![]() rufa breeds in the Canadian low Arctic and winters on the coasts of south Florida, Texas, northern Brazil (15,400 individuals ) and southern South America C. roselaari breeds on Wrangel Island (off north-east Siberia) and north-west Alaska, wintering primarily in western Mexico, as well as the coast of south-east U.S.A., southern Panama and northern Venezuela C. rogersi breeds on the Chukotskiy Peninsula and possibly further west, and winters in Australasia (Van Gils et al. piersmai breeds in the New Siberian Islands (Russia) and winters in north-west Australia C. canutus breeds in central and northern Siberia, the Taymyr Peninsula and possibly Yakutia, wintering in western and southern Africa and south Asia C. It winters on the Atlantic and Pacific coasts of North and South America, north-western Europe, along the west coast of Africa from Tunisia and Morocco down to South Africa, across southern Asia and around Australasia (Van Gils and Wiersma 1996). The species has an extremely large range, breeding from Alaska ( U.S.A.) across the Arctic to Greenland ( Denmark) and northern Russia. Overall the global population is estimated to be decreasing at a rate of c. The study predicts the population will halve within four years. Survival in north-west Australia in late winter was constantly high however survival during periods away from Australia declined in 2011, with an annual survival rate of 0.67 (Piersma et al. ![]() This decrease is supported by a study on adult survival. An analysis of monitoring data from around Australia and New Zealand found that both the piersmai and rogersi populations which use the flyway have experienced strong population declines, estimated at a 57.4% decrease over three generations (Studds et al. Approximately 10-14% of the global population uses the East Asian-Australasian Flyway. Whilst counts in Delaware Bay showed similarly large declines: 70% decrease between 1981-1983 (59,946 individuals) and 2005-2014 (18,387) (USFWS 2014). Between 20 the population at Tierra del Fuego has varied in the range of 10,000-15,000 individuals (R.I.G. The number of birds in Tierra del Fuego declined strongly (75% decrease) between 1985-2000 (52,244 individuals) and 2011-2013 (11,385 individuals) (USFWS 2014). The rufa population has undergone a significant decline in the last decade (Andres et al. The roselaari population trend is uncertain, but is possibly declining (Andres et al. The canutus population decreased strongly in the short- and long-term (14, respectively) (van Roomen et al. (2014) found the population was stable/fluctuating in the short- and long-term. However the European Red List of Birds suggests that the population is increasing strongly in the short-term and experiencing a moderate increase in the long-term (BirdLife International 2015). Trend justification The islandica population trend shows a moderate decrease between 20, whilst the long-term trend is fluctuating (Nagy et al. 2016) and 44,763 individuals (Niles et al. Population justification The global population is estimated to number 891,000-979,000 individuals (Wetlands International 2015). The European population is estimated at 15,000-30,000 pairs, which equates to 30,000-60,000 mature individuals (BirdLife International 2015), and the population overwintering in Australia and the Americas have been estimated at 110,000 individuals (Hansen et al. Should new research resolve uncertainties in the trends of several of these subpopulations the species may warrant uplisting or downlisting. Two subpopulations use the East Asian-Australasian Flyway and have experienced significant declines owing to loss of habitat in the Yellow Sea. The rufa and canutus subpopulations have both experienced population declines. The population trend of the largest subpopulation, islandica, is unclear as is the trend of roselaari. It has an extremely large range and six subpopulations across which trends are variable. ![]() Justification of Red List Category This species is listed as Near Threatened as it almost meets the requirements for listing as threatened under criteria A2abc+3bc+4abc.
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