Look out for the blue sea slugs spotted in Wollongong Harbour

Glaucus atlanticus – commonly known as a blue angel, blue dragon, or blue sea slug - found in Wollongong Harbour.
Glaucus atlanticus – commonly known as a blue angel, blue dragon, or blue sea slug - found in Wollongong Harbour.

They might look intriguing, but beachgoers have been warned not to touch any of the little blue sea creatures that have been spotted in Wollongong waters recently.

The Mercury was alerted to the presence of the glaucus atlanticus – commonly known as a blue angel, blue dragon, or blue sea slug – after some were seen washed up on the sand and swimming in shallow water at Wollongong Harbour on Monday.

The biggest one spotted was about the size of a 20-cent coin.

A Wollongong City Council spokeswoman said it had not received any reports of the creatures washing ashore on its beaches.

“We do occasionally have glaucus atlanticus wash up on our beaches,” the spokeswoman said.

“People should always take caution when spotting marine life on our beaches and rock pools.

“There are many marine animals, such as the crown-of-thorns starfish, pufferfish, bluebottles and blue-ringed octopus, that may be found in rock pools and can be harmful to humans.

“This is why we recommend that people follow the ‘look, but don’t touch’ advice when exploring rock platforms.”

The spokeswoman said council lifeguards carried out regular checks at patrolled beaches for marine animals that might have washed up on the shoreline.

Warning signs would be erected if animals such as the glaucus atlanticus or bluebottles are spotted. They will also consider closing a beach if necessary.

Seasoned Eurobodalla marine watcher Jenny Edwards told Fairfax Media in 2016 that the sea slugs “store the stinging cells of bluebottles in the ends of the finger-like projections”.

“They may give a sting but are certainly not life-threatening to us,” Ms Edwards said.