I know this is a well discussed topic but Ive been bored studying for finals and wanted to see what people thought.
After doing a little research I have found out that contrary to popular belief fish have eyes that are very similar to our own. They have both rods and cones and see the entire 7 color spectrum just as humans do as well as some being able to see uv light. Now I don't want to start a huge debate over the effectiveness of camo wetsuits but it would seem to me that at least from a visual standpoint they would have some effect. The argument to this is that fish have lateral lines and can feel the vibrations of other objects in their environment and this can sense the presence of a diver. In my experience when holding onto the bottom and staying as still as possible fish are not only less timid but often surprisingly curious. In some cases coming within inches of my face to investigate. In other cases, especially with grouper, I have seen fish dart under an overhang and then stare out at me and watch my every move. The conclusion that I have come to is that although fish may be able to sense objects movements and vibrations at a distance they not only trust but are more dependent on their eyesight. humans have very similar reaction and famously "must see to believe". Also if fish were able to sense things using there lateral lines that well than they wouldn't have developed their own forms of camouflage. Accordingly I feel like there must be some justification for the use of camouflage by spearos. Also, based on personal experience it would seem that fish are more intimidated by our size and position in the water column than by our presence. Hence if you act like a predator they react like your a predator. In this thread Im hoping to discuss hunting/stalking techniques as well as ways to reduce/hide your "signature" from fish.
sources: http://www.marinebiology.org/fish.htm
http://ambergriscaye.com/reefbriefs/briefs24.html
Personal experience
Thanks hope this turns up some interesting discussion.