A beachgoer's curiosity was triggered after spotting a colourful creature he didn't recognise at a popular tourist spot in Victoria.
The man snapped several pictures of the disc shaped creatures strewn across the rocks and turned to social media for answers.
"Could anyone please tell me what this is? Heaps of them at Eagles Nest Beach," he wrote on Facebook.
Misleading social media speculation
After many online shared they had spotted similar looking creatures, the misleading consensus in the comments section was that it was a bluebottle, or a Portuguese man o'war as it is known in the northern hemisphere.
However, it was confirmed the pretty marine animal spotted washed up on the beach were in fact velella (or by-the-wind sailor as they are commonly known) which in recent years have began to frequent Victorian shores due to warmer water temperatures.
“Twenty to 30 years ago it would probably have been uncommon to see them. Nowadays it's certainly not," Professor of Toxicology, Jamie Seymour, from James Cook University told Yahoo News Australia.
He explained that you wouldn't be hard pressed to find bluebottles nearby after spotting a by-the-wind sailor as the species have similar diets and tend to live in warmer waters, but there is one important distinction between the species — their sting.
By-the-wind sailors have mild stings
Professor Seymour explained that the sting of a by-the-wind sailor "doesn't compare to a bluebottle" and only causes minor pain at the sting site in comparison, but confirms you would definitely know if you were been stung by one while out and about.
"Hundreds, if not thousands of people are stung by them in Sydney every year," he explained.
By-the-wind sailors are also differentiated from bluebottles as they are known to be either right or left handed sailors depending on which direction their semi-circular fin has grown on their body.
This unique genetically fixed feature is where they get their namesake from and is an important evolutionary trait which enhances the survival of the species.
"Some of the population will go left, the others will go right. If the winds blowing to push everybody towards the beach, half will go offshore and half will go onshore," Professor Seymour explained.
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