Iceland, a land shaped by volcanic activity and glaciers, possesses a unique ecological landscape. While many perceive Iceland as largely devoid of large, dangerous predators, its diverse terrestrial and marine ecosystems host various predatory species, including its sole native land predator, marine hunters, and occasional visitors.
Iceland’s Only Native Land Predator
The Arctic fox (Vulpes lagopus) is Iceland’s only native land mammal predator. It arrived on the island during the last ice age, traversing frozen sea ice from mainland Scandinavia and Greenland. These animals have adapted to Iceland’s harsh conditions, with a thick double-layered coat providing excellent insulation against temperatures as low as -50 degrees Celsius.
The diet of Icelandic Arctic foxes is varied and opportunistic. Unlike other regions where they feed on small mammals like lemmings, the Icelandic population largely preys on birds, their eggs, and carrion, especially along the coast. They also scavenge on marine mammals and fish, and in times of scarcity, may consume berries or even feces. Despite their predatory nature, Arctic foxes in Iceland pose no threat to humans.
Marine Predators and Rare Land Visitors
Icelandic waters are home to Orcas (Orcinus orca), also known as killer whales, which are prominent apex predators. Orcas in Iceland primarily feed on herring, often using coordinated hunting strategies like “carousel feeding” to herd fish. Their diet can also include other fish species, cephalopods, and marine mammals like seals.
Various seal species inhabit Iceland’s coastal waters, acting as significant marine predators. The harbor seal (Phoca vitulina) and grey seal (Halichoerus grypus) are the most common resident species that breed on Iceland’s shores. These seals are skilled hunters, primarily feeding on fish such as cod, herring, capelin, and flatfish, utilizing their sensitive whiskers to detect prey. Predatory seabirds, such as the Great Skua, also contribute to the marine food web by preying on other birds and fish.
Polar bears (Ursus maritimus) are rare, non-native visitors to Iceland, typically arriving on ice floes from Greenland. These occurrences are infrequent, with an average of one sighting every other year since 1951. Polar bears arriving in Iceland are often disoriented and hungry, posing a potential danger to humans and livestock, which usually leads to their removal by authorities.
The American mink (Neovison vison) is another introduced land predator, having escaped from fur farms in 1931 to establish wild populations across much of Iceland’s lowlands. While not a threat to humans, mink have negatively impacted bird populations, particularly ground-nesting seabirds, and freshwater fish like arctic char.
Factors Limiting Large Predator Populations
Iceland’s geographical isolation is a primary factor limiting its land predator populations. As an island, it has been historically difficult for large land mammals to naturally colonize. The Icelandic landscape also contributes to the limited diversity of large predators, lacking extensive forest cover and a variety of large prey animals. Human settlement, beginning in the 9th century, further influenced the predator landscape. Early settlers introduced domestic animals and hunted species like the Arctic fox for fur and to protect livestock, impacting their populations.