Arctic under pressure: invasive species as a new threat to the region

Arctic ecosystems have so far remained isolated and relatively safe. However, a steadily warming climate and a growing number of tourists pose a serious threat to their future, opening the door to invasive species. The latest study shows that thousands of plants from around the world may find optimal conditions for development in the Far North. And change it irreversibly.

Climatic niche for 2.5 thousand species

The study conducted by scientists from the Norwegian University of Science and Technology (NTNU) covered 14 thousand representatives of the plant kingdom and as many as 51 million known occurrence records. The researchers used the extensive GBIF database (Global Biodiversity Information Facility), which collects data on the distribution of plants, fungi, animals, and microorganisms worldwide.

It turned out that in the face of increasingly higher temperatures, favorable conditions for development in the Arctic could be found by 2,554 invasive species from around the world, not only from cold climate zones but also from the temperate zones of Europe and North America. If seeds manage to reach new areas, they may begin to spread intensively. Today this is much easier than in the past. Humans also indirectly participate in seed dispersal, as increasing numbers of people visit the Arctic, for example for scientific or tourist purposes.

Which invasive species are particularly dangerous for the Arctic?

The authors thoroughly examined the occurrence of alien species in the Arctic region to identify so-called hotspots, locations most threatened by invasions from warmer areas. Exceptionally favorable conditions for plant intruders were identified in Western Alaska, where more than 1.2 thousand invasive species could become established. Other highly threatened areas include southern Greenland, northern Iceland, and Norway.

The scientists selected alien species with the largest projected ranges, for which changing climatic conditions in the Arctic will be particularly favorable. These include, among others, Arnica angustifolia, Koeleria spicata, and Micranthes nelsoniana, all three could appear across more than 90 percent of the Arctic area. A significant threat to subpolar ecosystems is also posed by Alnus alnobetula and Senecio nemorensis.

A race against time

Identifying potential threats alone is not enough to prevent the negative effects of the spread of invasive species in the Arctic region. It is important to act quickly and to implement preventive measures early wherever they are needed.

Our long-term goal is to help identify alien species before they become invasive and problematic, says Tor Henrik Ulsted, one of the study’s authors. The new methodology developed by Norwegian scientists may improve this process.

In a rapidly warming Arctic, some invasive species may play a positive role by supporting ecosystem resilience. Others, however, will significantly disrupt existing ecological relationships. Planned actions must balance the monitoring of potentially harmful invasions with recognition of the inevitability of ecological changes occurring in this region.

The authors remind that limiting the impact of invasive species on ecosystems is one of the goals of the Kunming-Montreal Global Biodiversity Framework. According to this plan, implementation of its provisions should reduce the spread of invasive alien species by half by 2030.

---

Bibliography:

Ulsted TH, Westergaard KB, Dawson W, Speed JDM (2025) Horizon scanning of potential new alien vascular plant species and their climatic niche space across the Arctic. NeoBiota 104: 1-26. https://doi.org/10.3897/neobiota.104.165054