Gold Bass? It’s true, but is an extremely rare occurrence that is believed to be caused by a genetic mutation. This genetic anomaly is known as xanthism. It can also affect birds, reptiles and other species of fish. This mutation causes the fish to lose its ability to produce the colors needed to turn its scales green. Fish that have survived to the ages in the photos below appear healthy in nature. Although some of the photos floating around the internet are photoshopped this myth can be confirmed as TRUE.