Appearance

Appearance

Up to about 8 in (20 cm) long, with a tall, flat, disk-shaped body. A white scalpel-like spine near the tail is used for defense. At night the yellow fades and a brownish patch with a white stripe appears; the bright color returns quickly in daylight.

Look-alikes

Where it lives

Typical habitats

• Coral reefs
• Lagoons

Range

In the U.S., it lives around the Hawaiian Islands and in U.S. Pacific territories such as the Mariana Islands and Wake Island.

Preferred conditions

Shallow, coral-rich reefs about 7–150 ft (2–46 m) deep, in water around 75–82°F (24–28°C).

Behavior

Diet

Mostly a grazer on filamentous and turf algae, with some zooplankton.

Social life

Seen alone or in small groups.

Life cycle

Reproduction

Spawns year-round, peaking around the full moon. Eggs are released into open water with no parental care, and the drifting larvae can travel over 100 miles (160 km) before settling on a reef.

Lifespan

Can live more than 30 years in the wild.

Growing it

Care

A staple of home reef tanks, though it can be aggressive, is prone to marine ich, and may nip corals. Researchers first bred it in captivity in 2015, and captive-bred fish are now sold.

Connected species

Ties with other wildlife

Larger fish, sharks, crabs, and octopuses prey on it. In Hawaii it is one of the main fish at reef cleaning stations, nibbling algae off green sea turtles' shells.

Partners

• Green Sea TurtleChelonia mydas

  At Hawaiian cleaning stations the turtle gets a cleaner shell and the tang gets a meal of algae.

Close relatives

• Pacific Sailfin TangZebrasoma velifer

  Same genus, but striped instead of solid yellow; its zebra-like bands gave Zebrasoma its name.

Conservation

IUCN Red List

LCLeast Concern·Low risk of extinction

Threats

Hawaii once supplied most of the world's aquarium yellow tangs, with hundreds of thousands collected each year, mainly off West Hawaii. Commercial aquarium collecting is now halted in Hawaii, and proposals to reopen it remain contested.