Up to 300 jobs will be lost from the Henderson-based company by 2016, the company announced last week.
The company said its workforce had doubled in the previous two years while it worked on the construction of eight Cape Class patrol boats and two high-speed support vessels. But with those projects nearing completion, Austal president Graham Backhouse said changes had to be made.
"The Cape Class contract has been a significant and highly successful contract for Austal and we have delivered vessels of exceptional quality for our customer, the Australian Government, due largely to the skills and expertise of our staff," he said.
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READ NOW"The contract required delivery of a large number of vessels in a short timeframe and we needed to bulk up to meet that demand.
"Now that demand is close to finishing, we need to normalise our employee numbers."
Australian Manufacturing Workers Union" state secretary Steve McCartney said the cuts were symptomatic of a state-wide problem.
"It's another example of the problem being painted across WA," he said.
"That's why we're trying to shock the Government into providing consistent work.
"We're concerned about losing this skill base if the work doesn't come in and then our ability to reboot if it does."
When asked if further cuts were on the cards, Mr Backhouse said: "At present there is enough work to sustain those numbers".
He said Austal was continually on the lookout for domestic and export contracts.