Lonely Planet Writer

Melbourne hosts spectacular invasion of giant spider crabs

Sea waters around Melbourne are currently hosting a spectacular invasion of giant spider crabs.

Sheree Marris shots of the giant spider crabs congregating at Port near Australian city of Melbourne.
Sheree Marris shot of the giant spider crabs congregating at Port Phillip Bay near Australian city of Melbourne. Image by Sheree Marris / CC BY 2.0

Every year hundreds of thousands of the crabs follow cooler water by migrating to Australia’s southern shores.

Crabs celebrated in Trinidad and Tobago at Easter.
Crabs need to shed their harder outer shell in order to grow. This makes them vulnerable to predators and could be the reason they are congregating together for protection Image by William Warby / CC BY 2.0

Sheree Marris, an aquatic scientist, captured the enormous crustacean movement in the waters by filming the scene in Port Phillip Bay.

Ms Marris said seeing the huge body of crabs was “so spectacular.”

According to a BBC report, she claimed she was hopeful that what she filmed would help raise awareness of the diversity of Australian sea life.

Although scientists can offer no definitive reason for the mass movement,, they postulate that it may be linked to the process of moulting.

In order to grow, crabs must shed their hard outer shell. Consequently they become very vulnerable to predators such as stingrays and cormorants.

However by crowding together, they provide themselves with a high degree of protection against becoming prey.

Ms Marris pointed out that many people looked on Port Phillip Bay as something of a marine wasteland while she felt it had shown itself to be “really unique and really spectacular.”

She said it showed that Melbourne was the most liveable city either above or below water.