Watch Decorator Crabs Get Decked Out in Camouflage

When the perfect accessory is a matter of life and death.

If you’re a crab and want to keep predators at bay in Bodega Bay, California, the strategy is to dress up to blend in—some algae, a sponge or two, maybe even an anemone. KQED, San Francisco’s PBS affiliate, takes us underwater with this video of decorator crabs picking out the perfect bits of camouflage to help them avoid hungry fish and octopuses.

Decorator crabs, which are found all over the world, have special hooks on their upper shells that work a bit like Velcro and keep their disguises attached. Some crabs use aquatic mosses and sponges to disappear among rocks, while others get a little craftier. A few species stick stinging anemones on their backs—a perfect combination of offense and defense—while others choose toxic algae and sponges. While some disguises are purely visual, others can also fool a predator’s sense of smell or taste.

A lacewing larva with some bright camouflage.
A lacewing larva with some bright camouflage. Judy Gallagher/CC BY 2.0

Decorator crabs aren’t the only species that use objects or plants in their environment as mobile camouflage. Xenophora snail shells are frequently adorned with smaller shells, rocks, and coral. Caddisfly larva make fancy, protective tubes of tiny rocks or snail shells. And lacewing larvae have bristles on their sides that pick up bits of foliage as they feed. But the prize for craftiest—and most morbid—goes to the assassin bug, which carries around the dried out corpses of its insect prey on its back. Sometimes, nature rewards the strange.