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Title: The Effect of Atrazine Exposure on the Timing of Salmon (Salmo salar L.) Smolt Emigration
Author: A. Moore
Author: G.A. Fewings
Document Type: Monograph
In 1992 and 1993, atrazine was one of the five pesticides most frequently present in both ground and surface water at levels in excess of the Maximum Admissible Concentration (MAC) 0.1 micron g/ litre imposed by the Water Act 1991 (National Rivers Authority, 1995). This study examined the impact on run-timing in groups of hatchery reared Atlantic salmon smolts exposed to different concentrations of pesticide prior to release in the River Test, southern England. Fish were identified using passive integrated transponding tags and exposed to the pesticide for 10 days prior to release. Fish were recaptured using a smolt trap, which was operated continuously during the trapping period. As only one of the treated fish were recaptured no conclusions could be drawn regarding the effects of pesticide exposure. Analysis of the gill Na.+ K+ ATPase activity indicated that both treated groups of fish had significantly (p<0.05) lower Na+ K+ ATPase activity than the control group. It was therefore suggested that exposure to even 5 micron grams per litre of Atrazine may have reduced the ability of the fish to hypoosmoregulate and therefore survive the transition from fresh to saltwater. This study was not able to provide further evidence to support or contradict the hypothesis that exposure to atrazine modified the migratory behaviour of salmon parr of smolt age and size.
Publisher: Environment Agency
Publication Date: 2003
Publication Place: Bristol
Subject Keywords: AtrazinePesticidesSalmonReproductionMigrationJuvenilesSurvivalSurface waterGroundwaterTelemetryWater quality
Geographic Keywords: EnglandTest (river, Hampshire)Test and Itchen catchment
Taxonomic Keywords: SalmonidaeSalmo salar
Extent: 10; + appendices
Total file downloads: 295

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