Leech, commonly known as leech, grows and breeds in inland fresh water and lives in paddy fields, ditches, shallow sewage pits and ponds. Love to suck human blood and animal blood, very agile, can swim in waves and move inchworms. Warm spring is active every year, and the spawning period is from June to 10. In winter, I often crouch in the wet mud on the shore, and I have strong viability.

Life habit: Leech is a cold-blooded annelid, which can grow and breed in the north and south of China. Reservoirs, ditches, paddy fields and lakes that mainly live in fresh water are mostly ponds rich in organic matter or pollution-free rivers.

The optimum temperature for growth is 10-40℃, when it is lower than 3℃ in the north, it will enter a dormant period in the soil, and it will sting when it is higher than 8℃ in March-April of the following year.

Growth and reproduction:

Breeding habits Leech is hermaphrodite, hybridized, fertilized in vivo, and has two reproductive organs. Their mating direction is opposite, and there is a phenomenon of "gender reversal" in their life history, and there is a gender role exchange. Leeches can be both fathers and mothers, and play different roles in different stages of life.

About a month after mating, the female genitals secrete thin mucus, which is surrounded by the egg belt and is cocoon-shaped. It is excreted and incubated in wet mud at a suitable temperature. After about 16-25 days, the young leech hatched from the cocoon and began to live independently.