Efficacy of releasing captive reared broodstock into an imperilled wild Atlantic salmon population as a recovery strategy
Abstract:The strategy of releasing captive reared adult Atlantic salmon Salmo salar into the Magaguadavic River, New Brunswick, Canada, to spawn, was not an effective tool for rebuilding a seriously depressed wild population. The fish were first generation progeny from wild parents, and had spent their entire lives in captivity in either sea or fresh water. No differences in movement or behaviour patterns were observed between freshwater and seawater reared groups. Fish released in the lower river early (35 to 80 days prior to the natural spawning period) moved into a lake low in the system, and most stayed there near the commercial hatchery where they had been reared from egg to smolt. During the spawning season, none moved to the upper river reaches where most spawning habitat exists. Most broodstock released in the upper river reaches near the time of spawning stayed there during the spawning period. The following year few to no Atlantic salmon fry were found, and most appeared not to be offspring of released adults.
Document Type: Regular Paper
Affiliations: 1: Atlantic Salmon Federation, P. O. Box 5200, St Andrews, New Brunswick, E5B 3S8, Canada and 2: Department of Fisheries & Oceans, Bedford Institute of Oceanography, 1 Challenger Drive, Dartmouth, NS, B2Y 4A2, Canada
Publication date: December 1, 2004