Can you figure it out? Confused fishermen spot alien-like ball floating in the middle of the ocean as it's devoured by sharks... but realise what it is when they get closer

Stunned fishermen spotted a gigantic alien-like ball (pictured) floating off the coast of Bunbury, south of Perth on Wednesday before it was devoured by sharks. 


At first fisherman Mark Watkins, 36, thought it might be a boat, or even a stranded hot air balloon. As they headed into shore the fisherman noticed chunks had been bitten out of the eerie sighting and it was no longer inflated.