Wet Grasslands as a Green Infrastructure for Ecological Sustainability: Wader Conservationin Southern Sweden as a Case Study

Biosphere Reserves aim at being role models for biodiversity conservation. This study focuses on the unsuccessful conservation of waders (Charadrii) on wet grasslands in the Kristianstad Vattenrike Biosphere Reserve (KVBR) in southern Sweden. Predation on nests and young has been proposed as one reason contributing to the decline of waders. We explored this hypothesis by comparing two landscapes, one with declining (KVBR) and one with stable (Östergötland) wader populations on managed wet grasslands in southern Sweden. Specifically, we tested three predictions linked to predation on wader nests and young, namely that (1) the relative abundance of avian predators and waders; (2) the avian predator abundance; and (3) the predation rate on artificial wader nests, should all be higher in declining versus stable populations. All predictions were clearly supported. Nevertheless, predation may not be the ultimate factor causing wader population declines. We discuss the cumulative effects of landscape change linked to increased food resources for predators, reduced wet grassland patch size and quality. Holistic analyses of multiple wet grassland landscapes as social-ecological systems as case studies, including processes such as predation and other factors affecting waders, is a promising avenue towards collaborative learning for wet grasslands as a functional green infrastructure. However, if governance and management approaches can be improved is questionable without considerable investment in both ecological and social systems.