© Martin Cooper


1 Hidden commoner

Turn over any log, rock, piece of wood or other debris and you are likely to find common rough woodlice. The species is found across the UK in almost any habitat except some cold highland areas. They are flat, oval and uniform grey with a thick, bumpy exoskeleton and have seven body segments, each with a pair of legs.

2 Ocean origins

Though they look like millipedes, woodlice are actually crustaceans, related to shrimps and crabs. This makes woodlice some of the few truly land-living crustaceans (most have to return to the water to breed). Like their aquatic relatives they do not have a waxy body covering so they easily dry out. This is why woodlice hide away in cool, damp places during the day and come out at night.

3 Around the globe

The common rough woodlouse is one of the toughest of the UK woodlouse species, tolerating dry and salty conditions, such as coastlines. Thanks to their toughness they have survived being accidentally transported across the world by humans. Common rough woodlice now live on every continent except Antarctica, including some isolated islands like Hawaii.

4 Nature’s recyclers

As well as decaying wood, common rough woodlice feed on leaf litter, fungi, fallen fruit, dead animals and even faeces. They even eat their own excrement, an act known as coprophagy. The species does this to recycle copper in their diet as their blood is copper-based like marine crustaceans. Woodlice also play a vital role as decomposers - compost heaps are woodlouse heaven!

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5 Stinky pigs

Woodlice make a distinctive bad smell by excreting ammonia through their exoskeleton. As a result, many local names for woodlice liken them to pigs, such as ‘chiggy pig’ (Devon), ‘gramersow’ (Cornwall), ‘sow bug’ and ‘woodpig’. You can test this by keeping woodlice in a jar for a short time and sniffing the air inside.

6 Protective mothers

Female woodlice have a ‘brood pouch’ similar to kangaroos. The mother lays her eggs into the pouch and her offspring hatch inside. Even when they have left the pouch, the mother stays close to her young for a few months until they mature. Common rough woodlice usually live for two to three years.


Buglife is the only organisation in Europe devoted to the conservation of all invertebrates. The trust is actively working to save Britain’s rarest little animals, everything from bees to beetles, worms to woodlice and jumping spiders to jellyfish.