Bats and construction
|This pedestrian bridge creates a footpath over the Broadland Northway and carries a hedgerow as a foraging route for bats.|
In order to survive, bats require water and insects to eat, hunting areas (foraging habitat), places to hibernate, sleep and raise young (roosts). They also require routes between these different locations (commuting routes).
Bats require a variety of roosting habitats depending on the time of year. In the summer, female bats require a maternity roost to raise young, while in winter, hibernation roosts are required by all bats.
Roost sites vary and can include:
All UK bats feed on insects and so foraging habitats include pastures, woodlands or water. In order to navigate between these areas, bats use echolocation to navigate along hedgerows, woodland edges, treelines and watercourses.
Bats spend the winter hibernating, starting in October/November and typically emerging in March/April. The breeding season begins in June and continues over the summer.
Due to the decline of bat populations, it is illegal to:
- Capture, kill, disturb or injure bats (either deliberately or by not taking enough care).
- Damage or destroy their resting or breeding places.
- Obstruct access to their resting or sheltering places.
- Possess, sell, control or transport live or dead bats, or parts of them.
Any such offence could result in a prison sentence of up to 6 months and an unlimited fine for each offence together with the seizure of wealth gained by committing the offence and equipment used to cause the offence e.g. plant, machinery, vehicles etc.
- Renovation works to an existing building.
- Demolition of a building.
- Pruning or cutting down a tree.
- Repairing or replacing a roof on a house.
- Repointing brickwork.
- Works to lofts including insulation or conversions.
- Removing commuting habitats such as hedgerows or watercourses.
- Treating timber.
- Installation of wind turbines.
 Bats and development proposals
 Visual inspections
Visual inspections might be appropriate for buildings, structures or trees. For buildings, this could include a combination of an internal inspection of roof voids or loft spaces, and an external inspection for potential entry points. It is possible for inspections to be undertaken at any time of year.
If it is not possible to determine whether a roost is present from an inspection, further bat detector surveys are likely to be required. If evidence of bats is confirmed during the inspection, it is likely that further detector surveys would be required to inform licensing requirements.
Bat detector surveys can only be undertaken during the bat active season which is typically between May and September. During that time, several surveys are usually required at dawn or dusk. The surveys will last at least 2 hours.
 Mitigation and licensing
If bats are found to be present and are considered likely to be affected by proposals, it may be necessary to obtain a protected species mitigation licence from Natural England, Natural Resources Wales or Scottish Natural Heritage in advance of works taking place. As part of the licence, a mitigation strategy will be required which will detail how impacts on bats and their habitats will be avoided or minimised wherever possible.
- Altering work methods or timing to avoid bats.
- Creating or improving roosts.
- Creating or improving foraging or commuting habitat.
- Monitoring the roost sites after development.
- Biodiversity offsetting.
- Ecological Impact Assessment.
- Ecological survey.
- Eco-Management and Audit Scheme.
- Environmental impact assessment.
- Environmental plan.
- Environmental policy.
- Great crested newt.
- Japanese knotweed.
- National nature reserves.
- Natural England.
- Preliminary ecological appraisal.
- Protected species
- Protected species licence.
- Tree preservation order.