The Belligerent Bird - Black Drongo
When it comes to "birdwatching", most people would choose winter, as that is when a large number of birds fly from the cold north to spend the winter. However, even in summer, some birds that fly from the south to the north can still be seen in Hong Kong, and the Black Drongo (Dicrurus macrocercus) is one of the most common local summer migratory birds. They are relatively small and slender in body size, but they are very tough and belligerent, and even raptors like the Black Kite often flee in panic when confronted by them!
The Black Drongo is entirely black in colour, which may seem "low-key", but its "all-black" appearance makes it stand out even more. Moreover, it has a long tail with a forked end that curves slightly backward, making it easily recognisable from a distance. The Black Drongo has a strong beak that is slightly hooked at the front, which is helpful for catching insects and other small animals.
In terms of distribution, the Black Drongo is widely found across Asia, including India, Southeast Asia, mainland China, and Taiwan. In Hong Kong, it is commonly seen in open fields and sparse woodlands in the lowlands. They like to perch in conspicuous places, and their favourite perches are power lines. They have a loud call that makes them very noticeable.
The Black Drongo usually perches at a height of 3 to 12 metres. They hunt for food by "aerial hunting", swooping down a few meters from their perch to catch flying insects. Like many carnivorous birds, the Black Drongo compresses indigestible food residues (such as hard shells) into pellets after eating and regurgitates them from its mouth. Research in India analysing the pellets of Black Drongos found that they most frequently prey on the insect Order Coleoptera (beetle), followed by insects Order Hemiptera (bugs) and Order Hymenoptera (bees).
Small Groups Join Forces to Chase and Attack Big Birds
The Black Drongo usually appears alone or in pairs, but during the breeding season, they form small groups. They are highly territorial, especially during breeding and nesting periods. When they detect an intruder in their territory, they will actively attack. Even when facing the Large-billed Crow (Corvus macrorhynchos), which is several times larger, or even the Black Kite (Milvus migrans), they will not retreat. Small groups of Black Drongos often aggressively drive away these big birds, causing them to finally flee in panic.
In ancient Chinese texts or poems, the characters "Pi Ji", "Ji Jiu", "Wu Jiu", "Ya Jiu", and "Bei Jia" were used to refer to Black Drongos, and there are also early records of scenes of them driving away larger birds. The ancient book "Eryayi" Volume 16 describes them as "smaller than a crow but can drive away crows; commonly known as the crow's uncle", pointing out that although the Black Drongos are smaller in size, they can drive away crows, and that only an uncle of crows could do so. It seems that the ancient name of "Wu Jiu", "Ya Jiu" (both meaning "Uncle Crow" in Chinese) for Black Drongos originated from this. According to Taiwanese records, the Black Drongo will even drive away humans who approach their nests, which shows how aggressive they are in personality, having no fear of humans!