NT
Black-tailed Godwit Limosa limosa



Justification

Justification of Red List Category
Although this species is widespread and has a large global population, its numbers have declined rapidly in parts of its range owing to changes in agricultural practices. Overall, the global population is estimated to be declining at such a rate that the species qualifies as Near Threatened.

Population justification
The global population is estimated at 614,000-809,000 individuals (Wetlands International 2016). The population is estimated to number 102,000-149,000 pairs in Europe (including 25,000 pairs in Iceland) (BirdLife International 2015); 25,000-100,000 in west-central Asia; 150,000 in central Asia and Siberia (Asian Waterbird Census unpublished data); 160,000 in the rest of Asia and Australia.

Trend justification
There is still some degree of uncertainty about the size and trend of some of the sub-populations. Nevertheless, the available information suggests that the global population has probably declined by between 14% and 33% at a mean rate of approximately 23% over the 25 years leading up to 2015. This estimate is derived from a series of calculations based on best-worse case scenarios using population estimates from Wetlands International (2017), and trend data from the African-Eurasian Waterbird Census, Asian Waterbird Census, Wetlands International, Pan-European Common Bird Monitoring Scheme and forum contributors. Thus the species's trend is currently best placed in the 20-29% band. In Europe, the population size is estimated to be decreasing by 30-49% in 25.8 years (three generations) (BirdLife International 2015).

Distribution and population

This species has a large discontinuous breeding range extending from Iceland to the Russian far east, with wintering populations in Europe, Africa, the Middle East and Australasia (Van Gils et al. 2017). It occurs as three subspecies, L. l. islandica, L. l. limosa, and L. l. melanuroides. Subspecies islandica breeds predominantly in Iceland, with much smaller numbers in the Faeroe Islands, Shetland (United Kingdom) and the Lofoten Islands (Norway). This subspecies winters in roughly similar numbers in the Republic of Ireland, the United Kingdom, France, Spain and Portugal, with small numbers in the Netherlands (J. Gill in litt. 2016). Subspecies limosa breeds across a wide area extending from Western Europe and central Europe to central Asia and Asiatic Russia, as far east as the River Yenisey. The west European population of this subspecies migrates south through France and Iberia to winter largely in West Africa, while eastern breeding birds winter in southeast Europe to the Middle East, and may also be the origin of wintering birds in Mali, Chad and northern Cameroon (Gill et al. 2007, Oomen 2008, Lourenço & Piersma 2008b). Subspecies melanuroides breeds in disjunct populations in Mongolia, northern China, Siberia (Russia) and the Russian Far East. These birds migrates across a broad front to winter from western South Asia to Australia, encompassing India, Indochina, Taiwan, the Philippines, Indonesia, and Melanesia (Dutson 2011, Van Gils et al. 2017). The global population is estimated at 614,000-809,000 individuals (Wetlands International 2016). 
Population trends vary across the range. There have been large and well-documented declines in the mainland European breeding population (of the nominate subspecies) of between 50-60% (BirdLife International 2015). For example, in the Netherlands the population decreased dramatically from 120,000-135,000 pairs in 1969 and 85,000-100,000 pairs in 1989-1991, to just 46,000-62,000 in 2009 (Tucker and Heath 1994,  BirdLife International 2004a, EU Technical Report 19 2007, Oomen 2008, Höglund et al. 2009), 35,200-59,800 pairs in 2008-2011 (BirdLife International 2015), and potentially to 33,000 pairs in 2015 (Kentie et al. 2016). In certain areas though, the breeding population has recently stabilised as a result of agri-environmental measures (Oosterveld et al. 2016). These declines are mirrored in the information from West African wintering areas, with notable declines in Senegal and Morocco, while further east (Mali, Chad and north Cameroon) wintering numbers appear stable, though data is sparser (Lourenço and Piersma 2008b). This is true also for the central Asian breeding population, which is thought to be stable of fluctuating (L. Belyalova in litt. 2005), but for which there is little recent data. In the eastern flyway, declines have been estimated at between 20-30% over three generations on the species Australian wintering grounds (Garnett et al. 2010), which hold c. 50% of the wintering population of L. l. melanuroides (Watkins 1993). The population of L. l. ilsandica, in contrast, has be increasing dramatically over the past few decades, although this increase may be levelling out and the subpopulation represents a relatively small part of the global population (Gill et al. 2007, Wetlands International in press). A recent analysis based on published literature, survey data and expert opinions from throughout the species range suggests that, overall, the global population may have declined at a mean rate of approximately 23% over 25 years leading up to 2015 (I. Burfield in litt. 2017).

Ecology

Behaviour This species is highly gregarious and migrates on a broad front, making long-distance flights often overland between relatively few staging and wintering areas (del Hoyo et al. 1996). It breeds from April to mid-June in loose, semi-colonial groups of up to 3 pairs per ha (Gunnarsson et al. 2006). Non-breeding birds remain in flocks, often near to the breeding colonies. As soon as the young fledge, breeding birds begin to congregate in loose flocks which can be many thousands strong (Cramp et al. 1983, J. Gill in litt. 2016). The species migrates southwards between late-June and October. During the autumn migration it may roost in flocks of tens of thousands at favoured sites (del Hoyo et al. 1996), and this is the main moulting period for adult birds. The islandica subspecies moults in northwest Europe, while western populations of the nominate subspecies often moult in north Morrocco (J. Gill in litt. 2016), and many adults pause in north Morocco in July to moult. Huge flocks occur at some wintering sites, particularly in the floodplains of Lake Chad. The return passage occurs between February and April (del Hoyo et al. 1996), and birds arrive at the breeding grounds in groups of 5-30 individuals (Johnsgard 1981). Many one-year-old birds remain in the wintering range during the summer. During the winter and migration the species usually forages gregariously (del Hoyo et al. 1996). 
Habitat Breeding In its breeding range it mostly inhabits areas with high but not dense grass and soft soil (del Hoyo et al. 1996, Johnsgard 1981, Schekkerman and Beintema 2007, Tomkovich and Lebedeva 1998), occasionally using sandy areas; although other information suggests it may prefer short vegetation (Laursen and Hald 2012). Its preferred habitats include cattle pastures, hayfields (Johnsgard 1981), lowland wet grasslands, grassy marshland, raised bogs and moorland, lake margins and damp grassy depressions in steppes (del Hoyo et al. 1996). Subspecies islandica shows a distinct preference for large patches of dwarf-birch bog and marsh, particularly with abundant sedge-pools (del Hoyo et al. 1996, Gunnarsson et al. 2006). Extensive farmland habitats are of critical importance for breeding Western European populations (del Hoyo et al. 1996), with young, that grow up in herb-rich meadows recruiting to the breeding population 2.5 times better than young that grow up in monocultures (Kentie et al. 2013). In intensively managed grasslands small shallow pools attract breeding godwits and, in combination with herb rich meadows, may improve breeding succes (Weterings et al. 2015). After the young have fledged, adults and fledglings often move to secondary habitat which more closely resembles that of their non-breeding range, including wet damp areas around fish-ponds and sewage farms, tidal marshes, mud flats and salt-water lagoons (Cramp et al. 1983, Tucker and Heath 1994). Non-breeding Subspecies limosa tends to winter in freshwater habitats, including swampy lake shores, pools, flooded grassland and irrigated rice fields. Subspecies islandica and melanuroides, however, often winter in saline habitats (del Hoyo et al. 1996) such as sheltered estuaries and lagoons with large intertidal mudflats (Johnsgard 1981), sandy beaches, salt-marshes and salt-flats (del Hoyo et al. 1996). Despite these general differences there is considerable overlap in wintering habitat between sympatric populations of subspecies limosa and islandica (Alves et al. 2010, Lopes et al. 2013).  Seasonally-flooded grassland is a critical habitat for the birds wintering in Ireland (Hayhow 2008). Birds on passage in Iberia make much use of rice fields (Lourenço et al. 2010). 
Diet Its diet consists of adult and larval insects (especially beetles), annelid and polychaete worms, molluscs, ragworms, crustaceans, spiders, fish eggs, and the spawn and tadpoles of frogs (Johnsgard 1981, del Hoyo et al. 1996). On the breeding grounds grasshoppers and other orthopterans are often prevalent in the diet (Johnsgard 1981). Particularly during the winter and on migration it will also take plant material including berries, seeds and rice grains (Cramp et al. 1983, Lourenço et al. 2010). On its wintering grounds in Portugal, the bivalve Scrobicularia plana has been found to represent its primary food source (Moreira 1994), while in the salinas of Spain, it mainly feeds on chironomid larvae (Estrella and Masero 2010). Breeding site The nest is placed on the ground in short, often luxurious vegetation (Johnsgard 1981, Cramp et al. 1983, del Hoyo et al. 1996). It consists of a shallow scrape 12-15cm in diameter, lined with a thick mat of stem grass, leaves and other available vegetation (Cramp et al. 1983). Breeding birds show a high degree of nest site fidelity (del Hoyo et al. 1996) and some degree of natal philopatry (Kruk et al. 1998) which is more pronounced among males (Gunnarsson et al. 2011).

Threats

Loss of nesting habitat owing to wetland drainage and agricultural intensification, and conversely abandonment in some parts of the range, are the most significant threats (Mischenko 2008, Kentie et al. 2013). Detrimental activities include the conversion of wet meadows to arable land and loss of habitat to development (Tucker and Heath 1994), increased fertilisation and drainage of grassland (Roodbergen and Teunissen 2014), earlier and more frequent cutting as farmers adapt to climate change (Kleijn et al. 2010), spring burning and scrub encroachment (A. Mischenko in litt. 2007) and possibly disturbance by walkers (Holm and Laursen 2009). Increasing populations of predators to possibly unnatural levels is a significant cause of egg and chick mortality in the Netherlands, exacerbated by intensive farming reducing available cover for the species (Schekkerman et al. 2009, Kentie et al. 2015). On intensively grazed pastures, trampling is a major cause of nest loss, and a switch to monoculture on arable land reduces the supply of insects on which the species feeds (Kentie et al. 2013). In some areas, grassland turnover from 'natural, flower-rich, diverse and wet' to silage monoculture leads to a loss of nests with eggs and chicks due to mowing and starvation of chicks due to a lack of food (Schekkerman and Beintema 2007). A study in the central regions of European Russia suggests that significant decline in spring flood levels during two last decades, as a result climate change, has strengthened the negative impact of agricultural abandonment (A. Mischenko in litt. 2016). 
Habitat fragmentation may cause problems for this species, which nests in dispersed colonies and sub-colonies as protection against predators hence productivity may be low in such areas. Indeed, sink locations have been documented for the species, where birds recruited from good quality habitat disperse to low quality habitats (often suffering high predation) effectively losing these individuals to the population. This has repercussions for the effectiveness of agri-environment measures (Kentie et al. 2015, Leigh et al. 2016). There is a marked decrease in the density of breeding birds near to roads, particularly those with heavy traffic (van der Zande et al. 1980, Reijnen et al. 1996). Natal philopatry means that a decrease in local recruitment could prove catastrophic for individual breeding sites (Kruk et al. 1998). The Icelandic population is potentially at risk from the policy of the Icelandic government to encourage afforestion of the lowland habitats where they breed and from ongoing agricultural expansion (Gunnarsson et al. 2006, Gill et al. 2007), although this population has been increasing strongly over recent decades (BirdLife International 2015).
Threats on migration include pollution, human disturbance, habitat reclamation for tidal energy plants, aquaculture ponds, land conversion for agriculture, urban expansion and agricultural intensification at rice paddies. The proposed development of a new airport near Lisbon is likely to have negative implications on an important site for migratory birds (Gill et al. 2007, Masero et al. 2011). Hunting has been another significant threat, although France has now followed the rest of the European Union (EU) in implementing a five-year ban on hunting of the species, beginning in 2008 (I. Burfield in litt. 2008), which was extended in 2013 for a further five years. Outside the EU, for example on the African wintering grounds, hunting is known to occur but its scale and impact is unknown. Water pollution is probably an issue in parts of the species range (H. Hötker in litt. 2005), although the effects of the release of some pollutants, like untreated sewage, on this species may be minor as long as there are several alternative prey present at a site (Alves et al. 2012). In Egypt there are plans to increase the depth of the sailing channel of the Nile, impacting upon this species's habitat there (H. Ibrahim in litt. 2016). Drought in the West African wintering quarters may have had negative impacts on the mainland European population (Tucker and Heath 1994) in conjunction with the extensive drainage of wetlands in this area, for energy production, water storage and agriculture (Gill et al. 2007). Invasive plants may also degrade wintering habitat in Australia (Garnett et al. 2011). Studies of islandica godwits have shown that individuals breeding in the habitats where productivity is higher also winter in the areas where survival is higher (Gunnarsson et al. 2005), therefore maintaining high quality wintering sites is crucial to raising productivity on breeding grounds. 

Conservation actions

Conservation Actions Underway
EU Birds Directive Annex II. An EU management plan for 2007-2009 was adopted, and an AEWA action plan replaced it at the end of 2008 (Anon. 2008). Intensive management of breeding habitat has been carried out in some Western European countries (H. Hötker in litt. 2005), and a number of agri-environment schemes focus on this species, although results have been mixed (Musters et al. 2001, S. Nagy in litt. 2005, A. Mischenko in litt. 2007, Verhulst et al. 2007). A number of significant wintering areas are protected areas, as are several breeding sites in the UK and the Netherlands. 

Conservation Actions Proposed
Obtain more quantitative data on status, population trends and conservation requirements outside Europe. Carry out research on survival, recruitment, breeding and migration (Gill et al. 2007). Critically evaluate the effectiveness of current conservation action. In the EU, use a mixture of agri-environment schemes, direct payments to wader-friendly farmers (Musters et al. 2001) and large reserves to secure protection and appropriate management of breeding habitat. The coverage of agri-environment schemes in Europe should be increased (Kleijn et al. 2010) and increases in groundwater depth should be prioritised as an outcome (Verhulst et al. 2007). New nature reserves should be established on important sites throughout the species range, and there should be attempts to get greater coverage of key areas for this species within in the Special Protection Areas network (van der Vliet et al. 2015). Manage existing reserves appropriately: prescriptions include avoiding drainage of existing wet meadows, raising water tables where necessary, low-level use of organic fertiliser, low intensity grazing, late mowing, and prevention of succession to bushy vegetation. Winter flooding is sometimes recommended but may reduce numbers of invertebrate prey (Gunnarsson et al. 2005). On intensively farmed land, maintenance of unfertilised field margins has been shown to have positive effects (Oosterveld et al. 2009). Investigate the potential for using a 'headstarting' approach to increase survival to fledging (J. Gill in litt. 2016). Prevent afforestation of lowland breeding habitat in Iceland. Prevent a loss of key breeding areas due to abandonment of grasslands and meadows in east Europe and Russian Far East. Monitor human disturbance as a threat. 
Ensure that migratory staging posts and winter feeding habitats and roosts are conserved and monitored, and knowledge of them is improved (Estrella and Masero 2010). Designate a special protection area at Extremadura's rice fields, which is a key stopover site (Masero et al. 2011). Manage artificial habitats appropriately, e.g. maintain low water levels in salinas such that they are available to foraging godwits (Estrella and Masero 2010), and block drainage to retain water in Iberian rice fields (Lourenço and Piersma 2008a). Protect important Yellow Sea tidal flats in China and South Korea. Engage with governments and local people throughout its migration routes. Effectively enforce the EU-wide ban on hunting until there is clear evidence that the population has returned to a favourable conservation status. Safeguard habitats in West Africa and Iberia, perhaps by offering support to rice producers (Gill et al. 2007). Collaborate with farmers and hunters, carrying out environmental education and outreach work where appropriate. Restore wetland sites in Australia (Garnett et al. 2011). Ensure recognition as a protected animal throughout range (Hancock 2008).

Identification

40-44cm. Large rather graceful wader, with long bill on a relatively small head, long neck and long legs. Colour of fore-body is dull pink-chestnut in summer, paler grey-brown in winter. In flight has a striking white wing-bar and rump. Similar spp. Unmistakeable in flight but sometimes difficult to separate from L. lapponica when on ground at distance. Told from the latter by its distinctive bill structure and much leggier and more erect appearance. Voice High-pitched, nasal, rather strident calls given during breeding season, most common of which is a weeka-weeka-weeka. Characteristic call of birds in flocks is a softer kip kip... or chut chut...

Acknowledgements

Text account compilers
Mahood, S., Butchart, S., Temple, H., Ekstrom, J., Khwaja, N., Martin, R, Malpas, L., Westrip, J., Ashpole, J

Contributors
Nagy, S., Hötker, H., Krüse, H., Mischenko, A., Gill, J., Oosterveld, E., van Dijk, A., Belyalova, L., Garnett, S., Ibrahim, H., Dowsett, R.J., Burfield, I.


Recommended citation
BirdLife International (2017) Species factsheet: Limosa limosa. Downloaded from http://www.birdlife.org on 22/10/2017. Recommended citation for factsheets for more than one species: BirdLife International (2017) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/10/2017.