Actually the darker the color, black or brown for instance, the more it attracts female mosquitos after blood. Only the females bite ...and that is just during their reproductive cycle, for extra protein to nourish the young (eggs) they're producing. The rest of the time she eats nectar (from flowers). Male mosquitos eat only nectar, but since they are both nectar eaters, it may be they are attracted to bright colors, however, not in their conquest for blood.