Mother-offspring relationships in the red-claw crayfish Cherax quadricarinatus

Abstract

Mother-offspring relationships were studied in the red-claw crayfish Cherax quadricarinatus during 3 phases: 'egg-carrying,' 'hatching,' and 'release.' The maternal behavior of 16 females and the dispersal of their young were monitored with a video camera in small- and large-sized aquaria. Time allocated to locomotion, aeration, and cleaning was computed for each phase. During the release phase there was an increase in mobility and a reduction in time devoted to fanning as compared to the egg-carrying and hatching phases. A significant negative linear regression was found between the number of juveniles on the mother and days since release. Mother-offspring association was considerably prolonged under conditions of limited space, resulting in a delay in the next breeding cycle of the female. The implications of this study for the commercial production of red-claw crayfish are discussed.