Among painters and graphic designers it's generally agreed that yellow in combination with black produces what for us is the ultimate in stand-out contrast. It makes sense that most warning signs use the combination. And consider how well the yellow dividing lines on blacktop roads work. Firing Up Fish Interior decorators and Web-site developers have keyed on research showing that yellow is the color we see most quickly in a group of colors. Psychologists who study such things have found that yellow has a decided stimulating effect on people.
Nothing is said about fish, however.
Yellow, then, is surely an attractor color. I think that in dark water yellow stands out better, like those cautionary signs with black and yellow. Look at what happens to the color as it goes deeper. At around 20 feet, red turns brownish-black and orange goes brown, while yellow is just beginning to fade. At 60 feet, red and orange are jet black and yellow turns white, perhaps suggesting a dead or dying forage fish fluttering down.