Practising avoidance of impact is the only alternative. It can sometimes be possible to rethink the scheme so that an offence is not caused. In cases of demolition the roost will inevitably be lost and bats may be harmed so a license is always necessary if bats are found to be present.
There is no defence from committing offences under the Habitats Directive unless a license is held regardless of how many bats are affected or what species they are. One bat has the same legal protection as 100. Even if it was not known the bats were there prior to the works you would still be at risk of prosecution, as to not check first is now considered as reckless damage. Sentences now invoice £5,000 fines and 6 month custodial sentences.
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