Bad weather has stalled the recovery in red grouse numbers in one of the bird's last remaining refuges in Northern Ireland.
The "Glorious Twelfth" shooting season starts on Monday but two wet springs in a row mean numbers on the Antrim Plateau have remained static.
There are about 180 pairs at the remote upland region of Glenwherry, near Ballyclare in Co Antrim, one of six to eight locations across Northern Ireland where the wildfowl can be found.
Adrian Morrow, managing director of the Antrim Estates Company at Glenarm Castle, said: "The recent bad weather means we have been unable to increase the population, the number is static for two years. All the wet weather is not a disaster but we have not been able to increase numbers, so it has been a blow to us."
He said the population had been increased through careful management of the 2.25 hectares of moorland, including burning heather and controlling predators like foxes - until two years ago.
The game bird shooting season runs into November in Northern Ireland and many jobs are supported on the estates and surrounding areas. However, the League Against Cruel Sports has described grouse shooting as animal abuse and said it presented a "gruesome spectacle".
The Irish Grouse Conservation Trust, established by Mr Morrow, is working with Greenmount Agricultural College, the RSPB and landowners to regenerate moor at Glenwherry and promote the development of grouse, curlew, lapwing and breeding waders.
The moor at Glenwherry in the hills above Ballyclare was once well-stocked with grouse, but habitat decline and predation by foxes and crows meant that young grouse had little chance of surviving. By the time the grouse regeneration plan was launched the population was down to just half a dozen pairs.
According to Tommy Mayne, director of the British Association for Shooting and Conservation in Northern Ireland, shooting is worth £45 million to the Northern Ireland economy and employs 2,100 people, generating £10 million a year for conservation work.
He said grouse breeding had been patchy because of the wet weather. "There would not be many shot, perhaps for only two or three days in the season," he said. "The key to increasing numbers is successful habitat management and the control of foxes and other predators like crows."