Landscape context influences efficacy of protected areas and agri-environment scheme delivery for breeding waders.
Abstract
Protected areas (PAs) and agri-environment schemes (AESs) are the main policy mechanisms for addressing terrestrial biodiversity loss in Europe. Landscape context can moderate their efficacy but has not been studied for both mechanisms concurrently. Both mechanisms are widely used to address ongoing declines of waders breeding on lowland wet grassland. Using a repeat, nationwide (England) survey, we investigate the role of PA status (nature reserves and a statutory designation), AES (bespoke and general options), surrounding landcover (up to 1500 m), soil properties and range position (core vs. periphery) on field-level breeding occupancy and abundance change of four declining waders between 2009/2010 and 2020/2021. Field occupancy of Northern Lapwing Vanellus vanellus, Common Redshank Tringa totanus and Common Snipe Gallingo gallinago was associated with PA status, being highest in reserves. Abundance change was more positive on fields in reserves than in unprotected or designated non-reserve sites for Lapwing, Redshank and Eurasian Curlew Numenius arquata. Fields under bespoke wader AES management were more likely to hold Lapwing and Redshank, which could reflect local redistribution or effective option targeting. Although there was limited evidence that AES increased wader abundance, habitat maintenance options within and outside PAs maintained, and habitat creation/restoration options within reserves increased, Lapwing and Redshank abundance. Fields surrounded by more wet grassland were more likely to be occupied by Lapwing and Curlew, particularly in designated non-reserve sites (Curlew only) and reserves. The same was true for Redshank and Snipe, but only in designated non-reserve sites (Snipe only) and reserves. For Lapwing and Redshank, abundance change was more positive where surrounding wet grassland cover was greater. Synthesis and applications. Landscape context strongly moderates PA efficacy for breeding waders, with reserve fields performing particularly well when surrounded by favourable habitat. Further work is needed to establish the mechanism(s) behind these findings, but future conservation investment might prioritise expanding existing reserves, or the creation of large, new blocks with reserve-level management. Future deployment of wader AES outside of reserves could focus on population maintenance, but to increase abundance schemes need to deliver higher habitat quality at sufficient scale.