摘要：Rivers are affected by changes in catchment land-use and other modifications to theirchannel, floodplains and riparian zones. Such changes can affect biodiversity downstream,and specialist river birds might indicate the effects across multiple scales and throughdifferent ecological pathways. The risks of catchment-scale effects on rivers are especiallyacute in the Himalayan mountains, where the world’s greatest diversity of river birds occupiesone of the most rapidly changing riverine environments on Earth. Here, we use multivariateanalysis on data collected over two years to investigate the distribution of this group of birdsin relation to natural and anthropogenic variations in riverine habitats along one of the majorheadwaters of the Ganges. River bird distribution was linked to channel character, bankmorphology, aspects of river flow and land use. Riverine specialists were associated significantly with the least modified reaches characterised by faster flows, exposed bedrocks, bankswith pebbles, boulders with more intact riverine forests. Our data provide evidence fromwhich to develop specialist river birds as cost-effective indicators of human impacts on riverecosystems, but further work is needed to separate the effects of natural and anthropogenicinfluences. Such work could also guide conservation action to help balance the exploitationof catchment ecosystem services with the protection of river biodiversity.
