I. Biological Description
Ahi refers to two species, bigeye tuna (Thunnus
obesus) and yellowfin tuna (Thunnus albacares).
In Hawaii, shibi is another name for yellowfin tuna.
The yellowfin gains its name because the soft
dorsal and anal fins and finlets are bright yellow in
color. The dorsal and anal fins lengthen with age.
Yellowfin range from the ocean surface to depths below 100 fathoms.
II. Of Special Interest For Buying/Distributing
Availability And Seasonality:
Caught year-round in Hawaii’s waters, yellowfin tuna is usually most
abundant during the summer season (May-September). There are wide fluctuations in the annual
catch of yellowfin, depending on whether ocean surface temperatures and other oceanographic
conditions favor the migration of ahi schools to within fishing range of the Hawaiian Islands.
Yellowfin tuna is landed in Hawaii by commercial and sport fishermen. A large part
of the commercial catch is harvested by longline boats, which may search for tuna concentrations up
to 800 nautical miles from port and set hooks in deep waters. Landings by the handline (ika-shibi)
fleet, based largely on the island of Hawaii, are impressive during some years. Trollers contribute the
remainder of the commercial catch of yellowfin, as well as all of the recreational catch. Trophy-sized
yellowfin tuna are prized catches in gamefishing tournaments held in Hawaii.
The longline catch and some of the handline (ika-shibi) catch of ahi is marketed through
the Honolulu fish auction. The majority of the handline catch is sold through the fish auction in Hilo
and through intermediary buyers on the island of Hawaii. The troll catch may be marketed through
fish auctions, intermediaries on all islands, or directly to stores and restaurants, or it may be shared
with family and friends.
Most ahi is sold fresh, but surpluses caught during the peak summer season are sometimes dried
Yellowfin and bigeye tuna are completely interchangeable for sashimi and other raw
fish preparations. Yellowfin is also interchangeable with other tunas and with a‘u for grilling. Yellowfin
is processed, interchangeably with ahi and a‘u, into smoked and dried products.
III. Of Special Interest For Preparation/Quality Control
Shelf Life And Quality Control:
Yellowfin is more perishable than either bigeye or albacore tuna (see
Table 3). Although the yellowfin’s flesh tends to be firmer than that of bigeye tuna, it does not retain the
natural red pigmentation as long. The quality of yellowfin caught off Hawaii varies considerably with
fishing method, care in handling and other factors.
Yellowfin Ahi (Yellowfin Tuna)