Abstract
The shaftail grassfinch iPoepbiia acuticauda) is a native of Australia, distributed along that country's northern coast from Derby in Western Australia ro the Leichardt River in Queensland. Although its entire range lies in the tropics, it inhabits dry savannahs, avoiding grassy plains and scrub areas, and is found most numerously near screams and waterholes.
In their native habitat shaftails prefer to breed in the highest branches of eucalyptus, sometimes constructing their nest inside a clump of mistletoe. Shaftails have also been found nesting in palms and even bushes and tussocks of grass in areas lacking tall trees. The nests are generally constructed of dried pieces of grass lined internally with plant wool, feathers and other soft materials. During the non-breeding season simpler roosting nests are constructed, which lack the soft linings.
Breeding season in the wild corresponds to the rainy season, when there is a prevalence of half-ripe grass seeds available ro feed the young. Consequently the breeding season may be very short or non-existent during dry spells and very extended during prolonged rainy seasons. Shaftails are capable of breeding any time of the year and commonly raise two to three broods annually.
The native diet of the shaftail consists primarily of ripe and half-ripe grass seeds. During breeding season this is augmented with assorted insects including flying ants and termites, which shaftails will hawk in mid-air.
The shaftail is one of three similar appearing finches; the other two are the related parson and masked grassfinches.
The shaftail has the crown and nape grey, mantle fawn, back and wings brown, band across rump and the tail feathers black, upper rail coverts white, and there is a vertical black stripe on each leg. The lores are black as is a throat patch, which is pear-shaped and larger in the male than in the female (otherwise sexes are alike). The breast and abdomen are pinkish fawn, the vent and under tail coverts are white, the legs and feet reddish orange and the eyes are brown. The bill varies from yellow to red. The parson and masked are similar in that the color patterns are identical from the breast down including the leg stripe. The parson, in fact looks like the immature shaftail in that both have a black beak, although the parson's crown and nape are darker grey than in the shaftail. The masked has a lemon yellow bill with a brown crown and nape. The masked' s bib is very small as opposed to the shafrail's and parson's.
It has long been believed by a number of breeders that two subspecies of the shaftail exist: the "shaftail" (yellow bill) and the "Heck's" (red bill). However, there is little evidence to support this taxonomically, since there is no other variation and no geographical boundary between the two "races." The westernmost population features the yellow bill and the easternmost the red bill, but there are all manner of variations in between. In captivity most birds feature a red or reddish orange beak, which is more attracnve.
Of all the finches cultivated in captivity perhaps none, other than the zebra, are more prolific than the shafrail. They may be colony bred, but are more productive when housed one pair to a flight.
Flights may vary in size from as small as a flight cage 4 ' x 2 ' x 2 ' to as large as the breeder can contemplate. Shaftails are not very discriminating in nest sites and will use boxes, baskets, plants, etc. so long as they have nesting materials sufficient in quality and quantity. Dried grasses, preferably devil or bermuda (which retain their strength when dry), along with feathers, clean dog hair, plant wool, etc. (for nest lining) amply satisfy that requirement.
Shaftails will lay 4-6 small white eggs, with one or two eggs often proving infertile. Incubation lasts approximately 14 days, sometimes a day less during warm weather. Newly hatched young are covered with natal down, which disappears as feathers develop. The young will fledge the nest at approximately 21 days of age and will continue to beg food from the parents for 10-14 days.