Jim I learned this quite by accident. I always carry at least one 5 gallon bucket around the pond with me in the back of my UTV. Some times two. I had always just grabbed whatever bucket was handy, not paying any attention to the color. I use the bucket to transfer fish, temporarily hold them till I get them to the holding pen for filleting, etc.
I started noticing when I had a black bucket the fish color was much darker when I pulled them out of a black bucket. I also noticed the fish were less jumpy and less likely to jump out if I had the bucket a little too full with the black bucket. With a yellow bucket I had, every time I moved around the bucket, the fish were agitated. Not so with the black bucket.
I should have known this. I spend around 200 hours under water every year observing ocean fish (just completed 100th dive for this winter trip 2 days ago, do about 200 a year). I see certain varieties of salt water fish be able to change their colors instantly to match their mood or background. I knew fresh water fish had some capability to change colors. I just did not know it was as pronounced as it is until accidentally discovering it.
