Eastern Spot-billed Duck (Anas zonorhyncha)

Eastern Spot-billed Duck

[order] ANSERIFORMES | [family] Anatidae | [latin] Anas zonorhyncha | [authority] Swinhoe, 1866 | [UK] Eastern Spot-billed Duck | [FR] Canard de Chine | [DE] Chinesische Fleckschnabelente | [ES] Anade picopinto | [NL] Chinese Vlekbekeend


Genus Species subspecies Region Range
Anas zonorhyncha OR China, Southeast Asia


Anas is a genus of dabbling ducks. It includes mallards, wigeons, teals, pintails and shovelers in a number of subgenera. Some authorities prefer to elevate the subgenera to genus rank.[1] Indeed, as the moa-nalos are very close to this clade and may have evolved later than some of these lineages, it is rather the absence of a thorough review than lack of necessity that this genus is rather over-lumped. The phylogeny of this genus is one of the most confounded ones of all living birds. Research is hampered by the fact the radiation of the two major groups of Anas ? the teals and mallard groups ? took place in a very short time and fairly recently, roughly in the mid-late Pleistocene. Furthermore, hybridization may have long played a major role in Anas evolution, with within-subgenus hybrids regularly and between-subgenus hybrids not infrequently being fully fertile.[1] The relationships between species are much obscured by this fact, and mtDNA sequence data is of dubious value in resolving their relationships; on the other hand, nuclear DNA sequences evolve too slowly to resolve the phylogeny of the subgenus Anas for example. Some major clades can be discerned. For example, that the traditional subgenus Anas, the mallard group, forms a monophyletic (in the loose sense, i.e. non-holophyletic) group has never been seriously questioned by modern science and is as good as confirmed (but see below). On the other hand, the phylogeny of the teals is very confusing. For these reasons, the dabbling duck lineages more distantly related to mallard group (which includes the type species of Anas) than the wigeons should arguably be separated in their own genera. These would include the Baikal Teal, the Garganey, the spotted black-capped Punanetta group, and the shovelers and other blue-winged species. Whether the wigeons, which are very distinct in morphology and behavior, but much less so in mtDNA cytochrome b and NADH dehydrogenase subunit 2 sequences, should also be considered a distinct genus Mareca (including the Gadwall and Falcated Duck) is essentially the one remaining point of dispute as regards the question which taxa should remain in this genus and which ones should not.

Physical charateristics

These are mainly grey ducks with a paler head and neck and a black bill tipped bright yellow. The wings are whitish with black flight feathers below, and from above show a white-bordered green speculum and white tertials. The male has a red spot on the base of the bill, which is absent or inconspicuous in the smaller but otherwise similar female. Juveniles are browner and duller than adults. The Eastern Spot-billed Duck is darker and browner; its body plumage is more similar to the Pacific Black Duck. It lacks the red bill spot, and has a blue speculum

Listen to the sound of Eastern Spot-billed Duck

[audio:http://www.planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Eastern Spot-billed Duck.mp3]

Copyright remark: Most sounds derived from xeno-canto

recorded by Mathias Ritschard

wingspan min.: 83 cm wingspan max.: 95 cm
size min.: 55 cm size max.: 63 cm
incubation min.: 22 days incubation max.: 26 days
fledging min.: 50 days fledging max.: 60 days
broods: 1   eggs min.: 7  
      eggs max.: 8  


Oriental Region : China, Southeast Asia. South eastern former USSR (east of Amur River), eastern Mongolia, Korea, southern Sakhalin, Japan, over most of China south to Kwangtung, northern Yunnan, Szechwan


It is a bird of freshwater lakes and marshes in fairly open country and feeds by dabbling for plant food mainly in the evening or at night.


It nests on the ground in vegetation near water, and lays 7-9 eggs whcih are incubated for about 24 days. It nests in single pairs or loose groups, the nest is a pad build of grass and weeds, lined with featehrs and down. The young fledgde after about 6-7 weeks.

Feeding habits

It is a bird of freshwater lakes and marshes in fairly open country and feeds by dabbling for plant food mainly in the evening or at nigh

Video Eastern Spot-billed Duck


copyright: J. del Hoyo


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). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified but is believed to be very large, and hence does not 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.
Eastern Spot-billed Duck status Least Concern


Anas zonorhyncha northern populations migrate to winter southern and eastern China; occasional west in Mongolia and to Lake Baikal, also Taiwan. Small numbers south to Thailand, Cambodia.

Distribution map

Eastern Spot-billed Duck distribution range map

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