Volunteers sought for a large scale citizen science project to identify the types and distribution of bats in the islands.
The Bailiwick Bat Survey will take place across Guernsey, Alderney and Sark.
Volunteers are needed to record soundings on a patch of land measuring 500 metres square and each island has been divided up in this way.
Individuals will collect a special sound pole which automatically records a bat's call to a memory card each time it flies past. Bats calls are inaudible to the human ear.

Two separate sets of recordings are made over a four day period, between April and July, and July to October.
The sounds are uploaded to a website and analysed and the results sent to the volunteer within hours.
Last year, a new species of bat was discovered in the Bailiwick, the Soprano Pipistrelle, taking the total number of different bats in the islands to 13.
Phil Atkinson from the British Trust for Ornithology says the project will connect and engage the community with an aspect of nature that is generally poorly known about:
"Using citizen science in this way, it will help raise awareness of what bats do for us and why it is important to conserve them.
The success of this project is dependent on volunteer participation and as the survey runs from the start of April until the end of October, there is plenty of time to take part."
Emily Coule from the States says bats are a protected species:
“Bats are safeguarded under the Agreement on the Conservation of Populations of European Bats (EUROBATS).
By signing up to this agreement, Guernsey has committed to protect bats through monitoring, legislation, education, conservation measures and international co-operation."
Anyone interested in volunteering can find out more at www.bats.org.gg

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