Habitat preference and mobility of Polia bombycina: are non-tailored agri-environment schemes any good for a rare and localised species?

Abstract

General agri-environment schemes (AES) have been shown to benefit widespread species, but there is little information on the extent to which rare, more localised, species may also benefit. We tested whether AES options aimed at increasing general biodiversity also benefit a highly endangered moth, Poliabombycina, without species-specific tailoring. We assessed effects on its abundance of two AES options, wide field margins and hedgerow trees, using light traps at the landscape-scale and for mark-release-recapture at the farm-scale. We hypothesized that abundance would be highest at wide field margins and at hedgerow trees, and that if hedgerow trees conferred a positive effect, individuals would be more likely to follow hedgerows than crossing exposed fields while on the move. The results showed that significantly more individuals were captured at sites with a hedgerow tree. Numbers were also higher at wide margins, but this was not statistically significant, and no individuals were caught at field centres. Our study suggests that general options within appropriately designed and implemented AES aimed at increasing overall biodiversity in intensive agricultural landscapes have the potential to not only benefit common, widespread habitat generalists, but some rare and more endangered species as well. P. bombycina serves as an example of how general AES options, existing and novel ones alike, might cater for the needs of rare and localised species. As the precise ecological requirements of most invertebrate species remain unknown, we urge scientists and governments to address the challenge to research and design truly general AES, which options should be able to deliver not only for widespread species but also for the less-widespread counterpart of farmland biodiversity.