Adaptive management and targeting of agri-environment schemes does benefit biodiversity: a case study of the corn bunting Emberiza calandra

摘要: Summary 1. Agri-environment schemes (AES) are the main European policy response to biodiversity loss caused by agricultural intensification. Maximizing their effectiveness is a key challenge. Monitoring essential inform adaptation and improvement of over time, understand how measures may need vary across species’ range. 2. We measured changes in breeding abundance severely declining bird, corn bunting Emberiza calandra, AES Scotland 7 years 71 farms. Two were monitored, one with general management for farmland birds, targeted, adaptive buntings. We use these data estimate proportion population that must influence halt overall decline. 3. Corn buntings increased 5·6% per annum on farms targeted AES, showed no significant change declined 14·5% outside AES. 4. In arable-dominated areas, food availability reversed declines. However, where high nested grasslands, an additional option delayed mowing was achieving increase. 5. Results suggest approximately 72% mainland receive current decline. In 2009, only 24% this way. 6. Synthesis applications. capable reversing declines Scotland, same likely benefit wide range other taxa too, but require geographical targeting flexibility adapt improve options, backed expert advice. Targeted provision required level will cost £120 000 annum, 500–600 ha under appropriate management. This 0·02% annual subsidies paid Scottish farmers, 0·5% land remaining bunting. These outcomes illustrate value monitoring studies assess scheme effectiveness, identify improvements, determine scale implementation species