How Do Earthworms Survive the Winter? A Full Breakdown of Their Overwintering Methods
In winter, earthworms burrow deep into the non-freezing soil layers to hibernate and overwinter. That is where the temperature suits them. When the temperature drops below around 20 degrees, earthworms stop growing and begin hibernating. When it warms up the following spring, they become active again.
The living habits of earthworms
1. Nocturnal animals: Earthworms are nocturnal animals. They stay hidden in soil burrows during the day and come out at night to be active. They generally come out to activity from around 8 pm to around 4 am the next morning in summer and autumn. Feeding and mating both take place under dark conditions, and they prefer a quiet surrounding environment. Earthworms living around industrial and mining areas mostly grow poorly or escape. Although earthworms are distributed worldwide, they prefer relatively high temperatures. Below 8°C they stop growing and developing, and the most suitable temperature for reproduction is 22-26°C.
2. Omnivorous animals: Earthworms are omnivorous animals. Apart from glass, plastic and rubber, they will eat everything else, such as humus, animal feces, soil bacteria, fungi and the decomposition products of these substances. They have a keen sense of taste, like sweet and sour flavors, dislike bitter flavors, prefer warm, softened and fine feed, and are especially greedy for animal food. The amount they eat each month is equivalent to their own body weight, and about half of the food is excreted as feces after passing through the digestive tract. They have the habit of being unwilling to live together as two generations of mother and offspring, and especially under high-density conditions, when the young ones multiply too much, the old ones will run away and move.
3. Negative phototaxis: Earthworms are negatively phototactic, especially avoiding exposure to strong sunlight, blue light and ultraviolet rays, but they are not afraid of red light and tend toward weak light. This is why earthworms come out of their burrows on damp, overcast mornings. The toxic effect of sunlight on earthworms is mainly due to the ultraviolet rays contained in sunlight. Earthworms like a quiet environment, which not only requires low noise but also no vibration. Earthworm farms should not be built near bridges, highways or airports.
4. Cold-blooded animals: Earthworms are cold-blooded animals, and their body temperature changes with the temperature of the external environment. Therefore, earthworms generally depend more noticeably on their environment than warm-blooded animals. Environmental temperature not only affects the body temperature and activity of earthworms, but also affects their metabolism, growth and development, and reproduction. Temperature also has a major effect on other living conditions, thereby indirectly affecting earthworms. Therefore, temperature is one of the most important living conditions for earthworms.