Heeny S. H. Yuen is with the Honolulu Laboratory, Southwest Fisheries Center, ational Marine Fisheries Service, NOAA, Honolulu, HI 96812. A Night Handline Fishery for Tunas in Hawaii ped themselves with gear to catch the tuna. The exact year when the fishery HEENY S. H. YUEN started is not known. The first Oki­ nawans arrived in Hawaii in 1899 to work in the then burgeoning sugar Introduction To my knowledge, the only other industry (United Japanese Society of place where this method is used is in the Hawaii, 1971). It took another 7 or 8 Modern commercial fishing for Philippine Islands. There, virtually all years, however, for the immigrants to tunas brings to mind large superseiners of the commercial yellowfin tuna catch reach large numbers. By 1911, 12,000 and longliners with complicated and is made on night handlines (OswaW). were living in Hawaii. Allowing for costly equipment and gear. In contrast, Even in Hawaii this technique is used time to fulfill their contracts with the the rapidly growing night handline only by fishermen on the island of sugar plantations, I would guess that fishery for tunas near the island of Hawaii. Fishermen from the other the fishery for squid started in the Hawaii is remarkable in its simplicity islands in the State have not yet second decade of the 1900's. and effectiveness. This fishery catches adopted it. The information in this In the early years of the fishery the bigeye tuna, Thunnus obesus; yellow­ paper may stimulate interest in hand­ boats were powered by sail; by the fin tuna, T. albacares; and albacore, line fishing in other areas. 1930's up to about 40 motorized boats T. alalunga; on elementary gear, a This report includes a brief history of were involved. Until World War II the hook and line. the fishery in Hawaii, a description of fishery was primarily for squid. The The effectiveness of the method is the fishing method and gear, a descrip­ incidental tunas caught were known as demonstrated by its catch rate which is tion of the catch and its value, and a "ika-sibi" (squid-tuna in Japanese), the approximately two fish per hook per summary discussion. The data for this name by which the fishery is called night on the average. In comparison, report were gathered in 1976. Minor today. Because the boats were too catch rates of Hawaiian longline changes in method and new fishing small to have the large fish on board vessels are on the order of 0.03 fish per areas since then are incorporated in and did 110t carry ice to chill the catch, hook per day (Otsu, 1954). this report. these tunas were towed alongside the Because of its inexpensive require­ boat on the way to port. Consequently, ments, this method of fishing seems the ika-sibi had a reputation for having like a promising method for the many History poor quality and could not compete on financially impoverished island com­ In 1976 night handline operations the market with tunas caught on munities in the tropical Pacific Ocean for tuna in Hawaii were made exclu­ longlines. to utilize a marketable resource of sively from Hilo (population 28,500). The squid fishery stopped abruptly export value. Nevertheless night The following account of the origins of on 7 December 1941, with the Japanese handline fishing for tunas is not a the fishery are from interviews of attack on Pearl Harbor. Maritime widespread practice. oldtimers in the fishing community of restrictions prevented boats from that city as written references were not fishing at night for the duration of found. World War II. Immigrants from Okinawa are When the fishery was resumed after believed to have started the fishery. the war, three to four boats equipped They went out at night to catch squid with iceboxes targeted on the tunas. ABSTRACT-Night handline fishing as they had done in Okinawa. Occa­ Until 1971 the tuna-oriented part ofthe effectively catches tunas in localized sionally something large would strike fishery was limited to these few boats areas. The fishery for tunas by this and snap their lines. Upon checking by the market for fresh tuna. The entire method in Hila, Hawaii, experienced a rapid growth when high prices on the with the native Hawaiians they learned catch was sold on the island of Hawaii, fresh tuna market andfast air delivery to that the strikes were probably made by which had a popultion of 55,000­ distant cities made new markets for the large tuna. They subsequently equip- 63,000 during that period. By 1971 catch available. The simplicity of the fresh tuna prices had increased enough method and low cost ofequipment makes to make air shipment of tunas to other it a promising methodfor island cultures 'E. Oswald, South China Sea Fisheries De­ markets economical. By 1976 the night oflow technology to usefor developing a velopment and Coordinating Programme, fishery. The paper describes the fishing Makati, Rizal, Philippines. Pers. commun., handline fishing fleet had grown to method and gear in detail. 1976. about 30 boats, about half of which

August 1979 7 are turned on. Some fishermen use just the above surface lights and some use just the underwater light but most of them use both types. Typically 25-W and 50-W incandescent bulbs are used for the above surface and underwater ,------20 lights, respectively. Some fishermen use slightly brighter lights on moonlit nights. The first fishing operation is to catch the squid, NOlodarus hawaiiensis, for bait. Cross-sections of mackerel scad. Decaplerus pinnulalus, or frozen squid, Loligo opalescens, roughly I inch (3 cm) wide, are used as chum. Squid are caught by angling and gaffing. The hooks are baited with mackerel scad by cutting off the tail so that the body of the scad is the proper length to fit on the shank of the hook and inserting the shank of the hook through the length of the fish starting with the cut end and ending at the mouth. A light line or wire attached to the proximal tip of the shank is wound around the fish to keep it from falling apart. This makes it possible to use the same piece of bait repeatedly despite the squid bites that are inflicted upon it. The baited hook is tossed out about 5 li6° W I 5° m and slowly pulled back to the boat. Figure I.-Fishing locations of night handline fishery for tunas. In this manner the hook is used not only to hook squid but also to lure the school of squid to within gaffing range of the boat. were part-timers. In 1977 over 40 boats side, successfully used night handlines A few fishermen prefer to gaff the were involved in the fishery from Hilo in areas where the bottom is 4-5 km squid exclusively. In this case the squid and about 10 or so boats were fishing deep and relatively flat. They fished at are lured to the boat by tossing out a from Kona on the west side of the night at sites where tuna were located whole scad hooked through the head island. during the day (Morioka\ with a fish hook and retrieving it in the Geographic expansion of the fishery same manner applied to the squid . Fishing Operations was accompanied by an expansion in hook. In 1976 the only fishing area was the fishing season. In 1976 the handline In the past, fishing for tuna began located 24-32 km (15-20 miles) north­ fishing season was from July through after 5-10 squid had been caught. east of the port city of Hilo on the east December. This still holds true for the Today most fishermen bait their tuna side of the island. Since then the fishery east side of the island. On the west side lines with mackerel scad and proceed has expanded to other areas, the main of the island the season runs from with fishing while catching squid for ones of which are east of Hilo, south January to April. bait. In fishing for tuna the baited hook of Pohoiki, and the southern half of The boats leave port to get to the is lowered to 20-30 m. The fishing line the west side of the island (Fig. I). The grounds at sundown. Upon arrival the is tied to the boat with a restraining line areas fished are characterized by a engine is turned off and a parachute is to keep the hook at the desired depth. marked increase in slope of the bottom attached to the bow and lowered into The restraining line is fairly heavy, beyond the edge of the shelf that ajoins the water as a sea anchor. Two above about 18-34 kg (40-75 pounds) break­ the island. The depth of the shelf at the surface lights and one underwater light ing strength, because it is intended to edge is about 400 m in the areas on the set the hook when the fish strikes. east side of the island and 200 m on the Three well separated hooks are fished: 2R. Morioka, Hawaiian Telephone Company. west side. During 1978 a few fishermen P.O. Box 1510, Kailua-Kona. Hawaii 96740. One at the bow, one amidship, and one from Kona, a district on the western Pel's. commun., 1978. at the stern. Some boats fish a hook at

8 Murine Fisheries Review each corner of the stern and one squid. A typical squid jig (Fig. 2) has Above surface lights are 25-W incan­ amidship. one of the boats seems to a shank 25 cm long and eight prongs descent bulbs with polished metal fish more than three hooks at a time. each of which is 5 cm long. Variation reflectors. Usually two of these are While waiting for the tuna to strike, the in the jigs occur in the number of used. The underwater light, usually fisher:nen continue to fish for squid. prongs, which may be 6-10, and in the one, is a 50-W incandescent bulb that On the western grounds where squid linear dimensions, which vary about has been waterproofed and weighted. are scarce, squid fishing is often not 10 percent. The gaff (Fig. 3) is similar Brighter bulbs are sometimes used for done. The tuna hooks are baited with to the jig but with slightly longer moonlit nights. The lights are powered mackerel scad. prongs (7 cm). The handle is a by storage batteries. The baseball bat When a tuna strikes, the restraining straight piece of bamboo I m long and wooden mallet are used for line sets the hook and the fish is and 2 cm in diameter at the larger stunning fish. allowed to run until the outgoing line is end. A wide assortment ofboats is used in slow enough to be handled. The fish is The tuna fishing gear (Fig. 4) the fishery. These range from 6-m (20­ hauled by hand to the boat. At this consists of a hook, a leader, a lead foot) fiberglass skiffs to an 18-m (60­ point the fishermen differ in their weight, and a line. The hook (Fig. 5) foot) boat that fishes longlines during techniques; some stun the fish and then is of a Japanese design (Tonkichi3 the off-season. The boats are usually gaff it; others stun the fish after it is on BKM #54). The leader is either seven­ manned by two men, but fishermen board. Fish are stunned with a blow on strand stainless, 227-kg (500-pound) will often go out alone. the head with a baseball bat or a test, wire or monofilament nylon of wooden mallet. Recently many fisher­ similar strength, sometimes braided for men have resorted to killing the fish by easier gripping. The leader length shooting it in the head with a handgun preferred by most is about I m but when it is alongside the boat. leaders 0.6-1. m are used. The weight When there is a strike at least one of (Fig. 5) is a lead tube of 227-397 g (8-14 the other two lines is removed from the ounces). The tube is bent at the middle water as soon as possible to reduce the about 30° to keep it from rolling possibility of the lines tangling. This around on the boat. A stainless steel practice is not followed when the tuna rod is placed through the tu be and its is small enough to land quickly or ends are fashioned into eyes to facili­ during times when strikes are infre­ tate the attachment of line and leader. quent. Tuna strikes tend to be clustered The favorite material for the lines is and while it is possible to keep two lines polypropylene rope either 0.95 cm (Ys with struggling fish from tangling, it is inch) or 0.79 cm (5/16 inch) in almost impossible to do so with three diameter. Lengths of the line range lines. The fishermen claim that tuna from 110 to 130 m. The fishing gear is schools move away when the lines get coiled and kept in a square wooden tangled. box for easy handling. The fish are stored in iceboxes with a Other equipment used by all boats mixture of ice and seawater. Whenever are a parachute, lights, and a baseball the catch exceed the icebox capacity, bat or a wooden mallet. The parachute excess fish are left on deck, covered is 7.2 m in diameter and equipment with wet canvas or burlap, and cooled surplused by the military. The lights, periodically with seawater. Departure used for attracting squid, are of two from the fishing grounds is timed so types: Above surface and underwater. that the fish can be delivered in time for the 7:00 a.m. auction. The newer and JReference to trade names or commercial firms faster boats can thus stay on the fishing Figure 2.-Drawingofa hook for does not imply endorsement by the ational catching squid. grounds longer. Marine Fisheries Service, NOAA. Gear Two sets of gear are used, one for catching squid and the other for Figure 3.-A squid gaff. catching tuna. There is much indi­ vidual variation in the choice of I~ materials and design of the gear. The - following description is of the most - typical gear. -- Jigs and gaffs are used to catch

August /979 9 - \ Catch Data on the catch, i.e., species, date of capture, number of fish, weight of each fish, and ex-vessel price for the years 1973-75 inclusive, were made available by Suisan Company, Ltd., which handled the sales of virtually all the catch of the night handline fishery at that time. On the sales records, weight is expressed in whole pounds. In the data analyses the pound was retained as the unit of weight. In the following presentation where weight is given to 0.1 kg, it is simply the metric equivalent of the original expression in pounds and was not meant to convey any implied precision. The weight and value of the total / catch are tabulated by species and year in Table I. The annual weights and Figure 4.-Photograph of a unit of handline gear. values for all tunas com bined show a consistent growth of the fishery from 89,000 kg (196,000 pounds) to 155,000 kg (341,000 pounds) and from $131,000 to $328,000 over the 3-year period. The annual catches of the individual species, however, show a wide vari­ ation between years with 2 years having about the same catch and I year having a much greater catch. For the bigeye tuna, the catch in 1974 was almost twice those of the other 2 years. The catch of yellowfin tuna in 1975 more than tripled the ca tches of the previous 2 years. The catch of albacore, also • high in 1975, was almost 60 times as great as the catch for the other years. The catch of squid reported in Table I is the amount sold at auction and represents the amount caught in excess of the squid used for bait. Bigeye tuna ca ught in this fishery range in size from 2.3 to 128.3 kg (5-283 pounds). Frequency distributions of ., weight by year (Fig. 6) show that most - ~ ~

Bigeye tuna 65.4 1202 63,0 144,2 2650 139,0 1026 2498 149,5 year to year (Fig. 7). The median Yellowfin tuna 23.3 229 755 513 50.5 1664 380 384 157.0 weight is a good example of the Albacore 04 0.2 16.1 0.8 0.4 35.5 0.5 0.2 210 All tunas 89.0 143.3 154.6 196.3 3159 340.9 131.1 288.4 327.5 variability. It was 21.8 kg (48 pounds) Squid 50 1.7 1.3 ttl 37 2.8 62 35 3.5 in 1973,81.6 kg (180 pounds) in 1974,

10 Marine Fisheries Review and 56.2 kg (124 pounds) in 1975. 700 Albacore had a much more limited size 1973 range than the other species, 15.4-34.5 600 kg (34-76 pounds) (Fig. 8). There was one unusual individual of 3.2 kg (7 500 pounds). The monthly distribution of catch 400 for the years 1973 through 1975 (Fig. 9) show peak catches for yellowfin tuna 300 and albacore during September and October, respectively. Bigeye tuna 200 catches were more evenly distributed in 100 time than the other species. October and September were the leading months. Mention was made earlier of the >- c~tch u 500 1974 high positive deviations in the of z bigeye tuna in 1974 and yellowfm tuna '":::> fil and albacore in 1975. The bigeye tuna 0:: 400 catch of 1974 and the yellowfin tuna lL catch of 1975 were compared with the catches of the other 2 years with respect to fish size and month to analyze the increase. More specifically, the average monthly catch in weight for each 4.5-kg (lo-pound) weight class of 1973 and 1975 was subtracted from its corre­ sponding catch in 1974 for bigeye tuna; the average monthly catch for each 4.5­ kg (Io-pound) weight class of 1973 and 1974 was subtracted from its corre­ sponding catch in 1975 for yellowfin tuna. The results for bigeye tuna (Fig. 10) I 51 101 251 291 I I I I I show that for the months of July and 10 60 110 260 300 August 1974 catch was slightly better WEIGHT CLASS (POUNDS) 0.5 23.1 45.8 68.6 91.2 113.9 132.0 than in the other years. The increase in I I I I 1 I I catch was distributed fairly evenly over 4.5 27.2 49.9 72.6 95.3 117.9 136. r the remaining 4 months of the season. WEIGHT CLASS (kg) Figure 6.-Frequency distribution of weights of bigeye tuna caught in the Contributing most to the 1974 increase night handline fishery for lunas. was the December catch of 5.0- to 40.8­ kg (11- to 9O-pound) fish. Other major contributors to the increase in order of magnitude were the 68.5- to 104.3-kg tuna catch based on size at age infor­ 0.90, respectively. Calculations were (151- to 23O-pound) fish in ovember mation of Shomura and Keala (1963) not made for the obviously anomalous and October, and the 27.7- to 45.4-kg who assumed that spawning occurred year of 1974. (61- to lDO-pound) fish in September. in April. Since the fishing season has its The 1975 increase in yellowfin tuna peak half a year from the spawning Discussion catch was concentrated in the month of season the fish were assigned mid-year September (Fig. II). Two-thirds of the ages. The catch curves constructed The growth of the Hawaiian night increase in catch was made in Septem­ from the data (Fig. 12) indicate that handline fishery for tunas was depen­ ber, 17 percent in October, and 15 per­ recruitment is complete at age 2.5 years dent on two major factors: I) The in­ cent in November. The largest increase and possibly a year earlier as suggested creased demand for fresh tuna of high in weight was in the 91.2- to 113.4-kg by the data of 1973. Instantaneous quality for "sashimi" (a Japanese raw (201- to 25O-pound) group. There was rates of total mortality for fish between fish dish) and 2) the ability of modern also a large increase in the 41.3- to 68.0­ ages 2.5 and 7.5 years estimated from transportation systems to speedily kg (91- to ISO-pound) group. lines of least squares fit for 1973 and deliver the fish to markets as much as Ages were assigned to the bigeye 1975 resulted in Z values of 0.73 and 6,400 km (4,000 miles) from the fishery.

August /979 II 400

1973 200 350

150 300

a: w CD 250 ::0 ::J Z a: 200 w u>- CD z ::0 W ::J ::J Z 0w 150 a: ~

0 I 91 / 1975 I I 100 10 100

WEIGHT CLASS (POUNDS) 50 05 23.1 41.3 I I 1 45 27.2 45.4

OLI--'=''''==l'---1~~~.J::....<.~.....LL"'-±...... dZ~ WEIGHT CLASS ( kg) 291 I I 10 300 Figure 8.-Frequency distribu­ tion of weights of albacore WEIGHT CLASS (POUNDS) caught in the night handline 0.5 23.1 45.8 68.6 91.2 113.9 132.0 I I I 1 1 I I fishery for tunas. 4.5 27.2 49.9 72.6 953 117.9 136 I WEIGHT CLASS (kg) Figure 7.-Frequency distribution of weights of yellowfin tuna caught in the night handline fishery for tunas.

40,---,---,-----,r-----,---,----,

30 BIGEYE TUNA One of the problems of the fishery, National Marine Fisheries Service which is handled expediently at the (NMFS) is now working to identify the local level and accentuated by remote cause of the burnt condition with the marketing, is the problem of "burnt" goal of preventing it. As an interim tuna. Tuna are labeled "burnt" when measure NMFS is also working on a the normally dark red, translucent field method to test for burnt tuna 50 YELLOWFIN TUNA flesh is light pink, opaque, and slightly before the fish is sent to market. J: ~ 40 sour in taste. Burnt tuna is considered The successful development of the U to be less desirable than normal tuna night handline fishery in Hawaii ::l 30 8 and sells at a lower price. "Burnt," depended heavily on knowledge of a. 20- however, is not a clear-cut condition, '"

pounded when the seller who must stored for later shipment and would be O'--""=..J.~...... L accept the distant buyer's judgment of ineligible for the blue chip, fresh fish JULY AUG. SEPT. OCT. NOV. DEC. Figure 9.-Proportion of indi­ quality begins to doubt the integrity of market. Two market options would vidual species total caught each the buyer. still be open, however. The first, and month. Data of 1973 through The Honolulu Laboratory of the probably less profitable ofthe two, is to 1975 combined.

/2 Marine Fisheries Review :.. s:: 2~~ ~ ~JU:LY: OQ ;;; : ~ ~LY: s:: ;;;j '":1 ••• ' •' ••• I ~ =:= ' ••• •,• ...... \Q 'J \Q ~b :~ ::;; ::~ d!fA~GU~ ; j 8000 :~I:- ~A=~ SEPTEMBER III ••• :I i I: •••• J 6000 : (I) • o -~I 8 4000 Iii iii i if iii Ii; iii iii I iii Iii i a. (I) 2000 zo 8000 SEPTEMBER '" :::> ~ 01 _",cr'0 ~-~ ~ 7000 '" ~ -2000 '"~ ~"' a: , -4000 '"~ 5000 ...... '"en -6000 ~ 4000 ~ , o -8000 .... 3000 e: I I,I 11 l II, !!! I !,, !, ! II ! IIIII ! ! I !!!'" ~ Ii? ... 1000 :I: U ~ a !~LLi~B:J U "'~ -1000 ... o -2000 z o ~ -3000' !! !!! !!! III! ! II,!III!III!!! I ~ ~c;;: ~ ;;: ,• :V;:ER'l '"o -~[~~ ~l-=:: : 51 101 :;::]151 201 251 291 I I I I I 10 60 110 160 210 260 360 ~k~.;~ I~, ~~EMBrn_J I .' I • I II I 1 WEIGHT CLASS (POUNDS) ; It 0.5 23 I 45.8 68.6 91.2 113.9 1320 I I I I I I I I 51 101 151 201 251 291 45 27.2 49.9 72.6 953 1179 136.1 I I I I I I I 10 60 110 160 210 260 300 WEIGHT CLASS (kg) WEIGHT CLASS (POUNDS) 0.5 23 I 45.8 68.6 91.2 1139 132.0 Figure 1D.-Deviations of the 1974 catch from the average catch of 1973 I 1 I I 1 I I and 1975 for bigeye tuna. 4.5 272 49.9 72.6 953 117.9 136.1 WEIGHT CLASS (kg) Figure I I.-Deviations of the 1975 catch from the average catch of 1973 and 1974 for yellowfin tuna...... w 2000 A----__ 1000 800 600

400

200

100 a- 80 ::> 0 a:: 60

'"~ 40 " a:: " CD "'::IE ::>z 20

0------<> 1973 101------1 x------x 1974 f-----­ 8 O-··_··_··-

4

2

I 0 4 5 6 8 AGE (YEARS) Figure 12.-Catch curve for bigeye tuna.

sell the catch to canneries. The second Agent in Hilo, made a conscientious is to sell the fish on the sashimi market. review of the manuscript. The latter option is available ifthe flesh quality of the tuna is maintained by Literature Cited storing at -50°C. Otsu, T. 1954. Analysis of the Hawaiian long­ Acknowledgments line fishery, 1948-52. Commer. Fish. Rev. 16(9): 1-17. The Suisan Company, Ltd., of Hilo, Shomura, R. S., and B. A. Keala. 1963. Hawaii, provided the catch and price Growth and sexual dimorphism in growth of data. I gratefully acknowledge the will­ bigeye tuna (Thunnus obesus) a preliminary report. In H. Rosa, Jr. (editor), Proceedings ing assistance of Zenso Kanai and Hiro of the World Scientific Meeting on the Nishimura of Suisan Company, Ltd. Biology of Tunas and Related Species, 2-14 July 1962. FAO Fish. Rep. 6, vol 3, Kanai made the records available. p. 1409-1417. Both made arrangements for me to United Japanese Society of Hawaii. 1971. A interview fishermen and to board fish­ history of Japanese in Hawaii. Publication Committee, United Japanese Society of ing boats for field observations. Hawaii, J. Okahata, Chairman, Honolulu Howard Takata, Marine Advisory XIX, 431 p.

/4 Marine Fisheries Review I