- Arctic fox: The Arctic fox (Vulpes lagopus) is native to the Arctic region, but has been introduced to some Arctic islands, where it preys on native bird species, including ptarmigans and long-tailed ducks.
- Norway rat: The Norway rat (Rattus norvegicus) has been introduced to the Arctic via human activities, such as shipping and whaling. These rats can compete with native species for food and habitat, and spread diseases.
- Snow crab: The snow crab (Chionoecetes opilio) is a marine invertebrate that has been introduced to the Barents Sea and other Arctic waters. Snow crabs can overgraze on benthic communities and compete with native species for food, disrupting the marine ecosystem.
- Purple loosestrife: Purple loosestrife (Lythrum salicaria) is a flowering plant native to Europe and Asia that has become invasive in some parts of the Arctic tundra. It spreads rapidly and forms dense stands that can outcompete native plants and reduce biodiversity.
- Quagga and zebra mussels: Quagga (Dreissena bugensis) and zebra mussels (Dreissena polymorpha) are freshwater bivalves that have been introduced to the Arctic via ballast water from ships. These mussels can rapidly colonize and alter aquatic habitats, affecting native species and potentially disrupting the food chain.
Efforts are being made to control the spread of invasive species in the Arctic tundra, including monitoring, habitat management, and public education. However, the introduction and establishment of invasive species remains a significant challenge, and their potential long-term impacts on the vulnerable Arctic ecosystem are still being studied.