Surveys for herring larvae off the northwest and west coasts of Ireland in 1982 and 1983

This Leaflet describes the methods used in sampling and gives the results of the 1982 and 1983 surveys in a series of maps showing the distribution of the young larvae. Sampling took place at fortnightly intervals and recorded the numbers of larvae in three size groups. The area of operation extended from Inishowen Head to Loop Head and thus includes the entire new assessment area for this herring stock. It was first surveyed for herring larvae in 1981 (see Fisheries Leaflet 117). As in1981, these surveys showed spawning to move progressively southwards during the season in October and November. There are three main spawning areas: the north Donegal coast, the west coast of Donegal and the west coast of Mayo. Larval abundance was over 10% higher in 1983 than in 1982. When the survey has been in progress for a few more years it will be possible to make an improved annual assessment of the herring stock in the region. This can be used by management to ensure that the fishery is exploited to the fullest extent without risk of damage to the stocks in the future