rgbmatt
Contributor
rgbmatt; right now we just refer to the pale one as the older one because it is the larger one. We of course speculate that the more colorful one is male, but how would we really find out while leaving them relatively undisturbed in the wild.
The only sure way to tell would be to catch both eels and dissect them, which I'm sure nobody wants to do! I've seen pale and colorful dragons of all sizes, so it doesn't seem like it's an age thing.