IT IS now 10 months since Marine Science Scotland (MSS), based at their offices in Ferryden, started radio tagging of Salmon at Usan just south of the town of Montrose.
The basis of the exercise was to track the spring run salmon on the South Esk up river and to find the areas of the river where they spawned and consequently to see if improvements could be made to their habitat.
It was also hoped that an understanding of the make up of what was recognised as a mixed stock fishery really was. A mixed stock fishery, such as that at Usan and Lunan Bay, is made up of salmon returning to their rivers of birth and in this case from several east coast rivers.
Tracking stations were set up on the South Esk at various places from the sea to the Prosen junction and further up into Glen Clova. Secondly a few stations were placed in the North Esk, while the Tay and Dee Fishery boards, who had there own equipment, tuned them to pick up Usan fish.
Early reports showed fish in both the South and North Esk and also in the river Tay. It was found that many fish passed upstream and quite quickly returned to the sea and there was no way of identifying them if they did return.
It was then accepted that the Usan Fishery was indeed a mixed stock fishery and that it was intercepting fish from at least three river systems.
In recent weeks the MSS have flown the main stem of the River Dee by helicopter and have found around eight salmon throughout the river, but there may be more as the spawning tributaries were not checked.
This news was not welcomed by anglers from the Dee as they were unaware that fish taken in Lunan Bay were from their river stock.
Only last week a similar flight was taken on the River Don and radio tagged salmon were found high up the main stem of it also. Again the main spawning tributaries were not checked and on this river system this is a high proportion of the spawning redds.
Some of the tagged salmon were re-caught by the Lunan bay nets and some have just disappeared.
It is now becoming apparent that over 60 per cent of the tagged fish are from stocks other than the South Esk and this I find very disturbing.
It has always been thought that the bulk of salmon caught there were on the way to the South Esk and this it seems is far from the truth. The vast majority of people on the South Esk are very concerned at the stock level of salmon in the river and now that we can deduce that roughly two salmon in six caught in Lunan Bay are indeed on their way to the river, it concerns me very much more.
MSS in their concern that their immediate results within the South Esk have been largely insufficient are to net salmon already in the river as of next spring and it is hoped that these fish will proceed upriver and that the areas favoured by these early running fish will be better understood.
This study has brought out results which were suspected but never before proven and it is to be hoped that next year will bring more success to this very interesting scientific work.