Quirks and Quarks

Cuttlefish Hold Their Breath to Avoid Sharks

By stopping respiration the cuttlefish damps its bio-electrical field which helps it hide from sharks and other electro-sensitive predators.

Breath-holding hides from Sharks bio-electrical sense.

Common Cuttlefish (Jarek Tuszynski, cc-by-sa-3.0)
The cuttlefish is a type of mollusc that lives in many oceans around the world, and is common off the coast of Europe. Because it can change colour and even texture to evade predators, it is known as the Chameleon of the Sea.

But a new study by Dr. Christine Bedore, an Assistant Professor of Biology at Georgia Southern University, has found that cuttlefish have an additional strategy to hide from predators, including sharks.

By holding their breath, they stop generating the bioelectric field created by their respiratory system. With this so-called 'freezing' behaviour, the cuttlefish becomes invisible to the electro-reception used by sharks to find prey.

Related Links

- Paper in Royal Society Proceedings B
- Duke University release
- Science Magazine story
The Guardian story