Animal
Common earthworm
The common earthworm lives under the ground. It has no eyes, no ears and no legs. At night it comes up to pull leaves into its home.
The common earthworm digs deep tunnels in the soil and comes up at night to drag fallen leaves down to eat. It breathes through its damp skin, has red blood and five pairs of heart-like pumps. Its tunnels and droppings help keep soil healthy.
Lumbricus terrestris, the lob worm or nightcrawler, is a deep-burrowing (anecic) earthworm native to Europe and now common in North America. It mixes leaf litter into the soil from permanent vertical burrows. That can help compacted farm and city soils, but it changes hardwood forests in places such as Minnesota, which had no earthworms for about 11,000 years.
Photo: Donald Hobern from Copenhagen, Denmark, CC BY 2.0, via Wikimedia Commons
Meet the common earthworm
The common earthworm is a long, soft, pinkish-red worm.
It lives in the ground under gardens, fields and parks. It has no legs, but it can wriggle and dig.
The common earthworm is the big reddish-gray worm that many people know from gardens and fishing. In Britain it is called the lob worm, and in the United States it is often called the nightcrawler.
It is the largest earthworm in the British Isles. Most are only a few inches long, but some grow to about 35 to 40 centimeters. Its body is a long chain of rings called segments, and it has no legs, eyes or ears.
Lumbricus terrestris is an annelid, a segmented worm, in the family Lumbricidae. Of the 31 native or naturalized earthworm species in the British Isles it is the largest, reaching about 40 centimeters, and the Earthworm Society of Britain describes it as probably the most studied earthworm there and possibly in the world.
National Geographic gives a maximum length of 14 inches (about 35 centimeters) and weight of 0.39 ounces (about 11 grams), though most individuals are a few inches long. One exceptional British worm, nicknamed Dave, measured 15.75 inches (40 centimeters).
Quick facts
- Group
- Invertebrate
- Length
- up to 35 cm
- Weight
- up to 11 g
- Lifespan in the wild
- up to 6 years
Where it lives
Common earthworms live in damp soil.
They first lived in Europe. Now they live in North America too. People carried them there in soil and as fishing bait.
The common earthworm is native to Europe. People later carried it to North America, where it is now common, and it is abundant in western Asia too.
It lives in fields, gardens, lawns and woods, in a burrow that can go down about 2 meters. In Minnesota, scientists think the first earthworms arrived with soil and plants brought by ships from Europe. Today fishing bait spreads them to new places.
National Geographic describes L. terrestris as indigenous to Europe and now abundant in North America and western Asia. The Minnesota Department of Natural Resources explains that glaciers left the region without earthworms for the last 11,000 years; European species probably arrived in ship ballast soil and with imported plants in the late 1800s and early 1900s, and the use of night crawlers as bait has carried them farther.
Without people, earthworms spread slowly: less than half a mile in 100 years, according to the DNR. The map shows Europe as the native range and North America, where it was introduced, separately.
Continents
Its habitat
Where can you find this animal?
- Brought here by people · Countries and seas named by a scientific source
- Lives here naturally · Countries and seas named by a scientific source
- Sightings recorded · Records of wild sightings (GBIF)
Brought here by people · Countries and seas named by a scientific source
Brought to North America by people, probably first in soil and plants from Europe, and spread farther as fishing bait. The whole continent is shaded; the source does not list countries.
Places: North America.
Source: https://www.dnr.state.mn.us/invasives/terrestrialanimals/earthworms/index.html · checked October 2026
Lives here naturally · Countries and seas named by a scientific source
Native to Europe, in damp soils of fields, gardens and woods. The map shades the whole continent; the source does not list countries.
Places: Europe.
Source: https://www.nationalgeographic.com/animals/invertebrates/facts/common-earthworm · checked October 2026
Sightings recorded · Records of wild sightings (GBIF)
Counts of GBIF records of wild observations (human and machine) and preserved specimens. Records include introduced populations, vagrants, escaped or released animals and misidentifications, so a country with records is not necessarily part of the native range.
Wild sightings have been recorded in United States, Germany, UK, Canada, France, Sweden, Russia, Netherlands and 38 more places.
Source: gbif · checked October 2026
Range maps show where scientists say an animal lives, often country by country. An animal may live in only part of a country shown, and sightings records can include animals that wandered far from home.
What it eats
Earthworms eat soil and old, dead leaves.
At night they pull leaves down into their tunnels. Their droppings help plants grow.
Earthworms eat soil as they burrow, taking the goodness out of rotting leaves and roots in it. The common earthworm also comes up at night to collect dead leaves and pulls them down into its burrow to eat later. It can eat up to a third of its own body weight in a day.
Its droppings, called casts, are left on the surface. This brings minerals up from deep down, and the tunnels let air into the soil. Because it mixes deep soil and surface leaves this way, the Earthworm Society of Britain calls it nature's plough.
As an anecic species, L. terrestris combines nutrient-poor deep soil with surface leaf litter. In its gut these are mixed with enzymes and bacteria and released as casts at the surface, earning it the name 'nature's plough'. National Geographic reports that an earthworm can consume up to a third of its body weight in a day.
The effect depends on the place. In farm and city soils, burrows help water soak in and mix organic matter into mineral soil. In Minnesota's hardwood forests, which developed without earthworms, the DNR reports that invading worms can eat away the spongy leaf layer called duff, and many tree seedlings, wildflowers and ferns are lost.
A body made of rings
An earthworm's body is made of lots of rings.
Tiny bristles help it grip and move. It has no lungs. It breathes through its wet skin.
An earthworm's body is made of many ring-shaped segments. Each one has tiny bristles called setae, which grip the soil as the worm moves and burrows. Its mouth is in the very first segment.
Earthworms have no lungs. They breathe through a thin layer of moisture on their skin, so they must stay damp. They have no eyes or ears, but they can sense light and vibrations. Like you, they have red blood, pumped by five pairs of simple heart-like organs.
The body is divided into ring-like segments (annuli) bearing setae, bristles used in locomotion and burrowing; the mouth opens in the first segment. Adults have a clitellum, the swollen 'saddle' about a third of the way along the body.
Gas exchange happens across the moist skin, as there are no lungs, so the worm depends on damp surroundings. It has no eyes or ears but detects light and vibration. Unusually for an invertebrate, its blood contains hemoglobin and is red; a simple circulatory system is driven by five pairs of 'pseudohearts'. Mucus lines the burrow, letting the worm slide quickly up and down.
Growing up
Two earthworms meet at night to make eggs.
The eggs go into a tiny case shaped like a lemon. A few weeks later, a baby worm wriggles out.
Every common earthworm is both male and female, but it still needs a partner to have young. Two worms mate on the surface at night.
Afterward, each worm uses its clitellum, the fat band near the front, to make a tiny lemon-shaped case called a cocoon. It usually holds just one fertilized egg. The cocoon is buried, and two to four weeks later a young worm hatches. It is grown up after about a year and can live up to about 6 years.
L. terrestris is a simultaneous hermaphrodite: each worm has male and female organs and plays both roles when mating, but it does not fertilize itself. Mating takes place on the surface.
The clitellum secretes the material for a small, lemon-shaped cocoon, which in this species usually contains a single fertilized egg. The cocoon is buried, and the young worm emerges after a two- to four-week development period. Sexual maturity comes at around one year, marked by the clitellum. National Geographic gives a life span of up to six years in the wild.
A night crawler
In the day, the earthworm stays deep in its tunnel.
At night it comes up. If a bird comes near, it zooms back down. It piles leaves and stones over its door.
Common earthworms stay underground in the day, out of the drying sun and away from hungry animals. At night they come up to find food and to mate, which is how they got the name nightcrawler.
Their burrows go straight down and are permanent homes. If danger comes, the worm shoots back down. It also piles leaves, twigs and small stones over the entrance, called a midden. Long ago, Charles Darwin found that if he took a midden away, the worm rebuilt it the next evening.
The species is nocturnal at the surface, emerging to mate and gather leaves, and retreating by day to avoid drying out and predators. Its permanent vertical burrows, lined with mucus, allow a rapid escape, its main defense against birds and other surface predators such as rats and toads.
Each burrow entrance is capped with a midden of leaves, twigs, small stones and casts, thought to protect the opening from weather and drying. Charles Darwin, who studied earthworms closely, found that worms rebuilt removed middens the following evening. The invasive New Zealand flatworm is a threat in the British Isles because it can follow the worm into its burrow.
Did you know?
An earthworm has red blood, just like you.
Unlike most animals without backbones, earthworms have red blood, because it contains hemoglobin, the same substance that makes your blood red.
Hemoglobin in the blood of L. terrestris makes it red, which is unusual among invertebrates.
Earthworms and people
There are lots of common earthworms.
Some people think a worm cut in half becomes two worms. That is not true. Be gentle with worms you find.
The common earthworm is not endangered. The IUCN Red List has no assessment for it, and National Geographic describes its numbers as strong across its range. People use it for composting and as fishing bait.
A common mistaken idea is that a worm cut in half grows into two worms. The lob worm is very poor at regrowing lost parts, so usually only the head end might survive. Pesticides and plowing can harm earthworms. In Minnesota, people are asked not to dump leftover bait worms in the woods.
No IUCN Red List assessment exists for L. terrestris, and National Geographic lists no special status; in some areas it is even considered an agricultural pest. The Earthworm Society of Britain names pesticides, which accumulate in earthworms, and intensive farming, as plowing destroys burrows, as threats, along with the invasive New Zealand flatworm.
The species regenerates lost segments poorly, so the belief that a halved worm becomes two worms is unlikely to be true; a worm cut between the saddle and the head is unlikely to survive. Where it is introduced, as in Minnesota, the DNR asks people not to release bait worms, since there is no affordable way to remove earthworms from forests once they arrive.
Did you know?
Earthworms have no eyes, but they can feel light.
Earthworms have no eyes or ears, but they can still sense light and vibrations.
Lacking eyes and ears, L. terrestris nonetheless detects light and vibration, according to the Earthworm Society of Britain.
Amazing facts
-
An earthworm has red blood, just like you.
Unlike most animals without backbones, earthworms have red blood, because it contains hemoglobin, the same substance that makes your blood red.
Hemoglobin in the blood of L. terrestris makes it red, which is unusual among invertebrates.
-
An earthworm can eat lots of food in one day.
An earthworm can eat up to a third of its own body weight in a single day.
National Geographic reports daily intake of up to one third of body weight.
-
Earthworms put a little pile of leaves over their door.
Charles Darwin found that if he took away the pile of leaves and stones covering a worm's burrow, the worm rebuilt it the next evening.
Darwin's studies showed that lob worms rebuild removed middens the following evening, protecting the burrow entrance through the next day.
-
Earthworms have no eyes, but they can feel light.
Earthworms have no eyes or ears, but they can still sense light and vibrations.
Lacking eyes and ears, L. terrestris nonetheless detects light and vibration, according to the Earthworm Society of Britain.
Words to know
- segment
- one of the many rings that make up an earthworm's body
- setae
- tiny bristles on an earthworm that help it grip and move
- clitellum
- the thick band on a grown-up earthworm that makes its egg case
- cast
- an earthworm's dropping, left on top of the soil
- hermaphrodite
- an animal that is both male and female
- invasive
- brought to a new place where it spreads and causes harm
Discovery challenge
-
How does an earthworm breathe?
How does an earthworm breathe?
Through which surface does Lumbricus terrestris exchange gases?
- Through its damp skin
- Through lungs
- Through gills
Show the answer
Through its damp skin
It breathes through its wet skin, so it must stay damp.
Earthworms have no lungs; they breathe through a thin layer of moisture on their skin.
Across the moist body surface, which is why the worm needs damp surroundings.
-
When does the common earthworm come out of the ground?
When does the common earthworm usually come up to the surface?
When does Lumbricus terrestris usually forage and mate at the surface?
- At night
- At noon on sunny days
- Only in winter snow
Show the answer
At night
It comes out at night. That is why it is called a nightcrawler.
It surfaces at night to collect leaves and mate, which gave it the name nightcrawler.
At night; by day it stays below ground, avoiding drying out and predators.
-
What happens if a worm is cut in half?
What usually happens if a common earthworm is cut in half?
How well does Lumbricus terrestris regenerate after being cut in two?
- It becomes two worms
- At most the head end might survive
- It grows a second head
Show the answer
At most the head end might survive
It does not become two worms. Please be gentle with worms.
The lob worm is very poor at regrowing parts, so at most the head end might survive.
Its capacity to regrow lost segments is very poor; only the head end may survive, and a cut between saddle and head is unlikely to be survived.
-
Where did common earthworms first live?
Where is the common earthworm native?
Which continent is the native range of Lumbricus terrestris?
- Australia
- Europe
- Antarctica
Show the answer
Europe
They first lived in Europe. People took them to North America.
It is native to Europe and was carried by people to North America.
Europe; it is introduced in North America and abundant in western Asia.
Experiments to try
- Watch What If? Lab What if there were no decomposers? Bacteria, fungi, earthworms and millipedes break down dead leaves, wood and dead plants and animals, and give their nutrients back to the soil. National Geographic calls them Earth's cleanup crew. Imagine a world without them, and follow what might pile up, what might run short, and who does the work.
- Watch What If? Lab What if there were no soil? Soil is broken-down rock mixed with rotted plants and animals, plus water, air and huge numbers of living things. It holds plant roots, feeds them and soaks up rain, and UNEP says about 95 percent of our food comes from it. Under good conditions, one inch of topsoil can take hundreds of years to form. Imagine a world with no soil, and follow what might change.
Explore next
-
Watch
Animal
Garden snail
The garden snail is a land snail with a brown-banded shell about 3 centimeters wide. It glides on a muscular foot over a carpet of slime, comes out mostly at night and after rain, and eats almost any garden plant. It first lived in western Europe and around the Mediterranean, but people have carried it around the world.
-
Watch
3D
Animal
American robin
The American robin is a very familiar bird over most of North America, with a gray-brown back, a warm orange breast and a cheery song. It runs across lawns pulling up earthworms, eats lots of berries in winter, and builds a mud-lined nest for its sky-blue eggs.
- Watch What If? Lab What if there were no decomposers? Bacteria, fungi, earthworms and millipedes break down dead leaves, wood and dead plants and animals, and give their nutrients back to the soil. National Geographic calls them Earth's cleanup crew. Imagine a world without them, and follow what might pile up, what might run short, and who does the work.
- Watch What If? Lab What if there were no soil? Soil is broken-down rock mixed with rotted plants and animals, plus water, air and huge numbers of living things. It holds plant roots, feeds them and soaks up rain, and UNEP says about 95 percent of our food comes from it. Under good conditions, one inch of topsoil can take hundreds of years to form. Imagine a world with no soil, and follow what might change.
-
Watch
3D
Animal
Tardigrade
Tardigrades, or water bears, are tiny eight-legged animals about a millimeter long or less. They live in damp moss, soil, fresh water and the sea all over the world, and they can survive drying out completely by curling into a little barrel called a tun.
-
Watch
Animal
Pacific banana slug
The Pacific banana slug is one of the biggest slugs in the world, often as long as a banana and sometimes yellow like one. It lives in the damp rainforests along the Pacific coast of North America, where it eats fallen leaves, mushrooms and other plant matter, helping to recycle the forest.
-
Watch
Animal
American lobster
The American lobster is a big crustacean that lives on the rocky sea floor of the northwest Atlantic Ocean. It has two very different claws, one for crushing and one for tearing, and it must climb out of its hard shell again and again to grow.
-
Watch
3D
Animal
Antarctic krill
Antarctic krill are small, shrimp-like crustaceans about 6 centimeters long that live in the icy Southern Ocean around Antarctica. They gather in enormous swarms, and almost all the bigger animals of the Antarctic, from penguins to blue whales, depend on them for food.
For parents & teachers
What children will learn
- Describe how an earthworm's body works: segments, bristles, skin breathing and red blood.
- Explain how earthworms feed and how their burrows and casts change soil.
- Understand that an animal can be helpful in one place and harmful where it was introduced.
- Correct the mistaken idea that a worm cut in half becomes two worms.
Recommended ages: 3 to 17 · About 12 minutes
Talk about it
- Why do you think earthworms come out on damp nights rather than sunny days?
- How can the same worm be good for a vegetable garden but a problem in a northern forest?
- What could anglers do with leftover bait worms instead of tipping them out?
Try at home or in class
- After rain, look for worm casts and middens on a lawn or path, and count how many you find in one square meter.
- Make a simple worm-watching jar with layers of damp soil and sand and a few leaves on top for a day or two, then return the worms to where you found them.
Key vocabulary: segment, setae, clitellum, cast, hermaphrodite, invasive
Where these facts come from
- GBIF Backbone Taxonomy and GBIF Occurrence Search , Global Biodiversity Information Facility (CC0 1.0 (backbone); occurrence counts are facts derived from records under CC0, CC BY and CC BY-NC)
- Common earthworm , National Geographic
- The secret life of the Common Earthworm (guest blog by the Earthworm Society of Britain) , Buglife, The Invertebrate Conservation Trust
- Earthworms (invasive species) , Minnesota Department of Natural Resources
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Wikimedia Commons , Wikimedia Foundation (Per file: Public domain, CC0, CC BY or CC BY-SA only (credited on each page))
Checked, not yet human-reviewed. Last updated October 27, 2026. Spotted a mistake? Tell us.