Observations on swim bladder stress syndrome in Arctic charr (Salvelinus alpinus), induced by inadequate water depth

In two separate experiments, juvenile Arctic charr (Salvelinus alpinus) were held at three different water depths (12, 24 and 37 cm) and at three different stocking densities (10, 50 and 100 kg/m³). Mortalities from swim bladder stress syndrome (SBSS) were noted over 2 months. Low water depth caused high mortality while stocking density did not induce the stress syndrome to any notable degree. An analysis of catecholamines in the blood plasma of a small number of fish indicated elevated dopamine levels in stressed fish.