Worms are, simply put, a very efficient digesting tube, made of 90-150 segments. There are about 200 different types of worms in New Zealand, with about 2,700 species internationally, who all live in different habitats.

Earthworker worms live deep in the soil, creating tunnels for air, water and plant roots, and bringing subsoils closer to the surface where they mix it with the topsoil. All worms live where there is food, moisture, air and a temperature suitable to the species. If conditions aren’t right, worms can travel up to 2kms in search of a better home.

Worms can grow a new tail, but not a new head! They have no arms, legs or eyes, but they are very sensitive to light through cells in their skin. If an earthworm is left in the light, it will become paralysed after about 1 hour.


Worms breathe through their skin, and will leave their tunnels when it rains hard because the burrows fill up with water and drown them. They have bristles around their bodies and special muscles to push them through the soil. They also excrete mucous, which not only stops the walls of the burrows (tunnels) from collapsing, but also serves to encapsulate the castings (or worm poos), making them into a slow release fertiliser.

Worms are hermaphrodites – containing both male and female organs. They mate by joining their clitella (or saddle, the swollen area near the head of a mature worm) and exchanging sperm. Each worm will then form an egg capsule in its clitellum, which can contain from 1 to 20 worms, depending on the species. The capsules, or cocoons, start out pale yellow and turn to reddish brown when they are nearly ready to hatch. An adult worm can produce an egg capsule every 7-10 days, taking 21 days to hatch, with the worms becoming reproductively active from 60 to 90 days old onwards. Research doesn’t show how long worms can live for, - appears to be anywhere from 1 year to 10!

Did you know: It was a New Zealander who showed that the weight of earthworms found under pasture was similar to the weight of the animals grazing above the ground?

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