Interesting link.
http://www.nytimes.com/video/science/100000002638616/sciencetake-fluorescing-fish.html
The link above is about the recent discovery of large numbers of salt water fish that fluoresce when exposed to blue light. Bioluminescence is different. Bioluminescence involves chemical reactions that
produce light--where the light in question originates inside animal tissues. Fluoresence happens when incoming blue purple or ultra-violet light is modified so it
reflects back as part of the (humanly) visible spectrum. Usually as glowing yellow red or green. Blue purple and violet radiation is interesting for a variety of reasons including its narrower wave lengths, which allows it to penetrate to the deepest levels.
As depth increases (sometimes only a few feet, depending on sediments clarity and other issues) the blue part of the spectrum predominates. To the extent other parts of the spectrum appear at all they tend to appear as muted shades of gray. In other words, at sufficient depth, most colors fade to gray and then disappear into black. However, it now seems fluorescent reds yellows and greens
also appear at depth, at least when blues are modified by certain fishy tissues.
In the fresh water context earth worms are known to fluoresce. I wonder what else. Has anyone ever gone scuba diving, in fresh water, armed with a black light and video camera?