How Scotland’s wild Atlantic salmon are faring

A leaping salmon, achieving the seemingly impossible to return to the upper parts of the very river in which it hatched after a year or more in the ocean, remains one of the most iconic images of Scotland’s wildlife. But how are Scotland’s wild Atlantic salmon faring? As our consultation on proposals for the conservation of Atlantic salmon during the 2024 fishing season launches, we look at some of the scientific data that underpins the management of this remarkable fish.

Every year scientists from the Marine Directorate of the Scottish Government assess the status of 173 Scottish salmon stocks using information collected from river fisheries and automatic fish counters combined with environmental information, such as water flow. The stock levels over the past five years are compared to an internationally agreed benchmark which aims to maintain stocks at sustainable levels. This allows the stocks to be categorized as in good, moderate or poor status with the reduction in salmon numbers driving an increase in the number of stocks in poor status (Figure 1).

Figure 1: The number of stocks assessed as being in good, moderate or poor conservation status (out of 173 stocks) for the 2016-2024 angling seasons.

The larger rivers, which contain most of Scotland’s wild salmon, tend to be in good conservation status. This means that approximately 80% of the total number of fish estimated to be in Scottish rivers are from areas in good conservation status.  However, declines in the number of salmon in areas in good conservation status highlights the need for action to safeguard this iconic species.

The proposed grades for the 2024 angling season highlight that the majority of stocks (112 out of 173) are thought to be in poor conservation status and these are spread throughout the country (Figure 2).

Figure 2: Proposed conservation status of the 173 assessed stocks for the 2024 angling season.

The number of wild Atlantic salmon returning to Scottish coastal waters has declined since estimates began in the 1970s (Figure 3).

Figure 3: Estimated number of wild Atlantic salmon returning to the Scottish coast together with estimates of the number surviving to spawn in Scottish rivers (source: returns to coast ICES WGNAS/MSS; spawner numbers MSS).

Fisheries managers have been able to offset these declines by greatly restricting the killing of wild salmon in fisheries, but since around 2010 there has also been a decline in the spawning stock.

The reasons behind the widespread fall in wild salmon numbers in Scotland and across the North Atlantic ocean are highly complex. The evidence suggests that changes in oceanic conditions driven by climate change are at least partly to blame, but it is likely that many different factors in rivers and at sea play a role.

To address the declines and build resilience in salmon populations to the effects of climate change we worked together with multiple partner organisations to develop the Scottish Wild Salmon Strategy and accompanying Implementation Plan.

Alongside reducing pressure from fisheries, actions under the plans include supporting planting riverside trees to shade rivers from rising temperatures and restoring natural river flows by removing obsolete weirs and dams. Steps are also proposed to minimise the impacts of salmon farming on wild populations as well as continuing to co-operate internationally to improve the survival of salmon at sea.

Have your say on proposals for the conservation of Atlantic salmon during the 2024 fishing season by taking part in our consultation which runs until 8 September 2023.

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