Interim Semi Natural Rearing {SNR] Project Report

An Interim Report into results from the semi natural rearing of salmon smolts as part of a long term stocking strategy for the Wye.

Abstract

Atlantic salmon parr (Salmo salar) obtained from the NRW Hatchery at Cynrig near Brecon for Wye broodstock were reared in natural ponds along the river catchment. Parr placed in the ponds were able to complete their life cycle to smolting feeding on a diet of natural aquatic insects and invertebrates. Average release weights at smolting were approximately 25% heavier than the average S1 smolt grown at Cynrig hatchery. Parr to smolt survival in these semi natural rearing ponds was 67% compared with an expected 1 to 12% wild survival. Returning adults were monitored for fin clipping on 7 beats that caught 30.7% of 2016 season catch. Interim results suggest an adult return of stocked fish in 2016 in the range of 373 to 410 adults.

See full report at: SNR-Interim-Report-2016_v5