• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Eastern Spot-billed Duck - BirdForum Opus

Adult male
Photo © by Joseph Morlan
Yokohama Park, Yokohama, Japan, 3 May 2017

Alternate name: Chinese Spot-billed Duck

Anas zonorhyncha

Identification

58-63 cm (22¾-24¾ in)
Slightly larger than Mallard. Male: Body is blackish with brown scaling and black tail coverts. The head is whitish with a black cap, eye-stripe and short gape line. Inner tertials are white at the tip and the bill is black with a yellow tip. Eyes dark brown. Legs bright orange. Shows a blue speculum in flight. Female: Similar to male but tail coverts browner, not black.

Pair
Photo © by Barry Heinrich
Ganseong, Gangwon Province, South Korea, 28 June 2010

Similar Species

Indian Spot-billed Duck have red spots at the base of its bill conspicuous in males. These spots are absent in the Eastern Spot-billed. They also have all white tertials, a green (not blue) speculum and lack the dark gape line. Pacific Black Duck is similar to Eastern Spot-billed but lacks the yellow tip to its bill. Mallard females and eclipse males have a less contrasting face pattern and their bill is either all yellow (males) or orange with gray smudging (females)

Distribution

Widely distributed in Eastern Asia from southeast Siberia, Japan and Korea south to China. Winters in southern China, Taiwan and the Philippines. Vagrant to northeast India.

Taxonomy

A dabbling duck of the genus Anas. Forms a superspecies with Indian Spot-billed Duck, Pacific Black Duck and Philippine Duck. It has been considered conspecific with Indian Spot-billed Duck in the past. However the two breed sympatrically in parts of China confirming they are separate biological species[4]. This is a monotypic species[1].

Photo by Russell Jenkins
Fukushimagata, Niigata, Japan, 25 March 2008

Habitat

Various types of wetlands, at the coast and inland. Prefers shallow water with vegetation.

Behaviour

Actions

Like other dabbling ducks this species feeds by head-dipping and upending in the water, but not diving.

Breeding

Breeding season variable. Usually in single pairs but may form loose small colonies. Nests in a pad of vegetation on the ground or in trees, always near water. The plate-shaped nest is composed of herbs, bamboo, reeds and dead grass. They lay 7-9 creamy-white eggs. Clutch sizes reported of up to 14 eggs may be caused by egg-dumping.

Diet

Feeds vegetarian, mostly seeds, parts of grasses, sedges and aquatic vegetation. Only occasionally water insects are taken.

Movements

Partially migratory with the northernmost populations spending the winter in south and east China.

Vocalisations

Quacking gwet, gwet given by the female is similar to the Mallard but often louder and in descending series.

References

  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2018. The eBird/Clements checklist of birds of the world: v2018. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. del Hoyo, J., Collar, N. & Kirwan, G.M. (2017). Chinese Spot-billed Duck (Anas zonorhyncha). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/467118 on 5 June 2017).
  3. Kulikova, I.V., Zhuravlev, Y.N. & McCracken, K.G. (2004) Asymmetric hybridization and sex-biased gene flow between Eastern Spot-billed Ducks (Anas zonorhyncha) and Mallards (A. platyrhynchos) in the Russian Far East. Auk 121(3): 930–949.
  4. Leader, P.J. (2006) Sympatric breeding of two Spot-billed Duck Anas poecilorhyncha taxa in southern China. Bull. Brit. Orn. Club 126(4): 248–252.

Recommended Citation

External Links

Back
Top