Java Sparrows are large, full-bodied finches. Measuring over 5-1/2"
have impressive beaks that look like they could do some serious damage,
however, they are harmless. Males and females are nearly identical in
appearance. There are a number of ways to distinguish between the sexes.
Like most members of the Lonchura family, the males sing and perform a
little dance. The dance is not much to see and many don't think much
about the song, but I find it a pleasant, tropical sounding song. Unlike
most mannikins, you can actually hear it for some distance. Waiting for
them to sing can be a test of patience however.
A better way to sex Javas is with a couple of visual clues. These
differences are better seen in a large group of birds rather than
looking at one pair. On a male in breeding condition, the culmen (the
top of the beak, especially where it meets the head) has an apparent
swelling. A definite ridge will form and the color will turn a deeper
red on the males. It is said that the eye ring turns a richer red as
well, but I find the beak easier to see.
Despite their large size and formidable beak, Javas are peaceful
birds. They will get along well with smaller finches in a mixed aviary
setting. The ones they will bicker with are themselves. Get a group of
them together and there will be a lot of bill fencing and squabbling
noises, but they rarely do this with other finches. I have never kept
them with the smallest of waxbills, but I don't think they would cause
them any harm either. I also kept them with the little Rufous-Back
Mannikin and that pugnacious little bird held his own against the Javas.
The Java Sparrows diet begins with a basic parakeet seed mix. You can
use a standard finch mix, but these often contain a number
of smaller millets that the Javas will ignore until the last large white
millet is gone. You can also offer them just plain White Prosso and any
other seeds in a separate dish. Javas will often seek out the oats in a
Parakeet mix and will sift through the seed until they find it all. In a
gravity feeder, this means they will drain the entire supply and scatter
the seed looking for the oats. It is best to offer them and they will
eagerly take egg food (Roy's egg food mix), gamebird crumbles and green
food. I have never seen them eat live food, but suppose they could be
enticed to if you really insist (but why feed livefood if you don't have
to). Calcium can be provided in the form of crushed egg shell, crushed
oyster shells or cuttlebone, but they are not normally enthusiastic
about the cuttlebone. Despite their name, they really don't eat a lot of
Rice. I have offered them Paddy Rice like I do all my Mannikins and
Munia, but they are not as enthusiastic about this seed as some of the
other Lonchura. They do like the Paddy Rice in a sprouted form.