Selected clinicopathological features were compared between resting striped bass Morone saxatilis and palmetto bass (striped bass female x white bass M. chrysops male) and fish subjected to an acute (2-h-long) confinement stress. The taxa differed significantly in resting plasma lysozyme activities and leukocyte responses to mitogen stimulation. Confined fish of both taxa showed similar elevations in plasma osmolality, potassium. anion gap, creatinine, and glucose, suggesting a shock response. However, striped bass displayed slightly more severe perturbations, including elevated albumin and total protein, that indicated hemoconcentration. At least some of the intertaxon differences may have been associated with the greater ability of palmetto bass to adapt to culture conditions.