The earthworm is known and recognized by most people. That familiarity can be linked to the fact that earthworms are found worldwide, with the only exceptions being deserts, polar regions and areas with very acidic soil.
Habitat
The habitat of the earthworm is moist soil, although some earthworms actually prefer mud, such as the mud that is found along the shores of lakes or swamps. Earthworms can be found in the soil of backyards as well as near bodies of fresh and salt water. Many earthworms live in the topsoil, while others dwell deeper in the soil. In tropical regions, earthworms may even be found in the soil that is found in tree branches.
Diet
The habitat of the earthworm is very important to their diet, as earthworms feed on decaying roots, decomposing leaves and plant materials that naturally occur in the soil. Depending on the species they may feed on plant materials deep in the soil or come up at night to feed on freshly dead or decaying leaves.
Benefits of Earthworms
Many people don’t realize it, but earthworms are beneficial to humans. Earthworms help to maintain the soil, as they naturally till the earth. The burrowing activities of worms help plants to grow by helping oxygen get into the soil and providing food to plants by mixing the soil with plant materials.
Species
Earthworms may not look like much, but not all are created equal. According to the World Conservation Union, there are seven different species of earthworms. The untrained eye may not be able to tell the difference between the species, but there are subtle differences in size, shape and body composition that distinguishes one species from another.
Vulnerabilities
While it might seem logical that the number of earthworms found in your garden suggests a thriving population, they are not immune to extinction. The Australian Lake Pedder earthworm is listed as extinct by the World Conservation Union. Phallodrilus macmasterae is listed as critically endangered, and three of four species found in the United States are considered vulnerable to extinction. The Gippsland giant worm is so rare that it has earned a protected status, meaning it cannot be caught or killed.