Everything from hoverflies to bats came under the watchful eyes of experts and children at the Woolley Firs Environmental Education Centre in Maidenhead at the weekend.
The centre was playing host to its first ever Bioblitz event, a challenge which originates in America and sees scientists race to find and identify as many species as possible in 24 hours within a given area.
About 40 volunteers from the Berks, Bucks and Oxon Wildlife Trust had plenty of help with the job, as families flocked to join in with the project, which took place from noon to midnight on Saturday and yesterday.
Youngsters took part in pond dipping, used nets in the long grass and helped out with tracking down moths and bats.
The event comes after the centre received a £2,000 grant from the British Ecological Society.
Education manager Lynn Hughes said she was hoping to make the day a regular event so the team can track wildlife at the centre.
She added the young visitors 'didn't want to leave'.
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