Nest site selection and spawning by captive bred Atlantic salmon,Salmo salar, in a natural stream

摘要

The authors examined the physical habitat of nest sites chosen by hatchery Atlantic salmon, Salmo salar, in a recovery program for this extirpated species in Lake Ontario, Canada. The sites used by these captive bred fish were compared to a set of random locations in a wide range of available habitats. Compared to random locations in the stream, the nest sites chosen were lower in the relative abundance of sediment size classes that are detrimental to embryo and juvenile survival. In addition, the process of nest construction by these captive bred fish further reduced the proportions of these detrimental sediments. Although captive breeding may have changed some aspects of the nest site selection and construction behaviour, it has not caused a complete loss of major alteration of the trait and thus does not preclude hatchery fish from restoration or reintroduction programs.