Hawaii's pelagic fisheries

Marine Fisheries Review, Spring, 1993 by Christofer H. Boggs, Rusell Y. Ito

Old-style longlines were made of rope and composed of individual units called "baskets" named for the bamboo containers they were stowed in (June, 1950). Each basket was made up of the float line, main line, and branch lines necessary for one segment of longline (one droop of the line). Poles with flags were attached to the floats to mark the gear, and longlining was generally referred to as "flagline" fishing.

Historical Development and Decline

Historically, the longline fishery was the second largest commercial fishery in the state after the pole-and-line fishery. By the 1930's longliners landed most of the 1,000 t (ca. 2 million lb) of yellowfin tuna, bigeye tuna, and albacore, Thunnus alalunga, landed in the Territory of Hawaii (June, 1950). After a hiatus during World War 11 the fishery quickly recovered, landing 900 t (2 million lb) of tuna, and 700 t (1.5 million lb) of billfish and other species in 1948. Landings continued to rise, reaching a record level of 2,000 t (4.4 million lb) in 1954 (Fig. 1A). The longline fishery declined in the late 1950's through the mid- 1970's to reach a similar level of landings as the commercial troll (Fig. 2) and handline (Fig. 3) fisheries.

In the early years most of the catch was reported to have been in HDAR statistical areas 2-20 n.mi. (3.7-37 km) off Waianae, Oahu, and off Kona, Hilo, and Hamakua, Hawaii (June, 1950). Shomura (1959) reported greatly improved catch rates for bigeye tuna by longline vessels fishing off the windward coasts (i.e., Hilo) in winter as opposed to the traditional practice of fishing off sheltered leeward coasts (i.e., Waianae, Kona). Hida (1966) reported a growing number of longliners extending their range 100-400 n.mi. south of Oahu, and noted that CPUE was better than average in the southern area.

The species composition of longline landings changed over time. During 1951-64, more than 50% of longline landings (by weight) were bigeye tuna, also called ahi (a Hawaiian name), ahi mebachi, or "bluefin." True bluefin tuna, Thunnus thynnus, are rarely caught by Hawaii fishermen. Before 1950 and in the 1970's bigeye tuna and yellowfin tuna (also called ahi) made up roughly equal proportions of the catch (Fig. 1A). The proportion of blue marlin in the catch was higher than that of striped marlin, Tetrapturus audax, in the early 1950's but striped marlin became more predominant from the early 1960's to the present (Fig. 1A). Both marlin species are also called au (the Hawaiian name) or "sword-fish," but they should not be confused with broadbill swordfish (Fig. 1B), which became the primary target species in the 1990's (Dollar(7)). Local common names for the pelagic species are often used for reporting catch statistics, resulting in some confusion.

The decline of the Hawaii longline fishery in the late 1950's through mids 1970's was characterized by a lack of new investment. Only a few new steel or fiberglass boats were built or added to the fleet between 1950 and 1982. Only 3 out of 11 boats surveyed in 1982 were built after 1970 (Hawaii Opinion(8)). Most longline vessels operating through 1982 were veterans of the 1940's and 1950's. Low profitability probably contributed to the lack of investment in new vessels.