|Scientific Name:||Acanthurus leucosternon|
|Species Authority:||Bennett, 1833|
Acanthurus delisiani Valenciennes, 1835
Acanthurus delisianus Valenciennes, 1835
Acanthurus leucosternum Day, 1889
Hepatus leucosternon (Bennett, 1833)
Rhombotides leucosternon (Bennett, 1833)
|Taxonomic Notes:||This species is a member of the Acanthurus achilles species complex known for their propensity to hybridize (Randall and Frische 2000). The four species in this complex (A. achilles Shaw, A.japonicus Schmidt, A.leucosternon Bennett, and A.nigricans) are thought to hybridize when their distributional ranges overlap (Craig 2008).
Acanthurus cf. leucosternon, a hybrid between A. leucosternon and A. nigricans has been recognized from the Cocos Keeling and Christmas Islands (Marie et al. 2007).
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Abesamis, R., Clements, K.D., Choat, J.H., McIlwain, J., Nanola, C., Myers, R., Rocha, L.A., Russell, B. & Stockwell, B.|
|Reviewer(s):||Davidson, L., Edgar, G. & Kulbicki, M.|
Acanthurus leucosternon is widespread in the Indian Ocean. It is generally rare in parts of its range but achieves high abundances in some areas (e.g., Maldives, east African coast). It is a targeted species and is commonly collected for the aquarium trade. There were differences in densities observed between fished and protected areas (Mclanahan et al. 1999). However, this species is found in a number of marine reserves in parts of its distribution. We recommend further monitoring of the species' population status and harvesting trends. It is therefore listed as Least Concern.
|Range Description:||Acanthurus leucosternon is found from East Africa to Natal, eastwards to the Andaman Sea, Lesser Sunda Islands of southern Indonesia at least to Komodo, including Christmas and Cocos Keeling Islands. There was one sighting from the Gulf of Oman (Randall 1995). It is not known from the Red Sea.|
Native:Bangladesh; British Indian Ocean Territory; Christmas Island; Cocos (Keeling) Islands; Comoros; French Southern Territories (Mozambique Channel Is.); India (Andaman Is., Nicobar Is.); Indonesia; Iran, Islamic Republic of; Kenya; Madagascar; Maldives; Mauritius (Mauritius (main island), Rodrigues); Mayotte; Mozambique; Myanmar; Oman; Réunion; Seychelles; Somalia; South Africa; Sri Lanka; Tanzania, United Republic of; Thailand; Yemen
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Indian Ocean – western; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
Acanthurus leucosternon is rare in the Cocos Keeling and Christmas Islands relative to Acanthurus cf. leucosternon and A. nigricans (Marie et al. 2007). It is generally rare in the western Indian Ocean. In Seychelles, less than 5 individuals/1,000 m2 were recorded. In Cocos, an average of 0.51 per 1,000 m2 (58 transects) were recorded. It is not abundant on continental or fringing reefs. Surveys in Mauritius, Reunion and Sri Lanka did not record it as an abundant Acanthurid (J.H. Choat pers. comm. 2010).
In the Maldives, it reaches fairly high abundances (average of 35 per 1,000 m2) and 318 per ha (Edwards and Shepherd 1992). It achieves high abundances in reef flats and was most abundant on reef slopes outside the atoll rim. Its density decreases with increasing depth (Sluka and Miller 2001). On the east African coast, 4.4 per 1,000 m2 were recorded in marine reserves (McClanahan et al. 1999).
Visual census surveys along the Aceh coast, Indonesia, recorded fish densities of 33 individuals/750 m2 at Pantai sirkui, 21 individuals/750 m2 at Teupin Layeu and 22 individuals/750 m2 at Teluk Pelabuhan (FMIPA 2007).
In Kenya, landings during 1978-2001 for families that are less important in commercial catches (e.g., scarinae and Acanthuridae) showed rising catches (1978-1984) followed by a general decline during the 1990s, but the landings for the scarinae showed a rising trend in recent years (Kaunda-Arara et al. 2003).
|Habitat and Ecology:||
Acanthurus leucosternon inhabits inshore reefs and is known to occur in large feeding aggregations. It is generally found on reef flats and along upper seaward slopes (Kuiter and Debelius 2001). It is classified as a grazer (Green and Bellwood 2009). The sexes are separate among the acanthurids (Reeson 1983). Acanthurids do not display obvious sexual dimorphism, males assume courtship colours (J.H. Choat pers. comm. 2010).
|Use and Trade:||Acanthurus leucosternon is commonly collected for the aquarium trade (Global Marine Aquarium Database accessed 19 March 2010). Online prices range from $69.99 - $99.00 (L. Rocha pers. comm. 2010). In the Maldives, the estimated export for the aquarium trade in 1986 was 6,200 individuals (Edwards and Shepherd 1992). It is a targeted food fish in western Thailand (Allen 2005) and in other parts of its range.|
Acanthurus leucosternon is a targeted fish species and is generally rare in parts of its range (J.H. Choat pers. comm. 2010). On the east African coast, differences were observed in densities between fished (average of 0.56 per 500 m2) and protected areas (average of 2.27 per 500 m2) (McClanahan et al. 1999).
Surgeonfishes show varying degrees of habitat preference and utilization of coral reef habitats, with some species spending the majority of their life stages on coral reef while others primarily utilize seagrass beds, mangroves, algal beds, and /or rocky reefs. The majority of surgeonfishes are exclusively found on coral reef habitat, and of these, approximately 80% are experiencing a greater than 30% loss of coral reef area and degradation of coral reef habitat quality across their distributions. However, more research is needed to understand the long-term effects of coral reef habitat loss and degradation on these species' populations. Widespread coral reef loss and declining habitat conditions are particularly worrying for species that recruit into areas with live coral cover, especially as studies have shown that protection of pristine habitats facilitate the persistence of adult populations in species that have spatially separated adult and juvenile habitats (Comeros-Raynal et al. 2012).
|Conservation Actions:||There are no species-specific conservation measures in place for this species. Its distribution overlaps several marine protected areas in parts of its range.|
|Citation:||Abesamis, R., Clements, K.D., Choat, J.H., McIlwain, J., Nanola, C., Myers, R., Rocha, L.A., Russell, B. & Stockwell, B. 2012. Acanthurus leucosternon. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 23 November 2014.|