Parr dispersal between streams via a marine environment: A novel mechanism behind straying for anadromous brown trout?

Otolith Sr:Ca profiles demonstrated that juvenile anadromous brown trout (ABT) Salmo trutta may descend to the brackish waters of the Baltic Sea from their natal streams as parr or fry and then migrate into non-natal streams before transforming into smolt. To our knowledge, no such published documentation exists for ABT. The ecological significance of this life-history strategy is presently not clear. However, stream shifting through the marine environment should to be considered with regard to stock management and the assessment and restoration of salmonid populations and their potential habitats.