a web page by Don Roberson |
VANGAS Vanginae |
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| Many of the vangas, including Sickle-billed Vanga, often associate with other birds in mixed species flocks working through the forest. All the vangas require woodland of some type — from thick humid jungle to dry open spiny forest — and so are good indicators of the presence of native habitat. Several of the vangas are the "core" species of these foraging flocks. The Lafresnaye's Vanga (above) is different. It does not join flocks but forages alone or in small single-species flocks. Its The flight is powerful (the one above right is just taking off) between foraging sites, and then it works the dead tree from bottom up, "spending much time to remove bark, often working with head pointed down" (Langrand 1990). | ||
All of the vangas prey on invertebrates or small herps to one degree or another. Some have evolved heavy wedge-like bills for breaking off bark, like that of Van Dam's Vanga (right), a species restricted to deciduous forest of the northwest where it is rare and local. One species fills the niche of a chickadee (Red-tailed Vanga Calicalius madagascariensis), another that of a nuthatch (the Nuthatch Vanga Hypositta corallirostris looks so much like a nuthatch that its alternate name is "Coral-billed Nuthatch), and yet another has a huge casqued bill, recalling hornbills, and is known as the Helmetbird Euryceros prevostii (it is also the most remote species, restricted to extreme northern Madagascar). |
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Taxonomically, the vangas were thought to be related to African families such as the helmetshrikes, wattle-eyes and batises (indeed, Sibley & Ahlquist 1990 and Sibley & Monroe 1990 lumped all these groups together) but most authorities considered them a separate family (e.g., Dickinson 2003). Then newer molecular evidence (e.g., Fuchs 2004) showed that these closely related groups fall into three different clades: the batises and wattle-eyes in one group, the traditional bush-shrikes in another group, and the helmet-shrikes, vangas, and flycatcher-shrikes in the third group. When I wrote this page initially in 2005, I said that "These data show that helmet-shrikes and vangas are very closely related, and it possible that in the long run these two families may be grouped together." For a time I retained vangas as an endemic family to Madagascar. But the most recent evidence (Reddy et al. 2012, Jønsson et al. (2012) is that vangas are best considered a subfamily of a broader vangid assemblage.
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However, what constitutes a vanga has changed recently. The initial 14 was enlarged by a third, to 21 species (more on that just below). The newest paper [Reddy et al. 2012] showed that vangas and their close relatives diverged from their shrike-like relations about 24 million years ago (mya) and these ancestors reached Madagascar about 20 mya. Then they rapidly evolved and diversified in bill size, foraging behavior, and filled niches in previously unused habitats. The vangid relatives on the continents of Africa and Asia did not diversify nearly as much, but the lineage leading to the Madagascar vangas — helmet-shrikes, woodshrikes, Philentoma 'flycatchers' and others — together form a monophyletic group.
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Photos: The Sickle-billed Vanga Falculea palliata was near Ishfay, north of Tulear, southwestern Madagascar, on 20 Nov 1992. The Lafresnaye's Vanga Xenopirostris xenopirostris was in that same spiny forest the same day. The Van Dam's Vanga Xenopirostris damii was photographed at Ankarafantsika in the Ampijoroa Forest on 29 Nov 1992. The Chabert's Vanga Leptopterus chabert was near Perinet, in eastern Madagascar, in mid-Nov 1992. I sketched Crossley's Vanga Mystacornis crossleyi at Perinet on 2 Dec 1992. Photos & sketch © Don Roberson; all rights reserved. Bibliographic note: There is no "family book" per se but good photos of all vangas (even the new ones) are in Morris & Hawkins (1998), and their habitats covered by Dee (1986). A fine introductions to this (now) subfamily, with spectacular photos, is in Yamagishi & Nakamura (2009). Literature cited:
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Traditionally,
vangas were considered to be an endemic family to Madagascar, with just
14 species, but the number of species has expanded with recent
discoveries. This island family arose in isolation and birds evolved to
fill numerous niches. Jønsson et al. (2012) provides molecular
evidence that this diversification arose rapidly within the last 10
million years and is as dramatic as the better known (and younger)
diversifications that occured in the Hawaiian Honeycreepers or the
Darwin's Finches of Galapagos
Another,
Chabert's Vanga (left) forages with mixed species flocks and sallies
out like a small flycatcher, or glides like a small wood-swallow.
Although difficult to see in this shot, it has bare blue skin around
its eye (like the wattle-eyes of Africa). 
As to the vangas of Madagascar themselves, Yamagishi et al. (2001) found that Tylas Tylas eduardi was indeed a vanga (some had once postulated it was a bulbul) but more surprisingly, they found that birds in the genus Newtonia were also vangas. There are four species — Common Newtonia N. brunneicauda, Dark Newtonia N. amphichroa, Archbold's Newtonia N. archboldi, and Red-tailed Newtonia N. fanovanae
— so this immediately increased the vangas by 28%. Then Cibois et al.
(1999, 2001) did molecular work on other Malagasy endemics and found
many surprising things. One of them is that Crossley's Babbler Mystacornis crossleyi is not a "babbler" at all; it is a vanga (Schulenberg 2003). So is Ward's Flycatcher Pseudobias wardi (Schulenberg
2003, Dickinson 2003). So this brings the vangas in Madagascar to 21
species. [My field sketch of Crossley's "Babbler" is to the right].