Anti-predator response of Haliotis tuberculata is modified after only one generation of domestication

Abstract

Domestication of Haliotis tuberculata has only recently begun. During the process, we expect that behavioural and physiological traits may evolve to become more adapted to their captive environment. These modifications may result from intentional selection of production traits or unconscious and unintentional selection due to conditions experienced in the farm environment. To study this process at the earliest stage, the progeny of 3 different broodstocks obtained from wild parents, selected farmed abalone and randomly sampled farmed abalone, were studied. After rearing for 16 mo in separate tanks, offspring from the 3 progenies were placed together in sea cages at the same density. After 3 yr, behavioural traits were studied, and the immune status after a stress situation was assessed. Mortality and growth were also recorded. In spite of the fact that no significant differences were observed in survival, growth or immune status traits between the 3 progenies, less progeny from the selected broodstock performed the complete sequence of anti-predation behaviour, and they took more time to reach their hides compared to the wild progeny. In addition, the shell colours of the selected progeny were more orange and had more stripes compared to the brown-green colour of the wild progeny. Progeny of randomly sampled broodstock showed intermediate responses between those of wild and selected progeny. Our results suggest that associated behavioural trade-offs can take place after only one generation of selection to improve growth. This should be taken into consideration when using selected stocks for ranching or population enhancement programs.