The effect of slugs on seedling recruitment and community compositionin upland hay meadow plant communities
Abstract: Restoration of species-rich upland hay meadows is a target of the EC HabitatsDirective and the UK Biodiversity Action Plan for Upland Hay Meadows. Previous restorationresearch has predominantly focused on the optimum farming management regime, andinteractions between the above ground vegetation and the soil microbial community, with littleattention being paid to the role of grazing invertebrates. Slugs have the potential to affectseedling recruitment and community composition through the selective removal of favouredspecies at the seedling stage. A mesocosm experiment was designed to test this hypothesis over athree year period. Results showed a significant effect of slug grazing on community compositionone year after sowing, with evidence of selective grazing on Rhinanthus minor L. (Hay rattle)(Orobanchaceae) seedlings. The selective removal of R. minor, a hemi-parasite and keystonespecies, by slugs, is of critical interest to the restoration process as R. minor is used as amanagement tool to reduce the dominance of competitive grass species in species-poor meadowsthat are targeted for restoration.