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Is the Arctic vulnerable to IAS?

Climate change is having an observable influence on our oceans. In recent times, the Arctic has been significantly affected by increasing ocean temperatures, contributing to greater melting of sea ice and increased periods of open water.

The Svalbard archipelago is in a region that has seen significant ocean temperature increases in the last decade. It is predicted that the seawater temperature in the region is likely to increase by around 1°C within the next 20 years, caused by more frequent and prolonged marine heat waves.

Increasing loss of sea ice coverage and rising sea water temperatures are predicted to significantly increase the risk of successful introductions of marine IAS. Elevated levels of sunlight reaching the sea surface, caused by the reduction in sea ice cover are also predicted to result in enhanced primary production.

Consequently, climate change and the subsequent changes to the food web dynamics in the Arctic may also mean that some of these IAS will outcompete indigenous species for food.

Which IAS are already established in Svalbard?

Seven marine IAS have been reported in Svalbard, using eDNA samples collected from soft sediment in Kongsfjorden, northwest Svalbard. Several other IAS have been reported as biofouling on ship hulls, floating debris and in ship ballast water discharged near Svalbard ports, although their establishment in the area isn’t confirmed.

Twenty-four marine IAS have also been highlighted by the Norwegian Biodiversity Information Centre as potentially becoming established in Svalbard within the next 50 years based on their current distribution in the bordering sea areas.

For example, the red king crab has established populations in the southern Barents Sea. The Pacific pink salmon and a few individuals of the snow crab have been found in Svalbard waters since 1961 and 2017, respectively.

Populations of previously locally extinct species, for example mussels of Mytilus spp. complex have also been re-appearing in Svalbard after a thousand-year absence. Shipping and anthropogenic flotsam, including large plastic debris, have been identified as potential vectors.

How can the expected IAS affect Svalbard’s biodiversity?

From our horizon scanning work, seven species were selected from an initial list of 114 species, presenting a moderate to high risk of being introduced, establishing and having a negative impact on the biodiversity of the Svalbard archipelago. These species included the Red King Crab, the Snow Crab, the Orange Ripple Bryozoan, the Pink Salmon, a tunicate known as Sea Grapes, the Violet Tunicate and the Carpet Sea squirt.

Horizon scanning is a systematic process that can be used to predict potential high-risk IAS that are likely to occur in a particular area within a given timescale. It works as an “alert system” to identify a species of concern and then to undertake a rapid, expert-led risk assessment to determine the management response required to prevent introduction.

What about human health?

The horizon scanning did not report any foreseen impact on the health of the inhabitants on Svalbard. It is important to note, however, that microorganisms were not included due to the lack of information on these species. This remains a critical knowledge gap for predicting the impacts of marine IAS.

How do natural and human factors interact in introducing invasive species?

The remoteness of the Arctic and the harsh environmental conditions have made it more resistant to the arrival of new species. The likelihood of new IAS becoming established is accelerating due to the warming of the Arctic and increased human activity that is giving organisms new paths to travel.

Depending on how many IAS survive, some Arctic aquatic habitats will be more vulnerable than others. The strong, advective nature of the northwards flowing current from the Atlantic towards Svalbard both transports organisms and leads to increasing seawater temperatures and reduced ice cover. This current has already facilitated the northwards spread and establishment of species native to more southern Arctic waters, for example the blue mussel, the Atlantic mackerel and the Atlantic snake pipefish.

It is also likely to facilitate natural processes, such as rafting on driftwood or seaweed, or through the dispersal of pelagic life-stages. It is highly likely, therefore, that this current, in combination with the rising sea temperatures predicted for the Svalbard archipelago and the wider Arctic will facilitate the establishment of other IAS through this natural pathway.

One of the most important anthropogenic pathways at present is shipping, either via discharges of ballast water or hull fouling. While Norway has now ratified the Ballast Water Convention, logistical and technical challenges still exist, with many ships yet to fully comply with the regulations from 2017. There is still the risk, therefore, of marine IAS species being introduced into ports in the Arctic, including Svalbard, although it is likely that many of these species will be unable to survive.

The International Maritime Organization (IMO) has also introduced voluntary guidelines to minimise the transfer of IAS by biofouling, however, since these guidelines are not mandatory and there are currently no requirements to inspect the vessels entering ports, such as those in Svalbard, this pathway may present one of the key threats to marine biodiversity and the economy in the high Arctic.

What tools are there to monitor IAS in the Arctic?

Unfortunately, there is relatively little baseline data available on marine IAS and their impacts in the Arctic, since they have only been seen as an increasing threat over the last decade.

Additionally, the lack of effective and rapid monitoring techniques has contributed to the limited information on IAS in the Arctic. Recent advances in environmental DNA metabarcoding techniques, however, are now enabling the early detection of some marine IAS in the Arctic, although ground-truthing and repeated sampling is still required to determine whether these species will survive, become established and subsequently cause any impact.

Horizon scanning can also provide a first step in the management of IAS, in which species are both risk assessed and prioritized, so the limited resources can be more targeted. This tool could be used alongside early warning systems, such as AquaNIS, an information system dedicated to aquatic non-indigenous and cryptogenic species for a more balanced management strategy. This would strengthen surveillance and provide further opportunities to identify the high-risk species.

What is the Arctic Invasive Alien Species Strategy and Action plan?

The plans have been produced by the Arctic Council and clearly identify the threat from IAS and the need to protect the regions environment and human health. Three key priority areas are highlighted in this strategy, including the need to improve the knowledge base, prevent the introduction of IAS and rapidly detect and respond to introductions as they occur.

Is it possible to stop or slow down the spread of IAS in Svalbard?

“In my opinion, it is highly unlikely that we will ever be able to stop the introduction of IAS in Svalbard, but through the implementation of biosecurity measures ‘pre-invasion’ or in the early stages of invasion, the risk and associated costs can be significantly reduced compared with the substantial expense of eradicating or managing an outbreak once established.”

To its advantage, Svalbard, as in the case of many other areas in the Arctic, only has a few ports of entry and strict regulations are already in place on shore landings and no-go areas. These measures can help prevent and mitigate IAS arrival and establishment, particularly species transported in ballast tanks.

Biosecurity planning though can be further strengthened by horizon scanning, which can identify likely high-risk IAS, other pathways of introduction and the risk that certain species can pose to biodiversity, the economy and human health.

Last update: 31. January 2025