 There
are barbets in the tropics around the world. Barbets in the Old Word are
here treated as two separate families, African Barbets [Lybiidae] and Asian
Barbets [Megalaimidae]. The Asian barbets are chunky, mostly small to mid-sized,
often colorful and vocal birds of the Oriental tropics. The call of the
Coppersmith
Barbet (left; at a nest hole), for example, is a dominant sound of
Asian woodlands. In some tracts of woods the "hammering" sound of these
barbets (thought to recall a coppersmith at his trade) is present dawn
to dusk. Nest holes, like this one, are excavated in rotten trees. The
2-5 eggs will be incubated for about two weeks; thereafter both parents
care for the young. The zygodactyl feet (two toes forward, two backward)
are adapted for clinging to trees, like woodpeckers, but unlike them the
tail feathers are not stiffened.
Coppersmith Barbet is by far the most widely distributed Asian barbet, occurring from India to Indonesia and the Philippines. It is also the only non-forest barbet in Asia; the remaining 25 species require tracts of extensive jungle — those barbets hard to see although easy to hear. Their calls can dominate forests from steaming lowland jungle to montane cloud forests. Among them are a number of highly-sought endemics. |
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 There
are 9 barbets on Borneo, but three of them are Bornean endemics in the
mountains. Despite two trips, I've managed to see only one of these (although
I've heard all three). That lone endemic is the striking Gold-naped
Barbet (right and below). On our last visit, my wife Rita Carratello
obtained video of a calling Gold-naped in which the male vibrated a bulging
air-sac on its neck when it gave its strident, hollow took-took-tarrroook
calls over and over again [Rita Carratello video-cap below].
I cannot find this behavior and anatomical oddity — recalling the neck
sacs of booming grouse — mentioned anywhere in the literature.
|
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 All
but two of the Asian barbets are consigned to the genus Megalaima.
The Great Barbet Megalaima virens of the Himalayan forests is much
larger than others in this family. At 273 grams it is more than 7 times
heavier than the Crimson-throated Barbet M. rubricapilla of Sri
Lanka. The exceptions are the Fire-tufted Barbet Psilopogon pyrolophus
of Malaya and Sumatra and the Brown Barbet Calorhamphus fuliginosus
of southeast Asia. Fire-tufted Barbet (left in a fine shot by Hideo
Tani) is a striking bird that has a vague resemblance to Toucan-Barbet
of the New World (in its and differs from Megalaima barbets by its
graduated tail and its facial bristles in distinct nasal tufts.
As to Brown Barbet, it is dull-colored, uniformly brown species that nests colonially; it also lacks the vocal repertoire of boops and trills of other Asian barbets, giving only a wheezy whistle (Short & Horne 2001). Prum (1988) and Barker & Lanyon (2000) initially found that molecular evidence did not group Brown Barbet with other Asian barbets. Short & Horne (2002) used with evidence as a "major stumbling block for those who would recognize three barbet families, one for each continent" (see below). But Moyle (2004) used three different molecular methods and undertook three different types of analysis, and showed flaws in the early studies. A mis-choice of analytical methods (e.g., parsimony alone) has the tendency "to unite taxa on long branches even when not closely related." It appears that Brown Barbet does, indeed, group with other Asian barbets, thus removing the "stumbling block" to our family arrangement here. |
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Brown-headed Barbet (right) is a typical Megalaima barbet of the Himalayan foothills. Biochemical studies of mitochondrial DNA (Lanyon & Hall 1994) and DNA-DNA hybridization (Sibley & Ahlquist 1990) led to proposals that the barbets be separated into three different families: Asian Barbets (Megalaimidae), the African Barbets (Lybiidae), and the American Barbets (Capitonidae, which would include toucans). Recent genetic data (Moyle 2004) support the monophyly of the barbet radiations within each region. To emphasize the close relationships among New World taxa, the three groups there — New World barbets, toucan-barbets, and toucans — were treated as subfamilies of a single family, Ramphastidae, by AOU (1998). This approach means that the Toucans are lost as family and they become just "big-billed barbets." I know that from the perspective of a world birder, toucans are a distinctive group, easily recognized as toucans and nothing else, and that they are exciting birds to see. I like the idea of Toucans as their own family. The Handbook of the Birds of the World (Short & Horne 2002) sticks with the traditional approach of two families: all the barbets (including Toucan-Barbets) in a barbet family and the toucans in a toucan family. That does separate out the Toucans, but misstates their evolutionary relationships. I prefer a more modern approach now taken by the South American Checklist Committee. They split the New World groups into three families (including the distinctive Toucan-Barbets; Barker and Lanyon 2000, Moyle 2004) and have separate families for the Asian and African barbets that are not as closely related. Under this method the two old families (barbets, toucans) become five new families. Use the links below to see the other other four families:
|
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 Whatever
taxonomic approach is preferred, Asian barbets are important components
of the tropical forests of the Orient. They provide, in good measure, the
"sound track" of these jungles. They widely disperse seeds and pollen as
they eat fruit, catkins, and flowers, and their used nesting holes can
be used by other creatures. Gold-whiskered Barbet (left), for example,
has a big, heavy bill for hammering at soft wood, both for food and for
nests and shelter. Tropical barbets are decline with the loss of lowland
and montane forests. Of particular concern for barbets is the intensity
of the human need for dead wood, the removal of which eliminates nesting
sites. Even selective logging in southern Asia removes host trees of strangling
fits, and thus the figs themselves, a primary barbet food (Short &
Horne 2002). Pressure from the cage-bird trade is another problem in some
areas; Fire-tufted Barbet is a particularly desired. We can only hope that
the Asian barbets and their diversity will survive man's pressure on their
habitats. |
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| Photos: The Coppersmith Barbet Megalaima
haemacephala was at its nest hole near Bislig, Mindanao, Philippines,
in March 1990. Both photos of Gold-naped
Barbet M. pulcherrima
were taken on Mt. Kinabalu, Sabah, Malaysian Borneo, in July 2003; that
by Rita Carratello is a video capture. Hideo Tani photographed
the Fire-tufted Barbet
Psilopogon pyrolophus at Frasers Hill, Malaysia, in Feb 2003. The
Brown-headed
Barbet Megalaima zeylanica was at Ramnagar, Uttar Pradesh,
India, on 13 Mar 2001. The
Gold-whiskered Barbet
M. chrysopogon was at Ketambe, w. Sumatra, Indonesia, on 18 Aug 1988.
Photos
are © 2004 Don Roberson and Hideo Tani, used with permission; all
rights reserved.
Photos of over a thousand species by Hideo Tani can be seen on his web site. Family Book: Rating: I must confess that I don't actually own this book, nor have I done more that quickly glance through it in a bookstore. But every one of the Oxford Univ. Press series on bird families has been excellent, and this looks equally solid. I presume that the "meat" of this book has been summarized by the same authors in their Handbook of the Birds of the World series (Short & Horne 2002) which I do own and have studied.Literature cited: American Ornithologists' Union. 1998. Check-List of North American Birds. 7th ed. A.O.U., Washington, D.C. |
