Workers at almost a dozen Scottish universities will take five days of strike action this week as part of an ongoing rowover pensions and pay and conditions.
It is the third round of walk-outs from University and College Union (UCU) members this academic year after fury over pension cuts.
This week's action follows 10 days of walkouts between February 14 and March 2 and a three-day strike in December.
The union said Universities Superannuation Scheme (USS) pension cuts "forced through" by university employers will see 35% slashed from a typical member's guaranteed retirement income, and it is demanding employers revoke the cuts and re-enter negotiations.
In the pay and working conditions dispute, the union is asking for a £2,500 pay rise for all university employees as it estimates wages have fallen by more than a quarter (25.5%) in real terms since 2009.
UCU general secretary Jo Grady said: "Vice-chancellors and principals across the UK have the power to end these disputes. The money is there to pay staff properly, tackle punishing working conditions and reverse pension cuts that will devastate retirement incomes.
"Instead, university bosses are choosing to sit on reserves worth tens of billions of pounds and make their own staff suffer. That's why we are out on picket lines yet again.
"By continuing to ignore the longstanding and serious concerns of staff, principals are not only pushing their own workforce to breaking point, but also doing serious harm to the future of higher education and preventing it from being the best it can be."
In the pay and working conditions dispute, the union is also demanding an end to race, gender and disability pay injustice, a framework to eliminate zero-hours and other insecure contracts, and meaningful action to tackle unmanageable workloads.
Those walking out on Monday are members at the universities of Dundee, Edinburgh, Glasgow, St Andrews, Stirling, Strathclyde and Edinburgh Napier University, Glasgow School of Art, Heriot-Watt University, the Open University and Queen Margaret University.
Members at the Open University are also taking two extra days of strike action because the teaching model is different to a standard university week, with the bulk of tutorials taking place during the weekend.
UCU members there will also be on strike on Saturday March 26 and Sunday March 27.
Members at some institutions are taking action only on the pensions issue, some only over the pay and working conditions dispute, and some on both.
A USS spokesman said: "We understand the concerns of USS members, but the fundamental truth is that the price of promising a set, inflation-protected income for life in retirement - paid no matter what happens to the economy or the higher education sector in future - is much more expensive today than in the past.
"The decisions made by the joint negotiating committee respond to the challenges presented by long-term economic and demographic trends by slowing the pace at which USS pension promises build up in future.
"USS remains one of the relatively few private DB (defined benefit) pension schemes in the country still open to new members and still offering valuable 'guaranteed' benefits to its members."
A Universities UK spokesperson, on behalf of USS Employers, said: "Taking university staff out on strike again will not remove the need to reform USS to ensure it remains affordable for members and employers.
"The package of reforms proposed by employers has now passed the joint negotiating committee and the USS Trustee Board, and will be implemented from 1st April 2022.
"February's industrial action did not achieve the outcome UCU intended, and data gathered by Universities and Colleges Employers Association (UCEA) suggests turnout on picket lines was even lower than before, with limited disruption to students.
"With news of more strikes and yet another ballot, reasonable onlookers will conclude the union has an ideological fixation with strike action and is determined to pursue it, no matter the cost. Since 2019, an average member of staff earning £55,000 per annum taking strike action has forgone over £4,800 in pay deductions, to no avail.
"Scheme members should ask themselves whether they are willing to sacrifice even more to pay higher pensions contributions based on UCU's unsubstantiated view that another valuation will yield a better outcome.
"Employers have repeatedly made clear that current contributions are at the very limit of affordability, and a majority of those responding to a consultation on UCU's proposal for higher contributions rejected it.
"Recent government announcements underline the wider financial uncertainty universities are facing, and with the 2020 valuation now concluded, it is time to look forward and identify lasting improvements to USS that can be made ahead of the next valuation."
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