Most species have strong habitat preferences

David Thomas/BirdLife Birds are found in all major habitats, but forest is particularly important Zoom In

All major habitats have their characteristic bird species, though forests support particularly large numbers. Region by region, each of the world’s biomes supports a distinctive set of bird species found nowhere else. Threatened birds show similar patterns.

Most bird species show clear habitat preferences

Birds occur almost everywhere on Earth, in all the major habitat types, from polar ice caps to equatorial rainforest, from the open ocean to true desert. Their degree of specialisation varies greatly, but most species show a clear preference for one or more habitat. Some habitats support many more species than others. Forest, especially moist forest in tropical and subtropical regions, holds by far the greatest numbers, with 74% of all bird species. Shrublands follow, holding 26% of species, while grasslands, savanna and inland wetlands each support about 15% of species. The habitat preferences of Globally Threatened Birds show a broadly similar pattern (see box 1).

Many bird species are confined to a single biome

Many bird species have their entire world distributions limited to within one of the world’s major terrestrial biomes — distinctive regional ecological units, such as the Eurasian high montane biome. Their evolutionary histories, and often quite narrow ecological requirements, have confined them to suitable habitat within a particular region. Thus, in Africa and Madagascar, where 15 biomes are recognised, some 910 bird species, 42% of the regional total, are confined to single biomes. The Guinea-Congo forests hold the largest total for a single biome (278 species), while just nine species are confined to the Fynbos of South Africa (box 2). Conserving representative areas of these distinctive habitats is clearly a priority and key sites within biomes are therefore included in BirdLife’s Important Bird Area programme.

Boxes: case studies and scientific analyses

Download SOWB pp.20–21 (PDF, 352 KB) containing the following:

1. Birds are found in all major habitat types, but forest is particularly important
a) The importance of each major habitat type for all bird species and for GTBs
b) The relative importance of each major habitat type for GTBs
c) The importance of each major forest type for all bird species and GTBs
d) Tolerance of GTBs to forest degradation

2. Many bird species are confined to just one of the world's terrestrial biomes
The terrestrial biomes of western Eurasia, Middle East, Africa and Madagascar