It was in 2002 that a single male greater mouse-eared bat (Myotis myotis) was discovered overwintering in a cave in Sussex, 10 years after the species had officially been declared extinct.
But following conservationists' initial excitement, hope for Britain's rarest mammal slowly dwindled as the male spent another 20 lonely winters there, all by himself.
Excitement renewed in 2023, as another greater mouse-eared bat was discovered and the two bats hibernated in Sussex in underground railway tunnels.
However, neither of them were spotted in 2024.
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Now, hope for the species has renewed as two new individuals were found in January. During a hibernation survey, members of the Sussex Bat Group found a greater mouse-eared bat in South Downs National Park. It was an adult breeding female.
Meanwhile in Kent, a new individual has also been found in Dover Castle, the first one to be found in the county for 40 years. Its gender is yet to be determined.
The bat in Dover Castle was discovered by ecologist Claire Munn along with members of Kent Bat Group. Claire has been monitoring heritage sites for bats in Dover since 2018.
Claire told the Bat Conservation Trust: "I was leading a team of fellow volunteers for our regular hibernation surveys. We were gobsmacked to find a very large bat, which looked somewhat like a Natterer’s that had overdone it at the gym and taken too many steroids!
"ID books at the ready, we surmised it was probably a greater mouse-eared bat. We have since had that confirmed.”
Myotis myotis is the largest bat found in Britain, weighing around 30g. It is also found across most of Europe, roosting in caves, mines and cultural buildings.
Conservationists are unsure if the new British individuals have been born in the UK, or if they have migrated from Europe to overwinter here.
If you have found a bat in need of rescue, or need information on roosting bats, call the National Bat Helpline on 0345 1300 228.
Main image credit: Getty Images