HISTORY OF DRIFTNET FISHERIES IN OPERATION


The North Pacific Squid Driftnet Fishery

Participants and Target Species The North Pacific squid fishery was dominated by Japan, the Republic of Korea (ROK), and Taiwan (Republic of China). Driftnet mesh sizes were designed to harvest three species of "red" squid: the neon flying squid, Ommastrephes bartrami, (aka-ika), the principal fishery, and to a lesser extent two other oceanic squids: boreal clubhook squid and boreopacific gonate squid. The neon flying squid driftnet fishery was conducted on the high seas in the North Pacific Transition Zone and the Subarctic Frontal Zone. Horizontal distribution of the targeted species is highly correlated with surface temperatures: 15 deg - 24 deg C in July and August; 10 deg C - 22 deg C between September and December (Wetherall 1989). Vertical distribution is limited by the 10 deg C isotherm.

Driftnet Characteristics Squid driftnets are made of transparent, monofilament nylon and manufactured in panels (tans) 812 meters deep and 3060 meters wide (Jones et all 1990). The stretch mesh size that was employed varied with the fleet and with the time of year. Mesh sizes increased as the squid grew during the fishing season. Individual panels were attached together to form sections a few kilometers long. Most of the larger vessels deploy 810 sections per night (10001100 tans) or between 40 and 60 kilometers (Wetherall 1989; Joint Report 1990). The sections were strung along a float line with 100 to 1000 meters between sections. Sometimes sections were set parallel to one another and/or a fleet of vessels would form an array of nets. A lead line was attached to the bottom of the driftnet to stretch it out. The float line employed approximately 60 small floats per tan. A driftnet is difficult to see in the water, particularly when there are waves, and larger buoys, flashing lights and radio beacons were usually attached to help locate the driftnet in the dark early morning hours when it was retrieved. Anything equal to or larger in diameter than the targeted species that swum into the driftnet was likely to be caught. The nets are very flexible and tend to envelope large animals. The actual net configurations vary between the fleets (Joint Reports 1991; Jones et al 1990): Japan: 100135 mm mesh, tan 3060 m long (average 4550 m) and 711 m in depth; tans were attached in 56 km sections; 810 sections were strung along the float line to form a 5062 km driftnet (1100 tans). Republic of Korea: 86115 mm mesh, pok (tan) 50 m long and 812 m in depth (average 10 m); tans were attached in 150230 pok sections; 56 long sections were strung along the float line to form a 5069 km driftnet. Taiwan: 75160 mm mesh, tan 3040 m long and 910 m in depth; tans were attached in 350650 tan sections; 24 very long sections were strung along the float line to form a 3060 km driftnet.

Areas and Seasons The North Pacific squid driftnet fleets generally fished in an area between 35 deg - 46 deg N and 140 deg - 145 deg W. (Figure 1) In May of 1981, the Japanese government relegated its squid driftnet fleet to a zone east of 170 deg E to avoid having it compete with the Japanese albacore pole and line (bait boat) fleet and surume-ika squid jigging fleet. By fishing east of 170 deg E, however, the Japanese driftnet fleets competed with the United States albacore trolling fleet. The squid stocks and the fleet generally moved north and east as the fishing season progressed. The squid fishing season ran between late April and December. Taiwan generally fished for squid four to seven months a year (May-November), between 156 deg E and 155 deg W.

The driftnet fleet fished inside a moving northern boundary east of 170 deg E, which shifted between 40 deg and 46 deg N, depending on the month, to minimize the incidental take of salmon. This boundary was originally set to reflect a moving temperature gradient that supposedly separated squid stocks from salmon stocks. Neon flying squid generally stay in waters between 15 - 24 deg C (July-August) and 10 - 22 deg C (September-December). However, research indicates that (1) the locations of the temperature gradients vary significantly from year to year from their supposed locations (Figure 2) and (2) that salmon and squid stocks intermingle to some extent. Sockeye salmon were caught by research driftnets in 14 deg C waters in September, pink and chum salmon in waters between 11 deg and 1516 deg C during June-September, coho salmon in waters between 12 deg and 1516 deg C during June-September, and chinook in waters 1213 deg C (Burgner and Meyer 1983). By international agreement the Japanese, South Korean, and Taiwanese fleets were required to driftnet south of the northern latitudinal boundaries. (Table 1) However, squid vessels were frequently found fishing north of the boundaries. In 1989, the Japanese government unilaterally announced that it was going to permit its driftnet vessels to fish as far north as 48 deg N. In 1991, the July boundaries for Japan were 43 deg N; for Taiwan and South Korea 42 deg N.

Vessels and Crew Japan: In 1978, Japan began driftnetting for squid with some 170 vessels, mostly recruited from her salmon driftnet fleet. The number of vessels engaged in driftnet fishing increased to 534 by 1981. Although the total number of Japanese driftnet vessels was down to 457 by 1990, the fleet was now dominated by larger, more efficient and relatively new vessels, with gross registered tons (GRT) varying between 50 and 500 GRT. (In 1981 there were 371 small and 163 large class vessels; in 1990 there were 195 small and 262 large class vessels.) The Japanese government also instituted a permitting system. Four month (1 August -30 November) and seven month (1 June - 30 December) permits were available. The number of vessels requesting seven month permits increased through most of the 1980s (Herrfurth 1988). The average crew size was between 14 and 18, including officers (Yatsu 1990).

Republic of Korea: In 1979, the ROK began driftnetting for squid in the western North Pacific. In 1980, the ROK had a fleet of 14 vessels; in 1983, 99 vessels. In 1988, the Korean government reported that 30% of its driftnet fleet was between 10 and 20 years old; the rest were older than 20 years. In 1989, the ROK fleet numbered 157 vessels. In 1991, the number was down to 142 vessels between 170500 GRT, with an average of 300 GRT. The crew size was relatively large, between 20 and 28 men (Jones et al 1990). The ROK squid driftnet fishery began its driftnet fishing season late in April, near 35 deg N, 165 deg E, and moved north and east (Herrfurth 1988). There were also reports that North Korea was driftnetting for squid in the North Pacific.

Taiwan: In 1980, Taiwan began driftnet fishing for squid with 12 vessels. By 1984, the number had increased to 146; in 1988, it numbered 179. By 1990, the number decreased to 138, although the average GRT was not known. It was estimated that by the end of the 1980s the size of most of the Taiwanese squid driftnet fleet was between 350 and 500 GRT, although there were some vessels as large as 700 GRT (Jones et al 1990; Herrfurth 1988). In the early 1980s most of the vessels were quite old. However, by the end of that decade large, efficient, multipurpose fishing vessels had replaced many of the older vessels, which were either scraped or leased or sold to the Peoples Republic of China (PRC) through brokers in Hong Kong. Vessels flying the PRC flag were spotted driftnet fishing in the North Pacific in 1990, 1991, and 1992. The average crew size was between 16 and 18 (Jones et al 1990). Government regulations require that two thirds of the crew be Taiwanese. However, the actual figure was and is generally less than fifty percent, with most of the foreign crew coming from the Philippines and Mainland China.

Operations Driftnets were set in the late afternoon and early evening. It took two to four hours to set the net, depending on its length. The net was left to drift for about eight hours before retrieval began in the early morning. Retrieval took between six and 14 hours depending on the total length of the net and the amount of catch and by-catch. Sections of very long nets were sometimes left out more than one night (1990 Report). The many hours involved in setting, drifting and retrieving resulted in a large percentage of dead and spoiled by-catch, particularly tuna. Sometimes one end of the driftnet was kept attached to the catcher boat to keep it stretched out. Large buoys, flashing lights and transponders were often attached to the net to help locate it in rough weather. Sections of driftnets were frequently lost or torn. Since driftnets are difficult to mend and easily replaced, usually after one or two seasons of use, there was a great temptation to discard damaged net at sea, particularly if a large animal was hopelessly entangled in it. It was conservatively estimated that more than 1000 kilometers of squid driftnet were "lost" each year.

The Catch and By-Catch Each year between 250,000 and 300,000 metric tons of the target species, neon flying squid, were caught by driftnets in the North Pacific, with a landed value exceeding US$250 million (U.N. Secretary General's Report 1990; Wetherall 1989). The target squid catch was processed and frozen as soon as it was brought on board. The more valuable species in the by-catch were also kept, including the fins of sharks. The rest was discarded. Enormous quantities of Pacific pomfret, pelagic armorhead, and blue shark were caught (Joint Report -Japan Squid 1991; Joint Report - Taiwan 1991; Joint Report 1990). Very little was kept since neon flying squid could usually be sold for a higher price at the wholesale market. Estimates of the percentage of the total catch that was discarded as spoiled and unwanted by-catch varied between 17% and 55% of the total catch. By agreement with the International North Pacific Fisheries Commission (INPFC) Japan was allowed an incidental catch of salmon, which was not supposed to exceed 15% of the total squid catch. Japan, Taiwan, and the ROK banned the retention of any salmon caught.

Management Although the total number of squid vessels decreased somewhat by the end of the 1980s, the vessels were now generally younger, larger, and more efficient, and fished for longer periods of time. The average amount of driftnet set each night by each vessel increased to over a 1000 tans, and the percentage of Korean and Taiwanese driftnets with a smaller mesh size of less than 100 mm had also increased (Wetherall 1989). In 1980, the average weight of each neon flying squid was 670 grams; in 1983, the average weight was 527 grams; and in 1984, the average was 455 grams. Harvests between 1984 and 1986 decreased, but rebounded somewhat in 1987 (Herrfurth 1988). Although the total squid catch continued to rise gradually, this was accompanied by a much more rapid rise in effort, indicating that the fleet was probably fishing beyond sustainable levels. (Figures 4 and 5)

The North Pacific Large-Mesh Driftnet Fishery

Participants and Target Species The Japanese large-mesh albacore fishery began in the high seas of the North Pacific around 1972. In 1986, the Taiwanese squid fleet began carrying large mesh driftnets to fish for tuna when the price was right (Yeh and Tung 1991). The large mesh fleet targeted primarily albacore (Thunnus alalunga), skipjack tuna (Katsuwonus pelamis), striped marlin (Tetrapturus audax), and broadbill swordfish (Xiphias gladius), but also caught and retained a great number of species of large fish, including mahimahi, amberjack, bigeye tuna, and other billfish. The nets also caught sharks, porpoises, ocean sunfish, leatherback turtles, and whales as by-catch.

Large-Mesh Driftnet Characteristics The large mesh fishery used both monofilament and multifilament nylon nets with a stretch mesh greater than 150 mm. The Japanese commonly used a 170180 mm mesh, with tans 3336 meters long and 810 meters deep. The Taiwanese used a 180210 mm mesh, with tans 3040 meters long and 1021 meters deep (Jones et al 1990). Tans were attached together to form sections and the sections were strung out along a float line 1250 km long, with a space between sections. The Taiwanese tended to fish with two to four very long sections (Joint Report-Taiwan 1990).

Areas and Seasons The large-mesh fleets generally operated slightly south of the main squid grounds (32 - 44 deg N) and occasionally fished as far south as the Exclusive Economic Zones (EEZ) of the Republic of the Marshall Islands and the Commonwealth of the Northern Mariana Islands. The Japanese large-mesh driftnet fleet fished from the coast of Japan to 150 deg W. (Figure 6) Its major fishing season was from January to April, with a smaller amount of effort between July and December. The Taiwanese large-mesh fleet fished mostly between 156 deg and 155 deg W and mainly between June and September, with a smaller amount of effort between April-May and October-December. For the larger by-catch species, such as ocean sunfish, sharks, cetaceans, and turtles, this meant they were threatened with entrapment in large mesh driftnets twelve months out of the year in the North Pacific.

Vessels and Crew In 1973, Japan had an estimated 501 vessels using large mesh driftnets. Many of these were fairly small vessels recruited from coastal fisheries. By 1981, both the number of vessels and average vessel size increased, with a concomitant ability to lay much more net. In 1981, there were 559 Japanese driftnet vessels operating in the North Pacific; in 1983, 620 vessels were in operation; in 1989 the number decreased to approximately 460 vessels. In 1990, the total number, including coastal vessels, numbered 459. Taiwan employed 123138 large-mesh vessels in the North Pacific in 1990, with an international crew of 1722 men.

Operations The nets were set in the early evening and retrieved in the very early morning hours. Setting the net took two to three hours; retrieval took 816 hours, depending on the amount of net set and the weather (Jones et al 1990). In 1989, the total amount of net set each night during peak season was estimated to be 16,000 km (WPRFMC 1989d).

The Catch and By-Catch The main target species were albacore tuna, striped marlin and swordfish. The albacore taken by large-mesh nets in the North Pacific were mostly three to six years of age. In 1980, the Japanese driftnet fleet caught some 6,049 metric tons of tuna in the North Pacific; in 1981, the Japanese catch leaped to 17,585 metric tons. (Table 2) In 1985, the Japanese catch peaked at 20,199 metric tons of albacore. (Table 2) Between 19861989, the Japanese driftnet catch averaged 9,313 metric tons. In 1988, the Taiwanese large mesh driftnet fleet caught 11,366 metric tons of albacore. (Table 2) Juvenile albacore two to three years of age also made up a substantial portion of the by-catch of the squid fleets. Some was kept; most was discarded. It was estimated that some 25,000 metric tons of albacore was caught in 1989 by both the Japanese large mesh and squid driftnet fisheries, including the discards (U.S. Summary 1991). The estimate does not include dropouts.

It should be noted that the official figures released by the Japanese government sometimes varied significantly from unofficial figures or data collected by others. The large mesh by-catch included skipjack tuna, yellowfin tuna, blue marlin, sailfish, spearfish, mahimahi, wahoo, sharks, salmon and pomfret, porpoises, whales, turtles and seabirds, including various species of shearwaters, boobies, petrels and albatrosses.

Management (see The North Pacific Albacore Fishery - A Case History)

The South Pacific Large-Mesh Driftnet Fisheries

Participants and Target Species Taiwan began driftnet fishing for shark, mackerel and longtail tuna in the Arafura and Timor Seas north of Australia in 1974. Australia observers monitored the by-catch of this fishery between 19811983. They recorded several species of small cetaceans being killed and discovered that the by-catch was being under reported by the Taiwanese fishermen. Australia brought the fishery to an end in 1986 by limiting net length to 2.5 km. It has been reported that at least 50 Taiwanese vessels still continue to operate in the Arafura Sea within the Indonesian EEZ.

Between 1982 and 1987, Japanese large-mesh driftnet vessels fished for albacore mainly in the Tasman Sea area of the South Pacific. The Taiwanese large-mesh fleet moved into the Tasman Sea in 1986. In 1987, Japanese and Taiwanese large-mesh fleets began fishing for albacore in the Subtropical Convergence Zone (STCZ) between 30 deg - 40 deg S. A couple of large-mesh driftnet vessels from the Republic of Korea also fished in the South Pacific during the 1980s, but left in June 1989. Since then the ROK has prohibited driftnet fishing in the South Pacific. Japan suspended driftnet operations in the STCZ during the 1990-91 season because of the Wellington Convention and UNGA Resolution 44/225. However, Japan said that it would go back as soon as acceptable conservation and management measures could be implemented. Taiwan continued to driftnet fish for albacore in the STCZ during the 1990-91 season. Beginning in 1989, Taiwanese vessels were also licensed to driftnet in the EEZ of Papua New Guinea (Stewart C. 1990).

Large-Mesh Driftnet Characteristics South Pacific: The driftnets were multifilament nylon with a stretch mesh size of 160200 mm. The width or depth varied between nine and 15 meters. The length of the Japanese large-mesh driftnet varied between 20 and 55 km, although in its last season it ranged between 35 and 80 km (SPF 1991). The average Taiwanese net was around 24 km. During the 198990 season, between 4,500 and 10,000 km of driftnet were set each night in the STCZ.

The Tasman Sea: In 1989, the Japanese used 39 meter long, 10 meter deep tans combined in five km sets, with 50 floats per tan, a double lead line and a 180 mm mesh. Sets were set in parallel rows and approximately 40 km driftnet were fished by each vessel each night (Coffey and Grace 1990). The Taiwanese used 39 m long, 15 meter deep tans, combined in eight km sets with a 200 mm mesh. They also set approximately 40 km of driftnet in parallel rows (Coffey and Grace 1990).

Areas and Seasons The major fishing season was December through April. The fleets fished between 30 - 40 deg S and 140 - 170 deg W in the Sub-tropical Convergence Zone. (Figure 7) Driftnet fishing in the Tasman Sea west of New Zealand was concentrated between 38 - 40 deg S and 162 - 158 deg E. In 1989, Australia and New Zealand banned large-scale driftnet fishing in their EEZs, leaving little of the Tasman Sea available for high seas driftnet fishing. An estimated 20 Japanese and Taiwanese driftnet vessels fished there during the 1989-90 season (Coffey and Grace 1990).

Vessels and Crew In the 198384 season, the Japanese reportedly operated 1720 large mesh driftnet vessels in the South Pacific and Tasman Sea. By 1988-89, the number reached 64. With the passage of the Tarawa Declaration and the Wellington Convention, Japan reduced her fleet in the STCZ to 19 in 198990 and zero in 199091. South Korea withdrew its two vessels in June 1989. During the 1987-88 season, approximately seven Taiwan driftnet vessels were operating in the South Pacific and Tasman Sea. In 1988-89, that number increased to 60-130 vessels. Thereafter, Taiwan announced that only nine vessels would be licensed to fish in the South Pacific STCZ during the 199091 season. However, albacore trollers reported that between 12-18 Taiwanese vessels driftnetted for tuna in the South Pacific in 199091 (Aasted, Vanderpool, pers. comm. 1991). In 1990, one of these was videotaped fishing without a flag. During the 1991-92 season, there were no reports of driftnet fishing vessels operating in the region. Those vessels put out of work by the Wellington Convention presumably moved on to driftnet in the Indian and Atlantic Ocean (Cockcroft 1990). The Taiwanese fleets recruit international crews, mainly indigenous Taiwanese, Filipinos, Chinese, Indonesian, Thai and South Africans.

The Catch and By-Catch In 1984, Talbot Murray of New Zealand's Ministry of Agriculture and Fisheries estimated that Asian driftnet fleets were taking 40,000 metric tons of tuna annually, primarily from the Tasman Sea (Murray 1984). Japanese driftnetters caught 4,271 metric tons of albacore in the South Pacific in 1987-88, 13,263 metric tons in 1988-89, and 5,567 metric tons in 1989-90. (Table 3) Figures on the total Taiwanese catch prior to 1987-88 season are not available. It was estimated that Taiwanese driftnetters took approximately 11,000 metric tons each season during 1987-88 and 1988-89. Korea took 184 metric tons in 1988-89. (Table 3) The decrease in 1989-90 catch was primarily due to a reduction in driftnet fleet size, as a result of pressure from the South Pacific States. FAO (1990) estimates that the entire large mesh driftnet fishery could have taken up to 49,000 metric tons of albacore out of the South Pacific during 1989. (See also SPF 1991; Wright and Doulman 1991.)

The South Pacific by-catch included billfish, sharks, marine mammals, and ocean sunfish. Exact quantities are not known, but are likely to be substantial and probably similar to other large mesh pelagic fisheries. Particular species reported taken as by-catch include skipjack tuna, broadbill swordfish, striped marlin, shortbill spearfish, oceanic whitetip shark, mako shark, blue shark, ocean sunfish, common dolphin, southern bottlenose whale, and an assortment of other species.

Estimates of the Tasman Sea catch and by-catch taken by 20 vessels fishing 40 km of driftnet per night during 1989-90 season include 780,000 - 900,000 tunas, 3,000 ocean sunfish, 3,000 billfish, 4,000 sharks, 6,400 dolphins, and 20,800 ray's breams (Coffey and Grace 1990).

Management Albacore targeted by large-mesh driftnets in the South Pacific were two year old, pre-reproductive juveniles (Murray 1989). Albacore begin to reproduce when they are about five years old. Scientists have suggested a maximum sustainable yield (MSY) for the South Pacific albacore surface fishery, trolling and driftnet, of 10,000 metric tons (Murray 1984). In 1988-89, the driftnet catch totaled 24,447 metric tons, grossly exceeding the suggested MSY. The New Zealand and U.S. trolling fleets took 8,902 metric tons. The total estimated albacore catch for the 1989-90 season was 15,578 metric tons, with approximately 8,902 metric tons taken by the trolling fleets. A dropout rate of up to 40% of the catch has been estimated (UN Secretary-General's Report, 1990). The amount of albacore that was discarded due to putrefication is unknown. Wastage estimates vary between 400012,000 metric tons, based on estimated dropout percentages.

By June of 1991, the economies of the South Pacific States began to suffer the effects of the three years of massive driftnet fishing effort by the Asian driftnet fleets. The past removal of huge quantities of young albacore from surface waters by large-scale driftnets was causing falling numbers of adult albacore. The FFA concluded that previous estimates of the amount of tuna removed were probably too low, both because the distant water fishing nations did not provide accurate information and because the figures did not include those albacore that escaped the nets, but died as a result of their encounter (World Fishing 1991).

The North Pacific Salmon Driftnet Fisheries

Introduction Customary international law (Footnote 1), as evidenced by the United Nations Convention on the Law of the Sea (UNCLOS), provides that "[s]tates in whose rivers anadromous stocks originate shall have the primary interest in and responsibility for such stocks." (Article 66 (1)) UNCLOS also provides that "[f]isheries for anadromous stocks shall be conducted only in waters landward of the outer limits of exclusive economic zones, except in cases where this provision would result in economic dislocation for a State other that the State of origin." (Article 66(1)(a)) In recognition of Japan's traditional reliance on salmon fishing, the International North Pacific Fisheries Commission (INPFC) reduced and restricted the areas that Japanese salmon driftnet vessels could fish gradually.

The North Pacific Salmon stocks are currently managed by the North Pacific Anadromous Fish Commission (NPAFC), established by the Convention for the Conservation of Anadromous Stocks, which came into force on 16 February 1993, and which replaced the International North Pacific Fisheries Commission. On 11 February 1992, Canada, Japan, the Russian Federation, and the United States signed the Moscow Convention for the Conservation of Anadromous Stocks in the North Pacific Ocean. The Convention prohibits "directed fishing for anadromous fish", including through the use of large-scale driftnets in the waters of the North Pacific Ocean and its adjacent seas, north of 33 deg N beyond the 200-mile limits of the signatory states (Article III). The Convention provided for the establishment of the North Pacific Anadromous Fish Commission, whose mandate is to promote the conservation of Pacific anadromous species throughout their migratory range in the high seas area of the North Pacific Ocean and its adjacent seas, as well as the conservation of ecologically-related species, including marine mammals, sea birds and non-anadromous fish.

Target Species There are six North American salmon species: pink (Oncorhynchus gorbuscha), coho (O. kisutchy), chinook (O. tshawytscha), sockeye (O. nerka), chum (O. keta) and steelhead (O. mykiss) and an unknown number of Asian species that originate in the rivers of the former Soviet Union, the Peoples Republic of China and Japan. All of these species mature in the high seas of the North Pacific and all were caught, directly or indirectly, by salmon and squid driftnet vessels. Many of these salmon owe their existence to fish hatchery programs financed by their States of origin.

Participants After World War II two Japanese salmon driftnet fisheries, using monofilament nylon net, began operating in the North Pacific: a mothership fishery that began in the Bering Sea in 1952 and a landbased fishery that operated south and west of the Aleutian Islands. They were regulated by the International North Pacific Fisheries Commission (INPFC), established to implement the provisions of the 1952 International Convention for the High Seas Fisheries of the North Pacific Ocean (North Pacific Convention). The Convention was enacted by Canada, Japan, and the United States to: "1) ensure cooperation in scientific research and data collection on salmon and other fish species in the North Pacific Ocean and Bering Sea; 2) minimize interceptions of North American origin salmon by Japan; and 3) facilitate cooperation in marine mammal research" (Beasley 1984). Each party agreed to enact and enforce the necessary domestic laws and regulations to implement the Convention provisions (North Pacific Convention, Article 9(2); 16 U.S.C. Sections 10211035). The North Pacific Convention was renegotiated in 1978 and again in 1985. New amendments increasingly restricted the salmon driftnet fishing boundaries and delineated scientific data collection programs and enforcement efforts.

Japan also concluded a treaty with the Soviet Union which regulated Japanese salmon driftnet vessels fishing on Soviet stocks beyond the Soviet EEZ (Japan-U.S.S.R. Fisheries Convention 1956). In 1985, the Agreement on Fishery Cooperation established the Japan-U.S.S.R. Joint Fishery Commission, In April 1990, the Commission negotiated an agreement which permitted the Japanese salmon driftnet fleet to catch 11,000 metric tons of Soviet salmon on the high seas of the western North Pacific. Nets were limited to 1015 km in length, depending on vessel size, a minimum distance between sets was established, and mesh size was restricted to 5565 mm, depending on the vessel's size (UN Secretary General's Report 1990). One month later the Soviets caught 12 unauthorized Japanese-owned squid driftnet vessels flying North Korean flags fishing for Soviet salmon in this zone (see The Enforcement Problem).

Salmon Driftnet Characteristics Salmon driftnet is monofilament nylon with a stretch mesh between 75 and 100 mm for the landbased fishery and 121-130 mm for the mothership fishery. The nets are approximately eight meters deep. By regulation length is limited to 15 kilometers.

Areas and Seasons In the Annex to the 1952 North Pacific Convention, Japan agreed to abstain from fishing for salmon east of 175 deg W in both the North Pacific Ocean and the Bering Sea, and Canada agreed to abstain east of that line in the Bering Sea. However, studies conducted by the United States beginning in 1956 soon indicated that western Alaska salmon were migrating west of 175 deg W. In 1978, the North Pacific Convention was renegotiated. The 1978 amendments shifted the line to 175 deg E, except for a small area of high seas in the Bering Sea called the "donut hole". (North Pacific Convention Protocol 1978). Following further study, the North Pacific Convention was amended again in 1988. After 1988, no mothership salmon fishing was permitted in the Bering Sea east of 180 deg; after 1993, the mothership fishery could not fish at all in the Bering Sea. The agreement also called for continent-of-origin studies and further negotiations in 1991. East of 170 deg E the Japanese landbased fleet was limited to an area south of 46 deg N; west of 170 deg E the fleet could fish south of 48 deg N. No Japanese landbased vessels could fish for salmon east of 174 deg E (Amended Annex). A map of the areas and times salmon driftnet fishing could take place is shown in Figure 8. A map of the known distribution of North American steelhead is shown in Figure 9.

Vessels and Crew The Bering Sea mothership fishery began in 1952 with three motherships and fifty-seven catcher boats (Sathre 1986). In 1959, the fleet peaked with 16 motherships and 460 catcher boats. In 1978, the fleet was reduced by the INPFC to four motherships and 172 catcher boats. Those vessels put out of work by the agreements moved south to start up the North Pacific high seas squid driftnet fishery. By 1991, the salmon mothership fishery had converted to a landbased fishery.

The landbased salmon driftnet fleet operated on the high seas of the North Pacific south and west of the Aleutian Islands and delivered its catch directly to Japan. By the mid 1980s, this fleet had 210 vessels; in 1991 it employed 109 vessels with less than 127 GRT.

The Catch and By-Catch In 1980, the mothership fleet took a record 703,798 chinook salmon. Since that time annual quotas have been negotiated between Japan and the countries of origin. In 1990, the legal catch of North American salmon taken by the Japanese landbased salmon driftnet fishery was 10,000 metric tons. The Soviets also permitted another 10,000 metric tons of Soviet salmon to be caught by the Japanese. The illegal catch of North American salmon was estimated at 30,000 metric tons. By agreement, the squid fishery was permitted an incidental catch of salmon, as long as it did not amount to more than 15% of its total squid catch. Dall's porpoise and several species of seabirds were commonly caught as by-catch by the salmon driftnet fisheries. (Table 5, Dall's porpoise; Table 6, seabirds)

Management Fishing for salmon on the high seas did not and does not make much sense from a stock management/sustainable fishery point of view. The high seas driftnet fleets harvested salmon before they could reach maturity and maximum weight, and therefore did not maximize the stocks' optimum sustainable yield; the various salmon stocks mingle on the high seas making it impossible for the high seas driftnet fisheries to manage individual stocks; up to fifty percent of the salmon caught dropped out of the nets before they could be brought on board (Campbell 1985), and driftnets lost or discarded at sea continued to entrap salmon (Sathre 1986).

The Indian Ocean Large-Mesh Driftnet Fishery

Participants, Target Species and Vessels In 1984-85, the Taiwanese began using large scale driftnets to fish for albacore in the south Indian Ocean. Estimates of the number of driftnet vessels operating in that year vary between 36 and 92. In 1987-88, a total of 130 driftnet vessels were reported operating (UN Secretary-General's Report 1990). In 1989-90, an estimated 139 Taiwanese vessels were in operation; in 1990-91, approximately 113 vessels were operating. During 1991-92, 31 Taiwanese large-mesh driftnet vessels were officially permitted to operate in the Indian Ocean (Fisheries Division, Taiwan Council of Agriculture).

Japan reportedly took steps to prohibit large scale driftnet operations by its nationals in the Indian Ocean. However, Japanese nationals reportedly have or had investment interests in Taiwanese driftnet operations. Tuna caught by the driftnet vessel Yu Chan Sar was off-loaded at the warehouse of Kaigai Gyogyo Kabushiki Kaisha (KGKK), a wholly owned subsidiary of the Mitsubishi corporation. In 1991 KGKK held the controlling interest in Mauritius Tuna Fishing and Canning Enterprises and may still be an owner. Port Louis, Mauritius, is a major base for Taiwanese driftnet vessels fishing in the Indian Ocean. Much of the fishing port and cargo dock of Port Louis was funded with Japanese capital (Davis 1991). There were also reports that Japan sold some of its older driftnet vessels to Taiwanese businessmen.

Driftnet Characteristics Multifilament nets with a mesh size between 200-220 mm are used, with a depth of 45-47 m. Fifty meter tans are strung into lengths between 37-47 km (Northridge unpub).

Areas and Seasons The large-scale driftnet fishing season occurs in the southern Indian Ocean between October and February. In the 1986-87 and 1987-88 seasons, Taiwan fished between 25 - 45 deg S and 35 - 115 deg E. Between December and January the fleet fished between 70 - 100 deg E, then moved west and by March and April fished at 30 deg E (Hsu and Liu 1990). (Figure 10)

The Catch and By-Catch Records showed that in 1986-87, 30% of the Indian Ocean catch were sharks and only 10% were tunas and billfishes (UN Secretary-General's Report 1990). No data was kept on the incidental take of marine mammals. The UN Secretary-General (1990) reported that the total catch of albacore from the southern Indian Ocean, driftnets and long-lines combined, was about 25,000 tons in 1987 and 22,000 tons in 1988. The UN Secretary-General (1990) reported that an additional 90,000 metric tons of tunas, seerfishes and billfishes were caught in Indian Ocean EEZs in 1988 by coastal States using driftnets 1.510 km in length. However, the Forum Fisheries Agency (FFA) reported that the 1987 total Indian Ocean tuna catch from all sources was 642,000 metric tons (FFA News Digest 1991). Taiwan's tuna catch is usually transferred to carrier boats and sent to cold storage in Singapore and canneries in Thailand. The world wide drop in tuna prices in 1990 due to a glut of low quality driftnet tuna reportedly kept the carrier boats from going to the Indian Ocean in 1990-91 season and Taiwan had to bring its catch home (Perkins pers. comm. 1991).

Indian ocean by-catch includes yellowfin, bigeye, southern bluefin, skipjack, striped marlin and swordfish. By-catches of marine mammals, sharks, ocean sunfish, turtles, seabirds, and other fish taken as by-catch were generally unreported. In April 1991, five Filipino crew members of the Yu Chan Sar disembarked at Port Louis, Mauritius, after driftnet fishing for three months in the Indian Ocean. They were suffering from injuries due to frost bite and beatings. They reported that they had trapped between 50 and 100 sperm whales, hundreds of dolphins and hundreds of sea lions (EII 1991). The whales and dolphins were cut out of the nets and left to the sharks. The genitalia from male sea lions was cut off to be sold in Taiwan. The rest of the sea lion was thrown back into the ocean (Sea Shepherd 1991).

Management Scientists have assessed the MSY of albacore for all albacore fisheries in the southern Indian Ocean at between 19,000 and 25,000 tons. In view of the limited amount of data on catch and by-catch provided by the fishery participants, the Committee on the Management of Indian Ocean Tuna of the Indian Ocean Fishery Commission (IOFC) in 1990, recommended that the 30 June 1992 UN moratorium should go into effect for the Indian Ocean until effective conservation and management measures could be taken based upon statistically sound analysis to be jointly made by all concerned parties (UN Secretary General's Report 1990). The committee also recommended that observers be placed on board all vessels using large scale driftnets.

The Atlantic Ocean Driftnet Fisheries

The North Atlantic

In 1991, France, Ireland, the United Kingdom, and Norway were reported driftnet fishing for albacore tuna in the Northeast Atlantic. The large-mesh driftnets used by Cornish (UK) driftnetters 300 miles west of Land's End and 200 miles southwest of Ireland were monofilament, 17 meters deep, and 56 kilometers long. Bait boats, trolling vessels and longliners have traditionally fished in this area for tuna. The yield varied between 30,000 and 60,000 tons. By-catch of dolphins was conservatively estimated at 0.3 dolphins per trip.

There are two main driftnet fisheries operated by Irish vessels off the coast of Ireland. Ireland began an experimental driftnet fishery for albacore in the northeast Atlantic in 1990, using multifilament nets; by 1992, six driftnet vessels were operating. Ireland also has an inshore salmon driftnet fleet that fishes illegally and threatens the existence of the salmon stocks in both Ireland and Scotland. In 1988, there were an estimated 60 illegal boats, each using three to four miles of gillnets and transhipping their illegal catch to legal boats for landing. It has been estimated that 500,000 salmon were illegally caught in 1988. Ireland is a member of the North Atlantic Salmon Conservation Organization.

The French began operating a large-mesh albacore driftnet fishery in 1986; in 1989, 37 vessels participated; in 1992, 50 vessels were driftnet fishing. The vessels ranged in length from 18 to 25 meters and were crewed by seven to eight men. Their carrying capacities ranged from 15-25 metric tons. During the 3 1/2 month fishing season between May and September, the French driftnet fleet fished north of the Azores outside the EEZs of Spain and Portugal in May and June and moved north, outside the EEZ of Spain in July, southwest of Ireland in August and in the Gascogne Gulf (Bay of Biscay) inside France and Spain's EEZs in September. (Figure 11) Fishing trips were 15 to 25 days in duration, depending on the distance between ports and the fishing grounds. On average, a vessel made five or six trips during the season. On average, ten sets were made per trip. French nets are red, multifilament nylon with a 170-180 mm stretched mesh, 1522 meters deep, and (prior to 1 June 1992) 57.5 km in length (100-150 tans, each measuring 50 m in length). A few nets are set with a "surface gap" (cork line submerged down two meters).

The French claim that their incidental catch of birds and mammals has been "negligible" (FAO 1990, para 4d), although fishermen and observers report takings of common dolphin, striped dolphin, and bottlenose dolphin (Bonnemains and Kanas 1990). The French averaged 1.5 dolphins caught per trip, resulting in estimates of an annual by-catch of between 2,00010,000 dolphins caught by French driftnets. In 1990, the fleet caught 1,600 metric tons of albacore tuna, 200 tons of bluefin tuna and swordfish, 200 tons of Ray's bream (swallow fish) and at least 200 tons of blue shark. The blue shark were thrown away. During the 1992 season, 4,000 metric tons of albacore were caught. Albacore and other tunas reportedly comprised 86 percent of the catch. By-catch included wreckfish, swordfish, shortfin mako shark, blue shark, Atlantic pomfret, cetaceans (mostly striped and common dolphins), turtles, and birds (Tuna Newsletter 1993).

In November 1991, the European Parliament adopted a resolution calling for a ban on imports and sale of tuna caught by purse seines that set on dolphins or driftnets that exceed a cumulative length of 2.5 km and a requirement that documentary evidence certified by an authority officially recognized by the European Commission be provided to establish that tuna offered for trade were not caught by the prohibited methods. The European Parliament also passed Resolution B3-1791/93 that proposed a total ban on the use of driftnets outside the 12-mile zone and permitted the use of driftnets within 12 miles "on the basis of rules drawn up for each individual case." However, EC Fisheries policy implementation and enforcement by member States is uneven. Several, but not all, member States have passed legislation implementing the UN driftnet resolutions. The excess capacity of the fleets encourages under-reporting and heavy political pressure to increase fishing quotas beyond optimum sustainable yields. Port inspections are adequate in only a few states, such as the Netherlands and Germany (World Fishing 1993). Surveillance on the high seas and in the EEZs of member states is almost non existent. The EC member states badly need to coordinate and improve their enforcement efforts and to initiate a buy-back program to get their fishing fleets down to levels that are in balance with their fishing resources.

The Mediterranean

The Mediterranean high seas begins 6 to 12 miles off the coast of most of the bordering States. Large scale driftnetting has been conducted in the Central Mediterranean by Italian fishermen (Di Natale and Notarbartolo-di-Sciara 1990). More than 700 boats fished for an annual catch of 5000 tons of swordfish and 1000 tons of albacore using nets from 2 to 40 km, with an average of 12 km. The by-catch included medium and large fish, turtles, and small and large cetaceans, including harbor porpoise, common, striped and bottlenose dolphins, pilot whales and sperm whales. In the late 1980s, large numbers of dead and mutilated dolphins began appearing off Italian beaches and the fleet was suspected of grossly under reporting the by-catch. The fleet claimed only 100 mammals were taken in 1988 (UN Secretary General's Report 1990). In 1989, 30 to 40 Spanish vessels were also reported using driftnets in the Mediterranean. Other States that driftnetted in the Mediterranean included France, Greece, Algeria, Malta, Morocco, and Turkey (Di Natale and Notarbartolo-di-Sciara 1990). It was estimated that by 1990 more than 10,000 km of driftnet were being used in the Mediterranean with a resultant by-catch of 7,00010,000 dolphins, 2,300 sperm whales and tens of thousands of seabirds (Sea Shepherd Conservation Society 1991). In 1990, the Italian government suspended all driftnet fishing for swordfish and albacore. However, in 1991, intense lobbying by the fishermen resulted in a resumption of large scale driftnet fishing near Greece and Corsica by Italian and Sicilian vessels. According to figures supplied by the Italian Merchant Marine Ministry, in 1990-91, only 18 percent of the Italian driftnet catch was swordfish; the other 82 percent consisted of some 85 species, almost all of which were discarded. The discards included Atlantic bonito and frigate mackerel, which are principal target species of other Mediterranean fisheries, as well as juvenile bluefin tuna.

In September 1992, experts at the second GFCM/ICCAT Expert Consultation on Stocks of Large Pelagic Fishes in the Mediterranean Sea, held at Crete, Greece, reported that driftnets were still widely used in the Ligurian Sea and around Sardinia, and that several vessels were deploying driftnets in excess of 2.5 km in length in the Mediterranean (UN Secretary-General's Report 1993). They also reported that two French driftnet vessels were fishing with nets about 3 km in length, but that Italy was the principal driftnet user in the Mediterranean. During 1992-93, despite EC regulation 345/92 prohibiting driftnet fishing with nets more than 2.5 km in length, it was estimated that some 720 Italian fishing vessels were fishing for swordfish in both the territorial and international waters of the Mediterranean using driftnets averaging 10 km in length, with some as long as 15-20 km. In addition, some ten percent of the Spanish driftnet vessels fish in the Mediterranean around Gibraltar; the rest fish in the Atlantic. Driftnets have also been reported in Tunisian and Turkish waters, although the Tunisian government does not permit its fishing fleet to use large-scale driftnets (UN Secretary-General's Report 1993).

The General Fisheries Council for the Mediterranean (GFCM) has expressed concern that joint venture arrangements between some European and some North African fishermen are causing the transfer of large-scale pelagic driftnetting from the northwest Mediterranean to the southern Mediterranean. Experts at the second GFCM/ICCAT Consultation noted that some vessels had changed flags to circumvent EEC regulation 245/92 (UN Secretary-General's Report 1993).

The Central Atlantic

In February 1990, Taiwan announced a ban on the operation of the Taiwanese driftnet fleet in the Atlantic west of 20 deg E. However,there was a growing suspicion that some of the large-mesh tuna driftnet vessels phased out of the South Pacific in 1989 were moving west into the Atlantic in violation of UNGA Resolution 44/225. ( UNGA 44/225 called for an "immediate cessation of further expansion of large-scale pelagic driftnet fishing on . . . all the other high seas outside the Pacific ocean.").This was soon born out. In August 1990,Sid Johnson,of the Trinidad & Tobago Game Fishing Assoc photographed six Taiwanese driftnet vessels refueling in Port of Spain, Trinidad and Tobago. Taiwanese driftnet vessels were also reported operating in the western Central Atlantic. Reportedly Uruguay was being used by Taiwanese driftnetters for refueling and transshipping their catch.

Japan announced that it took measures, effective 15 August 1990, to prohibit Japanese large scale driftnet fishing in the Atlantic (UN Secretary General's Report 1990). No Japanese boats were reported in the area. In 1992, Namibia reported that it now prohibits not only the use, but the possession of driftnets in its EEZ (UN Secretary-General's Report 1992) In 1992, Trinidad and Tobago reported that it had banned the servicing of any vessels involved in large-scale driftnet fishing.

The South Atlantic

In 1987, 77 Taiwanese squid driftnetters were operating in the southwestern Atlantic, 30 of whom were given permission to fish in the Falkland's EEZ under a Sino-British Falklands Fishery Cooperation Agreement. Taiwan reported that its 1987 squid catch exceeded 120,000 metric tons (Council of Agriculture 1988). The Japanese were also reported to be driftnet fishing for squid around the Falklands (Herrfurth 1988).

In 1989, 167 vessels carrying driftnets (153 Taiwanese, 13 Japanese, 1 ROK) were given permission to call at South African ports en route to the South Atlantic to fish for squid (Rice in press; Cockcroft 1990). In 1990, 166 vessels from Japan, Taiwan, and the Republic of Korea were given permits to enter South African ports with driftnets on board. Only five of these vessels had been given licenses to fish in the Falklands 150 mile Fishery Conservation Zone (FCZ) (Krohn 1990). While some of these vessels may have been heading for the Indian Ocean, a South African research vessel caught its propeller in a driftnet in the waters around Tristan da Cunha where it saw five vessels driftnet fishing (Northridge unpub). A South African crew member of a Taiwanese vessel reported that driftnet vessels en route to fish for squid in the Falklands Islands usually spent at least a month driftnetting for albacore (Krohn 1990). He reported a by-catch for the vessel he was on that included 1520 dolphins, 34 whales, ocean sunfish, sharks and other fish.

In 1990, a 389 GRT Taiwanese vessel, the An-Hung 1, ran aground near Cape Town, South Africa with 145 km of driftnets on board, 65 km of which later washed overboard. The mesh size was 300400 mm; nets were 20 meters deep (Cockcroft 1990). The vessel's hold was filled with tuna and more than 50 rockhopper penguins of a subspecies that breeds at Tristan da Cunha and Gough Island. Ryan and Cooper (1990) also reported that five Asian driftnet vessels were seen fishing near Tristan da Cunha and Gough Island, and other driftnet vessels were seen fishing further south (Krohn 1990). Krohn (1990) notes that in addition to the five mentioned above, 123 other vessels were licensed to fish in the Falklands FCZ in 1990. There is a high probability that some, perhaps most of these vessels, were also driftnetting for tuna en route. If so, a huge, unrecorded by-catch was taken out of the South Atlantic each year.

The Taiwanese government announced that it was banning driftnet fishing in the Atlantic on 16 February 1990 to comply in principle with UN resolution 44/225 (World Fishing 1991). On 28 November 1990, Argentina, the Falkland Islands and the United Kingdom announced that they were expanding the eastern half of the Falklands 150 mile EEZ to 200 miles to protect fishing resources in that area. The three States imposed a complete commercial fishing ban in the area to protect illex squid stocks. Up to 200 vessels, mostly belonging to Japan, ROK and Taiwan, fished in the area (World Fishing 1990).

In 1987-1989, 131,632 frozen tuna were offloaded in Cape Town, South Africa, a 51% increase over the year before. There was also a concomitant increase in landings of angel fish, a fish commonly recorded as by-catch in driftnets (Krohn 1990). While these fish may have originated in the Indian Ocean, the tuna driftnet fleet there concentrates its efforts between 70 deg E and 100 deg E, a long way from Cape Town (Figure 10). The Taiwanese fleet usually transfers its Indian Ocean catch to carrier boats from Singapore where the tuna is offloaded. As stated previously, in 1990, there were reports that the carrier boats did not go to the Indian Ocean and the Taiwanese driftnet fleet transported its Indian Ocean catch back to Taiwan (Perkins pers. comm. 1991).

In February 1993, the South African government gave Taiwanese driftnet vessels permission to enter Cape Town harbor for inspection purposes. The Taiwanese government representative gave assurances at that time that any driftnet equipment that had not been removed would be removed as soon as possible. In July 1993, inspections of two distinct groups of Taiwanese fishing vessels returning from fishing in the South Atlantic revealed the following: in the first group of 23 vessels, 13 still had driftnet equipment on board, some had registration numbers that also appeared to be on vessels of another name, several had incomplete or no name on the stern or a names that appeared painted over, one vessel had no name painted on either the bow or the stern, and one vessel appeared to have been operating under two names. In the second group of 30 vessels, 14 still had driftnet equipment on board and 10 had no name or the name only partially painted names (Dolphin Action & Protection Group 1993).

On 20 March 1993, a Panamanian-registered fishing vessel, the Martins Mar, was observed blanketing the Vema seamount with large-scale gillnets some 8 km in length. The Vema seamount is situated some 500 miles west of the South African coast. The Martins Mar was based in Peniche, Portugal and its captain and owner was a Portuguese citizen and a Portuguese resident. Some nets were apparently left in place for three days before hauling and much netting was later abandoned on the seamount. A South African fishing vessel recovered hundreds of meters of net floating above the seamount. The recovered nets contained more than three tons of rotting fish. The crew said there was much more net that could not be recovered because it could not be lifted from the water.

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