PROTECTING & IMPROVING
THE TAY DISTRICT KELT RECONDITIONING PROJECT
The Kelt Reconditioning Project is the largest initiative that the Board is involved in at present, by far.
This ground breaking project was originally established in the early 1990s by Marine Scotland Science. They set up a unique facility at Almondbank in which fed captive adult salmon which had spawned (kelts) were successfully encouraged to start feeding again while still in freshwater. These were fish which would otherwise have died. Instead, they survive, grow and produce eggs repeatedly over a number of years. However, in early 2011, Marine Scotland Science decided to close this facility, which is unique in Europe (kelt reconditioning was only one of a number of research projects being conducted at Almondbank). Therefore, in order to prevent the loss of the Kelt Reconditioning Project, on 1 April 2011, the Board, who had been involved in the project since the outset, took over the former Marine Scotland Science experimental fish rearing unit at Almondbank. Over the remainder of 2011, the Board occupied the facility on a trial basis. It was decided on the basis of that experience that the Board should not only continue to try to run this facility, but to expand it now that it was under the Board's control. It was decided that this facility should become the central part of the Board’s hatchery policy.
Mature spring salmon are caught in headwater areas just before they spawn by Board staff and are stripped by MSS staff. If the fish had been left in the river they would have spawned but thereafter would have been very lucky indeed to survive to spawn a second time. However, the MSS staff perfected a technique whereby the spent “kelts” are coaxed to recommence feeding while still in captivity, and in freshwater. These fish then regain weight and condition and mature to produce eggs again. Most females survive long enough to produce eggs over several successive years. The record is with Dolly, our champion hen fish, who produced eggs for nine years.
In this way it has proved possible to produce significant numbers of eggs from adult spring salmon of known tributary of origin which would otherwise have been dead. This means that eggs can be obtained from small special populations from which eggs could not otherwise be removed.
In recent years this project has yielded approximately 750,000 spring salmon eggs each year. These eggs have proved particularly valuable in allowing us to conduct experimental stocking in a number of areas where juvenile salmon numbers were very low.
One such example was the upper River Lochay where the stocking resulted in a marked increase in juvenile numbers and proved that the river had previously been greatly understocked, probably as a result of access problems for adult fish.
Another example is the Cononish, the name given to the headwaters of the River Dochart. Up to a few years ago juvenile salmon densities in the Cononish were very low, for reasons which are still not completely clear However, as a result of the stocking the number of juvenile salmon in the Cononish has increased markedly. Without kelt reconditioning we could never have risked removing broodstock from the river to stock such a risky area as the Cononish.
In order to ensure that genetic diversity is maximized, fish to be stripped are genetically typed by Landcatch Natural Selection from Alloa. This ensures that crosses will not be made between closely related individuals, for example, although it is not thought this should have been a major issue.