My refernces disagree with you on this point. I do not know the correlation between the colorful fish and colorblindness. Not all fish are reef-colored and this may be an important correlation. The color in lures that fishermen use is mostly for the fishermen. The fish they catch usually only see the variations.
Aquatic mammals tend to have better vision.
Both livestock and fish are awfully large groups, I was reluctant to state it that way initially. I believe that cattle are also strictly black-white colorblind. Anyway, I've never been particularly interested in livestock, so I can only repeat what I've been told or have read - and remember. However, as usualy, I've been out of college for two decades. I've noticed a few changes since then.