Abstract

Apart from the availability of suitable food, crayfish density and number of shelters are considered among the most important factors affecting the production in an intensive and/or semi-intensive culture. The effect of crayfish density and of the number of shelters on the activity of one-year-old signal crayfish (Pacifastacus leniusculus) were observed in this experiment. Combinations of densities (18.8, 28.1 and 34.4 ind. m^-2) and ratios of crayfish to the number of shelters (1:1, 1:1.5 and 1:2) were tested. Only one difference in crayfish activity was found. Crayfish at the highest density and at 1:1 crayfish/shelter ratio restricted their activity and they probably protected their shelters. The daily activity of one-year-old and of adult signal crayfish was investigated in a three-day continuous experiment in fibreglass tanks. Most one-year-old crayfish were active between 1900 and 0300 and the lowest activity was registered between 0600 and 1100. The adult crayfish were active between 1900 and 0200, whilst the lowest activity was noticed between 0500 and 1100.

Supplemental Documents

• There are no supplementary documents for this article

Cited By

Citations: