Baer's Pochard

Baer's pochard is a diving duck of eastern Asia. Breeding males have a black head and neck with a green gloss, though in poor light the bird can look entirely black. It is closely related to the ferruginous duck and was once treated as the same species, but it is larger, with a longer, more rounded head and white flanks visible on the water. It nests among reeds and sedges in shallow water or on small islands, laying 5 to 14 eggs. The species was once common but is now very rare, with fewer than 1,000 mature individuals possibly remaining.

About the Baer's pochard

Baer's pochard is a small diving duck from eastern Asia, listed as Critically Endangered. It belongs to Aythya, the genus of pochards and scaups that also includes the redhead, and it is closely related to the ferruginous duck. It now breeds mainly in China and once wintered across South and Southeast Asia.

Its scientific name is Aythya baeri. Both that name and the English one honor the Baltic German naturalist Karl Ernst von Baer. It has a string of other names, including eastern white-eye, Siberian white-eye and green-headed pochard. Gustav Radde first described it in 1863 from a small flock collected along the middle Amur River during the breeding season.

The breeding male is handsome in a subtle way. His head and neck are black with a green gloss, though in poor light the bird can look entirely black. He has white or pale yellow eyes, a blackish-brown back, a dark chestnut breast and white or light chestnut flanks. The female has brown eyes and a dark brown head and neck that blend into a chestnut-brown breast and flanks, plus a bright chestnut spot in front of the eye. Both sexes show a broad white wing stripe, white under the tail and a dark gray bill with a black nail at the tip.

It is a compact duck, 41–47 cm (16–19 in) long with a wingspan of 70–79 cm (28–31 in). Males are slightly larger on average, weighing 500–730 g (18–26 oz). It is usually quiet, but in courtship both sexes give a harsh "graaaak."

Behavior and diet

Baer's pochard is shy. It lives on open, slow-flowing lakes, swamps and ponds, and in winter it gathers in large flocks with other pochards on big freshwater lakes and reservoirs. It is a strong flier, a good diver and swimmer, and can take off from the water quickly when disturbed. On migration, small groups of ten to a few dozen birds fly low in wedge-shaped formations.

Its feeding habits are poorly known. In winter the birds sleep through the day, leave at dusk with other ducks for feeding sites nobody has yet pinned down, and return before dawn. The known diet includes aquatic plants, grass seeds and mollusks.

Pairs appear to be monogamous, at least within a season. In courtship, the male swims around the female, repeatedly nodding his head, and chases off other males without serious fights. The female nods back, and the pair then leaves the flock to nest.

The nest is a cylinder of sedges, reeds and other plants lined with down, built among emergent vegetation in shallow water or on small islands and ridges. Clutches range from 5 to 14 eggs. The female incubates for 23–26 days while the male stands guard about 10 m (33 ft) away. She leaves the nest two or three times a day to feed, covering the eggs first, and raises the nest if water levels climb. On the hottest days she stands over the eggs to shade them and even carries water in her feathers to cool them.

Nesting success is low. Only about 14–45 percent of nests survive, undone by desertion, flooding and predators, mainly Siberian weasels. In Wuhan, where many birds now breed on crayfish farms, farm work and egg collecting add to the losses.

Range and habitat

Baer's pochard traditionally bred in the Amur and Ussuri river basins of northeast China and the southeastern Russian Far East. It wintered south of the Yellow River in China and across Taiwan, Japan, Bangladesh, India, North Korea, Laos, Myanmar, Nepal, Thailand and Vietnam.

That map has shrunk dramatically. Since 2010 there have been no confirmed breeding records anywhere north of Beijing. Since 2012, though, new breeding sites have been found farther south in China, in Hebei, Hubei and Jiangxi provinces. There the warmer climate gives a breeding season about twice as long, letting females lay a second clutch if the first fails, and the birds no longer migrate. In winter, the species has been absent from everywhere outside mainland China, apart from vagrants, since at least 2010–2011.

It breeds around lakes with rich aquatic vegetation, nesting in dense grass and flooded tussock or shrubby meadows.

Baer's pochard vs ferruginous duck

The two species were once considered one, and they look alike, especially males with their white eyes and white under the tail. The ferruginous duck has even been seen displaying to Baer's pochards in the wild.

Conservation status

Baer's pochard is listed as Critically Endangered on the IUCN Red List. Once common, it is now very rare, with perhaps fewer than 1,000 mature birds left, and the decline shows no sign of slowing. It was moved from Vulnerable to Endangered in 2008 and to Critically Endangered in 2012.

The counts tell the story. Chinese wintering records fell from 16,792 birds over 1986–1993 to 2,131 over 2002–2011, and the wintering population in mainland China has dropped by more than 99 percent. Outside China, counts fell from hundreds or thousands per country in the 1990s to just 48 birds across all other wintering grounds in 2005–2011.

Hunting and habitat loss are the main threats. At one Chinese site, between 336 and 4,803 pochards were hunted every year from 1981 to 1997, and pollution, fishery management and changes in the Yangtze floodplain wetlands have degraded wintering grounds. Most breeding sites and suitable habitat lie outside protected areas, often near big cities. Hybridization with expanding common and ferruginous pochards may also be happening.

Action has stepped up. A Baer's Pochard Task Force under the East Asian–Australasian Flyway Partnership was endorsed in 2015, China made it a first-class protected animal by 2021, and in 2022 a captive population of 54 birds was established in China, with plans to expand it for reintroduction.