• The age Distribution of the Herring Stocks around the Irish Coast during 1993

      Barnwall, E.; Molloy, J. (1994)
      The age distribution of stocks is usually considered as an indication of how healthy a stock may be. In general stocks which are lightly exploited will contain a much larger proportion of older fish than a stock which is heavily exploited. A stock which is heavily exploited will probably be dependent on one year class which will recruit to the fishery and which will immediately be subjected to fishing effort. Obviously in such a fishery failure of recruitment or poor recruitment will have drastic effect on the catches. Herrings can be aged accurately until are about 10 years old and generally recruit to the adult stocks during their third year. During this year, the majority of fish will spawn for the first time.