Sorting eggs from plankton samples, identification of eggs to species and the staging of those eggs remains one of the key areas in the execution of the mackerel and horse mackerel egg surveys. In the context of these surveys, fecundity estimation is very important for conversion of egg production to biomass. Fecundity estimation is carried out using histological methods. Both processes are carried out by a number of different operators in many different countries and it is vital that the process be standardized. During the workshops validated eggs are staged and identified and fecundity and atresia samples analysed.
The workshop is divided into two different parts, one focusing on egg sorting, identification and staging and one for fecundity and atresia estimation. The workshops are held in the year prior to the triennial mackerel and horse mackerel egg survey. The workshop aims at using validated eggs (eggs from fertilization experiments) but also includes eggs from samples taken during the last egg survey. Next to identifying the key species of the survey, the workshop also includes fish species that have similar eggs and occur in the sampling area. During the workshops new techniques and developments are discussed and incorporated in the analysis of eggs and fecundity in the coming survey.
Horse mackerel eggs