This is a video of a group of dolphins swimming through bioluminescent plankton in Newport Beach, California and leaving trails behind them wherever the plankton is disturbed. Pretty trippy, right? It's like Avatar but in real life. Somebody call James Cameron, tell him I'm sorry for never seeing Avatar, but 3D glasses give me a headache. "You know you could have seen it in 2D." Dammit James I already said I was sorry, just drop it.
Keep going for the full video.
Thanks to DT and speakerbox, who agree this is probably where stories of mermaids came from. Plus, you know, actual mermaids.