Satellite-derived measures of habitat structure perform as well as locally recorded measures in predicting predation on artificial nests in central European agricultural landscapes

Abstract

Ground nesting birds have declined throughout Europe, with the reduction of habitat structure in agricultural areas being a key contributing factor. Habitat structure is vital not only for providing food and suitable microclimates for these species but also limits nest predation. Field assessments of habitat structure have, historically, been the most common way of identifying areas of low nest predation. However, they are limited in their applicability over wide areas due to time, money, and logistics. Remotely sensed measures (e.g., recorded by a satellite) can address these issues. Normalised difference vegetation index (NDVI) is a measure of the ‘greenness’ of an area and correlates with habitat structure. We conducted an artificial nest experiment over three years (2019, 2020, 2023) in Baden, Austria to test the relationship of NDVI to nest predation in an agricultural landscape. Critically, we compared whether NDVI could predict nest predation as well as locally recorded variables (ground cover, vegetation height, etc, ). We report that NDVI performs equally well at predicting nest predation, with predation decreasing with higher values of NDVI, signifying greater habitat structure. This was supported by our finding that predation probability decreased with greater ground cover (a locally recorded variable). Additionally, we found that areas with greater partridge numbers had higher predation and circumstantial evidence that birds are the primary predator in our study area. Overall, our study shows that satellite-derived measures of habitat structure have untapped potential in identifying areas of high nest predation for European ground nesting birds in agricultural landscapes.