Can massive Highland restoration save the salmon from regional extinction?
The fate of one of the world’s most iconic species hangs in the balance across the Highlands of Scotland, and in many other parts of Europe.
Due to climate change, water temperatures now frequently surpass the crucial 23 degree level above which survival of the Atlantic salmon is not sustainable.
Wild Europe is engaging through its associate The European Nature Trust (TENT) in initiation of a massive ecological restoration programme to save the salmon and its aquatic habitat. But can this be implemented in time?
Addressing the threats
This is the latest and most lethal threat in a saga of over-fishing, pollution, deforestation, wetland drainage and loss of spawning grounds in catchment ecosystems. Less than 5% of original native woodland remains and over three quarters of peatlands have been damaged. Population of salmon is estimated to have fallen by over 70% since the 1980s, with rod catches in 2023 at their lowest since records began in 1952.
The potential disappearance of salmon and the degradation of its ecosystem not only threatens a famous keystone species, but loss of a significant element in the Highland economy. Its worsening plight was discussed in London on 20th January at a conference called by the Atlantic Salmon Trust.
Central to the endeavour to save the salmon is a model project based in the North East of Scotland. This was recently launched by the Cromarty Firth Watershed Environment Trust (CFWET) with the District Salmon Fisheries Board, and support from The European Nature Trust (TENT) and The Fishmongers Trust.
An inaugural CFWET Steering Group meeting, in which Wild Europe participated, initiated the project in May 2025. It aims to promote restoration in the Cromarty Firth catchment of a mosaic of wetland, woodland and grassland ecosystems across an area of seven main rivers spanning over 250,000 hectares (Map 1).
A parallel project, also with support from TENT, is being developed in the adjacent Kyle catchment area to the North where seven main river systems cover 160,000 hectares (Map 2). Led by the Kyle of Sutherland Rivers Trust (KSRT) this initiative aims to restore 200 km of riverine habitat together with extensive wetland and woodland restoration.
The growing impact of climate change makes it difficult to predict how long a timescale is needed for restoration to take effect. Working within a rough initial ten year target frame, a range of parallel activities is involved:
Rewetting of a network of peatlands, to boost storage and steady release of cooler water, while mitigating climate change through reversal of current carbon emissions and stabilisation of storage, as well as alleviating flood risk from increasingly erratic precipitation. This is generally the fastest-acting element in the restoration jigsaw for lowering water temperatures, at an altitude and latitude where tree growth can be relatively slow.
Planting of native trees – riparian woodlands to provide cooling bankside shade and a source of invertebrate food, with larger montane woodlands further back from the watercourses to enable lower temperatures and higher humidity over extensive areas. This will strengthen climate mitigation through carbon sequestration, together with storage, supporting further alleviation of flood risk.
Linkage of wetland and woodland into a mosaic of varied habitat, overlapping to create ‘ecotones’, which can support a progressive enrichment of biodiversity
Potential further linkage to litoral (sea shore) restoration of seagrass together with tidal marshes – themselves sequestrating major volumes of carbon, and providing shelter for migrating salmon and many other aquatic species
Enhanced fishery support – providing riverine hatcheries, improved migration access, in-river habitat enhancement, reinstatement of natural meanders and spawning grounds
Ancillary management: control of deer and livestock impact, creation of tree nurseries, usage of baseline surveys and Key Performance Indicators (KPIs) for impact assessment
Awareness raising, engagement and education: a widening partnership directly involving local communities, landowners, NGOs, NatureScot, schools, corporates, tourism enterprise and a variety of other interests
Wider replication – the biggest inland catchment project in Europe?
CFWET in tandem with Fishmongers Trust is promoting linkage of a wider network of fishery and river catchment organisations across the whole Highland area, involving replication of these projects. Keen interest is being shown elsewhere in the UK and Europe.
Following initial restoration, management should mainly come from natural rather than human processes. This represents the most cost-effective approach for largescale re-emergence of enriched and resilient ecosystems, with non-intervention a key element in the long-term protection required for sustainable action.
The massive scale of the task ahead will need all available funding inputs – including government grants, corporate donations through PR and CSR agendas, together with significant inputs from landowners whose estate values could be significantly enhanced.
Ecosystem services can provide further funding from carbon and biodiversity credits, together with sponsorship for flood mitigation and clean water provision by utilities, manufacturers and local authorities. Peatlands alone in the Highlands hold an estimated 1.8 billion tonnes of carbon, with 80% requiring restoration, and advances in satellite based mapping of condition should further facilitate funding.
Urgent need for scale
A calculation is rapidly needed to establish the extent and mix of ecosystem restorations required to halt and reverse the impact of climate change before disappearance of the salmon and further degradation of its habitat becomes potentially irreversible.
The potential scale of restoration, if conducted swiftly, could also alter local microclimates, building further resilience to climate change with potential for significant mitigation.
Will actions be undertaken rapidly enough, at sufficient scale, for successful impact? How far can the momentum of climate change be halted and reversed?
The Glasgow COP promoted restoration to address climate change and biodiversity loss. This is an excellent opportunity for Scotland to lead the rest of Europe in a world class endeavour to address these twin crises.