Argyll Fisheries Trust: River Ruel and Eachaig Habitat Improvements

Purpose of Grant

To fund improvement works on the River Ruel and River Eachaig on the Cowal Peninsular in South Argyll, to reduce rates of riverbank erosion and fine sediment entering these rivers.

Project Description

The Cowal Peninsular has several rivers flowing into Loch Long and Kyles of Bute. The Trust had previously collected habitat and fish data on Atlantic salmon and sea trout in three of the major rivers in the region: River Ruel, River Eachaig, and the River Goil, over a period of 20 years. These studies have shown the habitat for fish in these rivers is sub-optimal due to influences of land use, water abstraction and climate change which have caused high rates of bank erosion and collapse.

The deposition of large volumes of fine sediment into the river had caused the coarse substrates in the riverbed to become clogged with silt and sand, much reducing the cover for young salmonid fish, spawning success and invertebrate abundance which are an important source of food for fish. In addition, the bank erosion had reduced the number of mature trees on riverbanks (and shading of the river channel) which are needed to manage water temperature in the warming climate.

Argyll Fisheries Trust sought funds to improve the survival and growth of young salmon and trout by reducing rates of riverbank erosion and fine sediment entering River Ruel and Eachaig using well-established green revetment techniques. The technique allowed the bankside vegetation and riverine habitat to recover. Management of existing trees (pollarding) and retaining large woody debris in the river was also undertaken.

The Fishery Trust undertook improvement works on over 400 meters of severely affected riverbanks at three locations which had a direct positive impact on 0.4 hectares of riverbed habitat and they also removed sources of silt affecting considerably more habitat downstream of the work sites.

Budget

A grant of £34,483 was given and this represented 73% of an overall project budget of £46,983.