Bird populations have long been considered to provide a good indication of the broad state of wildlife in the UK. This is because they occupy a wide range of habitats and respond to environmental pressures that also operate on other groups of wildlife. In addition, there are considerable long-term data on trends in bird populations, allowing for comparisons between the short term and long term. Because they are a well-studied taxonomic group, drivers of change for birds are better understood than for other species groups, which enables better interpretation of any observed changes.
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