36-year-old Mark Watkins and his father made an astonishing and frightening discoverywhile fishing just south of Perth. Originally, the pair thought that the ball was just a capsized boat or a fallen balloon. But, they realised just in time what it really was.
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An unknown floating object
As they came closer, they realised that what was floating in the water was not a manmade construction, but an organic object.
After nearing the strange ball it became clear: it was actually the carcass of a humpback whale. Gases had formed inside the carcass during its decomposition, causing it to float to the surface. Watkins told The West Australian:
Its stomach was full of gas so it was all bloated up. When we got closer we realised it had to be a dead whale because of the smell.
Dead whale
Images that Watkin took of the whale show the creature's skin cracking and deforming as its body continued to bloat from the gasses.
The danger was that any second the carcass could explode under the pressure of the decomposition gases. Thankfully, the moment they realised, the fishermen were able to flee the scene.
However, the pair noticed that on their way back a shark that had been circling their boat had decided to make a meal of the dead whale causing it to deflate. The 36-year-old continued:
We actually did have a 3.5 to 4m white pointer around our boat that day - it seemed more interested in our boat than the whale.