Drongo: The kotwal among birds

New Delhi, December 28

A glossy black bird with a distinctive forked tail and perched on a bare branch was looking for something when it suddenly flew and we next saw him hovering over a Tawny eagle, more than twice his size and much stronger. But our bird, known as the black drongo was unfazed and fearlessly fighting off the eagle from his territory. The drongo kept dive-bombing without any hesitation and the eagle eventually made off.

Despite their small size, the black drongos are aggressive and fearless. They display mobbing behaviour and routinely attack birds of prey when their nests or young are threatened. It is also called the king crow, not because he is "as black as a crow" but because of this bird's courage to put crows, even kites and eagles, to flight should they venture out to plunder eggs and hatchlings.

Their aero-acrobatics are something to behold! Other birds such as bulbuls, doves, orioles and mynahs prefer nesting in the vicinity of drongos just to gain protection. And, this is the reason they are also referred to as 'kotwal' (policeman) in Hindi. The little bird gives a fierce, shrill screaming and shoots out like an arrow from a bow. Its aim is true, its beak sharp and the target is the back of the lawbreaker.

With the 24-hour security service that comes with the location, birds hatch their eggs in peace.

One of the best descriptions of the drongo's aggression can be found in the colonial-era civil servant and naturalist Edward Hamilton Aitken's book, 'The Common Birds of Bombay', published in 1900.

In his characteristic humourous style, Aitken writes: "(The king crow) has nothing to do with crows save to vex their lives. The occasion for that is generally its nest, which it builds on some outstanding branch of a conspicuous tree, scorning concealment. Round this it establishes a 'sphere of influence', and the Crow, being a notorious poacher and damaged character, is forbidden to enter that.

"But the Crow is always sounding the depths of our patience with the plummets of insolence, and it will try the experiment of flying lazily past the King Crow's nest, or even alighting on a neighbouring tree. Then the little bird gives a fierce, shrill scream, and shoots out like an arrow from a bow." The crow is big enough to carry off its puny enemy and pick its bones, if it could catch it, but who can fight against a 'bolt from the blue'? The first onset may, perhaps, be dodged, but the nimble bird wheels around, rises and plunges again with derisive screams, piling pain and humiliation on the enemy far beyond the limits. Then the king sails slowly back to its tree and resumes its undisputed reign.

Apart from the swift balletic dives, nothing about the drongo's physical appearance – the small squat body, the glossy black feathers or even the distinctive forked tail, that measures about 28 cm in length, is spectacular. But to merely glance and ignore this bird is to lose sight of a bird that is truly remarkable, fearless and aggressive.

These 'kotwals' have a big attitude. Often found in mixed species flocks throughout their range, these glossy black birds are renowned for their ability to mimic other birds with an accuracy that can confuse bird watchers. We have nine species of the drongo and all come in wholly glistening black plumage except for the white-bellied drongo and the ashy drongo. They are comparable to the dove in body size but with a much longer tail, ending in a deep, wide fork, however, the most frequently sighted is the black drongo.

Drongos have adapted themselves to human habitat. Burning farm lands give them an opportunity to capture insects. It is known to swoop on insects during flight and is famous for its daredevil stunts. The agile bird will manoeuvre inside and across fire flames catching fleeing insects on the move. The extreme heat generated by the fire makes it impossible for one to stand but our bird which has adapted to the phenomenon easily follows the flames. Its slender body, long and forked tail aid to aerial acrobatics and help in snagging escaping insects. The voracious behaviour of the bird has proved important for biological control agents controlling pest through natural processes of prey and predator without disturbing the ecological cycle.

This cunning nature of the drongo has fascinated scientists, as these birds may possess what scientists call the "theory of mind". This is the ability of an animal to strategically plan and manipulate others – a trait only found in humans. According to scientists, drongos spend 90% of their day following other animals to mimic the sound that other animals make. They will then use this to their advantage in a number of ways. They'll make a flock of birds believe that they are part of the same flock, they'll call animals away from food and then steal it for themselves and they will gather species around them to protect themselves from larger predators.

They wait for these smaller species to find food and then make use of deceptive mimicked alarms to steal the food! Animals like the dwarf mongoose will never ignore alarm calls, even if that means that they drop their insect catch and flee to safety. In short, they are brilliant birds, just don't give them a flame!  IANS

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