 Leaflets have been published to date (January 1974). A list is attached.
    • Interesting recaptures of tagged salmon in 1973

      Went, A E J (Department of Agriculture and Fisheries (Fisheries Division), 1973)
      In a recent paper (Went, 1973) I gave details of movements of salmon to and from Irish waters based on returns from foreign centres of fish tagged in Ireland and of foreign tagged fish recaptured in Irish waters, This note gives details of the recaptures made in 1973 on similar lines.
    • Lobster trap census 1972

      Gibson, F A (Department of Agriculture and Fisheries (Fisheries Division), 1973)
      This leaflet continues the information provided by Fishery Leaflets Nos. 11, 23, 26, and 39. There was little change in the types of Lobster fishing gear in use in 1972 compared with previous years.
    • Herring investigations on the North-west and west coasts 1972-1973

      Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1973)
      Although the main herring fishery off the north west coast in 1972/73, covered the period from October 1972 to February 1973, a considerable quantity of herrings was also landed during the period March to September 1972. The section of this report covering the north west coast is thus divided into two sections, that concerned with the period March to September 1972 (the off season) and that with the period October 1972 to February 1973 (the main season). A further section deals with the fishery off the west coast, in Galway Bay.