Fish Barrier Mitigation

Black rocks weirsART strive to improve fish access across the catchments through the removal or mitigation of barriers.  One of the greatest barriers to migration is man-made structures such as disused weirs, of which there are plenty in Ayrshire.

The Scotland & Northern Ireland Forum for Environmental Research (SNIFFER) barrier assessment is a relatively new method for assessing barrier porosity.  It has been developed to provide rapid, repeatable and quantifiable measurements, helping to prioritise the removal or mitigation of man-made structures that impede the migration of fish populations.  Results are easily auditable and the procedure consistently applicable.  It does not rely heavily on expert judgement which can be highly subjective and of varying accuracy depending of the surveyor’s degree of experience.  The method can be used for a full range of man-made and natural obstacles as well as the full range of species encountered in the UK.

Girvan dykes

The EU Water Framework Directive 2000/60/EC require that riparian owners mitigate the effect of barriers to migratory fish.  The best way of doing this is to fully remove the barrier.   By removing or mitigating barriers by the inclusion of fish passes etc., we are often able to open up great stretches of prime spawning habitat in upstream tributaries.

To date ART have installed fish passes in the Girvan Dykes at the lower end of the river, as well as installed small weirs below the Black Rocks Waterfall in Kilmarnock to increase the water depth and allow salmonids a greater plunge pool from which to leap, following the pool’s infill with concrete in the 1960’s.





Posted on

April 8, 2013