Visitors to Dee Why beach in Sydney have been spending their days wondering what the odd shaped spongy green balls are, and why so many have suddenly appeared.
Beachgoers have dubbed the mysterious balls UFOs (Unidentified Floating Objects).
Local resident Scarlett de Villiers told MailOnline: ‘I picked one up and squeezed it and it was so squishy – but I wasn’t sure if it was alive and was worried I might hurt anything inside.’
Scientists believe the ‘alien eggs’ might actually be a rare form a seaweed that rolls into balls to protect itself from predators, and that very specific wave conditions are required to get them to tumble ashore.
Associate Professor Alistair Poore from the School of Biological, Earth and Environmental Sciences at the University of NSW told the Daily Manly: ‘I’ve seen similar things – sometimes dead sea grass can roll around and form balls like underwater tumbleweeds but that’s made of dead material and these look to be living.’
At least this is a natural phenomenon from Australia that won’t kill you, reported Metro.co.uk.