Bat Surveys

Bat surveys are an essential part of the planning process for many development projects. They help identify the presence of bats and their roosts, ensuring appropriate measures are taken to protect them throughout development.

Why are bats surveyed?

All bat species are European Protected Species under the Conservation of Habitats and Species Regulations 2017 (as amended), with additional protection under the Wildlife and Countryside Act 1981 (as amended). It is an offence to damage or destroy roosts, disturb bats, or obstruct access to roost sites. Several species are also Species of Principal Importance (SPIs).

Bats commonly roost in natural habitats such as trees, cliffs, and caves. However, they frequently use buildings and other man made structures that mimic these environments. These sites may be used for day roosting, breeding, mating, or hibernation.

When do I need to have bat surveys?

A Preliminary Roost Assessment (PRA) is required when a proposed development may affect or destroy potential bat roosting sites. This is typically part of the planning application process and can be carried out at any time of year.

In many cases a PRA is included within a Preliminary Ecological Appraisal (PEA), particularly where protected species may be impacted.

The results of the PRA determine whether further bat surveys are needed based on site features and any evidence or likelihood of bat activity.

Negligible

A structure or tree with negligible suitability requires no further surveys.

Low

A structure with low roost suitability requires one dusk emergence survey between May and August.
A tree with PRF-I requires no further surveys.

Moderate

A structure with moderate suitability requires two dusk emergence surveys between May and August.

High

A structure with high roost suitability or a tree with PRF-M requires three separate dusk emergence surveys between May and August.

Further surveys include:

Ground Level Tree Assessments (GLTAs) are a detailed inspection of trees to identify features such as cracks, cavities, and loose bark that may provide roosting opportunities for bats.
Dusk Emergence Surveys are undertaken to confirm the presence or likely absence of bats emerging from a structure or tree. They help identify roost locations, species, and levels of activity.
Bat Activity Surveys use ultrasonic recording equipment to detect, identify, and sometimes quantify bat activity within a site. They assess foraging, commuting, and potential roosting behaviour.
Winter Hibernation Surveys may be carried out to confirm whether bats are using a site for hibernation.

What does Abrehart Ecology offer?

At Abrehart Ecology we offer professional, skilled, and efficient bat survey work. We undertake in-house fieldwork and expert report writing with our licensed ecologists.

We carry out all the bat surveys listed above, from PRAs through to further survey work as required.

We use high quality infrared camera equipment and acoustic recording devices to provide clear evidence for reports and submission to planning authorities.

Once the potential for bats has been established, we can facilitate a Low Impact Class Licence (LICL) or a Full Bat Mitigation Licence, depending on the situation.