Anti-fishfarm campaigners are claiming a "landmark victory" after the Scottish Information Commissioner instructed ministers to release figures for the number of seals shot under licence at salmon farms.

The Scottish Government has withheld the information, claiming its disclosure "would substantially prejudice public safety" in particular that of fish farm workers, netsmen and their families. But the Global Alliance Against Industrial Aquaculture appealed twice to the information commissioner Rosemary Agnew.

Now the seal killing forms submitted by salmon farms for the years 2013 and 2014 have to be published by August 21, although the Scottish Government has 42 days to exercise a right of appeal to the Court of Session on a point of law.

Salmon farms and netting operations can apply to the Scottish Government's agency Marine Scotland for a licence authorising shooting of a limited number of seals within a specified area and period.

The Scottish Government publishes a summary of the total seal licences granted per area annually.

Ministers had told Ms Agnew that a campaign of direct action against the shooting of seals had developed on the basis of this available information, as highlighted on the campaigners' Facebook pages. This direct action commenced in April 2014 at Gardenstown on the Moray Firth, extended to the Montrose area in May of that year, then to the north coast in August, with the main focus on one salmon netting company. This is a reference to Montrose-based Usan Salmon Fisheries.

The Scottish Government submitted that aggressive confrontation was being pursued by campaigners and by a number of hunt saboteur groups, which carried a serious potential risk to public safety.

Scottish Government evidence said: "A number involved masked campaigners confronting marksmen who were in the possession of firearms, with the stated intention of standing in front of their guns. The ministers considered that it was hugely fortunate that, for the moment, great restraint had been shown by those confronted in this way and that such potentially explosive incidents had not resulted in more serious consequences."

However the commissioner has concluded "there was insufficient evidence from ministers of an increased threat to public safety if the information about seal shootings at salmon farms carried out under licence was disclosed." She ordered the information be disclosed.

Don Staniford, the controversial Director of the Global Alliance Against Industrial Aquaculture, said "This is a landmark victory. Today's decisions are a shot in the arm for freedom of information and a shot across the bows of the bloody Scottish salmon farming industry. Now the public will be able to boycott salmon from lethal salmon farms. It is shameful that the Scottish salmon farming industry continues to kill seals and shocking that supermarkets still source seal-unfriendly farmed salmon."

John Robins, Secretary to the Save Our Seals Fund said "We welcome the decision to release this information as it is vitally important for the public to know which salmon suppliers are killing seals in order to make ethical consumer choices when shopping. When you buy Scottish salmon you pay for bullets to shoot seals."

Animal welfare charity OneKind also welcomed the news. Policy Director, Libby Anderson said claims that killing a seal was only a last resort when all non-lethal methods have been tried and failed, needed to be independently monitored.

A Scottish Government spokeswoman said the Scottish Government had received the commissioner's decisions, adding :"We are currently considering their terms."

Scott Landsburgh, Chief executive of the fishfarming industry body Scottish Salmon Producers' Organisation said:

"The number of seals shot by salmon farmers has declined dramatically over recent years. We have championed deterrence techniques that are designed to keep seals away from our fish, and shooting is always a last resort."

Usan was approached for a comment, but did not respond.