Pink salmon
Pink salmon (Oncorhynchus gorbuscha)
The pink salmon (Oncorhynchus gorbuscha) is an anadromous fish native to the Pacific Ocean. Pink salmon was stocked in the Kola Peninsula in Russia, from 1956-1979 and again from 1985-1999, to serve as a fisheries resource. It has recently spread throughout the North Atlantic Ocean in unprecedented numbers and has now been reported in most countries within the NASCO Convention Area. Most pink salmon occurring in the North Atlantic has an odd-year spawning cycle. In some areas of Northern Norway and Finland, there are now more pink salmon than Atlantic salmon entering the rivers in odd years.
Although pink salmon has been reported for many years in Northern Norway and its abundance has increased tremendously in recent years in Norway and across the North Atlantic, relatively little research has been conducted regarding the impacts and interactions of pink salmon with native fish species, notably other salmonids. Being anadromous and sharing similar life history traits with the Atlantic salmon, pink salmon inhabits marine environments to grow and mature before returning to fresh water to spawn, and subsequently dies. Therefore, determining potential impacts and ecological consequences at both local and international scales throughout these environments can be challenging. The utilisation of environmental DNA (eDNA) has become an important tool, especially in areas where pink salmon abundances are not so dominant, for monitoring and understanding the presence, distribution, abundance and recruitment potential of the species.
It is important to note that in Russia, pink salmon is deemed a resource, but in most other NASCO Parties, it is classed as an invasive or alien species. To mitigate against increasing numbers of pink salmon, several countries have adopted special fishing licences, created new regulations regarding catching pink salmon and produced risk assessment documents. In 2023, Norway enacted ambitious local and national management efforts to construct traps in the lower part of over 50 rivers to remove and kill as many pink salmon as possible before they spawn. This effort was estimated to have successfully removed 250,000 adult pre-spawned pink salmon in total. Mitigation measures in Norway aiming to reduce and control the abundance of pink salmon can reduce the risk that pink salmon will establish in high numbers in other parts of Europe.
Concerns related to the presence of pink salmon within the NASCO Convention Area and the potential for negative impacts to wild Atlantic salmon productivity have been voiced since as early as 2011. Given the unprecedented increase in abundance and expansion of their distribution circa 2017, these conversations have become more focused and targeted. During the NASCO Annual Meetings in 2022 and 2023, significant concerns were raised about the ongoing and future threat of non-native pink salmon to native wild Atlantic salmon stocks in the Convention Area. To date, very little research has been carried out on the impacts of pink salmon across the North Atlantic region, which means more information on distribution, and hypothesised potential impacts, needs to be discussed and taken into consideration to enable the informed management of aquatic ecosystems.
In 2023, the Council of NASCO agreed that a half day Theme-based Special Session on pink salmon would be held at its Annual Meeting in 2024, the report of which is available below:
The Working Group on Pink Salmon
In response to the concern raised by NASCO Parties / jurisdictions, NASCO established a new Working Group on Pink Salmon in 2024 to facilitate the exchange of information on the status of pink salmon across the Convention area. The Group is also tasked with identifying best practices for monitoring, knowledge gaps and corrective measures as related preventing adverse effects from pink salmon on wild Atlantic salmon stocks. The Group will also facilitate the sharing of information and the status of pink salmon within each Party / jurisdiction.
The most recent meeting of the Working Group was held in 2026. The reports of this and previous meetings are available below:
Publicity and Educational Materials
Publicity and educational materials have been developed by several of the jurisdictions who are members of the Working Group. These materials include information on how to identify pink salmon and report its presence, for example when caught by anglers. Such material has been provided to the NASCO Secretariat by:
Relevant Publications
- Nielsen, J., Rosing‐Asvid A., Meire, L. and Nygaard, R. 2020. Widespread occurrence of pink salmon (Oncorhynchus gorbuscha) throughout Greenland coastal waters. Journal of Fish Biology, 96, 1505–1507. https://doi.org/10.1111/jfb.14318
- Millane, M., Walsh, L., Roche, W.K. and Gargan, P.G. 2019. Unprecedented widespread occurrence of Pink Salmon Oncorhynchus gorbuscha in Ireland in 2017. Journal of Fish Biology, 95, 651– 654. https://doi.org/10.1111/jfb.13994