Acanthurus bahianus

Ocean surgeon | Grey Doctorfish | Barber | Ocean Surgeonfish | Ocean Tang | Ringtail | Shitty Trooper | Doctorfish
Acanthurus bahianus
Acanthurus bahianus, Abrolhos, Bahia, Brazil, Photo: Graham Edgar


Tropical Atlantic/Caribbean


Olive-brown body, oblique blue stripe from snout to eye, an arc of sort blue stripe behind rear edge of eye, and black rear edge of gill cover. Outer tail margin yellow, rather than white/blue as in A. tractus, with which this species was previously grouped. This species only southern Atlantic, and not known from the Caribbean.


Max Size: 38 cm

Sea Temperature Range: 22.3-30.9°C

Depth: 2-40m

Habitat Generalization Index: 24.05

Also referred to as the SGI (Species Generalisation Index), this describes the habitat niche breadth of the species. Species with values less than 15 are found in a relatively narrow range of reef habitat types (specialists), while those over 25 may be found on most hard substrates within their range (generalists). Learn more here.

Conservation and Rarity

IUCN Status: Least Concern

Occurrence: Common (25.7% of sites)

Occurrence describes how often the species is found on surveys within its distribution. It is calculated as the % of reef sites surveyed by RLS divers across all the ecoregions in which the species has been observed

Abundance: Many (16 per transect)

Abundance is calculated as the average number of individuals recorded per RLS transect, where present.