[order] CICONIIFORMES | [family] Ardeidae | [latin] Gorsachius melanolophus | [authority] Raffles, 1822 | [UK] Malayan Night Heron | [FR] Bihoreau malais | [DE] Wellenreiher | [ES] Martinete malayo | [NL] Indische Kwak
| Genus |
Species |
subspecies |
Region |
Range |
| Gorsachius |
melanolophus |
|
OR |
widespread |
Genus
Gorsachius is a genus of Old World night herons typically found near water in forested regions. These are medium-sized herons which are migratory in the colder parts of their ranges, but otherwise resident. They are the least known, most strictly nocturnal, smallest and overall rarest night herons. Three of the four species are found in East, South and South-east Asia, while the last species, the White-backed Night Heron, is found in sub-Saharan Africa. The Japanese and Malayan Night Herons resemble each other, being relatively short-billed and overall brown with a dark line from the throat to the upper belly. The larger White-eared and White-backed Night Herons are darker, with distinctive white markings on the face and neck in the former, and an entirely black head in the latter. While generally nocturnal and crepuscular, they have been recorded feeding during the day in clouded weather
Adults have black crowns, and are reddish-brown overall, with dark reddish-brown underparts with fine streaks, and black underwings. The adults also have blue lores on the face, which can vary in colour after moulting. The sexes are similar, though males may have a darker crest and some birds, especially females, may retain juvenile plumage. The juvenile is greyish-brown with black and white spots, and its underparts are streaked.
Listen to the sound of Malayan Night Heron
[audio:http://www.planetofbirds.com/MASTER/CICONIIFORMES/Ardeidae/sounds/Malayan Night Heron.mp3]
Copyright remark: Most sounds derived from xeno-canto
recorded by Chie-Jen (Jerome) Ko
| wingspan min.: |
0 |
cm |
wingspan max.: |
0 |
cm |
| size min.: |
48 |
cm |
size max.: |
50 |
cm |
| incubation min.: |
0 |
days |
incubation max.: |
0 |
days |
| fledging min.: |
0 |
days |
fledging max.: |
0 |
days |
| broods: |
1 |
|
eggs min.: |
3 |
|
| |
|
|
eggs max.: |
5 |
|
Oriental Region : widespread. The Malayan Night Heron ranges from India east to the Philippines and
south to the Greater Sundas.
It inhabits lowland wooded swamps, streams and marshes in tropical and subtropical forest in areas of heavy rainfall. The nesting areas in Taiwan are mostly in low-altitude forests, consisting of tall trees and bamboo, often close to human residences, with suitable open places for feeding.
The female Malayan Night Heron lays 3-5 eggs and does most of the incubation. Both parents feed the young. Third-party birds may sometimes attempt to help raise the young, but are often chased away by the parent birds. Some parent birds have been known to have immature plumage; most of these appear to be females.
They feed mostly on earthworms and frogs but rarely on fish. It is a spectacle to see them probing for and tugging out big earthworms (10 x 300 mm) from the soil. They usually nip off the worm’s head by vigorous shaking and then swallow both parts after a few minutes. A peculiar behaviour pertinent to the ingestion of earthworms involves exaggerated, slowly repeated peristaltic movements of the neck.
Video Malayan Night Heron
httpv://www.youtube.com/watch?v=rGscD0Xosis
copyright: Martin Kennewell
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). The population size may be small, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Little known. Partial migrant: population of SW India apparently migrates in Oct/Nov to Sri Lanka; birds from N India and Burma move S in Aug-Oct, probably wintering in Malay Peninsula and Greater Sundas, where may be joined by birds from Thailand and Indochina which are absent from breeding areas between Oct and spring; passage through May Peninsula note in Oct-Dec and Apr; wintering birds in Sumatra Nov-May. Post-breeding dispersal of E populations to Taiwan and Ryukyu Is, where species overlaps with wintering G. goisagi, as in Philippines, where present species sedentary. vagrant to Shikoku Is (Japan), Palau Is, Banggai Is (off NE Sulawesi) and Christmas I (Indian Ocean)
