A bitter row has erupted over the staging of a major event celebrating wild birds at the stately home of a lord who also owns an estate with one of Scotland's worst records for illegally persecuting birds of prey.

The Royal Society for the Protection of Birds (RSPB) in Scotland has come under fire for hosting its popular Scottish Birdfair next month at Hopetoun House, pictured above, on the Firth of Forth near Edinburgh.

Lord Hopetoun is owner of the 11,000-acre Leadhills grouse-shooting estate in South Lanarkshire, which has been repeatedly linked to wildlife crime incidents. Estate gamekeepers have been convicted for laying poisoned bait and shooting an owl, and last October a golden eagle was found shot close to the estate's border.

In the past Lord Hopetoun has denied he is responsible for the management of his estate, which is on long-term lease to a sporting company registered in Delaware, USA. But this is questioned by a land campaigner who has studied the lease.

Ronnie Graham, an expert on birds of prey and a veteran member of the Scottish Raptor Study Groups, is calling for a boycott of the RSPB Birdfair. "I'm just furious at the RSPB's blatant disregard for their members' and general public opinion," he told the Sunday Herald.

"They are riding roughshod over the good work that many Scottish raptor workers do every year under the dark shadow of persecution. Leadhills is an absolute black hole for birds of prey and this has been well documented over the years."

Graham, who runs a gourmet meat and fish business in Dumfriesshire, thinks potential visitors to the fair on May 11-12 should make an "informed decision" about whether to go. "It seems quite amazing that the RSPB, which campaigns seemingly tirelessly to end the poisoning, shooting and trapping of our birds of prey, has chosen this location" he said.

Hopetoun House, east of South Queensferry, has been the ancestral home of the Hopetoun family for more than 300 years. It is owned by a charitable trust, of which Lord Hopetoun is a member. Formerly Andrew Hopetoun and an executive with the former defence electronics company GEC Marconi in London, he now lives in the house and runs the estate. His father, the Marquess of Linlithgow, also lives there in a cottage.

Hopetoun House last year hosted the first Scottish Birdfair, which attracted 4500 visitors and 85 exhibitors. This year the event is backed by the National Trust for Scotland and The Scotsman newspaper.

Last year, a spokesman for Lord Hopetoun said Hopetoun estate had "no role whatsoever" in the management of Leadhills estate. But the 20-year lease to the US Atlantic Sporting company allows Lord Hopetoun to carry out limited "estate management activities", to share gamekeepers and to take shooting parties to Leadhills.

According to the land reform campaigner and author Andy Wightman, Lord Hopetoun also has the power to end the lease if the law is broken. "He has the right to terminate the lease where shooting is not carried out 'in accordance with normal practice on a driven grouse moor'," said Wightman. "That would include any instances of illegal persecution of wildlife."

Last week, Lord Hopetoun's spokeswoman declined to comment, deferring to a statement from the RSPB, which reaffirmed its strong opposition to crimes against birds of prey but said it would not "take issue" with managing land for grouse shooting as long as it was legal and sustainable.

"We are aware that Leadhills estate is in the same family ownership as the privately owned Hopetoun Estate, and have not sought to hide this widely known connection," said RSPB spokesman James Reynolds. He added: "We accept that Hopetoun estate do not condone any illegal practices on their land."