Under the Surface: 7 Earthworm Facts You Should Know

Updated: Aug. 10, 2023

Discover fascinating earthworm facts. These wiggly garden visitors are much more interesting and complex than you would expect!

Pink Earthworms In Garden Soil. Ground Cutaway With Worms. Farming And Agriculture. Hand Drawn Vector Illustration.malinikart/Alamy Stock Photo
You’ll be amazed by these earthworm facts.

Population Density

This one of our earthworm facts may surprise you. An acre of soil may be home to more than 1,000,000 earthworms when soil conditions are ideal.

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Earthworms Have a Big Appetite

Earthworms, which do have mouths but not teeth, may consume around half their body weight in a day.

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Friend or Foe?

Though it’s not uncommon to find earthworms in lawns or gardens, it’s best to not release any into these spaces or natural areas since they can disrupt local ecosystems. For instance, do not release excess fishing bait into the woods near your favorite lake.

How do American robins find worms?

Bnbbyc19 Ruperto MayugaCourtesy Ruperto Mayuga
A robin feeds its excited fledgling offspring with a juicy earthworm.

Earthworm Species

Researchers have discovered an estimated 7,000 species of earthworms around the world—but it’s likely that even more exist.

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Non-native Worms

Zero native earthworms live in certain parts of the northern U.S., and nonnative species pose a threat to some North American landscapes and forest ecosystems.

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Earthworm Lifespan

In certain cases, earthworms may live six to eight years (though fewer is likely).

After you finish reading about earthworm facts, check out surprising snail facts you should know.