Identifying high-quality pond habitats for Odonata in lowland England: Implications for agri-environment schemes
Raebel EM., Merckx T., Feber RE., Riordan P., MacDonald DW., Thompson DJ.
1.Agricultural intensification has contributed to severe declines in odonate (dragonfly and damselfly) populations. The objective of our study is to benefit current measures for the conservation of odonates by establishing the conditions favourable to Odonata and focusing on ponds within agricultural land. 2.Our landscape-scale study used exuvial counts and habitat measurements from 29 ponds across a catchment in England, over 3years, to determine key factors affecting odonate abundance and species richness. 3.Ponds dominated by floating and submerged vegetation were the most transparent, supported the highest abundance and species richness of exuviae, and were always fully or partially surrounded by buffer strips. Ponds lacking vegetation were turbid, yielding no exuviae even if they were buffered. English agri-environment schemes (AES) currently support pond and buffer strip creation and management. 4.Abundance of exuviae was higher in recently created ponds compared to older ponds, whereas ponds that had dried out the previous summer had fewer exuviae. 5.Species richness of exuviae decreased with increasing distance to the nearest viable pond, falling by more than 40% for distances over 100m. 6.We conclude that odonate conservation would be more effective if AES would consider the spatial scale at which ponds are created and the location, type, and quality of ponds targeted for buffer strips. © 2011 The Royal Entomological Society.