Developing effective agricultural wetland management to reduce predation and improve wader breeding outcomes

Anthropogenic changes are driving biodiversity losses worldwide. Habitat loss/degradation causes many of these declines, but the extent to which impacts are direct - loss of foraging or breeding locations - or indirect - altering predation via habitat simplification or fragmentation - often remains unclear. Disentangling the impacts of, and interactions between, the fundamental processes of habitat change and predation pressure on declining populations remains a key issue within wildlife management worldwide.

Agriculture exerts a massive global footprint on biodiversity. However, crucial questions remain over how land should be apportioned within farmed landscapes to maintain biodiversity while meeting increasing food demands. This land sparing-sharing debate is increasingly being applied to temperate regions, but remains unstudied in many nature-rich northern farming systems. Yet this knowledge is essential given the large amounts of money distributed via agri-environment schemes (AES) and concerns surrounding their effectiveness for biodiversity preservation. In addition, considering an entire mixed farming system as 'nature-rich' can mask important variation in the contribution of habitat type and the habitat matrix to the maintenance of biodiversity.

UK farmed landscapes exemplify these processes and conflicts; farmland birds are declining widely, but for many taxa there remains uncertainty over whether the direct impacts of habitat change, or indirect impacts from predation pressure, or the interaction between these, are the key mechanisms driving declines. Understanding this is central to designing farmed landscapes that effectively maintain biodiversity alongside food production.
We will utilise the unique opportunity provided by a natural experiment following the introduction of a non-native predator and ongoing attempts to remove it, combined with a diverse farmland habitat matrix, and the presence of nationally important populations of waders, within the Orkney Islands. This has resulted in intersecting gradients of predation pressure and habitat type with exceptional large-scale existing data on predator and prey distributions and abundance, making it an ideal system to investigate the extent and importance of these twin drivers in contributing to species' declines.