What We Do
The River Tweed is unique in many respects, but it is its location, straddling the Border between England and Scotland, that over the years has spurred the emergence of a very different approach to managing and protecting its fisheries. Tweed has traditionally been regarded and administered as a “Scottish” Salmon river, but with its estuary and a fifth of its catchment in England it was recognised, even from medieval times, that it needed separate legislation if it was to protect its fish stocks and fisheries in a concerted way. Managing whole river catchments as single entities is being heralded as the modern, enlightened approach to the successful management of wild fisheries but it is a working concept that has been around in the Borders for centuries.
The River Tweed Commission (RTC) was set up under private Acts of Parliament in the mid 1800s and still operates under many of the powers granted by that legislation. The Tweed Foundation is a charitable company founded with the purpose of providing objective, scientific information to allow informed decisions to be taken by managers. Information on the river, its environment, the fish and the economies of the fisheries have allowed work to greatest effect. The Tweed Foundation’s biological work plan is the Tweed Fisheries Management Plan which was first published in 1990 and is reviewed every five years. Each year the Trustees decide its current priorities; our current work includes:
Monitoring the distribution of juvenile fish stocks helps in identifying environmental problems and also understanding the physical conditions that determine the boundaries between areas populated by Trout and Salmon. The abundance of species tells us much about where the fish live and the health of the stocks.
Fish scales tell us about the life history of each individual fish and help develop the identification of the fish population structure of the Tweed. Scales are “read” in much the same way as growth rings on trees; the rings indicate how many times the fish has been to sea and returned to fresh water, and in this way the age of a fish can be measured.
Tweed has 20 species of fish of which only 10 are native. We know that some, such as Salmon and Trout, have a number of sub species and understanding these stocks is critical if the managers of the river are to make objective decisions.
The number of migrating fish returning to the river and how many of those are caught are of enduring interest to anglers as well as managers. It is impossible to measure this directly on a large river like the Tweed but we do have means to do it indirectly: tagging fish netted at the bottom of the river, and seeing how many are re-captured, enables estimates of both the numbers of fish and the proportion which are caught. Radio and acoustic tags have also been used to track fish to find out where they go, both up and downstream. Studies of Sea-trout are helping us understand the sex ratios of Sea-trout and Brown trout and the spatial distributions of their stocks.
We have fish counters on some tributaries of Tweed which count and video the migrating fish (although not always all of them). This allows us to identify the fish by species and also to monitor when the fish run.
Fish catches are the best historical information that we have and the analysis of historic and recent catch data allows us to find the natural, long term changes in populations. When appraising fish stocks it is always necessary to take the long view, and the historic catch data collected from the Tweed shows some very long-term trends for both Salmon and Sea-trout.
Biodiversity is a much used but often misunderstood term. The historical fashion for introducing new (sometimes called “alien”) species everywhere is now widely known to be potentially very damaging to the environment e.g. Giant Hogweed or American Signal Crayfish. We work with other agencies in the catchment to promote natural biodiversity of its native species and to protect Tweed’s special ecological status.
Predators of fish are always seen as damaging by anglers and may well be so. However to be sure of this we monitor predators in the catchment both through main stem counts and index monitoring at roosts, and at strategic points throughout the District which allow a measure of whole catchment distribution to be made. We also analyse the frequency of damage types on young fish in relation to run timing and sizes, using the existing fish traps.
Tweedability - Tweed Wheelyboats
We developed, and now operate, specialist boats for less-able anglers in concert with The Wheelyboat Trust and the River Tweed Commission. Tweedability boats are specifically designed for use on fast-flowing rivers such as Tweed. The user does not have to leave his or her wheelchair to access the boat or to fish. The boats, which are highly manoeuvrable and stable, can be rowed or powered by an outboard motor. Tweedability boats are extremely well-rated by both the Boatmen and anglers who use them.
We operate a number of fish traps seasonally that help us to understand the population dynamics and relationships of migratory fish and their connections with their environments. Cutting-edge chemical analysis can show the origins of trout fry as being from either Sea-trout or Brown trout.
Whether or not there is global warming, it is beyond dispute that we have significant changes in climate. This affects all kinds of species and so we monitor water temperatures and conductivity at key points within the catchment. With long enough data sets, analysis of their relationship with electro-fishing, or other data, may indicate long term trends.
We work with all relevant bodies and agencies impacting on fisheries management, both in the Borders and nationally. Starting from a position of fact is always more productive and we contribute to the better management on the Tweed catchment as a whole.