BSG Ecology was delighted to receive the inaugural award for best roost mitigation project from the Bat Conservation Trust for our work at Totterdown Barns in Gloucestershire. The award not only recognises BSG’s role in delivering this project, but also that of the architect Mathewson Waters and the developer Rivar Ltd. Effective collaboration was essential to arrive at a winning design for the conversion to residential use.
The judging panel for the award included a number of bat conservation experts from the Bat Conservation Trust, Vincent Wildlife Trust and specialist independent consultancies. BCT said “The judges were impressed by the sensitive nature with which the works were carried out to avoid disturbing bats and how the building was designed to accommodate both the bats and people in a variety of ways.”
Senior Ecologist Karen Lunan, who has overseen the implementation and monitoring works, said, ”It has been a privilege to be part of this innovative project and exciting to see the emerging results of the post-conversion monitoring programme and to experience first-hand the success of the mitigation design.”
Prior to the conversion of Totterdown barn, we recorded the presence of a maternity roost of Natterer’s bats. In order to allow the barn conversion to proceed whilst protecting the bat roost, a European Protected Species (EPS) licence was secured and the barn was modified to create a dedicated bat loft in the location of the retained roost. The remaining parts of the barn were developed for residential use.
As part of the EPS licence, a three year monitoring programme was developed to assess the success of the mitigation. Three monitoring visits were undertaken in the first year after the commencement of the conversion works, and two monitoring visits were undertaken in the second and third years. In the first year of monitoring, conversion works were stopped during the bats’ maternity period to allow them to return to the modified roost undisturbed.
The monitoring programme involved counting bats emerging from the modified roost within the barn at dusk, at both the start and end of the maternity period. This allowed a relative measure of breeding success, by comparing numbers of adults at the start of the maternity season with numbers of adult and young at the end of the maternity period.
The results show that the maternity roost re-formed during each year of monitoring, in similar numbers to those recorded pre-conversion. Following on from our monitoring programme under licence, the barn continues to be monitored by local volunteers on a yearly basis. This is providing continuity of data and has also led to the discovery of a new roost of soprano pipistrelle bats in one of the adjacent converted annexes.
For more information on the project design and monitoring, see the Totterdown Farm Barns Project Profile. If you would like to discuss the project further, or any other roost mitigation issues please contact one of our offices.