Iceland is a young landmass formed by volcanic activity on the Mid-Atlantic Ridge. Its geographic isolation, far from continental shelves, has profoundly shaped its animal life. This distance means Iceland’s biological diversity is naturally lower compared to continental regions. However, the life forms that have colonized this subarctic environment are highly specialized and resilient, resulting in a unique array of species adapted to the harsh climate and limited resources.
Terrestrial Mammals
The terrestrial fauna of Iceland is notably sparse, with only one species of land mammal considered truly native: the Arctic Fox (Vulpes lagopus). This resilient canid arrived during the last Ice Age, likely crossing on sea ice. Its survival is aided by a coat that changes from white or blue-gray in winter to brown or gray in summer, offering year-round camouflage.
Other wild land mammals were introduced by humans, either intentionally or accidentally. The American Mink (Neovison vison) escaped from fur farms in the 1930s and established a widespread population. This invasive species impacts native bird populations due to its predation on eggs and chicks. Reindeer (Rangifer tarandus) were introduced in the 18th century and now roam freely, primarily concentrated in the eastern parts of the country.
Rodent species, such as the wood mouse, house mouse, and brown rat, arrived inadvertently with human settlers and ships. While iconic domestic animals like the Icelandic horse and sheep are an integral part of the landscape, they are managed livestock and not wild fauna. The scarcity of native land mammals remains a defining characteristic of Iceland’s ecosystem.
Avian Diversity
While land mammals are few, avian diversity is extensive, especially along the rugged coastline and in wetlands. Iceland serves as an important breeding ground and migratory stopover point for numerous bird species. The most famous is the Atlantic Puffin (Fratercula arctica), with an estimated seven million individuals breeding here during the summer months. This population represents a significant portion of the world’s total puffin population, nesting in vast colonies on cliffs like those at Látrabjarg and the Westman Islands.
Other abundant seabirds include the Northern Gannet, known for its spectacular diving technique, and various auks like the Common Guillemot and Razorbill, which nest on sheer cliff faces. The Arctic Tern (Sterna paradisaea) utilizes Iceland as a key breeding location, completing the longest migration of any animal on Earth as it travels between the Arctic and Antarctic. The Gyrfalcon, Iceland’s national bird, and the White-tailed Eagle are the largest birds of prey. This concentration of birdlife makes coastal areas a dynamic spectacle, particularly during the nesting season from May to September.
Marine Ecosystems
The cold, nutrient-rich waters of the North Atlantic host Iceland’s largest and most varied animal community. At least 23 species of cetaceans, including whales, dolphins, and porpoises, inhabit the exclusive economic zone. Humpback Whales and Minke Whales are commonly sighted in coastal feeding grounds, often alongside pods of White-beaked Dolphins and Harbour Porpoises.
The immense Blue Whale, the largest animal ever to have lived, also frequents these waters to feed on abundant plankton. Orcas, or Killer Whales, are regular visitors, often following shoals of fish close to the shore. Two species of seals regularly breed and pup along the coast: the Harbour Seal and the larger Grey Seal.
The highly fertile fishing grounds are sustained by strong ocean currents, supporting a massive biomass of commercially important fish species like Cod and Haddock. These foundational fish stocks form the backbone of the entire marine ecosystem, providing the necessary food source for the large migratory whales, seabirds, and seals that congregate around the island. This marine wealth is the primary driver of the country’s biodiversity, far exceeding the life found on the land itself.