Home
>
Fish
>
Emperor Angelfish

Emperor Angelfish

Pomacanthus Imperator

Quick Facts

Scientific namePomacanthus Imperator

Other namesImperial Angelfish, Imperator Angelfish

SizeUp to 40cm

WeightUp to 1.5kg

FamilyAngelfish / Pomacanthidae

Distribution

Habitat & AU DistributionClear lagoons, reefs, and surge channels.

The Emperor Angelfish is one of the most striking fish on any coral reef. It grows to about 40 cm long and is dressed in bold horizontal stripes of yellow and blue with a dark mask across the face.
In Australia, Emperor Angelfish live along the tropical north. They reach as far south as the central New South Wales coast on the east side and the central Western Australian coast on the west.
Its range covers a huge sweep of the Indo-Pacific. It extends from the Red Sea and East Africa east to the Pacific Islands and north to southern Japan.
Young Emperor Angelfish look nothing like their parents. Juveniles are dark blue-black with rings of white and pale blue curving across their bodies, a pattern so different that early naturalists once thought they were a separate fish entirely.
As the fish grows, those rings gradually give way to the adult’s trademark stripes. The change happens slowly over months and is one of the most dramatic colour shifts of any reef fish.
Juveniles tend to hide under ledges and inside reef holes, often near cleaner shrimps. Adults move into more exposed areas of the reef as they grow, taking up territories along ledges and caves where coral growth is rich.
The Emperor Angelfish feeds mainly on sponges and sea squirts that grow encrusted over the reef. These are tough, chemical-laden animals that most fish avoid, but Emperor Angelfish are well suited to eating them.
Adults are territorial and will actively chase other angelfish away from their patch of reef. They are usually seen alone or moving in pairs along the reef face.
Emperor Angelfish spawn in pairs, releasing eggs and sperm into the open water where fertilisation occurs and the developing eggs drift away with the current.
Young Emperor Angelfish sometimes behave as cleaners, approaching larger fish and picking parasites and dead skin from their bodies. Even an ocean sunfish has been recorded accepting this service.
Adults are active by day and retreat into crevices and reef structure at night to rest.
Emperor Angelfish are thought to be long-lived. Some individuals in aquaria have survived for more than 20 years, and wild fish likely live for many years as well.
Because of their extraordinary colours, Emperor Angelfish are among the most photographed fish on the reef.

Species Interaction

Emperor Angelfish: A Reef Icon in Tanks and on Reefs

Snorkelling & Diving
Aquarium
Research & Rare Encounters
Ecosystem Role

For divers and snorkellers, the Emperor Angelfish is one of the most striking fish on Indo-Pacific reefs, found across Australia’s tropical north, the Great Barrier Reef, and down to the central New South Wales coast. Underwater photographers prize it for its bold adult livery and the dramatic transformation from juvenile to adult. It is also one of the most sought-after species in the marine aquarium trade, collected from wild reefs across the Indo-Pacific, with captive breeding attempted but still uncommon. Researchers study its striking ontogenetic colour change as a model of reef-fish development.

Species
Sustainability

Scientific Classification

Kingdom: Animalia
Phylum: Chordata
Class: Teleostei
Order: Acanthuriformes
Family: Pomacanthidae
Genus: Pomacanthus
Species: Pomacanthus imperator

Conservation Status

The Emperor Angelfish is listed as Least Concern by the IUCN, with populations considered stable and no major threats of extinction identified. In Australian waters it occurs across reef systems from Shark Bay and the Dampier Archipelago in WA through to Lord Howe Island and Port Stephens in NSW. Collection for the aquarium trade is the main commercial pressure on the species.