| Popis: |
An experiment was undertaken, using acoustic telemetry, to compare the survival and migratory timing of Salmo salar L. smolts sampled, under optimal conditions, in a traditional fixed Wolf trap against a sample of rod-caught fish captured using a sensitive angling technique. No significant difference was evident in survival with 83% of both samples detected in the river outflow, 67% of the trap and 76% of the rod samples were detected in coastal waters and finally 43% of the trap and 35% of the rod samples were detected on an offshore array c. 50 km from the river outlet. No significant difference was evident in the time taken for trap- and rod-sampled fish to reach either the river outflow, coastal or offshore waters. Angling, if undertaken sensitively, can provide an effective, resource-efficient and ethically justifiable sampling tool for juvenile salmonid age classes. |
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