The Greater Racket-tailed Drongo, Dicrurus paradiseus, is a medium-sized Asian bird. The drongos are passerines restricted to the Old World tropics. They were previously classed as the family Dicruridae, but that has been much enlarged to include a number of largely Australasian groups, such as the Australasian fantails, monarchs and paradise flycatchers.
The Greater Racket-tailed Drongo is a resident breeder in tropical southern Asia from Kashmir, India and Sri Lanka east to Indonesia. This species is usually found in broadleaved forest. Three or four eggs are laid in a cup nest in a tree.
Race grandis with growing outer tail feathers.
These are aggressive and fearless birds, 32 cm in length, and will attack much larger species if their nest or young are threatened. This aggressive drongo is often found in mixed feeding flocks typical of Asian jungle habitats. They are said to imitate raptor calls so as to alarm other birds and steal prey from them.
The adult Greater Racket-tailed Drongo has spangled metallic green-blue plumage, and a large bill. The tail is long and shallowly forked, with the shafts of the two outermost feathers greatly extended and ending in the rackets which give this species its name. The racket is formed by the inner web of the vane but appears to be on the outer web since the rachis has a twist just above the spatula. There is a head crest, prominent in the Indian race, D. p. grandis, but much reduced in some other subspecies. The young bird is duller and uncrested.
Their courtship display may involve hops and turns on branches with play behaviour involving dropping an object and picking it in mid air.
The Sri Lankan form, D. p. ceylonicus, has a smaller crest and has a long deeply forked tail without rackets. It is sometimes given specific status as Dicrurus ceylonicus.
The Greater Racket-tailed Drongo has short legs and sits very upright and often perches on exposed branches. It is insectivorous. They chase Shikras but rarely pursue crows or kites in the manner of Black Drongos. A special alarm note is raised in the presence of Shikras that has been transcribed as a loud 'kwei-kwei-kwei...shee-cuckoo-sheecuckoo-sheecuckoo-why!'. They begin calling from as early as 4 am in moonlight often with a metallic tunk-tunk-tunk series. The species is well-known as a very accurate vocal mimic, able to learn its alarm calls through interactions in mixed-species flocks. This is quite unusual, as avian vocal mimicry has hitherto been believed to be ignorant of the original context of the imitated vocalization (parrots are known to use imitated human speech in correct context, but do not show this behavior in nature). This drongo's context-sensitive use of other species' alarm calls is thus analogous to a human learning useful short phrases and exclamations in a number of foreign languages. Jim Corbett in his book "Jungle Lore" mentions that the Drongo can imitate to perfection the calls of most birds and the Cheetal Axis axis. He noted that they associated with ground-feeding birds and kept a look out for predators. This observation has also been noted in more recent scientific studies. In some places they have been found to be kleptoparasitic on other members of the mixed species flocks, particularly Laughingthrushes but they are most often involved in mutualistic and commensal relations.
- ^ Styring, AR & Kalan Ickes (2001) Interactions between the Greater Racket-tailed Drongo Dicrurus paradiseus and woodpeckers in a lowland Malaysian rainforest. Forktail 17:119-120 PDF
- ^ Harsha, S; K Satischandra, EP Kudavidanage, SW Kotagama & E Goodale (2007) The benefits of joining mixed-species flocks for Greater Racket-tailed Drongos Dicrurus paradiseus. Forktail 23: 145"?148 PDF
- ^ Bourdillon, T. F. (1903) The birds of Travancore J. Bombay Nat. Hist. Soc. 15(3):455
- ^ Ali, S. (1929) The racket-feathers of Dissemurus paradiseus. JBNHS 33(3):709-710
- ^ a b Neelakantan, KK (1972) On the Southern Racket-tailed Drongo Dicrurus paradiseus paradiseus (Linn.) J. Bombay Nat. Hist. Soc. 69(1):1-9
- ^ Goodale E, Kotagama SW. (2006). Context-dependent vocal mimicry in a passerine bird. Proc Biol Sci. 7;273(1588):875-80.PubMed
- ^ Goodale, E., Kotagama, S.W. 2008 Response to conspecific and heterospecific alarm calls in mixed-species bird flocks of a Sri Lankan rainforest. Behavioral Ecology 19 (4):887-894
- ^ King, DI & JH Rappole (2001) Kleptoparasitism of laughingthrushes Garrulax by Greater Racket-tailed Drongos Dicrurus paradiseus in Myanmar. Forktail 17:121-122 PDF