Pink Tank Scuba was diving near Blairgowrie Pier in Port Phillip Bay, Victoria, Australia, when they saw something odd.
Every year for short time thousands of spider crabs come together in Port Phillip Bay, Australia. They seem to appear out of nowhere and from April to July local divers are constantly asking each other if they have heard anything about the spider crabs this year.
Spider crabs can be found almost anywhere in the bayand are sometimes difficult to see because of their ability camouflage themselves with sponges. However they commonly come together in the southern part of the bay to moult their shells.
It is still unknown as to exactly why the crabs aggregate, it was once believed it was to mate, however very few animals are observed mating during this time.
From a distance, it looked like debris or possibly coral…but no, it was over 1,000 spider crabs crawling over each other to make a huge pyramid on the ocean floor.
This is an easily observed spectacle of Nature, often in shallow water near piers such as Rye pier. Check with your local dive shop on a regular basis around April to July and keep an eye on internet forums to find out when they arrive.