Fish
Sergeant Major Damselfish
Abudefduf saxatilis · also called sergeant major
Fanning a cluster of eggs laid carefully against a rock, a male sergeant major damselfish stands guard nearby, its five bold black bars across a yellow-and-silver body resembling the striped insignia that gives this common Atlantic species its name.
Overview
The sergeant major damselfish, Abudefduf saxatilis, is native to ocean and coastal habitat across much of the Atlantic. Its bold, insignia-like striped pattern, dedicated male egg-guarding behaviour, and common presence across shallow reef and rocky habitat make it one of the most familiar and visually recognisable damselfish species in the Atlantic.
A name borrowed from military rank
The sergeant major damselfish’s five sharp black bars across a bright yellow-and-silver body create a pattern striking enough to be compared directly to military insignia, a fitting name for a fish whose males take their egg-guarding duties just as seriously.
Status
Least Concern, remaining widespread and common across suitable coastal and reef habitat throughout the Atlantic.
Sergeant Major Damselfish: common questions
Why is it called the sergeant major damselfish?
It displays five distinct vertical black bars across a yellow-and-silver body, a striped pattern resembling military rank insignia that gives the species its common name.
Do male sergeant major damselfish care for their eggs?
Yes, males guard a cluster of eggs laid on a rock or other surface, fanning them with their fins to keep them healthy until they hatch.
Is the sergeant major damselfish commonly seen?
Yes, it is frequently found in shallow reef and rocky habitat, often in large, loosely organised groups, making it one of the more commonly encountered damselfish species.
Where is the sergeant major damselfish found?
It is native to ocean and coastal habitat across much of the Atlantic.