almost all will partake of it some of the Waxbills time and the majority will eat it most of the time. Only the aberrant allies, the ant-peckers, negro-finches and olive­ and their Allies backs, with one exception, are truly Part 1 independent of any plant seeds (though the seeds found in fruit are consumed by Ian Hinze Whitefield, Manchester, England by some species), as these have devel­ oped specialized feeding habits more [Editor's Note: Ian Hinze has presented a be applied only to a small number of akin to insectivores and frugivores. The very long and complete treatise on the various African and one Arabian species and exception is the White-collared Olive­ waxbills and their allies, just as the title sug­ the two Asian avadavats, with "grass­ back Nesocharis ansorgei, which is gests. The work will be presented in a series of finch" being used to distinguish their believed to feed entirely on the seeds of several parts. Ed.l Australian cousins. Also, other English the composite Melanthera scandens. Introduction names came into usage to further dif­ Those waxbills that are heavily ferentiate species in the various gen­ dependent on grass for food also lead , 'WaxbillS" is a term era, such as "parrot-finch" for the lives inextricably linked to it in other used for small Erythrura and "mannikin" or "munia" ways. Besides the provision of seeds, finch-like birds for the Lonchura, etc. the grass yields up succulent young belonging to the family Estrildidae, In deciding on the title of this shoots and abounds with tiny insects. which is made up of around 128 dif­ series I was mindful of the fact that The grass also affords the waxbills pro­ ferent species in 27 genera (groups). there are a number of species the avi­ tection, as foraging for seeds that have These species range in size from being culturist would consider to be "good" fallen to the ground means they are a little smaller than a House Sparrow waxbills, in other words those of often at liberty to eat while, at the same Passer domesticus to being more which there is no doubt. These are all time, being camouflaged from many diminutive than the Goldcrest Regulus the typical Btrilda waxbills, which potential predators. Finally, its long regulus and they occur naturally only actually have "Waxbill" as their sub­ leaves and inflorescences are gratefully in Africa and eastwards through Arabia stantive name, as well as the firefinch­ accepted for use in nest construction. and India to southern China, south­ es, cordon-bleus, the Goldbreast and The grass family is one of the largest eastern Asia, Australasia and many of avadavats, twinspots, blue-bills, seed­ in the plant kingdom and contains the Pacific islands. To a scientist all crackers, crimson-wings and pytilias. about 10,000 different species. species in the Estrildidae are classed as But what of the quail-finches, Fundamental to the grass's growth is waxbills - but they are classed as estril­ negro-finches, olive-backs, and ant­ good light, it cannot survive in the did finches, too. To confuse matters, in peckers? And what, too, of the Cut­ deep shade of a forest. Some species aviculture, where it is agreed that all throat and the Red-headed Finch of waxbilllive and breed on the forest waxbills are estrildid finches, it is not whose closest relatives are believed to edge and so are able to quickly dart agreed that all estrildid finches are be the pytilias, so-called "good" wax­ into the bushes and trees at the first waxbills! This begs the question bills? And there may even be an argu­ sign of danger. For sustenance, how­ "What, then, is a waxbi1l?" ment for including the Australian Red­ ever, like their cousins who prefer or The name "Waxbill" was originally browed Finch, or Sydney Waxbill as it have to feed in the open, they, too, given to those birds of the genus is otherwise known. rely on the grass seeds and its har­ Btrilda that were early imported into Clearly, it is impossible to define bored community of tiny inhabitants - Europe (or at least one of them, most exactly what does constitute heing a aphids, bugs and beetles. likely the Common Waxbill E. astrild) waxbill and, therefore, it would he To survive, the grass and its insect and which possessed red bills resem­ unwise to exclude any of the species community need water, and this bling the sealing wax used on letters just mentioned. Rather, it would be comes with the rains. During and after and documents of the time. Thereafter prudent to lump them all together, rainfall the grass immediately under­ the name began to be applied to all accept that there are some "good" goes a remarkable transition. Green other species, with or without red bills, waxbills among them and, for the rest, leaves are produced in only a day or that were thought to be fairly closely to include them as allies. That is what so, followed by fresh ripe and half-ripe related to them, such as cordon-bleus, I have done here. seeds. The insects, with succulent veg­ firefinches and avadavats. In Australia, etation to munch and sap to suck, are largely because of their red bills, what Behavior fast stirred into action. So, too, are the is now known as the Red-browed Grass Dependency waxbills. With food of the right kind Finch Aegintha temporalis and, some­ Although waxbills are primarily now available in abundance, they are ·times, the Zebra Finch Poephila guttat- seed-eaters not every species relies on stimulated to breed. ta were typically thus labeled. grass seed for its subsistence diet, eating Hard seeds, which are unlikely ever Gradually, however, "waxbill" came to other plant seeds instead. Nevertheless, to be as hard as the commercial kiln- 40 July/August 2000 dried type, are overlooked in favor of seeds partly or largely through its feeding on the ripe and half-ripe ones, while the • Taking culm in beak and placing termites. It is possible other arid coun­ numerous insects make easy pickings under foot. try species do likewise. for a growing family of hungry As is found with most other birds, nestlings. Protein is essential for the b) Invertebrate Food waxbills usually drink by dipping the rapid healthy growth of the young and • Picking off substrate bill into the water then lifting the head that found in seeds is augmented in • Breaking open earthen termite gal­ and tilting it back to swallow, but the quick and easily assimilated form leries on substrate some are also able to suck up water that only a soft-bodied insect can pro­ • Moving sticks or bits of cattle dung, pigeon-fashion. In such a case the bill vide, and which the parents are able to etc., under which termites are work­ is kept in contact with the water for a regurgitate to their offspring quickly ing. longer period and without the need for for optimum results. Of additional • Perching on stem and breaking the head to be repeatedly lifted. benefit to the chicks is that they are, in open earthen termite galleries on tree Generally, the sucking method is used fact, getting two meals for the price of trunks or branches. when there is a small and/or shallow one, because the insect's gut will • Perching on termite chimneys and area of water, such as a droplet inevitably contain some nutritious taking termites working inside. remaining on the leaf of a plant not undigested plant matter. • Perching on termitaria and taking long after it has rained or been termites working on outside. sprayed. Estrilda and cordon-bleu Feeding Postures • Hawking termites from ground. species are particularly adept at apply­ Skead (975) describes the feeding • Hawking insects from perch. ing the sucking method. postures of four different species of • Feeding on insects high in trees. All waxbills love to bathe in water, waxbill he studied in the wild and though it is not known how frequent­ which can be applied to the group as Newton (973), in his classic work ly this action is performed in the wild. a whole. While not every individual on the true finches, the Fringillidae, Captive birds tend to bathe daily and, species performs every posture they all illustrates six different feeding posi­ providing there is enough surface undertake some of them, and the tions undertaken by species in this water, the likelihood i~ the wild bird Estrilda species, in particular, are able family. These are: a) standing; b) in a does also. For example, 10 minutes to perform most. The feeding methods normal perching position on a plant­ after a summer thunderstorm had are classified as: stem; c) leaning forwards; d) perching passed Skead (975) observed a on a bent plant-stem, so that the bird's Green-winged Pytilia or Melba Finch, a) Grass-seeds centre of gravity lies over one of its Pytilia melba, bathing in a roadside • Standing on ground feet; e) clinging to a vertical stem; 0 pool where previously there had been • Feeding from substrate. hanging upside down. no water. • Digging into substrate with bill­ In addition, he states that the Bathing usually starts off with some sweeping movement. Chaffinch, Fringilla coelebs, and hesitation and apparent nervousness, • Taking grass culm (stem) in beak Brambling, F. montifringilla, some­ possibly a reaction to a fear of lurking then placing under foot. times chase and catch flying insects, predators or the uncertainty as to the • Taking seeds directly from inflores­ and the Bullfinch, Pyrrhula pyrrhula, depth of the water. Once a bird starts cence.
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