Do Worms Eat Other Worms?

Are you concerned about your composting worms having a nibble at each other?

Before starting your own worm composting bin or worm farm, you may be worrying about what will happen if they run out of the food they are craving.

Do worms eat worms or consume other worms after turning on each other?

In some cases, yes, worms will eat other worms. But don’t worry!

While worms chow down on decaying and dead matter, they are not predators and will therefore not intentionally attack another living creature, especially one of the same species as itself.

They will, however, eventually consume the decomposed body of another earthworm. 

Will worms eat dead worms? 

Yes, worms do eat dead worms. Gross but true – a dead worm is instant worm food for the living!

Generally, they thrive on the nutrients that are provided by the various plants, fruit and vegetable remains you feed your worms.

These could be apple cores, banana peels, any organic waste or organic matte, soil or bedding material that happen to be surrounding them during their short lifetime.

However, as it turns out, worms like to consume practically any naturally decaying thing.

The matter being released into the soil from other decomposing animals, including humans, will eventually be eaten by a worm.

However, they’re not zombies or cannibals – as they much prefer food waste and food scraps.

They do not immediately feed off of the flesh of a dead worm.

In fact, it will take quite a bit of time before the living feeder will be able to benefit off of the death of another worm.

The dead worm has to pass through the various stages of decomposition before become edible for other worms.

Does eating other worms impact worm castings?

Worm poop, or castings, will carry all kinds of nutrients – including from dead, eaten wigglers!

Just as with fruits, vegetables and plants, the nutrients provided by decomposed red wigglers will eventually pass through the various stages of digestion in the live worm, and will become worm castings, capable of nourishing the soil around it.

Worm castings are very beneficial for soil and the growth of any vegetation sourced by it, as it is filled with nutrients and enriches the soil in various ways. 

If you do happen to have a worm bin and are concerned about the dead worms within, don’t panic. A decomposing body will eventually enrich the soil.

However, remember to keep feeding your colony as much of a varied diet as you can.

A rich complex of manure and bedding will support balanced nutrients.

You can’t and won’t want to rely on your critters feeding off each other. It kind of defeats the point of your worm bin or farm if they eat each other!

They need a mix of different foods and scraps, as you may know already.


It’s possible for one worm to eat another, but only when they’re dead and decomposing. It won’t have a negative impact on your compost.

However, don’t avoid giving them other foods, obviously. A varied diet will make for nutrient rich compost.

Make sure to feed the worms a mixed variety of food and take care of them so you never have to find out if a worm can eat another!

Worms cannot eat another live worm and won’t start doing fighting it out in your worm bins (at least, the earthworm species won’t)

The biggest concern isn’t that the worms are feeding on other dead worms, it’s that the worms are dying in your bin or farm in the first place.

Do moisture, PH and other tests to make sure the environment is optimal in your bin.

Avoid feeding your worms certain foods and add things to balance others out. (Adding shredded paper to an overly moist bin, or spray water into a dry bin, for example)

If you would like to know more about what to get and use in vermicomposting, take a look at our other small guides on keeping worm bin systems.

For example, did you know that worms eat seaweed as well as fruit and food scraps?