By G.W. Smith
Fisheries Research, Volume 10, Issues 1-2 Fisheries Research and the Atlantic Salmon - Assessment and Regulation in a Time of Change, December 1990, Pages 73-91, ISSN 0165-7836, DOI: 10.1016/0165-7836(90)90016-O.

Daily catches from the net and coble and fixed-engine fisheries at the mouth of the Aberdeenshire Dee have been analysed together with mean daily river flow rates for the years 1973-1986 inclusive. There was no indication that flow was a significant factor in determining the size of the net catch from one year to the next.
In most years, the logarithms of daily flow and catch from both fisheries were significantly correlated over the netting season as a whole. This may have been the result of a coincidence of independent seasonal trends in flow and catch rather than a direct effect of river flow on net catches of salmon.
Catches in the net and coble fishery were not uniformly high on days of low flow. Indeed, a wide range of catches was taken at low flows throughout the netting season. Low summer flows were not associated with higher than average net catches. Indeed, only during April were mean daily catches, associated with a restricted range of flow rates, significantly higher than mean daily catches calculated for the month as a whole. Such flows occurred at river flows between Q30 and Q35 for April, and the increase in catch accounted for 4.3% of the net and coble catch in April, and 0.5% of all net and coble catches over the study period.

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