|Scientific Name:||Acrocephalus caffer|
|Species Authority:||(Sparrman, 1786)|
|Red List Category & Criteria:||Endangered B1ab(ii,iii,v);C2a(i) ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Gouni, A., Raust, P. & Blainvillain, C.|
|Facilitator/Compiler(s):||Khwaja, N., Mahood, S., O'Brien, M., Shutes, S., Stattersfield, A., Derhé, M.|
This species is listed as Endangered because it has a very small population and range, and it is now restricted to a single island where it is rare, localised and declining owing to disturbance and habitat degradation. Measures are urgently needed to regulate access to important breeding valleys and the collection of bamboo to slow its rate of decline.
|Range Description:||Acrocephalus caffer is found on Tahiti in the Society Islands, French Polynesia, having probably formerly occupied all the high islands in the group. The subspecies longirostris is probably extinct on Moorea although there have been at least two unconfirmed reports since 2000 (A. Gouni in litt. 2007, Cibois et al. 2008, A. Gouni in litt. 2011). The subspecies musae and garretti both went extinct on the islands of Raiatea and Huahine respectively, in the late 1800s or early 1900s. The species is absent from the Tahiti peninsula (Tahiti Iti) and has been rare and local throughout the 20th century, being recorded in six valleys during the period 1920-1923 (out of 14 visited) and 12 during 1986-1991 (out of 39), and estimated to number a few hundred individuals (Monnet et al. 1993b).|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The population is estimated to number a few hundred individuals by Monnet et al. (1993b). It is placed in the band 250-999 mature individuals, equating to 375-1,499 individuals in total, rounded here to 350-1,500 individuals.|
|Habitat and Ecology:||It occurs in bamboo thickets and second growth forests in river valleys and hillsides to 1,700 m. It feeds on insects but also takes lizards, small fish, crayfish, snails and nectar (Pratt et al. 1987, Thibault 1988). It is thought to breed exclusively in bamboo thickets (P. Raust in litt. 2007).|
|Major Threat(s):||The development of hydro-electricity opened up the interior of the island with new roads and tracks (P. Raust in litt. 2007). This increased access has lead to a considerable increase in the exploitation of bamboo as well as invasion by the neotropical weed Miconia and an increase in tourists in four-wheel drive vehicles. These factors have modified the habitat considerably, and most worryingly have caused a loss of breeding habitat, as well as causing disturbance to birds (P. Raust in litt. 1999, P. Raust in litt. 2007). The introduction of feral cats Felis cattus, rats Rattus spp. (A. Gouni in litt. 2012) and many alien bird species, including the aggressive Common Myna Acridotheres tristis, may also contribute to its rarity (Thibault 1988, Seitre and Seitre 1991).|
Conservation Actions Underway
Surveys are ongoing in the Papenoo Valley (C. Blainvillain verbally 2000). Conservation Actions Proposed
Resurvey the species in order to establish trends (C. Blainvillain verbally 2000). Control the exploitation of bamboo. Monitor numbers in easily accessible key sites. Investigate the severity of the threat caused by A. tristis and other predators. Consider control of predators at sites known to be important to the species. Protect important sites from habitat clearance through road and dam building and degradation by off-road vehicles.
Cibois, A.; Thibault, J.-C.; Pasquet, E. 2008. Systematics of the extinct reed warblers Acrocephalus of the Society Islands of eastern Polynesia. Ibis 150(2): 365-376.
IUCN. 2012. IUCN Red List of Threatened Species (ver. 2012.1). Available at: http://www.iucnredlist.org. (Accessed: 19 June 2012).
Monnet, C.; Thibault, J.; Varney, A. 1993. Stability and changes during the twentieth century in the breeding landbirds of Tahiti (Polynesia). Bird Conservation International 3: 261-280.
Pratt, H. D.; Bruner, P. L.; Berrett, D. G. 1987. A field guide to the birds of Hawaii and the tropical Pacific. Princeton University Press, Princeton.
Seitre, R.; Seitre, J. 1991. Causes de disparition des oiseaux terrestres de Polynésie Française. South Pacific Regional Environment Programme, Nouméa.
Thibault, J. -C. 1988. Menaces et conservation des oiseaux de Polynésie Française. In: Thibault, J.-C.; Guyot, I. (ed.), Livre rouge des oiseaux menacés des régions françaises d'outre-mer, pp. 87-124. Conseil International pour la Protection des Oiseaux, Saint-Cloud.
|Citation:||BirdLife International 2012. Acrocephalus caffer. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 06 March 2015.|