THE Royal Australian Navy is taking a proactive approach to marine biosecurity by joining forces with the WA Fisheries Department to ensure WA waters remain free of harmful introduced species.
Last year, the Asian green mussel (Perna viridis) was discovered on the hull of HMAS ANZAC during a routine inspection following operations that included port visits in South-East Asia.
The RAN notified Fisheries and together they conducted a thorough dry dock inspection and clean of the frigate and HMAS Arunta, what had been berthed alongside ANZAC for four months, and surveyed submerged pylons and structures at Fleet Base West on Garden Island.
While nothing was found in port, 201 Perna viridis mussels in both juvenile and adult stages were found on HMAS Arunta.
Two months later, four Perna viridis were identified on HMAS Toowoomba and the same procedure was followed, again preventing a potential infestation by a high risk introduced species.
Fisheries principal research scientist Justin McDonald says marine biosecurity has become a bigger issue in the past few years because development along the WA coast means there are many more vessels moving around which considerably ups the risk of introducing something.
Dr McDonald says it costs $1 billion annually to keep mussels like these off hydroelectric pipelines in the Great Lakes, and they have caused a fisheries collapse in the Baltic Sea, devastating the economies of towns dependent on fishing.
If introduced species like Perna viridis are not kept out they can do serious damage to the marine environment and have significant economic and social effects.
“There’s much more awareness and much more transparency in terms of people acknowledging they have a problem and liaising and interacting,” he says.
WA now leads Australia in port monitoring and the RAN has asked Fisheries to maintain an environmental monitoring program around Garden Island.
Fisheries also do risk assessments of incoming ships and require those deemed high risk to be examined before entering WA waters.
“It’s much easier to keep things out than try to eradicate them once they’re in,” Dr McDonald says.
Dr McDonald says the Navy’s policies are “well designed and robust” but realises its limitations and is working with Fisheries to do the best possible job.
He says while eastern Australia has some unwanted species, nothing has managed to take hold in WA despite a few incursions like on the RAN ships.