As the fish matures, the number of pigment cells increases until the fish becomes almost entirely black in adulthood.

These may fade as the fish matures.

This striping is prominent in juveniles and fades as the fish matures at about three or four years old.

During this time the fish grow and mature in large cages off the coasts of Canada, the United States, or parts of Europe.

However, as the fish matures, electrogenic organs derived from central spinal cord gradually replace the muscle cell-derived electric cells.

Juveniles show around 5 vertical bands, which fade to blotches and finally disappear altogether as the fish matures.

When the fish matures, a prominent orange drop shape develops on the caudal area, terminating into a sharp spine.

Juveniles have a black lateral line that extends from the beginning of the eye to the caudal fin that fades as the fish matures.

Finnage may take a reddish hue as the fish matures.

As the fish matures, the spots fade.