Both the females and males will get darker. Has nothing to do with the sex of the fish. Has everything to do with how much sunlight is hitting the fish. They will get dark just like people tan. The males are up shallow now preparing beds for the spawn. They are getting more sunlight due to bein shallow, so they get darker. When the females move shallow to spawn they will get dark too. It is like the fishes skin is getting a tan.
In muddy water they will be pale and clear water they will be darker