A survey of ovarian maturation in a population of Aristeus antennatus (Crustacea: Decapoda)

Ovaries of the shrimp A. antennatus, as observed in other crustaceans, show several colour changes during their life-cycle that are related to growth and maturation of oocytes. In prawns, transparency of cuticles facilitates examination of gonads with the naked-eye. From colour recognition, one can assess ovarian development in a population using fresh material. Because results obtained by this method can be biased by interference with other pigments, histological examination of ovarian maturation is highly desirable. Freshly caught females from western Sicily were examined during the course of one year, either aboard a fishing-vessel or preserved material was examined under the light microscope. Comparison of the results from both "in the field" and by histological methods revealed an annual cycle of ovarian development according to a scale of colour-change. In summary, occurrence of a peak in oocyte growth was demonstrated during the summer months.