• The Assessment of the Western Mackerel Stock

      Molloy, J (Marine Institute, 1996)
      The mackerel fishery is one of the most important components of the Irish fishing industry. The annual Irish quota is based on the scientific assessments of the size of the spawning stock. These assessments are based on the mackerel egg surveys which are carried out every three years and on the age composition of the total catches. The assessments have indicated that the stock in recent years has declined substantially and is now below 2 million tonnes. Predictions on the development of the stock indicate that it will decline even further unless catches are substantially reduced. The management target for the stock is that it should be rebuilt to a level above 2 million tonnes as quickly as possible. The decline in the stock has resulted in severe reductions in the Irish annual quota and this in turn has had a serious effect on both the catching and processing sectors of the industry.
    • 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.
    • The Closure of Herring Spawning Grounds in the Celtic Sea and Div. VIIj

      Molloy, J (Department of the Marine, 1989)
      The development of the demand for roe from the Celtic Sea has resulted in an intensification of the fishery for herring while the shoals are on the spawning beds. Stocks at this time are at their most vulnerable and uncontrolled fishing could lead to a repetition of the disaster of the 1970s. At the same time, no effort must be spared in maximising the profit from such a lucrative fishery. The problems arise from the fact that the type of herring required by the Japanese market is very specific and large quantities of unsuitable fish may be caught and discarded. Furthermore, because fishing takes place in the breeding area, there is an obvious risk of seriously disrupting all spawning. This paper presents some of the aspects that must be considered so that on the one hand maximum catches may be obtained and on the other the long-term survival of the fishery may be guaranteed. In particular, the reasons for the closure of selected spawning areas are explained.
    • 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.
    • The fat content of Irish herring

      Molloy, J; Cullen, A (Department of Fisheries and Forestry (Trade and Information Section), 1981)
      The fat content in herrings determines the way in which these fish are presented for human consumption. For example, a high fat content is good for kippering, whilst low fat is suitable for marinating. The Department of Fisheries & Forestry has for many years provided the trade with the fat content data they require. The information is based on routine analyses of herring samples which are now made regularly at the Fisheries Research Centre. Sufficient data have been collected over the past ten years to prepare graphs of the mean monthly fat contents in our four main herring fisheries. These graphs may be used to estimate when herring of a particular fat content will be available. This Leaflet presents the essential data and gives an explanation of the biological background of the changes in fat content.
    • 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 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.
    • The herring fisheries on the South and south West coats 1976-77

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1977)
      The quantities and values of herring landed during the 1976/77 herring season off the south coast and during the July to November period off the south west coast are reviewed. In both areas there was a further serious decline in the catch - mainly due to a continuing very poor rate of recruitment of young herring to the adult stock. In the Celtic Sea the total international catch during 1976/77 was only 7,000 tonnes compared with 48,000 tonnes in 1969, while the total Irish catch of approximately 3,000 tonnes was the lowest since the mid-fifties. The immediate aim of any management policy for the Celtic Sea herring stock must be to rebuild it to a level of at least 40,000 tomes. It is, at present, estimated to be below 10,000 tonnes. This can only be done by having a complete ban on all herring fishing in the Celtic Sea until 1980 at least.
    • Herring fisheries on the south and South-west coasts 1972-73

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1972)
      The 1972/73 winter herring fishery off the south coast began in the week ending 4 November 1972 and ended on 17 February 1973. The total landings at the ports of Dunmore East and Cobh amounted to 109,301 crans which was slightly short of the record catch of 110,816 crans made in the 1970/71 season. This represents an increase of 29,509 crans on the figure for the 1971/72 season. Eighty three boats, the same number as in 1971/72, took part in the fishery and landings were made on 80 days out of a possible 92. The introduction of a quota system which restricted catches for periods before and after Christmas undoubtedly contributed to the total catch being lower than it could have been.
    • The herring fisheries on the South and South-West coasts 1977-78

      Molloy, J (Department of Agriculture and Fisheries (Fisheries Division), 1978)
      Herring fishing off the south coast, in that area now commonly known as the Celtic Sea, was prohibited during most of the year commencing 1 April 1977. In spite of this, however, nearly 3,000 tans of adult herring are believed to have been taken, mainly by Irish and Dutch vessels. Scientific investigations and the results obtained from a trawling survey carried out from September 1977 to January 1978 indicated that the spawning stock is still in a very depleted condition. Recruitment of young herring to the adults stocks during the last three years has been critically low and because the adult stock size is now estimated to be only 10,000 tons a continuation of the existing ban on fishing must be envisaged for some time. The fishery off the south west coast in 1977, showed an increase in landings largely due to increased catches in November off Fenit, Co Kerry.
    • 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 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 investigations on the North West and West coasts 1975-76

      Molloy, J; Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1976)
      The herring fisheries off the northwest and west coasts during 1975 and 1976 are reviewed. Details are given about value of the fishery off the Donegal, Mayo and Galway coasts in recent years. Scientific examinations show that there has been a decline in stock size in the area, chiefly due to poor recruitment of young herring. The question of management of the fishery is also discussed in view of the increased catches by continental fleets fishing in the area.
    • Herring tagging experiments around Ireland, 1991

      Molloy, J; Barnwall, E; Morrison, J (Department of the Marine, 1993-05)
      The assessment and management of the herring fisheries around Ireland assumes that there are three distinct and separate populations. The management units are based on ICES Areas which, however, are not based on the distribution of the stocks and which do not take into account the mixing that takes place between the different stocks. In July 1992 a herring tagging experiment was carried out, designed to provided information on the migration of the herring around Ireland which would be useful in establishing more realistic management units. In the experiment over 20,000 herring were tagged and liberated - 10,000 southwest of the Isle of Man and 10,000 in Broadhaven Bay. Over 450 tagged fish have been recovered to date and the results suggested considerable movement of herring between the different management units. There appears to be a major link between the Irish Sea stocks and the part of the Celtic Sea stock that spawns off the south east coast of Ireland. A small number of fish tagged off the Mayo coast migrated south to the coast of Kerry. The mixing of these stocks should be taken into account when the various stocks are assessed and when the annual TAC's are estimated.
    • Herrring Investigations on the North-West and West coasts 1976

      Molloy, J; Kennedy, T D (Department of Agriculture and Fisheries (Fisheries Division), 1977)
      The herring fisheries off Donegal, Mayo and Galway in 1976 are reviewed. A serious decline in catches, particularly in the Donegal fishery, took place but this was compensated for by increased prices. The decline in catches is caused mainly by a decrease in stock size, because the recruitment of young herring in recent years has not compensated for the amounts removed by fishing. To minimise the dangers of poor recruitment it would be unwise to allow any fishing to develop on young immature herring in the area. The total international catch off Galway increased considerably in 1976, largely due to increased Dutch effort. International catch restrictions on the total catch are likely to be even more severe in future years.
    • Preliminary Investigations of the Sprat stocks off the South coast of Ireland

      Molloy, J; Bhatnagar, K (Department of Agriculture and Fisheries (Fisheries Division), 1977)
      The development of a new fishery for sprat off the south coast is reviewed. The fishery during 1976 and 1977 produced over 1,600 tons of sprat, valued at over £92,000. The quality of sprat landed was excellent throughout the fishing period. While it is difficult to estimate the size of the stock in the area, it would appear that landings could be substantially increased. This, together with the quality of the sprat, could make this fishery a valuable alternative to the Celtic Sea herring fishery.
    • Some comments on the management of the Irish mackerel fishery

      Molloy, J (Department of Fisheries and Forestry (Trade and Information Section), 1981)
      The total Irish catch of mackerel has increased dramatically in recent years and has risen from about 1000 tonnes in 1970/71 to approximately 50 000 tonnes in 1980/81. The total international catch taken by all countries in the ICES division VI, VII and VIII has also increased dramatically in the same period and has risen from 104,000 tonnes in 1970 to 604,000 tonnes in 1980. In 1980 mackerel contributed 40% of the total weight of the Irish wetfish catch and about 18% of the total value (based on the official statistics). Fishermen and processors have, in recent years, invested heavily in new vessels and in processing facilities, on the assumption of a continuation or even possible expansion of the recent high levels of mackerel catches. At the same time it is realized that pelagic fisheries such as herring and mackerel are liable to produce extremely erratic yields when intensively fished and there is always the danger of a sudden collapse of the fishery as has happened in many of our herring stocks. It is therefore important that those engaged in the mackerel fishery should be aware of the latest information relating to the assessment of the mackerel stock and also of the objectives as to how the stock should be managed.
    • 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.
    • 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.