As part of a project being undertaken by the Tweed Trout & Grayling Initiative it is hoped that anglers can be recruited to collect scales from trout.

Reading scales from trout, grayling and salmon is a vital tool in fisheries management. Each scale contains a record of fish growth that is similar to tree rings (but is much more complicated). By studying the growth information on scales it is possible to work out fish age (by noting the number of bands of slower winter growth and the date of capture); growth rates (by comparing the length of the fish to the age); whether or not the fish has been to sea or not (fast growth is recorded on fish that have been to sea) and in some cases the number of times the fish has spawned (by counting the “spawning marks” on the scales of fish that have spawned).

On the Tweed we have the additional benefit of having information from trout scale studies that were carried out in the 1970’s. The Initiative aims to compare modern trout growth rates with the growth rate recorded in the 70’s. This will provide useful information on past and present food supplies and competition for food.

If you would like to help the Initiative by collecting scales from wild Brown Trout caught within the Tweed system follow the instructions below. Scales should only be taken from trout that are being taken home for the pot and scale packets can be requested from:-

kgalt@tweedfoundation.org.uk

 To see how to take scales please download the file TROUT SCALE ARTICLE.pdf (35kb)