Engineers walked off the job at several major ports. Patrick Stevedores' four port terminals handle almost 45 per cent of all container cargo in Australia. "If this industrial action continues, it is likely to have consequences well beyond our terminal gates," a company spokesman said. "The fortunes of countless businesses, both big and small, and the families and communities they support Australia-wide will be adversely affected without timely access to containerised goods." Patrick Stevedores said national strike action was the first to face the company since the Howard-era waterfront crisis, when 1400 workers lost their jobs in a restructure and were replaced with non-union labour.

"It's no coincidence that this is the first national strike action since 1998," the company spokesman said. "Unfortunately, a very small contingent of the Maritime Union of Australia's most militant officials appear intent on winding back the clock to a time when their power to intimidate and interfere in proper commercial agreements ... was as indisputable as it was unacceptable." Central to the dispute is the issue of job security for existing employees, many of whom have unpredictable work hours, according to the union. "The issue for us has always been job security," MUA deputy national secretary Will Tracey said. "We are not seeking to decrease flexibility and increase costs ... this is not about wages, it is about getting the company to commit to the jobs that are here now, not use them as a pawn in a game to maximise share and asset price."

Patrick executive Alexandra Badenoch​ has strongly criticised the union's local claims at Sydney's Port Botany, for all workers to be made full-time permanent, for 32-hour weeks to be paid at a 35-hour week rate and for higher penalty rates. "Overall we have got a great workforce of hard-working employees, but negotiations have definitely been derailed by extreme claims at Port Botany," she said. "We are passionate about negotiating a constructive outcome." Ms Badenoch said the union's claims at Port Botany would hike labour costs by 53 per cent, but the union said the increase would be just over 10 per cent. Bryce Prosser​, of the Victorian Chamber of Commerce and Industry, warned the strikes were having severe flow-on effects on retail, manufacturing, agriculture and food businesses that rely on the Port of Melbourne.

"Our understanding is that it's having a major impact," Mr Prosser said. "It's throwing people's 2016 shipment plans out of whack and it means their strategies for shipments coming from places like China and internationally have to be put on hold." In the tugboat dispute, which is over an attempt by Svitzer Australia to move all tugboat crew onto a single agreement, a series of strikes have held up shipments in Geelong, Sydney, Newcastle and Melbourne, where Svitzer is sole operator. Strikes have ranged from 24 to 48 hours, but members of the Australian Institute of Marine and Power Engineers have endorsed for up to seven days. All major ports will face tugboat strikes on Tuesday.

The Port of Melbourne Corporation said tugboat strikes had not stopped all port activity because some vessels did not need tugs, and adequate forewarning allowed shipments to be rescheduled. "We are monitoring the situation closely, and urge all parties to reach a resolution," a spokesman said.