More than a quarter of jobs at the National Trust for Scotland are at risk as part of a wide-ranging restructure designed to tackle a £47m "conservation backlog", the charity has said.
The charity, which has 540 full-time staff, said that up to 142 jobs were at risk as part of plans to make savings of £4m a year.
The plans include significant changes at the trust’s headquarters in Edinburgh, where the majority of the 142 at-risk posts are based.
Forty-two staff at the headquarters will be relocated as part of the reforms, and 68 new posts will be created, the charity said.
Only core national services would be based at the headquarters in future, the charity said, and a voluntary redundancy scheme would be put in place.
The trust, which has 350,000 members and manages 129 properties, said the reforms were part of an attempt to reverse falling visitor numbers.
The reforms come after a review of the 85-year-old charity by Sir Moir Lockhead, its chair, Simon Skinner, its chief executive, and the board of trustees.
A £17m investment programme will also run over the next three years, with a number of properties benefiting, including Culzean Castle in Ayrshire and Brodie Castle in Forres.
According to the Office of the Scottish Charity Regulator’s website, the National Trust for Scotland had an income of £46.8m for the year ending 28 February 2015, compared with expenditure of £49.2m.
The changes to the trust’s workforce will also devolve expertise, decision-making and planning to properties at regional and local levels, the charity said.
Skinner said: "While the trust has achieved stability in the last few years, we have choices to make if we are to move forward and face up to ensuring our heritage remains relevant and engaging in an era of ever-more demanding, digitally-savvy generations.
He added: "This will allow us to address the £47m conservation backlog that has been a long-standing barrier to our ambitions.
"It’s essential for every organisation to adapt to the challenges it faces. That’s what we’ve done, and the resulting changes will bring immense benefits to the care of Scotland’s heritage, our members and the people of Scotland."
The trust has now opened a 90-day consultation with its recognised trade union, Prospect.
Ian Perth, negotiator at Prospect, said the trust’s announcement was a "devastating blow to Scotland’s heritage sector".
He said: "Our members are already significantly stretched and continue to do valuable work for the charity in such difficult times.
"We are concerned that the trust’s proposals rely heavily on replacing full-time staff with contractors. Although a move like this can show short-term cost reductions, they risk damaging the trust in the long term."