Harpaz, S., Department of Aquaculture, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel, Department of Aquaculture, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
Clark, L., US Department of Agriculture, Animal Plant Health Inspection Service, National Wildlife Research Center, Fort Collins, CO, United States

The effects of adding the nonlethal bird repellent methyl anthranilate (MA), at levels of 100 and 1000 mg kg-1, to fish feed on the bioaccumulation and growth of juvenile (10 g) hybrid striped bass (Morone chrysops×M. saxatilis) and juvenile (1 g) African cichlid fish Aulonocara jacobfreibergi were investigated under laboratory conditions. The bird repellent did not have any effect on the fish growth or survival over a period of 6 weeks. MA residues at low levels of 11.2±2.6 μg g-1 were found in lipophilic tissues (liver) of MA-fed fish. Control fish, which had no MA added to their diet, had a much lower level of 0.6±0.3 μg g -1 MA in their liver. Fish muscle was found to contain negligible MA residues, while the outer body surface mucus did not contain any MA. Following a 6-week depuration period, during which the previously MA-fed hybrid striped bass were fed a feed to which no MA was added, the levels of MA residues detected were reduced by one order of magnitude. © 2005 Blackwell Publishing Ltd.