Accommodating and Breeding Java Sparrows
The Java Sparrow must certainly be regarded as a large finch. The typical Java Rice Bird is five and a half inches in length (including the tail which is more than an inch long). They are heavy-bodied finches with exceptionally massive beaks, giving the bird a distinctive appearance. Even in silhouette, one could readily identify a Java Rice Bird. In my opinion, Javas have been falsely portrayed as aggressive birds. There is no doubt that the size of the bird and its large beak command respect from other birds. However, unlike many truly aggressive finches, the Java is not a bully, and does not seek to do harm to any aviary occupant. They can be quite docile towards even the smallest of finches. I believe their reputed aggressive nature originated from observations on their behavior that have been wrongfully interpreted. I certainly have kept them with a variety of exotic finches over the years and cannot say that they ever caused me to be concerned for the safety of the other finches. I always tell my customers that single pairs of Java are well suited to a mixed collection, but that too many Javas in an aviary are likely to dominate the other birds. This would be true for any finch. A single pair or small group of Java Sparrows, provided they have enough space, housed in an aviary containing a mixed collection of finches should not cause problems.
Java Rice Birds adapt more readily to aviary life than to cage life and can withstand a wide range of temperatures. Only in severely cold climates (prolonged temperatures below 25ºF) must they be moved into heated quarters. Javas also fare better in the company of other finches, especially other Javas, rather than as single pairs. They are highly social finches, and thrive in the company of each other. Their noticable constant bickering with each other is nothing to be concerned about. If they dont' behave this way, there is cause for concern! I breed all of my Javas in sizable colonies in spacious walk-in flights. My flights are 12 feet long, 4 feet wide and 7 feet tall. Often these colonies of Javas are adjacient to one another and I believe it only stimulates them more. Many of my colonies have 15 to 20 or more breeding pairs. Pairs can be quite productive, rivaling that of the Zebra and Society Finches. It is not unusual for first time breeding Java Sparrows to produce 6 and 7 young per nest, and to do this repeatedly! I also have individual pairs of Javas in a mixed colony of other finches and these also thrive and breed very well every season as is evident the the accumation of birds in the flight at the end of the breeding season. Javas can also be bred in individual cages, although in my experience they are often nervous and slow to nest in small cages. However, once acclimated to life in a smaller cage, they can be equally productive as they are in the aviary.
Javas prefer a large nest, somewhere between a standard finch nest and a parakeet nest box. They are less likely to choose a small box or wicker basket. Unlike so many other finches, their nest is quite untidy, and often poorly made. They place very little nesting material in boxes before settling down and laying a clutch of eggs. Javas prefer large, coarse nesting material such as rough hay, large grasses, and even long pine needles. Don't bother offering them soft, fine nesting material, such as you would Zebras or other exotics. The Java will always prefer coarse material. The nest is usually deep, cup shaped and often consist if little more than a small handful of nesting material. The average clutch is 5-6 eggs, often times as many as 7 and 8 are laid. Don't be surprised if all of them hatch, and if they all fledge. Javas are good parents!
Proper care for Java Sparrows requires only a modest effort on the part of the keeper. In the wild state, Javas eat a tremendous amount of rice. Oddly enough, I have offered rice to my captive Javas and they showed no interest in it. The diet of Java Rice Birds in captivity is very simple. They adapt very well to the same diet preferred by Budgies (parakeets). A standard parakeet mix containing large white proso millet, plain canary seed, and oat groats is the basic requirement. The canary and millet can be in given equal proportions, or the percent of canary seed can be somewhat lower. Oat groats are relished and should comprise about five to ten percent of the mix, perhaps more in breeding seasons and winter months. A standard finch mix is also quite suitable for Javas, although I think they would prefer the larger seeds found in parakeet mix. I routinely give my Javas a soft nesting food several times per week during the breeding season and on rare occasions I offer them greens. They love both! My Java always have access to an aromatic finch mineral grit which I buy from Sunshine Bird Co. in Miami, Florida, and finely crushed egg shells, which I get daily from a local Chinese resturant. I mix the two in equal proportions. They consume tremendous amounts grit and eggshell, especially during the breeding season.