CHRISTMAS WRASSE · `awela
Thalassoma trilobatum (Lacepede, 1801)
These fast-moving wrasses inhabit
shallow reefs, often in the surge zone, where they feed mostly on
crabs and molluscs. Terminal males have bright ladderlike blue-green
markings on a reddish body. The brown and green initial phase adults
(both sexes) are smaller and drab by comparison. At night these
fish sometimes sleep in tide pools just above the water line where
they can be discovered by flashlight. Juveniles occur in tide pools.
The species name means "three lobes." At least ten Hawaiian
names have been applied to this wrasse, some to designate different
growth stages. To about 12 in. This is a common species throughout
the Indo-Pacific. Photos: Hanauma Bay, O`ahu. 3-5 ft.
initial phase (male
Christmas Wrasses spawn during daytime
high tides for much of the year. Drab initial phase fish of both
sexes aggregate at specific sites, often a large coral head or other
landmark, to spawn in groups. Terminal males hold spawning territories
scattered more widely along the top of the reef and mate with individual
females. To advertise themselves these males intensify their colors,
often becoming more reddish and turning their pectoral fins blue
or blue-black. They swim back and forth in an excited manner high
off the bottom, pausing now and again to flutter their blue pectorals
in an exaggerated and conspicuous display. The artificial reef at
Kahe Point Beach Park, O`ahu, is a good place to see this. One of
the "risers" for the outfall pipe was the spawning site
where these photos were taken..
initial phase fish
aggregating to spawn - Kahe Pt., O`ahu, 10 ft.