|Scientific Name:||Ctenochaetus marginatus|
|Species Authority:||(Valenciennes, 1835)|
Acanthurus marginatus Valenciennes, 1835
Ctenochaetus cyanoguttatus Randall, 1955
Ctenochaetus magnus Randall, 1955
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor/s:||Clements, K.D., Choat, J.H., Abesamis, R., McIlwain, J., Myers, R., Nanola, C., Rocha, L.A., Russell, B. & Stockwell, B.|
|Reviewer/s:||Edgar, G. & Kulbicki, M.|
Ctenochaetus marginatus is widespread in the eastern and central Pacific. It is common and abundant (offshore islands in the Eastern Tropical Pacific) in parts of its range. It is a minor component of the aquarium trade. There are no major threats known and it occurs in marine reserves in parts of its distribution. It is therefore listed as Least Concern.
|Range Description:||Ctenochaetus marginatus is found in some scattered localities in the tropical central and eastern Pacific. It occurs in the Marshall, Caroline, Kiribati, Tuvalu, Johnston, Marquesas, Society and Line Islands (Randall 2001a). This species occurs in the tropical eastern Pacific from Costa Rica to Colombia, including all the offshore islands.|
Native:Colombia (Malpelo I.); Costa Rica (Cocos I., Costa Rica (mainland)); Ecuador (Galápagos); France (Clipperton I.); French Polynesia; Kiribati (Gilbert Is., Kiribati Line Is., Phoenix Is.); Marshall Islands; Mexico (Revillagigedo Is.); Micronesia, Federated States of ; Panama; United States Minor Outlying Islands (Howland-Baker Is., Johnston I., US Line Is.)
|FAO Marine Fishing Areas:||
Pacific – eastern central; Pacific – southeast; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Ctenochaetus marginatus was common at Kosrae (R. Myers pers. comm. in Randall 2001a). It is common at Palmyra and Jarvis, Line Islands and Balcer and Howland in the northern Phoenix Islands (B.C. Mundy pers. comm. in Randall and Clements 2001). C. marginatus is common in Niutao, Tuvalu (Randall and Clements 2001). It is abundant at Clipperton and Cocos, uncommon throughout the rest of its tropical eastern Pacific range. According to Robertson and Allen (1996), this fish was frequent enough to have a resident population in Clipperton Atoll. Surveys conducted in the Galapagos (Edgar et al. 2004), Costa Rica (Dominici-Arosemana et al. 2005, Espinoza and Salas 2005, Figueroa 2001) and Colombia (Rubio 1986) did not observe this species, indicating that it may be quite rare in the tropical eastern Pacific region.|
|Habitat and Ecology:||
Ctenochaetus marginatus inhabits shallow, seaward reefs (Lieske and Myers 1994). Small schools may also be found in relatively turbulent waters of the surge zone (Krupp 1995). It was observed in small rapidly moving schools in moderately rough water in broad shallow surge channels on the lee side of Onotoa Atoll, Kiribati (Randall and Clements 2001). In the Gulf of Chiriqui, Panama, this species could be found over sand and rubble substrate (Dominici-Arosemena and Wolff 2006). 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).
Maximum age was recorded as 15 years at 25.1 cm (FL) in the Marquesas (J.H. Choat pers. comm. 2010).
The genus Ctenochaetus feed on fine detrital material. They whisk the sand or rocky substratum with their teeth and utilize suction to draw in the detrital material that consists of diatoms, small fragments of algae, organic material and fine inorganic sediment (Randall and Clements 2001). Species of Ctenochaetus share the presence of a thick-walled stomach (Randall and Clements 2001), this character is significant with respect to the nutritional ecology of this genus (Choat et al. 2002b).
There are no major threats to this species.
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. However, its distribution overlaps a few marine protected areas within its range.|
|Citation:||Clements, K.D., Choat, J.H., Abesamis, R., McIlwain, J., Myers, R., Nanola, C., Rocha, L.A., Russell, B. & Stockwell, B. 2012. Ctenochaetus marginatus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 18 April 2014.|