Effects of hypoxia on food consumption and growth of juvenile striped bass (Morone saxatilis)

Hypoxia and an apparent temperature-oxygen squeeze have been reported for many coastal ecosystems and reservoirs with striped bass Morone saxatilis. Studies have identified limits of dissolved oxygen (DO) for this species, but interactive effects of concurrent temperatures and low DO have not been addressed. We conducted laboratory experiments on juvenile (23 g) striped bass consumption and growth in a 4x3 factorial design using 4 temperatures (20, 23, 27, and 30 degrees C and 3 DO levels (2 mg L-1, 4 mg L-1 and saturation). Temperature did not affect striped bass food consumption, but consumption increased with increased DO levels. Growth was related to DO as well as to the interaction between temperature and DO, and striped bass growth was strongly curtailed below 4 mg L-1 DO. Laboratory results were used to derive an equation to apply the effects of environmental DO level to striped bass bioenergetics models. Overall results should be useful to predict changes in striped bass habitat quality in response to changes in hypoxic conditions. (C) 2009 Elsevier B.V. All rights reserved.