The Yellow Staghorn Damsel (Amblyglyphidodon ternatensis) is a small, deep-bodied damselfish with a laterally compressed profile, a green-to-silver body, and yellow pelvic, dorsal, and anal fins. The yellow pelvic fins of adults are the most reliable feature separating this species from its close relatives in the genus. It ranges through the tropical Western Pacific from Indonesia to the Solomon Islands, north to the Ryukyu Islands, and east into Palau and Micronesia, where it reaches roughly 3 inches in the aquarium.

In the wild, adults occupy coral-rich, sheltered coastal reefs at depths of about 1 to 15 meters, keeping close company with algae beds and branching staghorn corals. A well-planned aquarium mirrors that structure: 30 gallons is the accepted minimum for an adult, and the layout should include abundant live rock arranged into caves, overhangs, and clear territorial breaks. Extra swimming room and additional rockwork are worth providing when the fish is kept in a group or in a busy community, since broken sightlines do more than raw volume to keep disputes brief.

This damsel is an omnivore with a strong association with Acropora thickets, which supply both shelter and forage on the reef. In captivity it accepts a broad menu, and the best results come from rotating meaty and plant-based items rather than relying on a single preparation. Brine shrimp, mysis shrimp, and finely chopped clam or fish cover the protein side, while spirulina flakes and herbivore pellets supply the vegetable component.

Offer small portions several times each day rather than one large feeding. Frequent, varied meals help maintain the green and yellow coloration and are reported to take some of the edge off territorial behavior, which matters in aquariums housing more than one damsel. Frozen preparations thawed before offering are readily taken, and most specimens begin feeding promptly once settled.

Mysis Shrimp Brine Shrimp Chopped Clam Chopped Fish Spirulina Flakes Herbivore Pellets Frozen Preparations
Adults may aggregate on the reef, and spawning takes place within loose groups where each pair defends a small patch of substrate. Aquarium specimens are semi-aggressive: juveniles tend toward the passive end of that range, but territoriality increases with maturity, particularly where hiding places are scarce. Individuals generally pay little attention to unrelated fish while reserving their attention for conspecifics and similarly sized tankmates. During breeding, the male guards and aerates adhesive demersal eggs deposited on cleared coral or other hard surfaces.

If a group is planned, introduce all specimens at the same time and give them substantial space plus rockwork that interrupts lines of sight. This damsel is reef compatible and normally ignores corals and invertebrates. The one nuance worth planning around is nesting behavior: a spawning pair prefers coral skeletons or dead Acropora branches, but may strip tissue from living Acropora when no alternate surface is available. Including some bare hard substrate or dead branching coral in the aquascape gives a pair a better option.

FAQ

Frequently Asked Questions

About the Yellow Staghorn Damsel

  • What aquarium size should I choose for a Yellow Staghorn Damsel?
    A 30-gallon aquarium is the minimum for an adult. Because territoriality increases with maturity, additional swimming room and generous rockwork are prudent for a group or a mixed community.
  • Is it safe for a reef aquarium?
    Yes, it is reef safe and usually ignores corals and invertebrates. A breeding pair can clear a patch of living Acropora for egg laying if dead coral or another suitable spawning surface is unavailable.
  • Can several be kept together?
    Groups are possible when all individuals are introduced simultaneously and given ample space, live-rock refuges, and broken sightlines. Expect rising territoriality toward conspecifics and similarly sized fish as they mature, especially during breeding.