Attempts are being made to safeguard the future of one of Wales' rarest fish, which is currently only found in a single north Wales lake.
The gwyniad are caught in Llyn Tegid and their eggs taken
The gwyniad, which dates back to the Ice Age and is described as similar to a herring, lives in Llyn Tegid near Bala.
Conservationists fear they could be wiped out by pollution, disease or by another fish already in the lake.
Efforts are now under way to move some of the fish to the nearby Llyn Arenig.
Arwel Morris, lake warden at Llyn Tegid, said they hoped the gwyniad, or Coregonus lavaretus, would thrive in their new home although nothing was being taken for granted.
"We can't be certain, but the quality of the lake is the same as here at Llyn Tegid," he said.
The gwyniad eggs are then released into Llyn Arenig
Along with the Countryside Council for Wales and the Environment Agency, conservationists are gathering fish at night, extracting their eggs and fertilising them before introducing them to the other lake.
"The idea is to net the lake during evening hours after dusk - we go out about five or six times, netting and hopefully getting the stock we need," said Mr Morris.
He added that the fish's precarious existence at the lake had been compounded by the introduction of another fish into the lake in the early 1980s.
"The ruffe... is known to eat a lot of the gwyniad eggs," he said.
Gethin Morris, from Snowdonia National Park, said that so far, the operation to preserve the species had been "quite successful".
He estimated they had currently caught around 100 female fish and been able to extract eggs from 11 of them.