They might look like something from outer space, but these strange balls are a natural phenomenon right here on Earth.
In September of 2014, locals descended on Dee Why beach for a morning swim and were confronted with a strange sight. Hundreds of green balls had washed ashore overnight.
Around the size of golf balls, the green spheres were likely living balls of algae commonly known as lake balls.
Scientists say bountiful sunshine and rough currents combined to create the perfect conditions for Aegagropilious, the habit of free living algae forming into balls.
The species itself is called Aegagropila linnaei, and is in fact widespread. It’s only this particular growth form, the lake balls, that are rare.
The common name for the lake balls in Icelandic is Kúluskítur. Directly translated it means “round shit” which is supposedly what fishermen used to yell towards the bulky balls when they got caught in their nets in olden times.
In the Japanese town of Akan-ko-han, the balls are known as Marimo and are held in very high regard.
For over fifty years the Ainu people who are indigenous to the island have hosted the annual Marimo festival. The whole town gets dressed up in lake ball attire as the streets fill up with parades and dance shows in its honour.