Justification of Red List Category
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 is extremely 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.
The global population is estimated to number c.2,800,000-3,300,000 individuals (Wetlands International 2015). The European population is estimated at 469,000-645,000 pairs, which equates to 937,000-1,290,000 mature individuals (BirdLife International 2015).
The overall trend is decreasing, although some populations may be stable or increasing (Wetlands International 2015). The population trend is increasing in North America (based on BBS/CBC data: Butcher and Niven 2007) and the European trend is estimated to be stable (BirdLife International 2015).
Behaviour The species is strongly migratory, undertaking significant cold weather movements of varying magnitude (Scott and Rose 1996). It leaves its breeding grounds in late summer (September) to arrive in its wintering grounds across Europe and Asia in October and November (Scott and Rose 1996, Kear 2005b). Populations leave their winter quarters again between March and April, and arrive in their breeding grounds in northern Russia during the second half of May (Scott and Rose 1996, Kear 2005b). Both the males and females of the species undergo a flightless moult period after breeding and whilst still in their breeding range, during which they congregate at moult gatherings (Scott and Rose 1996, Kear 2005b) (males moult their flight feathers between late May and July, females between late June and early September) (Scott and Rose 1996). Birds of this species are dispersive during the breeding season and nest in pairs or small groups (Brown et al. 1982, Madge and Burn 1988, Kear 2005b). On passage to their wintering grounds individuals come together in large numbers, and during the non-breeding season the species is highly gregarious, forming close aggregations (4,200 birds were recorded in one wintering flock in Ethiopia) (Brown et al. 1982, Madge and Burn 1988). It is chiefly a diurnal feeder (Myrfyn and Thomas 1979), but is sometimes nocturnal (depending on local disturbances and tides, especially in its non-breeding marine habitats) (Kear 2005b). Habitat Breeding This species breeds in lowland freshwater marshes, slow-flowing large rivers (Kretchmar 1994) and shallow lakes and lagoons with ample submerged, floating and emerging vegetation (Kear 2005b). Ideal wetland habitats for this species are those surrounded by sparse open forest, woodland and especially agricultural land (Kretchmar 1994, Kear 2005b), in the boreal and subarctic zone (Cramp and Simmons 1977, Kear 2005b). It avoids tundra, densely forested and mountainous country, as well as fast flowing rivers and streams, but tolerates saline or alkaline steppe lakes and wetlands (Cramp and Simmons 1977, Madge and Burn 1988). Non-breeding In the non-breeding season this species shows a preference for coastal salt-marshes, freshwater, brackish and saline lagoons (Cramp and Simmons 1977), flooded grasslands (Cramp and Simmons 1977), estuaries, intertidal mudflats (Cramp and Simmons 1977), and other sheltered marine habitats (Kear 2005b). Diet It is vegetarian and consumes the leaves, seeds, stems and root bulbs of pond weeds, fine grasses (Myrfyn and Thomas 1979) (especially from agricultural land surrounding lakes) (Jacobsen 1993), horsetails (Kretchmar 1994) and eelgrass, as well as algae (Johnsgard 1978). Animal material is taken rarely and usually incidentally along with vegetation or seeds (Myrfyn and Thomas 1979, Kear 2005b). Breeding site The nests of this species are shallow depressions in the ground lined with vegetation, usually positioned not far from water and well concealed under overhanging vegetation, in grass tussocks, scrub (Kear 2005b), and especially in heather (Jacobsen and Ugelvik 1998).
This species is susceptible to disturbance from freshwater recreational activities (del Hoyo et al. 1992, Grishanov 2006) (e.g. tourists walking) (Mathers et al. 2000), pollution (including thallium contamination [Mochizuki, et al. 2005], petroleum pollution [Grishanov 2006]), wetland drainage (del Hoyo et al. 1992, Grishanov 2006), peat-extraction (e.g. in the Kaliningrad region of Russia) (Grishanov 2006), changing wetland management practices (decreased grazing and mowing in meadows leading to scrub over-growth) (Grishanov 2006) and the burning and mowing of reeds (Grishanov 2006). Avian influenza virus (strain H5N1) is also a potential threat (Melville and Shortridge 2006, Jonassen and Handeland 2007), as is poisoning from the ingestion of lead shot pellets (Mondain-Monval et al. 2002). Utilisation This species is hunted for sport (e.g. in the UK) (del Hoyo et al. 1992, Kear 2005b), and although population numbers in an area decrease significantly after a period of shooting, there is no current evidence that such utilisation poses and immediate threat to the species (Vaananen 2001, Bregnballe et al. 2006). The eggs of this species used to be (and possibly still are) harvested in Iceland (Gudmundsson 1979). This species is also hunted for commercial and recreational purposes in Gilan Province, northern Iran (Balmaki and Barati 2006).
Conservation Actions Underway
CMS Appendix II. EU Birds Directive Annex II and III. The following information refers to the species's European range only: Red Foxes (Vulpes vulpes) and Pine Martens (Martes martes) were removed from regions in Finland resulting in a significant increase in the breeding success of this species (Kauhala 2004).
Conservation Actions Proposed
The following information refers to the species's European range only: Suitable areas of wetland habitat should be protected from changing management practices, disturbance and modification. The impact of hunting should be researched and monitored to ensure bag numbers are sustainable and the use of lead shot banned.
Text account compilers
Butchart, S., Malpas, L., Ekstrom, J., Ashpole, J
BirdLife International (2020) Species factsheet: Mareca penelope. Downloaded from http://www.birdlife.org on 09/04/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 09/04/2020.