Decorator Crabs Dress up to Avoid being eaten

 

IMAGE CREDIT: CRAPPY WILDLIFE PHOTOGRAPHY 

Can be found in shallow waters worldwide using accessories - seaweed, corals and sponges, and sticking them on their shells. - to achieve a few goals: 

 

Blending in:

The decorations often provide camouflage against predators like fish and octopuses. Against the proper background, a decorator crab can blend in perfectly.

• One method employed is tearing a piece of seaweed with their claws, chewing to create a rougher surface to stick to it's shell, and remaining relatively still during the day and freezing around predators

"Everything stays in place thanks to the hooked hairs, called setae, which line their shells and act like Velcro." - Zoologger

IMAGE CREDIT: WIKIMEDIA COMMONS // CC BY-SA 3.0

Repellent:

By using materials that are chemically noxious/smelly to predators, they repel predators by either make themselves toxic or bad to eat

• Accessories made from toxic seaweed, stinging sea anemones 
  

IMAGE CREDIT: WIKIMEDIA COMMONS // CC BY-SA 3.0

"Stachowicz says you can trick these crabs into donning just about anything if you extract a chemical that fish find repellent from their preferred seaweed and paint it on to materials that they normally don't use." - Zoologger 

• They usually reuse the decoration after moulting.

Source: Zoologger: June 2015 - New Scientist