Yellow eel and Silver eel

Elvers continue to grow larger and become the “eels” we are familiar with

The back of an eel has a greenish bronze-like color, and the belly is white but slightly yellow.

This stage is called “yellow eel,” perhaps because the band-like yellow color between the back and belly of the eels might have been impressive to the person who named it.

(However, eels at this stage exhibit many color variations.)

This yellow eel stage, eels are consumed for food, such as Kabayaki.

Yellow eels, those have grown for 5–10 years, metamorphose again when they reach sexual maturity.

(This change is not as dramatic as the one from the larva to glass eel.)

Their eyes and fins became bigger to enable them to swim 2,000 km to the spawning area, and the color of their body also changes.

Because their skin changes to a metallic color at this time, they are called "silver eels” and this metamorphosis is called “silvering.”

After metamorphosing into S1 stage with the beginning of sexual maturity, eels turn into S2 stage while they swim toward the spawning ground.

Without sleeping or eating, eels swim toward the spawning area, the place where they were born, and end their life after breeding.