THE USE OF BEHAVIORAL OBSERVATIONS IN THE LARVICULTURE OF COLD-WATER MARINE FISH

The use of behavioural observations on marine fish larvae has a long h istory and has added considerable depth to our understanding of the ec ological adaptations of larval fish. In marine fish larviculture we ar e trying to domesticate wild animals. Behavioural observation, in conj unction with growth and survival information, is a powerful tool for u nderstanding the behavioural adaptations of larvae. This paper reports on the results of experiments conducted on the first-feeding of two s pecies of marine larvae. Results of experiments carried out on lumpfis h (Cyclopterus lumpus) fed the same density of live prey in pulses (tw ice or three times/day) or continuously, demonstrated that growth and feeding behaviour was significantly higher in the pulse treatments. A second set of experiments was performed on weaning of Atlantic wolffis h (Anarhichas lupus) larvae. Live prey and pelleted food were offered to larvae from the onset of first-feeding. Observations on larvae indi cated that over the first few weeks, larvae fed mostly on live prey wi th some pellet feeding. This pattern changed as larvae grew and by eig ht weeks larvae fed mostly on pelleted feed. In this example, the beha viour of the larvae provided a schedule which could be used to wean wo lffish from live prey to pellet food. Using this information, improvem ents of the rearing protocols of these species may now be made. (C) 19 97 Published by Elsevier Science B.V.