How Much Soil Can an Earthworm Eat?

An earthworm eats about one third of its own weight every day.

Earthworms or nightcrawlers eats varying amounts of soil from day to day. But, on average, an earthworm eats about one third of its body weight in soil every day.

Variations

There are more than 1,800 species of earthworms, with the largest species growing about 3 feet long according to the University of Florida. But the average weight of an earthworm is 0.39 oz. One third of that is 0.13 oz., which would be what that worm would eat in a day.

Function

Earthworms eat soil because their food is located inside of it. They eat microscopic bacteria from decaying plants, fungi, and microscopic roundworms called nematodes. It is easier for the worm to swallow dirt than to try and swallow each individual organism.

Significance

Digestable food makes up only a small part of every earthworm's mouthful of soil. They are not able to filter out their food from the soil. They need to eat so much soil to get enough real food. The combination creates droppings, called castings, that make excellent fertilizer.

References

• Biology Junction: Earthworm Facts: What do earthworms eat and how much do they eat in one day?
• National Geographic: Common Earthworm (Lumbus terrestris)
• University of Florida: Earthworm Biology

Resources

• BBC: Wildlife Finder: Earthworms
• Louisana Department of Environmental Quality: Did You Know ... Earthworms