Project Name: Mount Pleasant

Location: Aspley Guise, Bedfordshire

Tasks: Preliminary Bat Assessment, Bat Emergence Surveys, European Protected Species Licence

Project Overview: Prime Environment undertook a range of bat surveys to support the modification of a planning condition relating to bats and obtained a licence to allow conversion of a barn to residential use.  We also carried out mitigation to remove bats from the barn, and new roosts will be provided in the replacement house.

Prime Environment were engaged by a private land owner to assist with converting a barn to residential use.  Some surveys for bats had already been completed by other consultants, which had identified that bats roost within the barn, but these surveys were out of date.  The client had a planning condition to include a ‘bat loft’ within a proposed summer house, which was not compatible with his plans for the site.

Prime Environment updated the bat surveys at the barn, by undertaking a day time inspection for bats (what we coin a Bat Building Assessment). During the survey we found evidence of brown long-eared bats (their droppings were on the floor) and, using an endoscope, we also recorded a common pipistrelle bat roosting in a timber joint.  In order to provide sufficient evidence to support a European Protected Species Licence (EPSL) application, further surveys were undertaken to record the number of bats using the barn.  This was completed by our ecologists standing outside the barn at dusk and dawn to observe the activity of bats and record their calls on bat detectors (devices which transpose bat’s ultrasound so that we can hear it).

Our results demonstrated that the barn was only used by a small number of relatively common bats, and that the roost was not of significant conservation value.  The original surveys were overcautious and a bat loft in the summer house was not necessary. Our application to modify the planning condition and reduce the mitigation required was successful and we subsequently obtained a licence from Natural England to allow the works to go ahead.

With the licence in hand, Prime Environment excluded bats from the barn’s timber crevices using foam and plastic sheets to create one way valves that allow bats to leave, but not return.  We also oversaw the removal of parts of the barn’s structure to ensure that no bats remained in the building prior to demolition.

The new house will include replacement roosting features for bats so that local bat populations can continue to use the site for years to come.


6 Bridge St, Belper, Derbyshire DE56 1AX

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