Fish stock assessments form a significant proportion of all freshwater monitoring conducted by the Loughs Agency.
Traditionally this would have consisted of annual catchment wide electrofishing surveys conducted during the summer months.
The electrofishing survey results provide a snap shot of freshwater production for Atlantic salmon and trout fry with the opportunity to record other age classes of salmon and trout and other species presence and absence.
The semi quantitative method used by the Loughs Agency was developed by scientists at the River Bush Salmon Research Station in Bushmills and is now widely used throughout Ireland the United Kingdom and elsewhere. Additional information including habitat quality and vegetation cover is recorded at the time of survey.
Approximately 500 semi quantitative electrofishing stations are surveyed annually in the Foyle and Carlingford areas. Results are displayed in the annual series of catchment status reports which can be downloaded from this website.
In recent years the Loughs Agency freshwater fish stock assessment programme has grown to include river and lake fish monitoring for various purposes including for inclusion in surface water classifications under the European Union Water Framework Directive, for development purposes and for meeting other obligations.
Many freshwater fish stock assessment methods are utilised by the Loughs Agency including semi quantitative and quantitative electrofishing, fyke netting, seine netting, gill netting, fish counters, analysis of catch records, radio tracking, use of Rotary Screw Traps, mark recapture experiments, Coded Wire Tagging and redd counting.
Depending on the fishery management question appropriate fish stock assessments can be designed targeting specific fish species and life stages to facilitate appropriate data collection. The information collected during any fish stock assessment is then collated in a report and provided to managers for consideration as part of the fishery management process.
It should be highlighted that it is an offence to deploy equipment for the purpose of fish capture without being in possession of the appropriate permit/license. If you require further information on the process for applying for a permit/license please contact the Loughs Agency using the details provided on this website. Failure to do so may result in the seizure of equipment and prosecution.