WINTER STRESS SYNDROME - AN IMPORTANT CONSIDERATION FOR HAZARD ASSESSMENT OF AQUATIC POLLUTANTS

Winter Stress Syndrome (WSS) is a condition of severe lipid depletion in fish brought on by external stressors in combination with normal re ductions in feeding and activity during cold weather, Fish can develop this syndrome in response to chemical stressors, such as water pollut ants, or biological stressors such as parasites, Substantial mortality can result, potentially changing year-class strength and population s tructure of the affected species and altering community-level ecologic al interactions. Aquatic contaminants should be evaluated in the conte xt of seasonal metabolic changes that normally occur in test organisms . WSS could be an important, but as yet unquantified, cause of mortali ty in many circumstances, Wastewater discharges may pose a greater tox ic threat to fish during winter than at other times of the year. A com prehensive protocol for aquatic hazard assessment should include testi ng for WSS. (C) 1996 Academic Press, Inc.