Impacts of grassland management on wader nest predation rates in adjacent nature reserves

Abstract

Wetlands have undergone significant loss and degradation over the past century, primarily through agricultural development. In the UK, wet grassland habitats support important breeding wader populations, but agricultural intensification has led to severe population declines. Management on nature reserves can be successful at attracting breeding waders, but productivity has been limited by the impacts of generalist predators of nests and chicks in these relatively small areas. Targeting agri-environment management to form buffer zones around reserves has been proposed as a potential strategy to improve landscape connectivity. However, the implications of such strategies for predator movement and activity are unknown. Here we assess whether predation rates of wader nests and predator activity within and across a wet grassland reserve are influenced by whether adjacent farmland is under agri-environment scheme (AES) management for breeding waders. In fields adjacent to AES-managed land, fox activity was higher and nest predation rates remained constant with increasing distance from the reserve edge into the reserve. Conversely, fox activity and wader nest predation rates were lower in fields close to the reserve edge and adjacent to commercial land, and increased with distance from the reserve edge although only to levels seen elsewhere on the reserve. This suggests that predators concentrate activity away from commercial farmland, and that the consequences for nest predation of deploying AES around nature reserves will likely depend on the extent to which they attract breeding waders and the strength of any consequent density-dependent effects on predation rates.