Salmon is a whitefish. The pink/red color of their (wild caught) flesh is due to their diet at sea. Specifically, shrimp eat algae which has a pigment that gives their shells and flesh a pinkish color and Salmon eat shrimp.
Sorry, this was just a joke at the expense of the op. The op who asked the question obviously didn't read the article as the fact that farmed salmon is dyed was literally the first line. The second is why it was pink in nature.
