Conference carried three motions calling for Prospect to put its resources behind the campaign to highlight the sector's importance and lobby all political parties to try and get the spending cuts reversed.
Georgina Jones (British Library) moved a motion describing how the sector has been decimated, despite the fact that heritage accounts for 7% of the British economy. Museums, libraries and galleries face another 5% funding cuts from 2015 and the prospect of more cuts beyond this, causing irreparable damage.
Yet they are a major draw to tourists and a source of enjoyment, education and wellbeing for all, she said. "In the British Library I see it every day. People come from across the world to use our collections and the way funding is being cut automatically impacts on the way people can use them."
From the Royal Commission on the Ancient and Historical Monuments of Scotland, Angela Gannon echoed the value of heritage to the economy and health and wellbeing of communities and stressed the importance of Prospect bringing together members in different workplaces to campaign on collective concerns.
"Did you know that 28% of adults in Scotland, together with 14 million tourists, visited a heritage site last year? Or that the National Museum in Edinburgh is the most visited attraction outside London and that Edinburgh Castle is Scotland's top paid for attraction, with a record 1.4 million visitors last year? Strange then that when funding in the sector is going down its economic contribution is going up."
Prospect's main concern was sustainability in these times of major change, she said. Her own organisation was facing merger with Historic Scotland in 2015 to create Historic Environment Scotland while in England, English Heritage was to be split in two.
"It is clear that the constraints of delivering more for less have had a detrimental effect on staff and their morale," she said. "Staff are not being replaced, recruitment is compromised and succession planning and professional development are long forgotten aspirations."
Prospect's survey of members in advance of the union's recent seminar "Heritage in a Cold Climate" had strongly highlighted these issues.
From Scottish Natural Heritage, Graeme Walker said: "A government that believes that cuts are the cure looks on its heritage organisations as a soft target." Many of those working in the sector were there for vocational reasons, an extension of their personal and academic interests.
Prospect's own survey results were not encouraging.
"We know we can draw on the support of the public when we catch their attention," he said. "For example, as of last night the ongoing petition opposing cuts at Kew Gardens has attracted more than 89,000 signatures. I urge those of you who haven't to sign it today.
"In isolation our organisations don't command much attention from the press or the political class. Only together, in strength, do we stand a chance of getting our message across."
In debate Lin Dafis (Wales Heritage/Cangen Treftadaeth Cymru), who works at the National Library of Wales, said his members, too, were experiencing high stress levels and low morale as a consequence of spending cuts.
Cuts in core funding and inept management responses were having an effect on people's personal lives. There was an additional professional impact on the collections curated by members.
Last year a fire at the National Library of Wales had put Prospect members in physical danger. Building maintenance at the library was needed, costing three years' worth of its annual budget, but it was unlikely to happen for a long time.
In the past three years, people representing over 200 years' worth of specialist expertise and knowledge had left the library without being replaced.
Ian Varnes (BT Mid Yorkshire) said: "Our past is our future." As a country and a union it was vital to inspire the next generation of young workers. "Our museums, collections and the people who work in them provide that inspiration."
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