Eels belong to wetland ecosystems.

In natural waters, eels hide in the dark during the day and come out at night to feed. It mainly feeds on small fishes, crabs, shrimps, crustaceans and aquatic insects, and also eats some rotten carcasses of animals and scraps of higher plants. Eels kept in ponds also like to feed and live in shaded places. Eels are phototropic to low light, and as the eel grows, this phototropism weakens or disappears.

Breeding habits of eels

The gonads of eels cannot develop well in freshwater and can only stay at an early stage. In February and April, eels with a body length of up to 45 centimeters or less are often difficult to distinguish between the sperm and the ovaries. Eels with mature gonads come down from the river in the fall and winter, and mature only after entering the sea, and their body color becomes blue-black, with a layer of golden luster on the side of the body, and the base of the pectoral fins becomes golden yellow, presenting the so-called "marriage color".

The sexually mature female and male eels arrive at the spawning ground in pairs, where they spawn and reproduce. But after the parent eels spawn, they are exhausted until they die.