FishCommonVisible while snorkeling

Sohal surgeonfish

Acanthurus sohal

The striped sergeant of the reef crest: the sohal surgeonfish patrols the surf zone with an orange "switchblade" folded at its tail.

Photo: iNaturalist – (c) zsispeo, some rights reserved (CC BY-NC-SA)

The sohal surgeonfish (Acanthurus sohal) is one of the Red Sea's most elegant fish: fine dark pinstripes run along its whitish-grey body, its fins are edged in deep blue, and a bright orange patch at the tail base marks the family trademark – a razor-sharp, folding caudal spine. This "scalpel" gave surgeonfish their name, and in the sohal it is especially well developed. The species lives in the Red Sea and adjacent Arabian waters and nowhere else.

It is a fiercely territorial algae grazer: on the shallow, surf-washed edge of the reef it maintains its own "algae farm", which it defends against every intruder – another surgeonfish, a parrotfish, or the fin of an unsuspecting diver. It patrols the reef crest in restless zigzags, and when needed it turns side-on and flashes the orange spine like a warning signal.

Around Hurghada it lives on practically every wave-washed reef top: on the outer rim of the Giftun Islands, along the shallow crest of El Fanadir or on top of Sha'ab Sabina you can watch it working its territory for minutes on end, even while snorkeling. As a diver you meet it mostly at the start and end of the dive in the shallows – keep a couple of metres of distance and it will leave you in peace.

Did you know?

Its tail spine works like a switchblade: at rest it lies folded in a groove of skin, but in a fight it snaps out instantly and the fish wields it like a scalpel with sideways slashes of the tail.

How to behave around it

The sohal is not venomous, but its tail spine can inflict a deep cut, and it may charge you when defending its territory. Do not corner, feed or touch it – if you see it darting towards you, simply give it space and it will go back to its business.

Where can you meet it?

You will find it on every surf-washed reef top: a meeting is guaranteed on the outer rim of the Giftun Islands, along the El Fanadir crest and on shallow Sha'ab Sabina, even while snorkeling.

Frequently asked questions

Only if you provoke it. Its tail spine is as sharp as a scalpel and it defends its territory boldly, but it never bothers a diver or snorkeler who calmly swims past. Keep a couple of metres of distance and there will be no trouble.

Yes – in fact the sohal prefers exactly the shallow, wave-washed reef top where you snorkel. Around Hurghada it is one of the most commonly seen fish even from the surface.

Because of the razor-sharp, deployable spine at the base of its tail, which resembles a surgeon's scalpel. In the sohal it is highlighted by a bright orange patch – the sea's way of saying: look, but don't grab.