Laboratory observations on emergent patterns of juvenile Atlantic salmon, Salmo salar, relative to sediment loadings of test substrate

Effects of various loadings of a test gravel incubation substrate (32- to >4-mm pebble) with a single sediment mix (<0.25- to 4-mm sand) were examined in vertical flow incubators at a constant temperature (9.9 °C) and flow rate (200 mL min −1 ). Mean survival (75%) from ova burial to juvenile emergence was not influenced significantly by different sediment loadings. However, time to first and median emergence, duration of emergence, stage of development at emergence, and within-substrate behaviour were each correlated positively with mean particle size (r ≥ 0.72) and negatively with sediment loading rates (r ≥ −0.68).