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 very 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. However, evidence of declines and hunting pressure in some parts of its range necessitate close monitoring of its population.
Morrison et al. (2006) give a population estimate of 400,000 birds, with a range of 300,000–500,000. This estimate is assumed here to equate to c.270,000 mature individuals.
Data from the Breeding Bird Survey (BBS) suggest that the species has undergone a large and statistically significant decrease in North America over the last 40 years (-94.9% decline over 40 years, equating to a -52.6% decline per decade; Butcher and Niven 2007); however, these surveys cover much less than 50% of the species’s range in North America thus may not provide data that are representative of the overall population (G. Donaldson in litt. 2012).
Following reported declines in the wintering population of T. flavipes in Suriname since the 1970s, surveys were carried out at one site in 2008-2009 using the methods of a previous survey at the same location (Ottema and Ramcharan 2009). The results showed that numbers of T. flavipes were down by c.80% on those recorded in 2002-2003. This change is assumed by Ottema and Ramcharan (2009) to be representative of the entire coast of Suriname, based on an aerial survey of the coast in December 2008, additional ground-based observations and four surveys at another location. Ottema and Ramcharan (2009) suggest that the global population may have declined by c.75% from 2002-2003 to 2008-2009, and that the species may face extinction within 20-30 years, citing Morrison and Ross’s (1989) observations from the mid-1980s that more than 70% of T. flavipes and Greater Yellowlegs T. melanoleuca wintering on the South American coast do so in Suriname. The current estimate for the combined wintering populations of T. flavipes and T. melanoleuca along the coast of north-eastern South America is 8,000, based on multiple aerial surveys (Suriname: 2008, 2011, 2014; French Guiana: 2008, 2014; Brazil: 2011, 2014), suggesting a c.90% decline since 2002-2003 (D. Mizrahi in litt. 2014). Populations in Suriname appear to have experienced the most dramatic change, with declines exceeding 96%, while populations in French Guiana (c.5,000-6,000 individuals) generally appear stable (D. Mizrahi in litt. 2014). However, on present evidence it cannot be discounted that the population is shifting its geographical preferences during the non-breeding season, either along the coast of north-eastern South America or more widely.
Declines have also been noted on St Martin since 2000-2001, with 348 counted in January 2001 and fewer than 5 birds counted each year in 2006-2011 (A. Brown in litt. 2011), and at wetlands around Bogota, Colombia, where more than 98% of habitat has been lost (O. Cortes in litt. 2012). Furthermore, a significant downward trend has been noted since 1991 in the population of this species wintering at the Salinas lagoons in south-western Ecuador (B. Haase in litt. 2011 in Clay et al. 2012). In contrast, there are no signs of a significant decline on the coast of Peru (F. Angulo in litt. 2014).
The species is known to be hunted in some parts of the Caribbean and South American coast and is the most hunted shorebird species on Guadeloupe and Martinique, where several thousand are reported to be shot each year (A. Levesque in litt. 2012). Such evidence suggests that hunting pressure is not sustainable in some years (B. Andres in litt. 2012), and studies are planned and being carried out to quantify the impact of hunting and the rate of population decline (B. Andres in litt. 2012, 2014; A. Levesque in litt. 2012). Other threats to the species include habitat loss through logging, agricultural expansion and intensification, urban development and mining, the use of agrochemicals and climate change (Clay et al. 2012).
Until further evidence is available, this species's population is suspected to be undergoing a moderate decline.
Text account compilers
Butchart, S., Ekstrom, J., Symes, A. & Taylor, J.
Andres, B., Angulo Pratolongo, F., Brown, A., Cheskey, T., Cortes, O., Donaldson, G., Levesque, A., Mizrahi, D. & Ruiz, C.
BirdLife International (2018) Species factsheet: Tringa flavipes. Downloaded from http://www.birdlife.org on 16/07/2018. Recommended citation for factsheets for more than one species: BirdLife International (2018) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/07/2018.