Dormice and their habitats are protected by law
A hazel dormouse has been spotted in Sussex leading to plans to carry out a wider survey to find the rare animals.
The tiny creature was seen at Arundel's Wildfowl and Wetlands Trust where staff checked for dormice ahead of scrub management work.
Dormice are nocturnal creatures which weigh about the same as two £1 coins.
Emma Hutchins, biodiversity manager, said there was "anecdotal reference to them historically" and staff checked for dormice as a precaution.
She said: "Much to our surprise, on the first day of the survey a Dormouse scuttled out of one of the special tubes we had erected.
"Now we have established a presence, we need to apply for a licence before we can continue to expand the survey."
She said the find was a first for the trust because none of its five reserves across the UK have the species on site.
Dormice and their habitats are protected by law.