We’re used to stinger season with blue bottles washing up on our shores, but in some very bizarre recent news, a different kind of ‘blue fleet’ has blown on to our East Coast. 

While ”stinger season” is something you no longer blink an eye at living on the Beaches, this year the East Coast appears to be particularly popular for blue bottles. They’re washing up in their 1000s, with many reports of people bearing the painful brunt of those shocking long blue tails. Images are pouring onto social media of swarms of the little blue bubble creatures washed up on shore and taking over ocean pools. However, this year there’s a shock new development. They appear to have brought some friends with them!!

Blue fleet
Image: Lawrence Scheele

This isn’t your usual blue invasion

Known collectively as the ”blue fleet’ the members most familiar to us are the stinging blue bottles (Physalia utriculus), but this season they’ve brought with them some equally curious creatures sporting a similar blue colouring.

These alien-like lifeforms are normally found floating around in the middle of the ocean but they’ve managed to hitch a ride on strong north-easterly winds to end up on our shores. This is also why they’re dubbed the blue fleet – for their ability to ‘catch a ride’ with the winds.

Blue fleet
Image: Lawrence Scheele

Lawrence Scheele, a final year marine biology student who’s been following the fleet as they head south, captured these intriguing ocean creatures at Long Reef. Since then, his pictures have gone viral on multiple sites including the ABC. The less recognisable members of the fleet that were seen and photographed include blue dragons, and blue buttons.

Blue Fleet
Blue dragon. Image: Lawrence Scheele

According to the ABC:

The blue dragon  is actually a unique nudibranch that floats on the water, upside down. One blue dragon (Glaucus atlanticus) is about 3 centimetres long and has a blue and silver “foot” on its underside, that can be mistaken for its topside.

The other (Glaucilla marginate) is only about 1.3cm long and has a light and dark blue foot and a shorter tail than the bigger dragon.

Blue buttons, like coral, are made up of a bunch of tiny animals called polyps — in this case, they’re all connected to a central disc of keratin that enables them to keep afloat.”

Blue fleet
Two different species of blue dragons feasting on a bluebottle. Image: Lawrence Scheele

Lawrence also managed to photograph by-the-wind sailor and the violet snail. The latter, according to the ABC, “relies on secreting a mucus-covered bunch of bubbles to keep it afloat.”

Violet Snail
Violet snail. Image: Lawrence Scheele

While you might think that similarities between members of the blue fleet mean they won’t hurt each other, that’s not the case. Blue dragons and violet snails actually feed on bluebottles, blue buttons and the by-the-wind sailor, making it a truly a dog-eat-dog-world for them.

While some of these creatures haven’t been so lucky in their lifetime, Lawrence told the ABC he was over the moon with his encounters.

“I was really lucky to have caught them all at Long Reef,” he said. “I think they’re just fascinating, and whenever I post about them fans want to know more.”

What about that amazing blue colour though? Scientists have predicted it’s a defence mechanism for these sea slugs – who are susceptible to attacks on the surface of the ocean and use their colour to camouflage and keep safe.

Blue fleet
Image: Lawrence Scheele

Because they’re so small you may not have spotted then before, but the blue dragons aren’t exactly strangers to Sydney’s beaches. In 2018, they washed up at Freshwater and Curl Curl beaches and made headlines then as well.

While it’s great to see the diversity in our incredible marine life, and as fascinated as people are with these sea slugs, all of us need to stay cautious to avoid any traumatic stings!


If you enjoyed reading about these local creatures you may want to click here and meet Harley Jones, who catches snakes for a living, or click here to read all about another young local photographer who’s making waves


Scroll to Top