Trade unions fear BiFab’s new owners are set to ditch full-time staff roles in favour of agency workers.
They say such a move would damage the struggling yards’ bid to land vital new contracts.
DFBarnes took over the business in April, staving off a closure threat in Burntisland, Methil and the Isle of Lewis, but it has since issued redundancy notices which have cut the payroll to barely a handful of workers.
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The yards once employed 400 people with an extra 1000 contractors on site, but they now sit idle with no orders to process.
GMB Scotland claimed they were “effectively closed” and fears its members are on the way out.
A spokesman said: “It has been the intention of Barnes/Driver all along to sack the full-time union core workforce and then start back non-union agency personnel.
“We believe that this will seriously damage any hope of winning contracts for the yards.”
It said the lack of full-time employees would mean that “government money has been spent creating temporary working instead of full-time working.’’
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Labour in Scotland has now called on Derek Mackay, Finance Secretary, to take action.
The Scottish Government is a minority shareholder in BiFab having invested to keep it afloat three months ago, but has insisted that operational matters are the remit of the parent company.
Jackie Baillie MSP, Labour’s economy spokesman said: “Laying off the highly-skilled core workforce would devastate families and communities - and lead to a loss of skills and experience that would be impossible to replace.
“The SNP government simply cannot be in a position where it has allowed itself to be a facilitator for making skilled workers redundant and replaced with insecure agency work.
“That is an outrage and Derek Mackay must immediately address these reports and take swift action to ensure these skills are not lost for good.”
The Scottish Government said this week it is in regular contact with BiFab.
A spokesman said: “Ministers have made a long term investment. However they do not participate in operational management decisions and staffing levels and office arrangements are a matter for BiFab to consider.
“Ministers were clear at the point new ownership was secured that conditions would remain challenging for the yards and that new contracts would have to be won to secure future work at the yard.
“Ministers have confidence that everything possible is being done to secure new contracts and restore employment to previous levels.”
A spokesman for DF Barnes said it had an ”absolute focus” on finding new work and that it had made “along term commitment’’ to supporting all three yards.
The company said it had adopted an approach of regular dialogue with unions, and informed them some months ago that while there was a gap between projects, it would need to reduce the workforce.
It added: “We believe that the high quality skills of Scotland’s workforce have a critical part to play in our development, but we need to maintain a laser sharp focus on attracting new orders in order to secure everyone’s future.’’