Abstract

In order to obtain young crayfish for stocking, the Institute of Conservation of Nature (ICONA) of the Ministery of Agriculture, has built the astaciculture centrum 'El Chaparrillo' in the province of Ciudad Real (Spain), which is a typical area known for its excellent conditions for crayfish. The astacifactory includes a place for eclosion and breeding, raceways for rebreeding, raceways for reproductors, ponds for culture of algae and daphnia, as well as aquariumn and laboratory, supplied with water pumped from a well of excellent conditions for the crayfish biology. The experiment has been carried out starting with 24,000 wild Astacus pallipes of different ages and sexes. The feeding was made with fitoplancton and zooplancton, typical in the stagnated waters, and supplemented with half boiled potatoes, watercress, nettles, carrots and low class fish. The results obtained from July 1976 to May 1978, have been the following: Copulation period: October - November. Eggs per female: 50 to 60. Eggs eclosion period: 1st April to 15th May. Births: 80%. Moulting period: End August to end October, and March to May. Number of moults in the reproductors: 1 - 2. Number of moults in the juveniles, per year: 5 - 6. Length and weight when 2 months olds: 1.5 to 2 cm. and 0.26 grs. Length and weight after one year: 4.5 to 5 cm. and 2.7 grs. Mortality in adults: 13%. Mortality in juveniles per year: 40 to 60%. Incidents: During the two years of this experiment, no pathologic processes have been observed, be they infectious or parasitic. The high mortality of juveniles was produced especially during the three first months of live, as a consequence of feeding defects and canibalism.

Supplemental Documents

• There are no supplementary documents for this article

Cited By

Citations: