email a friend
printable version
EN
White-breasted Thrasher Ramphocinclus brachyurus
BirdLife Species Champion Become a BirdLife Preventing Extinctions Programme Supporter
For information about BirdLife Species Champions and Species Guardians visit the BirdLife Preventing Extinctions Programme.

Justification
This species has an extremely small range, which is continuing to decline as coastal dry woodland is cleared to make way for agriculture, housing and especially tourism developments. Consequently it warrants Endangered status.

Taxonomic source(s)
AOU. 1998. Check-list of North American birds. American Ornithologists' Union, Washington, D.C.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Stotz, D. F.; Fitzpatrick, J. W.; Parker, T. A.; Moskovits, D. K. 1996. Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.

Identification
23-25 cm. Dark brown-and-white bird with long bill. Dark brown upperparts. White underparts. Red iris. Long bill, decurved near tip. Immature, entirely brown and develops white breast-patch with age. Similar spp. Grey Trembler Cinclocerthia gutturalis is larger, less two-toned, grey above and has white iris. Voice Limited repertoire of short, harsh calls, occasionally a musical tee-rou. Alarm call a harsh tschhhh. Juveniles located on ground by thin tseep calls.

Distribution and population
Ramphocinclus brachyurus occurs as two subspecies which differ in plumage and call notes. The nominate race is restricted to the Caravelle Peninsula on Martinique (to France) (Bulens et al. 1994, Temple 2005, P. Feldman and P. Villard in litt. 1998, H. J. Temple in litt. 2003), an area of c.5km2, and race sanctaeluciae occurs on the north-east coast of St Lucia between the Marquis River Valley and Frigate Island Refuge (Keith 1997, J. D. Gilardi in litt. 1999). Until 1993, the thrasher was thought to be restricted to the northern part of this area (Marquis-Dennery Knob), and population estimates and censuses in 1971, 1987, 1992 and 2003 suggested that the population in this northern area may be declining (J. D. Gilardi in litt. 1999, H. J. Temple in litt. 2003). In 1993, thrashers were discovered near the Frigate Island Refuge, and recent research suggests that this site holds the bulk (c.75%) of the global population. A comprehensive programme of searches on Martinique found no new subpopulations anywhere else on the island. Surveys in 2003 and 2004 indicated a global population of 1,300-2,600 breeding adults, 1,100-2,400 on St Lucia and c.200 on Martinique (H. J. Temple 2005). In 2006 and 2007, the St Lucia population still numbered about 1,200 individuals (Young et al. 2010). By 2011, the population on Saint Lucia appeared to be fewer than 900 birds, with under 800 in the southern population (M. Morton in litt. 2012).

Population justification
The population is estimated to number at least 1,300 mature individuals, equivalent to over 1,900 individuals in total.

Trend justification
The population trend was previously based on Temple (2005), but the rate of decline increased owing to construction of hotel that destroyed habitat containing 25% of population. Moderately rapid to rapid declines are therefore estimated. However, the largest subpopulation may be undergoing an even more rapid decline (M. Morton in litt. 2012).

Ecology
On both islands, it inhabits dry and semi-dry woodland and scrub with abundant leaf-litter, often in areas with a clear understorey but sometimes in dense thickets. In the northern part of its range on St Lucia (Petite Anse-Dennery Knob) it tends to occur along ravines and river-valleys, but in the rest of its range on St Lucia and Martinique it also occurs on dry hillsides well away from streams. It tolerates a degree of habitat degradation and is often found in secondary woodland and scrub, but although it is occasionally seen in clearings and smallholders' crop-fields, it does not breed in these man-made habitats (Temple 2005). It typically forages on the ground for invertebrates, small frogs and lizards, also taking berries (Keith 1997, Raffaele et al. 1998). Breeding apparently coincides with the onset of the rainy season, and the bulky open-cup nest is placed 0.5-3 m from the ground, usually in the fork of a thin sapling (Keith 1997, J. D. Gilardi in litt. 1999, H. J. Temple in litt. 2003). Eggs (usually two) are laid from May until August, and thrashers may rear more than one successful brood in a season (Keith 1997, J. D. Gilardi in litt. 1999,  H. J. Temple in litt. 2003). The specie sometimes breeds cooperatively - around one-third of nests have helpers, which are apparently retained offspring from previous years, and may be either male or female (Temple et al. 2009, H. J. Temple in litt. 2003). Chicks leave the nest before fledging, and continue to be fed on the ground (J. D. Gilardi in litt. 1999). On St Lucia, nesting success was 44% in 1997, 55% in 2001, 74% in 2002 and 44% in 2003, suggesting normal levels of nest predation for a tropical passerine (J. D. Gilardi in litt. 1999, H. J. Temple in litt. 2003). It is highly sedentary, and may reside permanently on or near breeding territories (J. D. Gilardi in litt. 1999). It occurs at high densities within its restricted range (Temple 2005), suggesting that it may be at carrying capacity, with population increases being unlikely to occur unless more habitat is created (H. J. Temple in litt. 2006).

Threats
The main threat to this species is habitat loss, perhaps compounded by the impact of predation by introduced mammals. On Martinique, habitat loss during the colonial era means that the species now has a tiny population restricted to a very small area (Temple 2005). Most of this is effectively protected, although some losses to agriculture, charcoal-burning and housing development continue (H. J. Temple in litt. 2006). On St Lucia, on-going habitat degradation and loss is caused by agriculture, charcoal-burning and wood-cutting, and there are potentially devastating plans to build a highway through the centre of the thrasher's range (J. D. Gilardi in litt. 1999). The Le Paradis resort and golf course is being constructed on St Lucia on a site that is estimated to hold c.25% of the global population (Temple 2005), and tourism development companies will soon own land equivalent to 35% of the global Extent of Occurrence (Young et al. 2010). By 2008, 84 ha (12% of the range of St Lucia's southern sub-population) had been cleared for golf course/hotel construction (M. Morton in litt. 2012). Construction was then halted, but still has planning permission; were it to continue, a projected 248 ha (35% of the southern range) would be lost (M. Morton in litt. 2012). In the northern part of the range on St Lucia, planning permission is being sought for 2 large estates the development of which would result in approximately 1,000 ha (60%) of the northern range being lost (M. Morton in litt. 2012). Small Indian mongoose Herpestes auropunctatus and rats Rattus spp. have been present on both islands since before 1900, implying that the thrasher is able to coexist with these predators, but they may place an unwelcome additional burden on an already small population. Nest-monitoring on St Lucia suggests that levels of nest predation are not excessive, but the situation could be different on Martinique, where rats and mongoose may be more abundant: further research is required. Because the thrasher is confined to narrow areas along the Windward coast, a major hurricane could have a severe impact (H. J. Temple in litt. 2003). Additionally, studies have shown the species to be a poor disperser, and it is likely that individuals cannot pass between the two subpopulations on St Lucia, limiting the potential for one population to "rescue" the other from a significant decline (Temple et al. 2006).

Conservation Actions Underway
The well-protected (albeit small) Caravelle Nature Reserve covers part of the species's range on Martinique. It is legally protected on St Lucia, but none of its St Lucian range falls within a protected area. On both islands, studies have been carried out to assess the population and threats, and on Martinique a plan exists to control introduced predators (Bulens et al. 1994, Temple 2005, P. Feldman and P. Villard in litt. 1998). Banding birds has facilitated detailed ecological and population research (Temple 2005, P. Feldman and P. Villard in litt. 1998, J. D. Gilardi in litt. 1999, H. J. Temple in litt. 2003). Conservation Actions Proposed
Monitor both island populations to assess trends. Establish protected areas and effectively protect coastal dry woodland and scrub within the thrasher's range on St Lucia, and prevent further habitat losses on Martinique. Allow adjacent farmland to regenerate into scrub woodland, providing additional habitat and allowing populations to expand. Conduct further research into the impact of predators on Martinique, and implement the predator control plan if deemed necessary. Control predators on St. Lucia (Young et al. 2010). Enact legislation on St Lucia to protect critical wildlife sites. Consult with the hotel developers on St Lucia to protect suitable areas of thrasher habitat in a private reserve (P. Cosgrove in litt. 2007). Safeguard patches of dry forest to the west and north of the Le Paradis tourism development site in Mandelé. Quantify the impact of the Le Paradis development. Preserve mature dry and riparian forest within the tourism development site in Mandelé (Young et al. 2010). Research the taxonomic status of the two subspecies.

References
Bulens, P. J.; Le Dru, A.; Tayalay, G.; Bonet, J.; Tanasi, M.; Barré, N.; Feldman, P. 1994. Premiers resultats sur un suivi de l'avifaune de la Presqu'île de la Caravelle.

Collar, N. J.; Gonzaga, L. P.; Krabbe, N.; Madroño Nieto, A.; Naranjo, L. G.; Parker, T. A.; Wege, D. C. 1992. Threatened birds of the Americas: the ICBP/IUCN Red Data Book. International Council for Bird Preservation, Cambridge, U.K.

Keith, A. R. 1997. The birds of St Lucia, West Indies: an annotated check-list. British Ornithologists Union, Tring, UK.

Raffaele, H.; Wiley, J.; Garrido, O.; Keith, A.; Raffaele, J. 1998. Birds of the West Indies. Christopher Helm, London.

Temple, H. J.; Hoffman, J. I.; Amos, W. 2009. Group structure, mating system and extra-group paternity in the co-operatively breeding White-breasted Thrasher Ramphocinclus brachyurus. Ibis 151(1): 99-112.

Temple, H.J. 2005. Ecology, cooperative breeding and conservation of the White-breasted Thrasher Ramphocinclus brachyurus. Thesis. Ph.D., University of Cambridge.

Temple, H.J.; Hoffman, J. I.; Amos, W. 2006. Dispersal, philopatry and intergroup relatedness: fine-scale genetic structure in the White-breasted Thrasher, Ramphocinclus brachyurus. Molecular Ecology 15: 3449-3458.

Young, R. P.; Baptiste, T. J. N.; Dornelly, A.; Temple, H.; Whitehead, H.; Young, H. G.; Morton, M. N. 2010. Potential impacts of tourist developments in St Lucia on the Endangered White-breasted Thrasher Ramphocinclus brachyurus. Bird Conservation International 20(4): 354-364.

Further web sources of information
Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note taxonomic treatment and IUCN Red List category may have changed since publication.

Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note taxonomic treatment and IUCN Red List category may have changed since publication.

Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note, taxonomic treatment and IUCN Red List category may have changed since publication.

Detailed species account from the Threatened birds of the Americas: the BirdLife International Red Data Book (BirdLife International 1992). Please note, taxonomic treatment and IUCN Red List category may have changed since publication.

Explore HBW Alive for further information on this species

Recuento detallado de la especie tomado del libro Aves Amenazadas de las Americas, Libro Rojo de BirdLife International (BirdLife International 1992). Nota: la taxonomoía y la categoría de la Lista Roja de la UICN pudo haber cambiado desde esta publicación.

Search for photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Isherwood, I., Mahood, S., Pople, R., Sharpe, C J, Temple, H., Wege, D.

Contributors
Cosgrove, P., Gilardi, J., Temple, H., Villard, P., Morton, M.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2014) Species factsheet: Ramphocinclus brachyurus. Downloaded from http://www.birdlife.org on 30/08/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 30/08/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - White-breasted thrasher (Ramphocinclus brachyurus) 0

Key facts
Current IUCN Red List category Endangered
Family Mimidae (Mockingbirds and thrashers)
Species name author (Vieillot, 1818)
Population size 1300 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 24 km2
Country endemic? No
Links to further information
- Additional Information on this species