I. Biological Description
Opah or moonfish (Lampris regius) is one of the
most colorful of the commercial fish species avail-
able in Hawaii. A silvery-grey upper body color
shades to a rose red dotted with white spots toward
the belly. Its fins are crimson, and its large eyes are
encircled with gold. The moonfish’s large, round
profile may be the origin of its name. Moonfish
landed in Hawaii range from 60 to over 200 pounds
in round weight. A pelagic wandering species, it is often found in the company of tunas and billfish.
II. Of Special Interest For Buying/
Availability And Seasonality:
Opah are not found in
schools, and thus are not caught in any quantity. However,
individual fish are regularly hooked by longline boats
fishing over seamounts. Landings follow no set pattern in
any particular area, but the presence of opah at the depths
of longline fishing gear may be related to vertical migra-
tions from the deep up the slopes of seamounts in search
of food. Opah are taken on longline gear year-round, but
landings seem to peak in April-August.
All of the opah landed in Hawaii are caught by longlining over seamounts.
Virtually all opah landed by longliners is sold fresh through the Honolulu fish auction.
Rising demand for fresh fish, particularly in the restaurant trade, has increased the
interest in previously underutilized species, like the opah. This species has found a place on restau-
rant menus as a “catch of the day,” particularly when more popular species are unavailable.
III. Of Special Interest For Preparation/Quality Control
Shelf Life And Quality Control:
The shelf life (3 weeks) is apparently as long as that of some fresh
tuna species landed by the longline fleet (see Table 3). The first outward signs of deterioration are
faded skin colors and softness.
Product Forms And Yields:
The entire opah catch is marketed as whole, fresh fish. Most is filleted for
restaurant use, both in Hawaii and for export to the U.S. mainland. Between 30 and 40% of the
round weight can be recovered as fillets, and the average yield is 35% (see Table 5).