Many animals have unique ways of surviving in the wild. One example is the Golden-winged laughingthrush (Trochalopteron ngoclinhense). The bird has a shy nature, and prefers to hide within montane thickets. Because of the behavior, its presence is quite difficult to detect in its natural habitat.
The Golden-winged laughingthrush was first discovered on Mount Ngoc Linh in May 1996 by a research team led by Jonathan C. Eames, Le Trong Trai, and Nguyen Cu. The name ngoclinhense relates directly to its discovery site, which in the local language translates to "sacred jewel." Its natural habitat is now restricted to the montane forest areas of the Annamite Range, stretching across central Viet Nam and southern Laos.
Key Distinguishing Physical Traits
At first glance, the Golden-winged laughingthrush has a medium build with a body length of around 26 centimeters. Its upper breast to back is dominated by a dark gray color. As a contrast, the crown on top of its head is adorned with a reddish-brown pattern. The area around the eyes is black, while its ear coverts are gray.
The bird's main defining characteristic lies in the color pattern of its wings. Its flight feathers display a golden-yellow hue paired with jet-black primary coverts. The consistency of the color pattern served as a key clue for the researchers when they first discovered it.
The bird was initially thought to be a variation of the Chestnut-crowned laughingthrush (Trochalopteron erythrocephalus). However, the combination of golden wings and black coverts is not found in any other bird species in Indochina. Due to the distinct coloration, it was officially declared a new species. Its type specimen is preserved at the Natural History Museum in Tring, England.
Habits in the Understory
The bird lives in high-altitude montane forests between 1,480 and 2,200 meters above sea level, where the ecosystem is dominated by stunted, mossy trees. As a diurnal animal, all of its activities take place from morning to afternoon. The bird spends nearly all its time in the understory and rarely flies up into the high canopy or descends to open ground.
Its diet consists of small insects, soil invertebrates, and wild berries. While foraging, the bird gleans through leaf litter, mossy stems, and dense thickets. They often move in pairs or small groups, occasionally joining mixed-species foraging flocks to hunt together.
Visually, males and females look identical, which make them difficult to distinguish in the field. Because of its habit of remaining hidden within dense thickets, the bird's presence is more easily detected by its call than by sight. Group members typically keep their distance and coordinate with one another by exchanging two-note calls.
Threats to an Isolated Habitat
Due to its endemic nature, the bird is found only in the forest blocks of the Annamite Mountains. Based on mapping by The International Union for Conservation of Nature (IUCN) Red List, the species' range is recorded at around 590 square kilometers, but the actual forest area it occupies spans only about 65 square kilometers.
The IUCN Red List has categorized the species as Endangered since 2018. The assessment is based on a combination of its restricted range and the declining quality of the montane forest habitat it relies on. Meanwhile, the adult population is estimated to be around 2,499 birds.
Within its limited habitat, the bird faces population decline due to human activity. Forest clearing and land conversion for agriculture continue to destroy the understory vegetation where it feeds.
References:
BirdLife International. (2018). Trochalopteron ngoclinhense. The IUCN Red List of Threatened Species 2018. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T22728591A131518026.en
Eames, J. C., Trai, L. T., & Cu, N. (1999). A new species of laughingthrush (Passeriformes: Garrulacinae) from the Western Highlands of Vietnam. Bulletin of the British Ornithologists’ Club, 119(1), 4–15.
