Effects of food supply on the growth and survival of the common shrimp, Crangon crangon (Linnaeus, 1758) (Decapoda, Caridea)

The common shrimp, Crangon crangon (Linnaeus, 1758) was reared in the labor atory under controlled conditions (15 degrees C; 34 parts per thousand; 12/ 12 LD), using natural food: frozen muscle of Nephrops and prawns. The effec ts of food supply (fed each day and every fifth day) on growth were investi gated for females and males. Each shrimp was maintained individually, the i nstar size was determined from exuviae, and the intermoult period was recor ded. Survival was higher in both sexes when fed daily than when fed less frequen tly. In both sexes a food reduction both lengthened the duration of the int ermoult period and reduced the moult increment. Consequently, this led to a lower growth rate with reduced feeding. The effects were greater on increm ent in both sexes, and female growth was more affected in both components. The relative: importance of extended intermoults and reduced increments in limiting the growth of crustaceans is discussed.