Rearing Performance of Atlantic Salmon Grown in Circular Tanks with Vertically-Suspended Environmental Enrichment

摘要

Environmental enrichment is the incorporation of materials into hatchery tanks to simulate a more natural rearing environment. This study investigated the use of a vertically-suspended plastic conduit array as enrichment in 3.63 m circular tanks during Atlantic salmon ( Salmo salar ) rearing. After 168 days, feed conversion ratio was significantly improved for salmon reared in tanks with enrichment compared to the barren control tanks. Final tank weights and weight gain were not significantly different, although the difference in mean gain of 182.0 kg in the enriched tanks compared to 162.9 kg in the control tanks approached significance. There were no significant differences in individual fish length, weight, or condition factor between the treatments, likely because of large variances in body size due to sexual dimorphism and small sample sizes. The suspended array did not interfere with the hydraulic self-cleaning of the circular tanks. The results of this study support the use of vertically-suspended structures to improve the hatchery rearing performance of Atlantic salmon in circular tanks.