Mar 20, 2019
Tai Po Kau Biodiversity
by Thomas Gomersall
Just a 30-minute drive south of Tai Po town lies Tai Po Kau Nature Reserve. Although hard to believe now, the area was once a barren wasteland, thanks to uncontrolled deforestation and burning. But in 1926, the Hong Kong government began a programme of large-scale afforestation of the New Territories and as a result, Tai Po Kau is now 460 acres of dense, mature woodland with more than a hundred tree species, both native and introduced. It’s hardly surprising then that it is widely considered to be one of the best places in Hong Kong to see forest birds and to study woodland ecology. Aside from that, it’s also extremely peaceful. Just a few minutes’ walk along one of the winding hillside paths and soon the rumble of the highway gives way to the soft hoots of monkeys and the gentle chirping of birds.
Scarlet minivet (Pericrocotus speciosus): Usually in sexually dimorphic birds, males are the ones with bright colours and/or unusual plumage to attract mates while females tend to be drab and dull-coloured to avoid detection by predators. In the scarlet minivet however, the dazzling black and orange-red male is equally matched in beauty by the grey and bright yellow female. A winter migrant to Hong Kong, these birds tend to move through the trees in flocks of 10-30 in search of insects to eat. As well as their plumage, they can also be identified by their loud, shrill whistles of ‘sweep-sweep-sweep-sweep’.
Chestnut bulbul (Hemixos castanonotus): Although a small population of this bird lives in Hong Kong year-round, winter is the best time to see them when they are joined by migrant individuals from the north. Though not a great deal is known about this bird, it is still easily detectable thanks to its loud hooting call. It can often be seen in the upper branches of trees, where it feeds on berries and insects.
Hong Kong newt (Paramesotriton hongkongensis): At first glance, Hong Kong’s only salamander may seem unassuming with its largely dull brown body. But flip it on its back and you will find a bright orange belly covered in irregularly shaped black patches, the patterning of which differs between individual newts the same way fingerprints differ between humans. It lives in mountain streams across Hong Kong and is usually found in fairly slow-flowing water. Breeding occurs during the dry season from September to March to reduce exposure of the adults and young to fast-flowing water. Like many amphibians, the young are born with gills to help them breathe underwater and which gradually disappear as they mature. As they require clean water to survive and breed, pollution represents a considerable potential threat to this species.
Firefly (Family: Lampyridae): Typically, the animals that attract people to a protected area are large, charismatic mammals or colourful birds. But in Tai Po Kau, the animal that is perhaps the most well-known and most popular among visitors is the humble firefly. Each year large numbers of these beetles come out at night and flash their bio-luminescent abdomens to attract prey or a mate (May to August is the best time to see them). There are 20 species of firefly in Hong Kong and most of them can be found in Tai Po Kau, probably due to their preference for forested habitats with lots of water and rotting wood to hide in during the day.
Fairy pitta (Pitta nympha): Forest birds comprise some of Hong Kong’s most colourful species, and this bird is easily one of the most beautiful examples of that. But in spite of its cream breast, scarlet belly, green wings with a streak of electric blue and the fact that it forages almost entirely on the ground, the fairy pitta is a hard bird to see. For one, it is a winter passage migrant, meaning that there is only a very small window of opportunity to find it in Hong Kong. Even when it is around, its shyness, rarity and preference for dense undergrowth make it difficult to find. As such any sightings of one cause great excitement among the local birdwatching community. It feeds mainly on ground-dwelling invertebrates and is particularly fond of earthworms, probably because of their high energy content, which is useful for the bird to complete its migration.
