The Avicultural Society

THE TRI-COLOURED MUNIA AND THE CHESTNUT MUNIA - TWO GOOD SPECIES?

By Robin L. Restall, Hong Kong
First Published in The Avicultural Magazine Vol. 100 No. 4
Copyright © 1994 Avicultural Society, Published with Permission

In his seminal revision of the subfamily Estrildinae in 1943, Jean Delacour united three separate munia species into one. The three were Tri-coloured MuniaLonchura malacca, Chestnut MuniaLonchura atricapillaL. atricapilla and Lonchura ferruginosaL. ferruginosa. He gave the name ferruginosa for the combined species, over-looking the fact that Loxia malacca Linnaeus (1766) antedates Loxia ferruginosa Sparrmann (1789). Since then several authors have questioned the wisdom of this. Wolters (1979) regarded L. ferruginosa as a good species and Sibley and Monroe (1990) follow him. Goodwin separated L. malacca, L. atricapilla and L.ferruginosa into three groups but retained them as a single species, other writers generally follow suit, but there is a trend to regard L. ferruginosa as a good species, e.g. MacKinnon and Phillipps (1994). The specific integrity of L. ferruginosa now appears to be beyond doubt and I certainly feel it should be treated as a good species. Considering the detail of all this and regardless of the status of L. ferruginosa, I have come to the conclusion that L. malacca and L. atricapilla must be regarded as distinct species. The reasons are as follows.

The Tri-coloured Munia L. malacca occupies a clearly demarcated range within India, quite separated from L. atricapilla by a strip of land some 250 km between the two at the closest point (Au and Ripley 1987). In contrast, L. atricapilla has an extensive sprawling range within which various sub-species intergrade and even overlap.

Within L. malacca there are five distinct morphs, by far the commonest being the familiar black-headed chestnut-backed bird with a white breast band and white flanks, and a clearly-defined black belly patch running into black undertail-coverts. This form accounts for 95% or more of any population. The first of the four variants has a noticeably irregular zig-zagging of the division between the black and the white on the flanks. The second has a fine wavy black barring over the white feathers similar in pattern to that on the African Silverbill L. cantans. The third has a very light cinnamon wash over the white with the edges of the feathers darker cinnamon, giving a scalloped appearance; and the fourth has the white replaced by an even cinnamon. Obviously the species has a propensity for colour variation on the white. Only one of these resembles L. atricapilla, and that is the cinnamon-flanked variant. But when compared side-by-side, the cinnamon flanks of this form of L. malacca do not match any of the variations of L. atricapilla.

In contrast there is considerable variation within the different geographic forms of the Chestnut Munia L. atricapilla. The different races have varying shades of brown on the upper surfaces, including a pale scalloping on the mantle. There are also different shades of brown on the breast and flanks, and a considerable variety of colouring of the rump, uppertail-coverts and tail. In addition there are variations of head colouring, both from race to race and sometimes within a race, from black to brown and even pale grey on the nape. The belly varies from an extensive irregular black to a total absence of black, the belly and vent to undertail-coverts being the same brown as the flanks. In all this variation, within which there arc many confusing intergrades and some abrupt contrasts, there is no clear trend nor dine. All the variation is of the black and brown.

More significantly there are no cases of morphs showing white anywhere on the body, let alone on the breast and flanks.

Although I have not been able to hold live nestlings side by side for direct comparison, it appears that the palate markings of L. malacca are different from those of L. atricapilla.

In my experience, in behavioural terms L. malacca and L. atricapilla self-select for partners and pair bonding, in preference to crossing or mixing both in the wild and in captivity. Both species occur in Hong Kong where L. atricapilla is a migratory summer visitor, and the introduced L. malacca is a resident. Mixed pairs have not been recorded. It has been reported that intermediates between the two species occur (Viney et al 1994) but I understand from Clive Viney (in litt) that this conclusion was based on observations of seeing both species entering the same reed beds carrying nesting material. These would almost certainly have been male birds in every case, with which cross-breeding is unlikely. It would be impossible to divine the parentage of juveniles or moulting first year birds without seeing fledglings being fed by the parents. It seems certain that the two species do not interbreed in Mai Po.

In the light of his reasoning I find a case for regarding L. malacca and L. atricapilla as separate species irresistible. I am certain that there are members of the Avicultural Society who will have some experiences or observations that could bear on the subject, one way or the other. I would be most grateful for any input however insignificant it might seem. Please write to me care of the Editor.

Incidentally, there is a plumage variant known in L. ferruginosa. This differs from either of the foregoing species. It is only found on the male and has the black of the underparts extending from the bib right to the undertail-coverts with little or no chestnut on the flanks at all (and that covered by the folded wings). It would be invaluable to see the palate markings of the nestling L. ferruginosa. Does anybody know of a reference please?