The River Ness Habitat Restoration Feasibility Study

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We are pleased to announce commencement of an exciting project focusing on the River Ness mainstem. The River Ness Habitat Restoration Feasibility Study aims to pinpoint threats to the habitat of wild Atlantic salmon in the River Ness and devise actions to increase natural production.

Like many other river systems across Scotland and the North Atlantic, the Ness has seen a significant decline in the numbers of returning adult salmon. The key drivers for this are thought to relate to climate change and survival at sea, where management options are limited, so we instead need to do all we can to maximise the numbers of healthy wild salmon smolts leaving our rivers.

Many of the key fisheries management projects being delivered by the Ness DSFB and its partners focus on the upper system, where there is evidence of significant local issues. The success of these projects will benefit entire system, particularly given that adult salmon have to swim through the lower system to reach the upper system. There have, however, been growing calls for specific action on the River Ness where catches have fallen considerably.

The mainstem River Ness at Laggan

The results of our spawning and juvenile surveys (aerial redd counts and electrofishing surveys) suggest that, in contrast to parts of the upper system, the ‘available’ spawning and nursery habitat in the River Ness is relatively well utilised. Therefore, if we are to increase natural wild salmon production in the River Ness, we need to consider the quality and quantity of the available habitat and whether there might be any opportunities to improve it.

A cluster of salmon redds in an area of spawning habitat in the River Ness

Sediment is constantly washed downstream through a river system, being replenished from above. It is this sediment that provides the spawning and nursery areas for fish. In the case of the River Ness, the downstream movement of sediment was effectively cut off by the construction of Ness Weir at Dochfour in the 1830’s. Gravel has also been actively removed from a number of areas of both the main river, its tributaries and a number of historical mill lades have been effectively cut off from the main river. This means that the river may have been slowly starved of spawning and nursery substrate over time, leading to suboptimal salmon recruitment.

Healthy looking juvenile salmon fry and parr captured during the survey at Dochfour on the River Ness in July 2020

Given the points above, the Ness DSFB has commissioned local experts cbec Ecoengineering to deliver the ‘River Ness Habitat Improvement Feasibility Study’. Funded by the Ness & Beauly Fisheries Trust, this study aims to provide a rigorous and comprehensive understanding of the current condition of the River Ness and specifically includes the following:

  • An initial desk-based assessment of the physical and ecological condition of the river to provide an understanding of how the river currently operates. This will be important to understand the system ‘reference state’ and how historic modifications may have resulted in the river deviating from this condition.
  • A field-based survey of the physical condition of the river (‘fluvial audit’) that assesses the distribution of morphological, sedimentary and ecological factors in combination with human impacts along the length of the study section of the river.
  • A series of maps detailing the present-day physical character of the River Ness to support the implementation of sustainable measures and to enhance habitat improving the natural conditions required for fish rearing and production.
  • A final feasibility report detailing the influence of historical human pressures on the current physical character of the River Ness and impacts on ecological condition and salmonid habitat. This will detail a number of potential habitat restoration or enhancement measures.

It is important to note that this initial feasibility study will not involve any actually on the ground habitat improvement works, rather it will identify whether such measures might be required. Any proposals for future works resulting from the study would be subject to landowner permissions, detailed designs, funding and the successful navigation of a complex consent process.

The field-based survey will be completed in July, with the final report completed by the end of 2021.

Full news release can be viewed here.

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