In a world of rapid anthropogenic land use changes and declining biodiversity, there is an urgent need for understanding the state of biodiversity to aid management and conservation. The knowledge about biodiversity in Iceland is limited, particularly in the light of accelerating land use changes, which rate among the most rapid in Europe. In this study, we assessed the importance of different habitats for avian biodiversity by surveying 200 random sites in the lowlands of South Iceland and linking these to land uses attained from the Icelandic Farmland Database. Birds were surveyed in the five most common vegetated habitat classes, other than agricultural land: wetland, semi-wetland, rich heathland, grassland and poor heathland.

 In total, 5128 individuals of 22 species were recorded and 95% of these belong to eight species, seven waders and the Meadow Pipit (Anthus pratensis). Of those eight species, five (Dunlin (Calidris alpina), Snipe (Gallinago gallinago), Whimbrel (Numenius phaeopus), Black-tailed Godwit (Limosa limosa) and Meadow Pipit) occurred in highest density in wetland but Oystercatcher (Haematopus ostralegus) and Redshank (Tringa totanus) occurred in highest densities in grassland and Golden Plover (Pluvialis apricaria) in poor heathland. Total density of the eight species in the five habitats ranged from 274 individuals per km² in poor heathland to 640 individuals per km² in wetland. Different measures of the avifauna in South Iceland suggest that wetter habitats are of greater importance for birds than the drier ones. Despite the importance of wetlands for avian and other species, human actions have extensively promoted the loss these habitats with inevitable negative consequences to biodiversity.