Shame-faced crab has nothing to hide about

By Bec Crew | November 27, 2014

It may look like its hiding its face out of embarrassment, but this crab has everything to be proud of

Contributor

Bec Crew

Becky Crew is a Sydney-based science communicator with a love for weird and wonderful animals. From strange behaviours and special adaptations to newly discovered species and the researchers who find them, her topics celebrate how alien yet relatable so many of the creatures that live amongst us can be.

I DON’T THINK I’ve ever loved another crab as much as I love this crab right now. He’s so embarrassed he can barely even look at us. He’s so ashamed that he has to cover his face with his two humungous front pincers. Don’t feel bad, shame-faced crab, we don’t care what you did; you’re just a crab.

Found at depths of up to 50m below the surface of the Indo-Pacific, these large crabs range as far as Madagascar to west, Japan to the north, and throughout Indonesia, Papua New Guinea and New Caledonia a little closer to home.

Despite their looks and their funny little name, shame-faced crabs (Calappa calappa) are no victims. These highly armoured creatures are like walking tanks, their 15cm-long, burnt-caramel-coloured carapace acting as the perfect cover from predators until they have a chance to bury themselves right into the sand. Watch the video below, it’s almost a little creepy how it inches deeper and deeper into the ocean floor, until all that’s left is a pair of beady eyes and the upper edges of its jagged pincers, looking just like a monster face peering up at you.

Shame-faced crab hides away

Shame-faced crabs don’t have to worry too much about predators, but keep themselves hidden during the day all the same. At night they turn to hunting, targeting little mollusks such as clams, oysters and sea snails. While hard-shelled prey like these present a challenge to many would-be predators, the shame-faced crab has evolved to deal with them expertly.

Of its two huge, meaty pincers, the right one is perfect for cracking into its prey’s tough outer shell. It’s equipped with a single, specially curved tooth that works with the flat surface of the pincer just like a can-opener to cut into its prey. Then the left pincer, which is longer, smaller, and sharper, takes over to extract the flesh from inside.

Being elegant about how you eat your dinner is nothing to be ashamed about, shame-faced crab. Just because the rest of the ocean is filled with barbaric rubes that wouldn’t know a utensil if it landed on them. Chin up, little man!