Conservationists are calling for grouse shooting businesses to be licensed in an effort to stamp out illegal persecution of protected birds of prey.
The calls come as a new crime report details five confirmed cases where raptors were unlawfully killed in Scotland last year.
Details of additional cases that are still under investigation have not been included.
The report, Birdcrime 2017, from the RSPB, is the only one of its kind summarising offences against birds of prey in the UK.
These include shootings of a hen harrier and a short-eared owl on a grouse moor in Leadhills, South Lanarkshire, two nests destructions and one other incident.
The report also revealed there were just four prosecutions relating to raptor crime concluded in 2017, only one of which led to a conviction – for the shooting of a buzzard in Inverness-shire in 2016.
RSPB Scotland says the confirmed cases are just the tip of the iceberg, as many more birds are disappearing but are never found and so do not lead to a criminal prosecution.
These include birds such as golden eagles and hen harriers that have been fitted with satellite tags.
The wildlife charity says illegal killings are threatening the survival of rare raptors and highlight the need for greater regulation of sporting estates.
“Birds of prey are part of the cultural fabric of Scotland, and many of these birds have their UK population strongholds here. Sadly, these amazing birds continue to suffer from illegal persecution,” said Duncan Orr-Ewing, head of species and land management at RSPB Scotland.
“We believe that a step change is now required to tackle illegal behaviours and improve the conservation prospects for birds of prey.
“We support the licensing of driven grouse moors, including sanctions for licence removal where illegal practices are confirmed by the public authorities.”
But sporting businesses claim crimes against birds of prey are at a record low and licensing is unnecessary.
David Johnstone, chairman of membership organisation Scottish Land & Estates, said raptor persecution is “totally unacceptable”.
He added: “Further legislation, such as grouse moor licensing, as demanded by RSPB, is not needed.
“It would be a sledgehammer to crack a nut and would place yet another bureaucratic burden on a sector that delivers widespread social, economic and environmental benefits in rural Scotland.”