Yellowfin Surgeonfish
Acanthurus xanthopterus
Yellowfin Surgeonfish (Acanthurus xanthopterus) is a large reef surgeonfish of the Indo-Pacific that also occurs in the eastern Pacific and beyond through broad occurrence records. It grazes benthic algae and detritus on lagoons, reef flats, and seaward reef slopes, and has a razor-sharp tail spine.
Identification points
- Bright yellow pectoral fins and yellowish highlights on the fins
- Dark olive-brown to gray body that is laterally compressed and oval
- Single sharp caudal spine at the base of the tail, typical of surgeonfishes
Habitat
Coral reefs, reef flats, lagoon edges, and outer reef slopes over sand or rubble; often near drop-offs and surge channels where algae and detritus accumulate.
Bait notes
Not a common sport target. If taken incidentally, small bits of shrimp, squid, clam, or algae/seaweed-based baits may tempt it; tiny reef jig or sabiki-style pieces can also work.
Behavior
Primarily a daytime grazer that picks algae, film, and detritus from hard substrate. It often moves in loose groups or schools, is wary around divers and anglers, and uses its caudal scalpel for defense.
Caution
The tail spine is extremely sharp and can inflict deep cuts; handle with tools or gloves. Because it is a reef fish, local consumption advisories may apply and large tropical reef fish can carry ciguatera risk in some areas.
Fishing notes
Light tackle and small hooks are required; present baits close to reef structure and work very quietly. Avoid heavy pressure and be prepared for quick runs toward cover; many anglers release surgeonfish immediately.