During the winter, most worms remain in their burrows, trapped beneath dirt that has frozen solid as rock and is capped by ice and snow. They are curled into slime-coated balls and enter a sleep-like state known as estivation, which is analogous to bear hibernation. (The mucous, or slime, keeps the worms moist.) Some species can move about within the soil during this time, but most stay put for safety's sake. When spring arrives and the weather warms up, they wake up from their nap and begin feeding on the organic matter in their surroundings.
Worms play an important role in ecosystems because they decompose plant material that would otherwise be available for other organisms to eat. In fact, they help break down manure and compost so that it can be used on garden plants. Worm farms are used to produce edible worms for food and as fertilizer for gardens and farms. People also use earthworms for scientific research studies.
There are several types of worms that respond differently to environmental conditions. For example, some species will escape freezing by forming a protective shell of silk proteins. This is called diapause and it allows them to survive until temperatures rise again. Others depend on internal body heat to keep warm instead. Still others find shelter in decaying vegetation or under rocks where it is cold but not completely frozen.
People have been farming earthworms for thousands of years and they are still popular today in parts of Europe, Asia, and North America.
Certain worms may thrive in a wintering environment. These worms will survive by burrowing deep into the dirt to keep warm from the ice. Worms and earthworms will still dig into the ground under normal conditions, but not deep enough. They will dig based on their exposure to sunlight. Long daylight hours and cold temperatures cause them to go deeper.
Other worms may freeze during the winter months and then thaw out once spring arrives. When this happens, they grow back together again like pieces of a puzzle. Most insects die off each year, too. Some species can be found frozen in ice caves during wintertime while others hide underground or in woodlands.
Some worms migrate to warmer climates for the winter. For example, the American leopard worm lives near the surface of the soil in temperate regions of the United States and Europe. In the winter, it moves down below the frost line where it digs itself holes to protect itself from the cold.
Worms are an important part of our ecosystem because they are eaten by other animals. For example, cattle feed on the roots of grass plants, which is why farmers cut the tops off of their fields before harvesting it for meat. Certain worms help cows digest their food more efficiently which means less gas for humans to smell!
In conclusion, worms play an important role in maintaining healthy ecosystems because they recycle nutrients and move energy around the soil.
Worms must dig below the frost line wherever they inhabit in order to survive in subzero conditions. Night crawlers, for example, have the ability to dig to depths of six feet or more. They nest in little chambers at the bottom of the tunnels they make when they burrow below the frost line. Dayworms only need to get underground during the warm summer months and don't worry about freezing even if you live in a cold climate.
The length of time that worms can stay frozen depends on the species and how deeply buried it is. For example, a worm that's only covered by an inch of soil can stay frozen for several years until spring thaws out its habitat. A human body will usually be buried deeper than an inch, so it would not be able to survive such cold temperatures.
The point at which worms stop moving is called their "freezing point". If they're exposed to temperatures below this point, they'll start to freeze instantly, which could cause injury or death. However, if they're protected by soil or some other material that keeps them warmer than the surrounding ground, then they can stay alive in extremely low temperatures.
In the wintertime, the temperature inside a worm's tunnel may fall below freezing while the ground outside is still being warmed by sunlight. Since nightcrawlers can't see, they rely on sensitive nerve endings called "cephalic glands" to find food and water.