|Scientific Name:||Aythya nyroca (Güldenstädt, 1770)|
|Taxonomic Source(s):||Cramp, S. and Simmons, K.E.L. (eds). 1977-1994. Handbook of the birds of Europe, the Middle East and Africa. The birds of the western Palearctic. Oxford University Press, Oxford.|
|Identification information:||38-42 cm. Dark chestnut coloured diving duck. Both sexes uniform chestnut, slightly darker on back with white belly and undertail; male with distinctive pale iris. Juvenile similar but belly and undertail grey-buff. In flight a broad white wingbar extends onto outer primaries. Similar spp. Easily distinguished from other Aythya ducks by white undertail when sitting and extensive wingbar in flight. Voice In spring female noisy in flight with err, err... call and male with a short chuk call. Hints Prefers shallower and more vegetated areas than other Aythya species and seldom sits out on open water. Outside of main range search flocks of other diving ducks.|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Contributor(s):||Baral, H., Braunlich, A., Brouwer, J., Halder, R., Hatzofe, O., Heinicke, T., Hughes, B., Inskipp, C., Isfendiyaroglu, S., Jayadevan, P., Katzner, T., Khan, A.A., Liu Dongping, .., Mischenko, A.L., Parveen, A., Petkov, N., Sklyarenko, S., Subramanya, S., Tordoff, A.W., Xing Lianlian, .., Yasmeen, R., Yerokhov, S., Dowsett, R.J., Raudonikis, L., Garrido, J., Gadhvi, I., Nayak, A. K., Marchowski, D., Baccetti, N., Bhujabal, M., Singh, R.K.B., Chowdhury, S. & Zockler, C.|
|Facilitator/Compiler(s):||Benstead, P., Capper, D., Derhé, M., Harding, M., Malpas, L., O'Brien, A., Peet, N., Pilgrim, J., Ashpole, J, Symes, A., Martin, R|
Given that this species's range may fluctuate considerably from year to year - particularly in Asia - owing to changing water levels, it is very hard to estimate the global population or trends. There have been rapid declines in Europe, but evidence of declines in the larger Asian populations is sparse and sometimes contradictory. The species is currently listed as Near Threatened as it is suspected to be undergoing a moderately rapid overall decline; evidence of rapid declines in Asia would qualify the species for uplisting to Vulnerable, but conversely evidence of stability could lead to its downlisting to Least Concern.
|Previously published Red List assessments:|
This species breeds principally in south-western Asia (east to China and south to Pakistan and India), central and eastern Europe, and north Africa (Callaghan 1999, Vinicombe 2000). The wintering range overlaps with the breeding range and extends to the Middle East, north-east and West Africa and South-East Asia. The current global population is estimated to fall in the band of c.180,000-240,000 individuals.
Other large winter counts have been made in Azerbaijan (9,000 birds), Turkmenistan (21,000 birds) (Carboneras 1992a) and Uzbekistan (7,000 birds [Kashkarov and Mukhina 1997], but recently less [S. Yerokhov verbally per N. Petkov in litt. 2005]). Small numbers occur on passage in Lebanon and Qatar and also in winter in Iraq, Israel, Jordan, Oman, Saudi Arabia, Syria, United Arab Emirates and Yemen.
The species declined markedly in Europe where there have been declines of more than 20% in nine European countries (BirdLife International 2004, O. Hatzofe in litt. 2005, BirdLife International 2015). Following a large decline in Europe during 1970-1990 (Unpublished expert communications to S. Sklyarenko 2005), the species continued to decline during 1990-2000, when up to 45% of birds appear to have been lost (particularly in south-east Europe). The European population was believed to have declined overall by >30% (BirdLife International 2004, O. Hatzofe in litt. 2005). The most recent assessment of the European population size trend was assessed as unknown (BirdLife International 2015).
Native:Afghanistan; Albania; Algeria; Armenia; Austria; Azerbaijan; Bangladesh; Belarus; Belgium; Benin; Bhutan; Bosnia and Herzegovina; Bulgaria; Central African Republic; Chad; China; Croatia; Cyprus; Czech Republic; Egypt; Eritrea; Ethiopia; France; Gambia; Georgia; Germany; Greece; Hungary; India; Iran, Islamic Republic of; Iraq; Israel; Italy; Jordan; Kazakhstan; Kuwait; Kyrgyzstan; Latvia; Lebanon; Libya; Liechtenstein; Lithuania; Luxembourg; Macedonia, the former Yugoslav Republic of; Mali; Malta; Mauritania; Moldova; Mongolia; Montenegro; Morocco; Myanmar; Nepal; Netherlands; Niger; Nigeria; Oman; Pakistan; Palestinian Territory, Occupied; Poland; Portugal; Qatar; Romania; Russian Federation (Central Asian Russia, Eastern Asian Russia, European Russia); Saudi Arabia; Senegal; Serbia; Slovakia; Slovenia; South Sudan; Sudan; Switzerland; Syrian Arab Republic; Tajikistan; Thailand; Tunisia; Turkey; Turkmenistan; Ukraine; United Arab Emirates; Uzbekistan; Viet Nam; Western Sahara; Yemen
Vagrant:Bahrain; Bermuda; Burkina Faso; Cape Verde; Denmark; Finland; Ghana; Hong Kong; Ireland; Japan; Maldives; Norway; Seychelles; Sierra Leone; Spain; Sweden; Togo; Uganda; United Kingdom
Present - origin uncertain:Cameroon
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The most recent population estimates as collated by Wetlands International are as follows: 5,700-6,300 West Mediterranean/North & West Africa; 50,000-82,000 Eastern Europe/East Mediterranean & Sahelian Africa; 25,000-50,000 Western Asia/South-west Asia & North-east Africa, and 100,000 elsewhere in Asia (Wetlands International 2017a,b; Mundkur et al. 2017), giving a total of 180,700–238,300 individuals.|
Trend Justification: This species's range has fluctuated considerably over the last c.150 years as it has modified its distribution. However, most figures suggest widespread declines (Wetlands International 2016). Owing to significant local declines it was classified as Vulnerable in Europe, however the most recent assessment of the European population listed the trend as unknown and the species's status as Least Concern (BirdLife International 2015). Evidence of declines in the larger Asian populations is sparse, and sometimes contradictory. In the absence of a clearer overall picture, the overall population is precautionarily suspected to be declining at a moderate rate over three generations.
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||Behaviour This species is chiefly migratory (del Hoyo et al. 1992, Scott and Rose 1996), although little is known about its migratory routes (Scott and Rose 1996) and some individuals in southern populations may remain on the breeding grounds all year (Kear 2005b). It breeds from April or May (del Hoyo et al. 1992) until late June (Madge and Burn 1988) in single pairs or loose groups (del Hoyo et al. 1992). Adults undertake a wing moulting period on the breeding grounds between July and August (Robinson and Hughes 2006) when large flocks of moulting individuals may gather (Robinson and Hughes 2006) (no moult migration is recorded however [Scott and Rose 1996]). Departure from the breeding grounds begins in mid- to late-August (N. Petkov in litt. 2008) and peaks in October (Kear 2005b), with the species arriving in wintering areas from late October (Scott and Rose 1996). The return migration to the breeding grounds begins in early March (Scott and Rose 1996). Large gatherings of up to 100 individuals may occur prior to migration at the end of the post-breeding moult (Madge and Burn 1988) (July to August Scott and Rose (1996]), and on migration the species often remains in small groups of 20-50 individuals (N. Petkov in litt. 2008). Outside of the breeding season the species may be observed solitarily, in pairs or small loose groups (Madge and Burn 1988) of 2-5 individuals (Snow and Perrins 1998), and larger gatherings of 1,000-2,000 individuals are also recorded from wintering grounds in Niger and Chad (Petkov et al. 2003). |
Habitat It shows a strong preference for fresh standing water (Snow and Perrins 1998, N. Petkov in litt. 2008) and is very rarely found on flowing streams or rivers (N. Petkov in litt. 2008). It requires shallow water 30-100 cm deep close to littoral vegetation for feeeding (del Hoyo et al. 1992, Kear 2005b) and generally avoids large open areas (Kear 2005b, Scott and Rose 1996). In Bulgaria there is evidence that the species shows a preference for well-vegetated, comparatively shallow wetlands with well-structured mosaic vegetation and a diversity of microhabitats. It is also found on shallow mudflats, possibly as a result of more accessible and abundant invertebrate food sources in this habitat (Petkov in prep.) Breeding Shallow eutrophic freshwater pools and marshes with dense abundant submergent, floating, emergent and shoreline vegetation (e.g. reedbeds) are the major breeding habitats (del Hoyo et al. 1992, Kear 2005b, N. Petkov in litt. 2008). Shallow banks with flooded vegetation and mudflats are particularly used for foraging during this season. The species shows a particular preference for breeding, moulting and staging on large river deltas (Kear (2005b, Scott and Rose 1996, Robinson and Hughes 2006) and extensively managed fish ponds in Eastern Europe (Petkov 2006, Robinson and Hughes 2006). It is also less-commonly known to utilise brackish waters of estuaries, coastal lagoons, reservoirs, salt-pans, sewage farms, canals and drainage ditches during this season (Snow and Perrins 1998, Robinson and Hughes 2006, N. Petkov in litt. 2008). Non-breeding Its habitat requirements outside of the breeding season are similar to those of the breeding season (Kear 2005b), although it may also frequent large lakes, open lagoons, coastal marshes with reedbeds (del Hoyo et al. 1992, Kear 2005b, Scott and Rose 1996) and shallow coastal bays, straits and estuaries (Robinson and Hughes 2006).
Diet Although the species is omnivorous, plant material such as seeds, roots and vegetative parts of aquatic plants (del Hoyo et al. 1992) (Potamogeton spp., Ceratophyllum spp., Scirpus spp., Carex spp. and macroalgae Chara spp. [Kear 2005b]) dominates its diet. Animal matter taken includes worms, molluscs (del Hoyo et al. 1992) (snails [Kear 2005b]), crustaceans, adult and larval insects (del Hoyo et al. 1992) (beetles, chironomids (Kear 2005b), dragonflies, waterbugs, caddisflies, flies [Brown et al. 1982]), amphibians (del Hoyo et al. 1992) (frogs, tadpoles and spawn [Kear 2005b, Brown et al. 1982]) and small fish (del Hoyo et al. 1992) up to 3 cm long (Brown et al. 1982).
Breeding site The nest is a low platform (Snow and Perrins 1998) of reeds and other vegetation (del Hoyo et al. 1992) placed on the ground or on an islet or hummock in thick vegetation close to water (Kear 2005b, Johnsgard 1978). Alternatively nests may be placed over water on floating mats of vegetation (Johnsgard 1978) or in dense reedbeds along the shoreline (Kear 2005b, Johnsgard 1978).
|Systems:||Terrestrial; Freshwater; Marine|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||7.6|
|Movement patterns:||Full Migrant|
|Congregatory:||Congregatory (and dispersive)|
|Major Threat(s):||The species is threatened by the degradation and destruction of well-vegetated shallow pools and other wetland habitats (Vinicombe 2000, del Hoyo et al. 1992, Kear 2005b, Robinson and Hughes 2006) (e.g. changes to the vegetation community, disruption of water regimes, siltation, and increased water turbidity [Robinson and Hughes 2006]) as a result of excessive drainage and water abstraction (Vinicombe 2000, Grishanov 2006, Robinson and Hughes 2006), peat extraction (Grishanov 2006), eutrophication (from inadequate sewage treatment and nutrient run-off [Robinson and Hughes 2006]), oil pollution (Grishanov 2006), dam and barrage construction, the building of infrastructure on flood-plains (Vinicombe 2000, Robinson and Hughes 2006) and river canalisation (Kear 2005b). Changing land management practices such as reed cutting and burning during the breeding season (Petkov 2006), over-grazing (Robinson and Hughes 2006) decreased grazing and mowing of wet meadows (Grishanov 2006), and abandonment (causing succession to scrub) or intensification (causing reversion to open water) of extensively managed fishponds (Vinicombe 2000, Kear 2005b, Petkov 2006, Robinson and Hughes 2006) also threatens the species. The introduction of non-native species has caused further habitat degradation. For example the stocking of lakes with and accidental introduction of Grass Carp Ctenopharyngodon idella has resulted in reductions in macrophyte biomass and corresponding reductions in invertebrate biomass (Kear 2005b, Robinson and Hughes 2006), and in Bulgaria an introduced shrub (Desert False Indigo Amorpha fruticosa) is changing the ecological character of wetlands (Robinson and Hughes 2006). Introduced predators such as the Wels Catfish Silurus glanis (Kazakhstan) that predate ducklings, and the Muskrat Ondatra zibethicus (Aral Sea region) have also caused population declines (Robinson and Hughes 2006). Increased drought due to global climate change may pose a threat to the species in part of its range (Vinicombe 2000, Robinson and Hughes 2006). Disturbance by fishing boats and anglers alongside fringe vegetation could cause abandonment of the breeding sites or disrupt the timing of breeding (N. Petkov in litt. 2008). Hunting is another serious threat to the species (Vinicombe 2000, del Hoyo et al. 1992, Robinson and Hughes 2006). Large numbers are shot on passage in the autumn (e.g. through the Volga delta) and on the wintering grounds (e.g. Sudan) (Kear 2005b, Balmaki and Barati 2006). Illegal and accidental hunting also persists in most European countries. Other lower-level threats include lead poisoning (from ingestion of discarded lead shot), fires in areas of reed thickets, peat bogs and woods (Grishanov 2006) and entanglement and drowning in fishing nets (Robinson and Hughes 2006) and hybridisation with native species (e.g. Tufted Duck Aythya fuligula and Common Pochard Aythya ferina in Switzerland [Leuzinger 2010]).|
Conservation and research actions underway
The species is fully protected in Belarus, Bulgaria, Czech Republic, France, Germany, Hungary, Italy, Moldova, Netherlands, Russia, Slovakia, Slovenia, Spain and Switzerland, and is protected from hunting in Austria, Belgium, Greece, Poland, Turkey and Ukraine. It is listed on Annex I of the European Union Directive on the Conservation of Wild Birds, on Appendix III of the Bern Convention and on Appendices I and II of the Bonn Convention. The species has received little international conservation action, although a number of national initiatives have been developed recently, notably habitat management in Bulgaria and re-introduction schemes in Italy (Berezovikov and Samusev 1998). One of the highest priorities for this species is to establish systematic annual monitoring of Asian populations to more accurately assess trends. Such monitoring, if it provided evidence of continuing and significant declines across major Asian populations, could provide reason to uplist this species. An International Single Species Action Plan has been adopted by the Bern Convention, CMS and AEWA, which lays out a framework for conservation action throughout the specie's range (Robinson and Callaghan 2003). A restoration project for two key breeding sites on the Danube in Bulgaria is underway, funded by the World Bank (N. Petkov in litt. 2003). Conservation and research actions proposed
Promote the full legal protection of the species and its habitat through national and international legislation, promote environmentally friendly management of fishponds in Eastern Europe, promote adequate protection and management of key sites, promote conservation in the wider environment for the benefit of the species and its habitat, prevent mortality and disturbance caused by hunting, monitor the remaining population (particularly in Asia) and develop census techniques, investigate productivity and mortality, investigate ecology and limiting factors, investigate the impact of C. idella on the species and its habitat; develop and implement education programmes for the conservation of the species and its habitats.
|Citation:||BirdLife International. 2017. Aythya nyroca. The IUCN Red List of Threatened Species 2017: e.T22680373A119399096.Downloaded on 19 August 2018.|
|Feedback:||If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided|