A bittern has been heard "booming" on the Isle of Wight for the first time, in what conservationists say is a mark of success for a wetland restoration scheme.
The distinctive mating call was heard at RSPB Brading Marshes, a recently restored wetland which stretches from the village of Brading to the sea at Bembridge Harbour on the island.
It is the latest sign of success for the elusive bird, whose numbers fell to just 11 "booming" males in 1997, but is now recovering with the help of intensive conservation efforts.
Bitterns are secretive and spend most of their time living within dense reeds, making them hard to count, but the loud and distinctive booming call of breeding males is used as a measure of the population.
Despite their revival, there are still less than 200 bitterns at fewer than 75 sites in the UK, making the first record on the Isle of Wight something "remarkable", the RSPB said.
It is also a mark of success for the restored marshes, the wildlife charity said, as attracting breeding bitterns is one of the best indicators of successful wetland management.
It is hoped the booming call of the male will manage to attract a mate, and the pair will breed on the reserve - which would be another first for the island.
Keith Ballard, warden of RSPB Brading Marshes, said: "Hearing a booming bittern on a wetland reserve is like receiving a Michelin star as a restaurant; it's one of the highest marks of success we could hope for.
"Bitterns have very selective habitat needs, and to attract them you need a truly thriving ecosystem.
"The work we have done to manage the reserve for insects, fish, reptiles and mammals, as well as birds, now means we have one of the most UK's most sensitive species choosing the Isle of Wight as its home."
Staff at the nature reserve will monitor the bird over the coming weeks.
Bitterns, heron-like birds which were once prized in medieval banquets, were considered extinct as a breeding species in the UK by the 1870s.
They recolonised the UK in the early 20th century, with a peak of around 80 booming males in the 1950s, but then saw numbers slide till they were facing extinction again with just 11 males mainly in Norfolk and Suffolk.