The restoration of phytophagous beetles in species-rich chalk grasslands

This study focuses on the restoration of chalk grasslands over a six-year period and tests the efficacy of two management practices, hay spreading and soil disturbance, in promoting this process for phytophagous beetles. Restoration success for the beetles, measured as similarity to target species-rich chalk grassland, was not found to be influenced by either management practice. In contrast, restoration success for the plants did increase in response to hay spreading management. While the presence of suitable host plants was considered to dictate the earliest point at which phytophagous beetles could successfully colonise, few beetle species colonised as soon as their host plants became established. Morphological characteristics and feeding habits of 27 phytophagous beetle species were therefore tested to identify factors that limited their colonisation and persistence. The lag time between host plant establishment and colonisation was greatest for flightless beetles. Beetles with foliage-feeding larvae both colonised at slower rates than seed-, stem- or root-feeding species, and persisted within the swards for shorter periods. While the use of hay spreading may benefit plant communities during chalk grassland restoration it did not directly benefit phytophagous beetles. Without techniques for overcoming colonisation limitation for invertebrate taxa short-term success of restoration may be limited to the plants only.