TANK SIZE AFFECTS SWIMMING ACTIVITY OF ATLANTIC SALMON (Salmo salar)

摘要

The size of the aquaculture rearing units, both tanks and sea cages, has been increasing in recent years. The research related to farmed fish is still predominately done in smaller scale units, allowing for the reduction in number of experimental animals and reduced cost to achieve adequate experimental design. The change in tank scale in relation to the fish length could affect swimming activity and patterns, stress levels and energy dissipation. So far, the effects of tank scale on the activity ofreared fish are not well documented. The use of telemetry techniques have allowed for direct measurement of the activity levels of free-swimming fish (Cooke et al., 2000). The aim of this study was to investigate the effects of the experimental unit sizeon the swimming activity of Atlantic salmon, using acoustic acceleration transmitter tags (AccelTag; ThelmaBiotel, Trondheim, Norway). The experiment was designed to reflect typical changes in conditions when using large vs. small tanks in experiments.Hence, water turnover time was deliberately set to increase with scale (e.g. Davidson and Summerfelt, 2004).