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Survey Method
When you have planned your route and walked it during daylight, you are ready to get on and do the survey.

The survey runs annually in August on two separate evenings.

• The first evening should be between
1st – 15th August (period 1)

• The second should be between
16th – 30th August (period 2)

There is a four day period either side of these dates when your survey will still be acceptable. Please leave at least 5 days between each survey night. If you can only manage to do one night then the data will still be useful, especially if it is a repeat site, so please don’t be put off.

Walk the whole transect route covering 10 survey spots.

Choose an evening with good weather conditions. If it is very windy bats will not fly as readily and it is harder to hear them.

If it is too cold this will put bats off as insects will not be abundant. Try and choose a warm evening as bats rarely fly in conditions below 7°C. Bats will fly in light drizzle but ideally it should be dry and forecast to stay dry for the evening.

For your own safety do not survey in high winds, heavy rain or cold. Weather pages online are listed at the end of the tutorial.


planning your survey
bat detectors
support surveying walks
surveying at spots
sign up
after your survey
sign up

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