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Surveying at Spot 1

Once you are ready and have recorded the conditions, the survey starts with Spot 1.

Remember to hold your detector up at a 90 degree angle and begin your count at spot 1 with your detector tuned to 35 kHz as illustrated in the video clip.

If you are carrying out a repeat survey you should make sure that you are standing as close as possible to the place described by the previous surveyor.

If you have a GPS system mark down the grid reference of spot 1 so that anyone can easily find it again.

Record any Daubenton's bat activity for exactly 4 minutes (using a stopwatch). Count the number of bat passes for each species.

If you hear bats that sound like Daubenton's bat but you are unable to see them skimming over the water, record the number of passes under "unsure Daubenton's bat".

Optional extra - making audio recordings along walks and at spots

If you are using a heterodyne detector which also has frequency division mode (e.g. the BatBox Duet, Ciel CDB301 etc) and you have a digital recorder or mini disc recorder, then it would be very useful if you can make recordings at your survey spots and also while walking between spots. This enables us to assess the accuracy of species identification using the heterodyne system and also check for additional species recorded at your survey sites. If you would like to help with this aspect of the survey, then instructions can be downloaded here.


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