The Baer's pochard is a diving duck found in eastern Asia. It breeds in southeast Russia and northeast China, migrating in winter to southern China, Vietnam, Japan, and India. Baer's pochard breeds around lakes with rich aquatic vegetation, nesting in dense grass, flooded tussock meadows, or flooded shrubby meadows. In Liaoning, China, it is normally found in densely vegetated coastal wetlands, or around lakes and ponds surrounded by forest. In winter, it occurs on freshwater lakes and reservoirs.
This species has been uplisted to Critically Endangered (IUCN, 2012) owing to an apparent acceleration in the rate of its decline, as measured by numbers on both the breeding and wintering grounds. It is now absent or occurs in extremely reduced numbers over the majority of its former breeding and wintering grounds and is common nowhere. It is thought that hunting and wetland destruction are the key reasons for its decline.
W. Xin, C. Lei, L. Jinyu and T. Fox in litt. (2012) stated that 'we fear that the global population is now less than 1,000 individuals and could be very much lower than this', and so it is placed in the band 250-999 individuals, equating to 167-666 mature individuals, rounded here to 150-700 mature individuals.
It breeds around lakes with rich aquatic vegetation in dense grass or flooded tussock/shrubby meadows. In Liaoning, China, it is usually found in coastal wetlands with dense vegetation, or on rivers and ponds surrounded by forest. The nest is built on a tussock or under shrubs, sometimes floating, and occasionally amongst branches. In winter, it occurs on freshwater lakes and reservoirs.
Threats are poorly understood, but hunting and wetland destruction in its breeding, wintering and staging grounds are probably the reasons for its decline. In several cases, the loss of populations from former important areas have been preceded by low water levels or complete drying up of water bodies (e.g. the loss of the breeding population at Xianghai Reserve and the wintering population at Baiquan wetlands in Wuhan [J. Hornskov in litt. 2005, S. Chowdhury in litt. 2010, W. Xin, C. Lei, L. Jinyu and T. Fox in litt.2012]). There are unconfirmed reports of high mortality from hunting, including a report of 3,000 individuals being shot annually at Rudong, Jiangsu Province (Lei Gang 2010); however, this is very likely an overestimate and may be due to the translation of the species name (Baer’s Pochard is synonymous with Mallard in Chinese) (S. Chan in litt.2011).
Conservation Actions Underway
CMS Appendix II. It is legally protected in Russia, Mongolia and Hong Kong (China) and in some provinces in China. Some of its breeding and wintering sites are within protected areas, including Daursky, Khanka lake and Bolon lake (Russia), Sanjiang and Xianghai (China), Mai Po (Hong Kong), Koshi Barrage (Nepal), and Thale Noi (Thailand).
Conservation Actions Proposed
Research its population, distribution, ecology and threats in order to produce conservation recommendations. Research the species's breeding distribution and biology and feeding biology. Establish more protected areas in its breeding grounds. Extend the area of the Khanka Lake Reserve (Russia). Designate the Xianghai Nature Reserve (China) as a restricted area during the breeding season. Regulate hunting of all Anatidae species in China. Ensure legal protection of this species in all range states.
Captive conservation breeding
Over 300 birds are being managed and monitored in zoos worldwide (ZIMS, 2019) and studbooks are planned (EAZA + AZA), given the probability that captive breeding may be required in the species’ future conservation. Baer's pochards are regularly kept and bred in private collections too (USA and Europe), but exact numbers are unknown.
A genetic analysis was undertaken of captive birds held by the Wildfowl and Wetlands Trust (WWT), in collaboration with Cardiff University and funded by the Oriental Bird Club. About 70 have been genetically sampled in 2015. The results indicated that Baer’s pochard and ferruginous duck are almost indistinguishable, at least in terms of the microsatellites analysed, and are thus genetically very closely related. There was no evidence of hybridisation or significant inbreeding in the WWT captive stock, though there is less genetic diversity in these birds when compared to wild Baer’s pochard, indicating that genetic drift has occurred. Nevertheless, the WWT stock has been well-managed, especially considering the small number of founders and many generations in captivity, and provides a suitable source of founders for a conservation breeding programme.
28 янв 2023
