Boreal Peatland LIFE -project – The effects of drainage and restoration on mire butterfly abundance and species richness

In Finland peatlands have been extensively drained for forestry, agriculture and peat production, and this drainage has caused significant population declines of mire butterflies. Here we report the effects of drainage and restoration on total abundance and species richness of mire butterflies and other butterfly species and also on abundance of each individual species from a monitoring scheme initiated in the Boreal Peatland Life-project. We found that both abundance and species richness of mire butterfly species were lower in drained sites than in pristine sites confirming that drainage has a negative influence of these species. We also found an encouraging result that the number of mire butterfly species increased already few years after restoration in the restored sites. This project provided evidence that restoration is successful and increases number of mire specialist species in restored mires. The monitoring setups established during Boreal Peatland Life-project form an interesting monitoring opportunity to increase knowledge about the long term effects of restoration and monitoring. Every effort will be made to continue the monitoring to allow us to judge the long term impacts of mire restoration.