Crisp, D.T. (1988) The effects of a sand layer upon swim-up success in UK salmonids. Ambleside, UK, Freshwater Biological Association, 30pp. (WIT/TO4OO9-5/2).
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There are two main ways in which gravel composition and changes therein arising from siltation, can influence the survival of young salmonids. First, the composition of the gravel will affect its permeability and, hence, may influence the survival of eggs and alevins through its effect upon the rate of supply of oxygen and the rate of removal of metabolic products. Second, the composition of the gravel may affect the ease, or otherwise, of emergence at the time of swim-up and alevins may become trapped in the gravel and perish. This aspect is the main concern of the present report. Experiments were conducted to examine the effects upon fry emergence of a sand layer deposited on the gravel surface. The study concludes that fry of brown trout and Atlantic salmon emerged through layers of sand up to 8 cm thick but the percentage emergence, even from the controls with no sand, was relatively low (5 - 68%). There was no firm evidence that the experimental treatments influenced percentage emergence, timing of emergence or weight of fry at the time of emergence.
|Item Type:||Monograph or Serial issue|
|Title:||The effects of a sand layer upon swim-up success in UK salmonids|
|Number of Pages:||30|
|Publisher:||Freshwater Biological Association|
|Place of Publication:||Ambleside, UK|
|Issuing Agency:||Freshwater Biological Association|
|Uncontrolled Keywords:||Rivers; Fry; Experimental data; Water currents; Fish; Developmental stages; Dissolved oxygen; England; Kielder Water Reservoir; Salmo trutta; Salmo salar|
|Depositing User:||Hardy B Schwamm|
|Date Deposited:||28 Apr 2011 18:32|
|Last Modified:||29 Sep 2011 17:12|
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