Don't Let Bats Delay Your Build: What You Need to Know About Bat Surveys

"A bat survey assesses whether bats are present on a site and how a development might impact them," Emma explains. "Since bats are a protected species, planning authorities require bat surveys to ensure compliance with conservation laws."

This applies to any kind of development, including new builds, conversions and home renovations.

Surveys are typically done in two parts:

• A preliminary daytime assessment [which can be done all year round].
• Followed by detailed bat emergence and activity surveys if there’s potential for roosting bats.
• A bat hibernation survey may be required during the winter to establish whether the site is also used by hibernating bats.

Not just anyone can carry out a bat survey. Emma explains, "Preliminary daytime assessments should be conducted by licensed bat ecologists with expertise in bat ecology and survey techniques."

Emergence and activity surveys should be carried out by trained bat surveyors who are experienced in survey methods and using specialist equipment. 

Here’s where it gets time-sensitive.

Bat emergence and activity surveys [watching bats leave or return to roosts] are strictly seasonal. "The optimal survey season in Scotland is from May to September," says Emma. "All first emergence surveys should be completed between 1st May and 31st August, with all surveys finished by the end of September."

If your site requires more than one bat emergence survey, there must be at least three weeks between each visit. 

In short: your project could be delayed for months.

"Unfortunately, if a survey is requested late in the season, it may not be possible to complete all the necessary surveys until the following year. This can delay planning applications and building work, as surveys are required for planning approval."

It can be disappointing to learn there could be a long delay before all required visits can be completed, so planning ahead is critical.

If bats are discovered during a survey, work must pause while a licensed ecologist assesses the situation. Emma explains that mitigation measures might include:

• Installing bat boxes or integrated roost features
• Creating alternative roosting sites
• Adjusting building plans to avoid disruption
   

The aim is always to protect the bats while allowing development to continue — responsibly.

Scotland is home to nine confirmed bat species, including:

• Common and Soprano Pipistrelle
• Nathusius’ Pipistrelle
• Brown Long-Eared Bat
• Daubenton’s Bat
• Natterer’s Bat
• Whiskered Bat
• Noctule
• Leisler’s Bat
   

While some species are more common than others, every one of them is legally protected.

Emma’s number one message is simple: don’t leave it too late, start conversations early especially if you want to stay on track with your build.

"Plan ahead for bat surveys to avoid delays," she says. "And use licensed ecologists for accurate assessments."

She also encourages developers and homeowners to consider bat-friendly design features and to report any sightings to local conservation groups, which helps ongoing research and protection efforts.