An osprey chick has gone missing from its nest in the Tweed Valley.
One of the Tweed Valley ospreys has not returned to its nest
Volunteer observers were delighted to see two of the birds make their first flight recently.
However, they are growing increasingly concerned that one of them has failed to return to its nest - which they say is highly unusual for younger birds.
Community Wildlife Officer Diane Bennett said they were "holding their breath" and hoping that nothing sinister had happened to the osprey.
The absence of the chick is worrying volunteers who run viewing centres in Glentress Forest and Kailzie Gardens, near Peebles.
"It's brilliant that the chicks have taken their first flight and we are all very excited at this," said Ms Bennett.
"It is normal that after the first flight young ospreys will return to the nest or hang about the nesting site, just so that they feel reassured.
"Unfortunately we've not seen both chicks back so we are holding our breath that nothing sinister has happened to our missing youngster.
"We are hopeful that the parents are looking out for it and providing the chick with lots of food and guidance."
There are currently five chicks in the Tweed Valley osprey project, two on the main CCTV viewing nest and three on the back-up viewing nest.
The project is part of a three-year celebration of the 50th anniversary of the return of ospreys to breed in Scotland in 1954.