Data Zone
Justification of Red List category
This species has a small population which is believed to be undergoing a continuing decline, owing to low breeding productivity, predation pressures and loss and degradation of its wetland habitats. In addition, its subpopulation structure is such that the largest subpopulation comprises less than 1,000 mature individuals. It is therefore listed as Vulnerable.
Population justification
Surveys confirmed the presence of 15 breeding sites across Madagascar, including Tsimanampesotse National Park, where 60-100 pairs bred at each year between 2005 and 2007 (S. Zefania, T. Szekely and P. Long in litt. 2007), and 24 nests in Marambitsy Bay between 2002-2005 (Zefania et al. 2008), although no birds were recorded at this site in 2022 (R. Rabarisoa in litt. 2023). Data collected between 2009 and 2023 have shown an average of 50-100 pairs per year at Andavadoaka (S. Zefania in litt. 2023). Individuals have also been recorded in the Tsiribihina estuary and in the mudflats at Bemoramba in Maintiramo (ZICOMA 1998). More recently, between 2006 and 2017, the population in the Mahavavy Delta decreased from 74 to 64 individuals, and from 281 to 28 individuals in the Mangoky River estuary between 2009 and 2020 (Rabarisoa in litt. 2023).
The species' total population was estimated to number 750-6,000 individuals (F. Hawkins in litt. to Wetlands International 2002), however this was not based on systematic surveys (T. Dodman in litt. 2006). The population was then estimated at 3,100 ± 396 (SE) individuals (Long et al. 2008) through the modelling of observed densities at suitable sites across an estimate of the total area of habitat above a defined suitability threshold (Zefania et al. 2005, Long et al. 2006). The standard error range is rounded to the nearest 100 and used as the population range estimate: 2,700-3,500 individuals, roughly equivalent to 1,800-2,300 mature individuals. However, as the species has been experiencing an ongoing decline, the population is now likely to be lower than the estimate made in 2007.
Trend justification
In Andavadoaka, this species exhibits low productivity and inflexible breeding behaviour (S. Zefania et al. in litt. 2007), with reduced breeding success being due to high levels of predation, which could be driving local declines (S. Zefania in litt. 2023). It is suspected that these threats could cause overall declines in the species' population in the future, which may already be declining (S. Zefania in litt. 2023), however, more fieldwork in needed to confirm these suspicions. In other sites, such as the Mahavavy Delta, Marambitsy Bay and the Mangoky River estuary, regular species counts are demonstrating a decline in the population size (R. Rabarisoa in litt. 2023): in the Mahavavy Delta, the population decreased from 74 to 64 individuals between 2006 and 2017; in the Mangoky River estuary the population declined from from 281 to 28 individuals between 2009 and 2020 (R. Rabarisoa in litt. 2023), and 24 nests were counted in Marambitsy Bay between 2002-2005 (Zefania et al. 2008), and 64 individuals were recorded in 2021, but no birds were recorded at this site in 2022 (R. Rabarisoa in litt. 2023). There is no data suggesting compensatory increases in population elsewhere (which could otherwise indicate movement of the species to other sites), although there is insufficient data to quantify the rate of decline. The species is therefore considered to be experiencing a continuing decline.
Charadrius thoracicus occurs somewhat uncommonly between the Mahavavy Delta on the north-west coast (R. Rabarisoa in litt. 2023) and Tapera of Tolagnaro in south-eastern Madagascar (Goodman et al. 1997), including Tsimanampesotse National Park (S. Zefania, T. Szekely and P. Long in litt. 2007). It occurs in many coastal sites, including the Tambohorano wetlands, salt lagoons around Morombe and the Tsiribihina estuary (ZICOMA 1998) or Andavadoaka (S. Zefania in litt. 2023), and also inland such as around around Lake Tsimanampesotse (S. Zefania, T. Szekely and P. Long in litt. 2007). It can be found nesting in Marambitsy Bay (Zefania et al. 2008), although latest surveys from 2022 did not record any individuals there (Rabarisoa in litt. 2023). It is also present in other sites including, but not limited to, Boanamary of Mahajanga, Bemoramba in Maintiramo (ZICOMA 1998), the Mangoky River and Sambao River estuaries, and Baly Bay (R. Rabarisoa in litt. 2023). In January 1971, one individual was seen near Antananarivo, and in 1985 it was infrequently reported from the east coast near Manakara (ZICOMA 1999).
Behaviour This species is sedentary (S. Zefania, T. Szekely and P. Long in litt. 2007), and there is some evidence for genetic isolation by distance within the species (Eberhart-Phillips et al. 2015). It is monogamous, and pairs are highly territorial during the breeding season (Zefania and Szekely 2013). Nests can be found between August and May, but the most important breeding period is from December-April, with a peak in February at Tsimanampesotse (S. Zefania, T. Szekely and P. Long in litt. 2007). Habitat It is generally found at, or near to, sea level. Typically this species prefers drier areas than Kittlitz's Plover Charadrius pecuarius, and avoids flooded grasslands (del Hoyo et al. 1996). It favours saline lagoons and sandy coasts and estuaries, such as the Tambohorano wetlands, but can also be found in open alkaline grassland around, for example, Lake Tsimanampesotse. Breeding It breeds in areas of dry short, grazed grassland and Salicornia (Johnsgard 1981) near to the coast or around bodies of saline water including alkaline lakes, and brackish pools or lagoons. Non-breeding Roosts occur on sand spits facing the sea or a lake, or on sand dunes covered with creeping vegetation (Langrand 1990). It forages on intertidal mud, the open mud area of mangroves (del Hoyo et al. 1996, Morris and Hawkins 1998, S. Zefania, T. Szekely and P. Long in litt. 2007), and silty areas at river mouths, often in association with other coastal plover species (Johnsgard 1981, del Hoyo et al. 1996). Diet Its diet is poorly known, but it is thought to feed on invertebrates, mainly insects (Langrand 1990, del Hoyo et al. 1996). Breeding Site Its nest is a small scrape made in dry grassland (Morris and Hawkins 1998). Clutches of two eggs are most common, with some containing one (S. Zefania, T. Szekely and P. Long in litt. 2007). The incubation period is 27.3 ± 0.8 days, followed by a fledging period of 30.5 ± 2.5 days; hatching success has been recorded as 22.9%, with fledging success recorded as 41.4% (Zefania et al. 2008). Overall nest success was 9.5% in 2005. Adult survival rate is 0.79 and juvenile survivorship is 0.32 (Zefania et al. 2008).
Currently, the main threat to the species is mammal predation on nests, which reduces its breeding success (S. Zefania in litt. 2023, Long et al. 2008). The predator species are not yet certain, but suspected to include both native and non-native species, such as Pied Crow Corvus albus, Black Kite Milvus migrans, Grandidier's Mongoose Galidictis grandidieri, feral cats Felis catus, and feral dogs Canis familiaris (Wiersma and Kirwan 2020). Modifications of its wetland habitat on the west coast of Madagascar (for example the local development of shrimp farms in the Baly Bay and Besalampy area [Rabarisoa et al. 2007]), leading to habitat degradation and loss (Rabarisoa in litt. 2023) does represent an ongoing threat, however this is still limited, especially in saltmarsh habitats (S. Zefania, T. Szekely and P. Long in litt. 2007). The species may be particularly vulnerable to the aforementioned threats, as it exhibits low productivity, inflexible breeding behaviour and is a habitat specialist (S. Zefania, T. Szekely and P. Long in litt. 2007, Zefania et al. 2008). It may be vulnerable to egg collection locally, but most of the population lives in remote areas that have low human population densities (ZICOMA 1999), and the nests are difficult to find and rarely searched for (S. Zefania, T. Szekely and P. Long in litt. 2007). Grazing cattle will keep vegetation at a suitable height for this species, but they can create disturbance and cause mortality of chicks by trampling (Zefania and Szekely 2013). Competition with Kittlitz's Plover C. pecuarius and/or White-fronted Plover C. marginatus has been suggested as a possible threat, but there is little or no evidence for this (ZICOMA 1999).
Conservation Actions Underway
It is found in at least two protected areas (S. Zefania, T. Szekely and P. Long in litt. 2007), Lake Tsimanampetsotsa, an important site for the species, and Baly Bay National Park (Morris and Hawkins 1998). However, in general, mangroves, wetlands and coasts have little legal protection in certain parts of Madagascar (ZICOMA 1999). New surveys to update the population size and distribution, and to calculate recent trends are planned (S. Zefania in litt. 2023).
14 cm. A smallish, long-legged coastal plover. Crown and back mid-brown with paler feather fringes, giving mottled appearance, flight-feathers darker. Blackish eyestripes join on the lores, and are divided from the crown by a long narrow pale supercilium, joining on the nape and forehead. Underparts are whitish washed variably with orange, with a fairly wide black breastband. Long legs and feet pale grey. Similar spp. From White-fronted Plover C. marginatus and Kittlitz's Plover C. pecuarius by the strong black breast-band and from Ringed Plover C. hiaticula by the supercilium that circles the crown, the longer, duller greyish legs and paler, more mottled upperparts. Hints Occurs in coastal areas, especially in salt lagoons, shallow muddy pans behind mangroves, alkaline grassland near lakes and pools, and sandy estuaries, where it picks small invertebrates from the surface in typical plover fashion.
Text account compilers
Rutherford, C.A.
Contributors
Dodman, T., Hawkins, F., Long, P., Szekely, T., Zefania, S., Symes, A., Westrip, J.R.S., Taylor, J. & Rabarisoa, R.
Recommended citation
BirdLife International (2024) Species factsheet: Black-banded Plover Charadrius thoracicus. Downloaded from
https://datazone.birdlife.org/species/factsheet/black-banded-plover-charadrius-thoracicus on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 23/11/2024.