A total of 110 bird species are known to have nested in Iceland. Of these, 75 species breed in Iceland on a regular, ongoing basis, i.e., they have nested here every year for a 10-year period (2008–2018). An additional seven species occasionally breed in Iceland and are on the verge of establishing a permanent breeding population. Some of these birds may soon colonise Iceland.
Virtually all breeding birds in Iceland are believed to have arrived here from Europe. They breed either all around the northern hemisphere or exclusively in the Northeast Atlantic. Only three species are North American in origin: the common loon (Gavia immer), Barrow’s goldeneye (Bucephala islandica) and harlequin duck (Histrionicus histrionicus). The rock ptarmigan (Lagopus muta) also probably colonised Iceland from the west, given that the Icelandic rock ptarmigan is most closely related to the Greenlandic population.
Iceland’s avifauna has a markedly different composition from that in more southerly countries. Seabirds, ducks, and waders are dominant, while there are comparatively few passerines, even though passerines account for around 60% of all bird species worldwide. The composition of Icelandic birdlife is shaped by Iceland’s relatively unvarying but frequently rich natural habitats. Iceland’s remoteness has also prevented its colonisation by several species.
The most common species groups of Icelandic breeding birds are ducks and other waterbirds (24 species – 32%) and seabirds (24 species – 31%). There are also 12 passerine species (16%), 11 wader species (15%), four species of predatory birds and owls, and finally the rock ptarmigan.
No bird species are endemic to Iceland. However, several sub-species live only in Iceland or breed here for the most part.