Birds tell us about the world's biodiversity

BCST Birds have huge popular appeal – and the amount of information about them is impressive Zoom In

Birds are useful environmental indicators, helping us to locate important places and alerting us to environmental change. While biodiversity as a whole is expensive to monitor, it is easy to count birds. And because birds are so popular, we already know a lot about them.

We know a lot about birds

We have better information on birds than on any other comparable group of organisms. Although many gaps remain, we know a great deal about their taxonomy, distribution, habitat preferences, movements, numbers, population trends, ecology and behaviour. Compared to other groups, birds are easy to observe. They are relatively big, attractive and conspicuous; most are active by day; they can be identified in the field, from a distance; and although they are diverse, the number of species (c.10,000) is manageable. For all these reasons, people enjoy watching birds and are able to provide useful data (see box 1).

Birds are useful indicators

Biodiversity as a whole is very expensive to measure and monitor. Although birds cannot be full representatives of all biodiversity, the evidence shows that they are an excellent starting point (box 2). Most importantly, the amount of information that we already have on them makes them uniquely useful. Birds are barometers for change in the wider environment. Our knowledge of birds’ ecology allows us to interpret changes in their populations and distributions. Changes in the overall threat status of the world’s bird species reflect changes in the underlying threats to biodiversity. Birds are found all over the world (box 3); on a broad scale, their distribution patterns highlight parts of the globe that are especially important for biodiversity conservation. Endemic Bird Areas coincide with the great majority of regions particularly significant for mammal, snake, amphibian and plant species in mainland sub-Saharan Africa. Birds are also beacons for sites. Important Bird Areas (IBAs) form a global network of sites that effectively pinpoints much other terrestrial biodiversity. IBAs are an excellent starting point for identifying a full set of key biodiversity areas, especially where information for other taxa is scarce or patchy.

Boxes: case studies and scientific analyses

Download SOWB pp.6–7 (PDF, 327 KB) containing the following:

1. Birds have huge popular appeal, and the amount of information about them is impressive

2. Birds are good (though not perfect) indicators

3. Birds are found almost everywhere in the world, from the Poles to the Equator
The distribution of the world's bird species by biogeographic realm and country