Two half-day sessions were held by The Tweed Foundation recently to show Tweed boatmen what is entailed in the monitoring work that the organisation undertakes every year for juvenile Salmon and Trout.  Those that took part were interested and surprised to see the high numbers of juvenile Salmon and Trout that can be captured in a small area of river in a short three-minute sample.

Tweed boatmen watch as two of the Foundation's biologists electro-fish on the Leader Water

Most people who have not come across "electro-fishing" before imagine all sorts of horrific things happening  ........especially when biologists confirm that, as the title suggests, it really does mean mixing electricity and water!

The process is, in fact, entirely harmless to fish (and humans!) and involves passing a mild electric current through the water which 'draws' the fish towards the source of the current allowing biologists to scoop up the fish in hand nets.  The fish are merely stunned and recover almost immediately to swim away unharmed.  Each fish is measured, species recorded and, in some instances, scales taken (to allow ageing) before being returned to the water.

The other end of the scale from what they're used to!
Dr Campbell shows Tweed boatmen the size of fish that will ultimately become Tweed's fishing stock

Over time this allows The Foundation to build up a database of the population structure and numbers of juvenile fish in locations all over the Tweed catchment.  The Foundation has over 500 electro-fishing sites which are visited on a three-year rotation, allowing habitat problems or any changes in population to be quickly pinpointed and remedied, where possible.

To those who have not witnessed the process before, it is fascinating to see that what appears to be an empty area of water is in fact alive with fish.... and a heartening sight to learn that our headwaters are filled to capacity with healthy, juvenile Salmon and Trout.

If you would like to see electro-fishing first-hand, please contact The Tweed Foundation. This summer The Foundation's electro-fishing monitoring programme will be concentrated on the Rivers Til and Teviot systems.

Tel: 01896 848271

Individual members of the public are welcome to come along on a summer surveying day, by arrangement.  If there is sufficient interest, The Foundation is very happy to organise an open day to show larger groups what is entailed and what the information is used for.