Imgur user AtheistChristianSockPuppet posted a clip of a little lovebird getting herself all gussied up by inserting strips of paper into her tail feathers. It's a ritual similar to the one so many human ladies go through before a special date. How do they know she's female? Easy, they asked her. Duh.
Ok, actually, according to that know-it-all science, she's not actually trying to be fancy. She's just gathering nesting material, and this is the easiest way for her to transport a whole bunch at once. Smart! And they know she's female, because this is a female-specific behavior, because males are lazy bastards. Typical. Still, a little colored construction paper thrown in might be a great idea if you want to give your nest a fresh spring look.