Pink Tank Scuba was diving near Blairgowrie Pier in Port Phillip Bay, Victoria, Australia, when they saw something odd.

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.

Nope, definitely not coral.

Nope, definitely not coral.

It’s a giant pile of NOPE.

It's a giant pile of NOPE.

This is fascinating, but it may convince you to stay on dry land.

At this time of year, spider crabs usually gather for a mass migration and molt.

However, seeing such a spider crab pyramid seems to be pretty unusual (even for regular divers in the area). According to Hirschfield (via Grind TV), “The behavior I observed was really just a lot of climbing and a few scuffles as crabs got in each other’s faces…A few of the crabs in the pyramid were also adorning themselves with sponges becoming decorator crabs, which is a camouflage mechanism.”

Not only that, but these pyramids don’t last very long.

So, these divers were just a lucky few who were able to witness such a large, skin-crawling event.

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