Living in the Hedge: Farmland Reptile Diversity Is Driven by Hedgerow Structural Complexity and Landscape Connectivity

ABSTRACT The transition to agroecosystems promoting biodiversity is currently a major challenge. Agricultural hedgerows are structurally complex field margins with multiple vegetation layers. These semi‐natural linear habitats have significant potential for farmland biodiversity conservation by mitigating the negative impacts of natural and semi‐natural habitat loss and landscape fragmentation. Squamate reptiles are particularly sensitive to habitat structure; however, to date, there is limited information on the importance of hedgerow attributes (microhabitats) and landscape features (hedgerow density) on this group in farming landscapes. Filling this gap is essential to promote agroecosystems favoring biodiversity. To address this, we studied reptile occurrence in an area in western France (Deux‐Sèvres department) that encompasses a diversity of agricultural practices from extensive mixed crop‐livestock to intensive crop production. We monitored species occurrence in 141 transects placed at the base of linear hedgerows, and the structure of each hedgerow as well as the surrounding landscape were described. We found that species occurrence and richness were positively influenced by various hedgerow structure variables including the herbaceous strip margin, the presence of an embankment (talus) and natural ground shelters. Landscape features (high hedgerow density) also positively influence species occurrence by affecting habitat connectivity. Wide hedgerows with enlarged herbaceous strip at their base are at the interface between land sharing (habitats quality) and land sparing (connectivity) strategies within the agricultural matrix and should therefore be maintained or restored whenever possible.