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Light Levels and Emergence

When you begin the survey there will still be some light in the sky. Different species emerge from their day roosts at different times and not all bats fly in total darkness.

On this survey we are observing species that are large and fast (Leisler's bat) or highly skilled at manoeuvring in flight (pipistrelles).

Birds of prey are bats main predators (apart from cats). These bat species have more chance of out-flying a bird of prey and so they can emerge a little earlier to take advantage of the blooms of insect prey present at dusk.

This video clip shows pipistrelle bats emerging from a roost. When bats emerge from the day roost they often follow certain linear features like hedges or tree lines, keeping close to cover to fly to their feeding sites.

It is often the case that more bats are encountered at certain sections of the route but please do not reverse the route or alter it because of this – it must be done in the same way every time.


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