What are the characteristics of earthworms' living habits?

Earthworms prefer warmth, moisture, darkness and quiet, and are afraid of light, salt and pungency; they are also plant-eating and burrow-dwelling. Earthworms generally reach sexual maturity at 4 to 6 months of age, and can mate once sexually mature, usually at night. During mating, two earthworms position themselves head-to-tail, with their ventral surfaces pressed together, and each deposits sperm into the other's spermatheca, while eggs are released from the female pore and combine with the foreign sperm in the spermatheca. The fertilized eggs are deposited into the cocoon to hatch, and the hatching time depends on the species and temperature, ranging from more than 10 days to over a month. They can lay eggs 3 to 4 times a year, and the suitable breeding temperature is 15 to 27°C; March to July and September to November each year are the peak breeding seasons for earthworms.

Preference for warmth

Earthworms like to live in warm environments, and their body temperature changes with the external environmental temperature, making them poikilothermic animals. Therefore, earthworms are markedly dependent on their environment: environmental temperature not only directly affects their body temperature and activity, but also affects their metabolism, growth, development and reproduction; moreover, temperature strongly affects other living conditions, thereby indirectly affecting earthworm growth. The survival temperature for earthworms is 0 to 40°C, among which they become dormant at 0 to 5°C, the suitable growth temperature range is between 8 and 30°C, the most suitable temperature for growth and reproduction is 15 to 27°C, and growth stops above 32°C. There are certain differences depending on the species.

Preference for moisture

Earthworms like to live in moist soil. Because they have no specialized respiratory organs, oxygen in the air must first dissolve in the water on the body surface and then enter the capillaries of the body wall through diffusion; the carbon dioxide produced by respiration is released into the air through the reverse process, so the body must remain moist to breathe normally. If an earthworm's body dries out, it quickly suffocates and dies because it cannot breathe normally. However, excessively high humidity is also harmful to earthworm respiration, and earthworms in soil soaked or flooded by water often escape. The humidity range of the earthworm's living environment is 10% to 70%, and the suitable humidity is 60% to 70%. Different species have certain differences in humidity requirements.

Burrow-dwelling nature

Earthworms live underground throughout their lives, generally inhabiting soil at a depth of 10 to 20 cm. They like moist, loose soil rich in humus, especially fertile courtyards, vegetable gardens, and places such as garbage heaps and under stones near pigsties and cowsheds in rural areas. The soil must have good aeration, which on the one hand can promote earthworm metabolism and on the other hand makes it less likely to produce harmful gases such as hydrogen sulfide and methane. Earthworms are very sensitive to soil acidity and alkalinity; they cannot survive in strongly acidic or strongly alkaline environments, and the suitable soil pH range is 6 to 8.

Aversion to light

Earthworms are nocturnal animals and are very sensitive to light; they prefer darkness and fear strong light. Under normal conditions they lie still in their burrows during the day, and at night they carry out activities such as digging, feeding and mating. In artificial breeding, a shed should be built above the breeding pond to shade the light and prevent direct sunlight.

Plant-eating nature

Under natural conditions, earthworms are mainly omnivorous animals with a predominantly plant-based diet, and like to swallow decaying fallen leaves, dry grass, vegetable scraps, crop straw, poultry and livestock manure, melon and fruit peels, food factory waste residue and household garbage. They are especially fond of sweet foods, such as rotting fruit, and also like foods with a sour taste, but do not like foods with a bitter taste or a tannin odor. In the soil, earthworms inhabit vertical layers, eating with their heads down, while their feces are deposited on the surface. The influence of food on earthworms is shown not only in the quantity of food but also in its quality. Earthworms fed on livestock manure grow faster, and the number of cocoons they produce is several times to more than 10 times greater than that of earthworms of the same species fed on plant-based feed, indicating that using decaying or fermented organic feed from animals to breed earthworms is more effective than plant-based organic feed.

Living environment and natural enemies

Earthworms like a quiet environment and are afraid of noise and vibration. The natural enemies of earthworms include 2 major categories: predatory natural enemies and parasitic natural enemies. Among the predatory natural enemies are various mammals, birds, reptiles, amphibians, arthropods, annelids, etc.; among the parasitic natural enemies are various tapeworms, nematodes, parasitic flies, mites, etc. In earthworm breeding, a quiet living environment should be created for them to prevent harm from natural enemies.