NATURAL HISTORY

HUMPHEAD WRASSE } Cheilinus undulatus
FAMILY: Labridae

DESCRIPTION: Humphead wrasse are enormous reef fish, having been measured as long as seven feet and weighing up to 420 pounds. The wrasse has thick, full lips and a forehead hump that becomes more prominent as the fish ages. Changing in color throughout their lifetimes, males range from bright electric blue, green, or purplish blue to a relatively dull greenish blue. Juveniles and females are primarily a red-orange color, which fades to white on their bellies.  

HABITAT: Sometimes referred to as “elephants of the coral reef,” adult wrasse inhabit a reef's outer slopes and steep drop-offs, showing fidelity toward particular sites. Juveniles are usually found among thickets of living staghorn corals.

RANGE: Humphead wrasse are found throughout the Indo-Pacific Oceans, from the Red Sea and the coast of east Africa to the central Pacific, south from Japan to Melanesia, and including U.S. Pacific territories such as Guam.

MIGRATION: Humphead wrasse do not migrate long distances. Local migration may occur.

BREEDING: Female humphead wrasse are able to change sex, which is a trait not shared by other wrasse. How this plays into reproduction is unknown. Taking five to seven years to reach sexual maturity, humphead wrasse are slow to reproduce. Pairs spawn as part of a larger mating group that may consist of more than 100 individuals. Their tiny eggs are released into the water and, once the larvae have hatched, settle to the ocean floor.

LIFE CYCLE: Humphead wrasse are long-lived for fish, known to survive for at least 30 years.

FEEDING: Using their ultra-tough teeth, humphead wrasse consume hard-shelled species such as mollusks, echinoderms, and crustaceans. These fish are one of the few predators of coral-reef-destroying species, such as the crown of thorns starfish.

THREATS: In the luxury food industry, which has seen a surge in popularity in many Asian countries, the wrasse has become one of the most sought-after species to be sold alive at fish markets. Humphead wrasse can fetch up to $220 per pound. Global warming also poses a significant threat to the fish; coral reefs are home to nearly a third of ocean species, yet they are among the most imperiled ecosystems in the world due to warming ocean temperatures.

POPULATION TREND: Although humphead wrasse have widespread distribution, the World Conservation Union has revealed a worrying decline in numbers. The species' total population has dropped by at least half in just 30 years, with some localized populations declining by as much as 90 percent.

 

Photo by David Burdick, NOAA