Purple Grenadiers-which were supposed to be so difficult to raise in captivity, particularly in cages-have turned out to be some of the most prolific breeders with which I have worked. They are by no means beginner finches but they are well worth the effort.
This beautiful, slender bird from the dry scrubland of central east Africa measures approximately five and one quarter inches in length including its long tail. The adult male is a reddish brown with a rich, glossy blue on the chest, belly and base of tail. A similar blue forms a rather wide eye-ring. His beak is a deep coral red. The female is a lighter brown, without the reddish tones. Her chest and belly are a mass of off-white spots which at times form irregular lines. Her eye-ring is most commonly a pale mauve or blue but can va1y from almost white to a blue almost as dark as in the male. According to Derek Goodwin in Estrildid Finches of the World, this variation in color could be an indication of different subspecies. The color is at least to some extent passed on: one of my females exhibited a much darker eye-ring than the others and, although none of her offspring have eye-rings as dark as hers, they are darker than average. The female's beak is a pale red. As she reaches full maturity and breeding readiness, a dark, almost black band appears down the length of the upper mandible.
Fledglings are entirely brown except for some purplish blue at the base of the tail. I have observed some slight differences in the shade of brown among my babies which, according to Derek Goodwin, indicates gender. I have not tried to confirm or deny this, however, since the sex of the youngster becomes obvious when at around six weeks of age a partial molt produces the colored eyering. At around four months of age a more complete molt results in the adult coloring though the male in particular displays a richer, more beautiful plumage after the second full molt. It seems as if both male and female display richer colors with each successive molt.
The newly hatched chicks are almost black in color, naked except for a few tiny tufts of down and have deep blue and white gape tubercles. They start out in life surprisingly small considering the size of the adults but they grow quickly and usually fledge at around two and a half weeks. I have, on occasion, been surprised to see them out of the nest as early as two weeks.
Although Grenadiers can sometimes be kept in community settings with no problems, I have, unfortunately, seen too many instances of incompatibility to recommend this as ideal. Grenadiers are aggressive toward related species such as Cordon Bleus and Violet-eared Waxbills. They can also take a sudden and violent dislike to non-related species with disastrous results--even after having lived peaceably with them for extended periods of time.
Grenadiers do not seem to be overly concerned about the size of cage or flight in which they are housed. However, since they are fairly large, active finches, they do need room to move around. My smallest cage for Grenadiers measures 36" x 22" x 22". I provide tumbleweeds and branches of Grevillea as hiding places, and, where there is insufficient natural lighting, I use full spectrum bulbs.
Like many other finches, Grenadiers are not as fragile as we sometimes think. Though they are obviously more comfortable when kept in warmer temperatures (70s & 80s °F.), they can endure occasional drops. Several of my pairs have been housed in an aviary where winter temperatures have quite regularly dropped...
GOODWIN D: Estrildid Finches of the World.
Cornell Univ Press. New York. 1982, pp 156-158.