Apparent Sunburn of Juvenile Paddlefish

Abstract

Abstract Juvenile paddlefish (Polyodon spathula) transferred to outdoor raceways at the National Fish Hatchery and Technology Center, San Marcos, Texas, exhibited dorsal skin lesions characteristic of sunburn within 1 week. These fish were assigned to one of three classifications: normal, burned, or curved (curved rostrum), depending upon the severity of the lesions. Approximately equal numbers of fish from each classification were stocked into a raceway in two compartments. One section remained uncovered and received full sunlight while the other was covered and received reduced sunlight for 51 d. Survival of the covered and uncovered fish was 87% and 55%, respectively. Many of the covered fish returned to the normal condition.