The budgerigar, Melopsittacus undulatus, is a small Australian desert parrot which in the last century has staged a massive evolutionary coup by becoming one of the most popular cage birds in the world. Selective breeding has produced varieties that are bright yellow, white, blue or turquoise. Wild budgies are usually darkish green, with a yellow face and fine black banding over the head and neck and down the back and wings. Interestingly, much of the banding, as well as some small patches on the face, shine brightly under UV light.
Populations are still very healthy in the wild. Budgies avoid the coasts, living in the dryer inland regions, and flocks are found deep into the central deserts. They're hardy birds, able to tolerate huge extremes in temperature. They feed on plant seeds and whatever bonus greenery they can find, and get by on very little water. Although if they're in captivity, they love to take baths. They're intelligent, extremely social birds, travelling in huge flocks from waterhole to waterhole. These flocks, made up of thousands of birds, are a spectacular sight in central Australia, if one flies over your car you'll be in the dark for at least a minute.
They're also extremely loud. As anyone who owns or has met a budgie can confirm, they chatter almost continuously, a metallic burbling chirrup while perched, feeding, grooming, and even sometimes while sleeping. In the air, they have a louder version of this, a high pitched chattering, and an occassional two-note screech of a contact call. Which they do incessantly. Now imagine there's ten thousand of them, and on top of that they're all beating their wings at high speed. You get the picture.
They breed in hollows in trees, lined with feathers. Pairs tend to mate for life. In captivity, they should be given a nest box. Which is of course assuming you want more of them. Which you will. They're charming birds, my favourite parrot, they have a lot more individuality and character than the bigger, showier species. The only thing with more attitude and brain is a sulphur crested cockatoo. They're also an excellent aviary species, as a rule more than three pairs will get along fairly well, the more the better. Be warned, however: two or three pairs will fight like cats in a sack, for some reason. This tends to be the rule with most flock birds.
They also socialize very well with other species. We have a widowed female budgie who's taken up a rather worrying relationship with a female Rosy Bourke's Parrot, a pink, semi-nocturnal species about the same size as a budgie. They nest together and crop-feed each other. We're not entirely sure what's going on there...
And their name was provided by a desert Aboriginal language - it means "good to eat".