Oh man… I’ve got a routine that I go through regarding color selection that starts before the sun sets and gradually progresses back through moon rise. Guys will often say that there’s a flurry at sunset and then again once the moon is high. Between that the bite gets tough. And they keep pulling the same plugs that boated fish when the sun was setting and will again produce once the moon throws its light on the water. The fish don’t stop feeding… they stop seeing your baits well. I’ve found a couple tricks to keep the bite running hard through those supposed slow periods and that red is one of them. On the flip side, try fishing that red with a full-high moon some time and let me know how worthless you think it is!…lol
But to answer the question of what does it imitate…. Nothing. But was does clown REALLY imitate w/ its chartreuse head and that dash of red?…lol Again, I think it’s a matter of visibility in water in when light levels are very low. To go a little further, with the absence of light, a walleye will better see a DARK contrasting crankbait than it will a naturally patterned one. With a little light to work with that natural pattern will again be the best producer.
For me, when the moon is blocked out and the night is SUPER dark… that dark red is tough to beat. You asked a very good question.