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The structure of trout populations : inventory of migratory types by pigment analysis - SF0104

R&D Summary Objectives:- Establish whether natural variations in caratenoid pigmentation in brown trout can be used to determine migratory history for different stocks of brown trout. Key customer purpose:- Through a better understanding of the structure of migratory and non-migratory populations of brown trout, MAFF will be able to identify the cause of recent stock declines and thus implement effective management procedures.
The general objectives of the study are twofold: to advance our ability to describe genetic population structure in trout, coupling demographic with genetic analyses (a current SOAFD project), and to facilitate inventory by life-history type for the management of stream populations of trout. The present proposal is for an enabling study and its immediate objectives are therefore modest. Specific objectives are limited to establishing the likely usefulness of carotenoid pigment variation 1) as a measure of maternal feeding location in trout and 2) - in recently emerged trout progeny - as a measure of maternal pigmentation. To achieve this a quantitative HPLC method will be established to examine carotenoid pigments in organic solvent extracts of trout tissues (including ovary) and of eggs, alevins and fry derived from females obtained from a number of sources. It is expected that 10-12 carotenoid components will resolve sufficiently to be considered as discriminators.
Time-Scale and Cost
From: 1993

To: 1994

Cost: £11,930
Contractor / Funded Organisations
University - Aberdeen
Fields of Study
Freshwater Fisheries