by Kevern Cochrane *
INTRODUCTION
This section on the Southeast Atlantic deals with the waters adjacent to the coastlines of Angola, Namibia and South Africa and extends well into the high seas to the south and west (Figure B7.1). The islands of St Helena, Ascension and Tristan da Cuhna also fall within this area. Nominal catches made by South Africa in the western Indian Ocean are included in Area 47. However, except for those from the Agulhas Bank, which is considered a part of the Benguela upwelling system, these catches form a very small part of the total for the region. The rest of the region is dominated by the Benguela upwelling system which supports relatively high production along much of the coastline of these three countries. The northern border of the Benguela upwelling system occurs at the thermal front with the warm Angola Current, normally between about 15°S and 17°S on the coastal shelf in southern Angola. North of the Angolan front, most of the coastal shelf of Angola is dominated by the southward flowing and less productive Angola Current. The Benguela ecosystem is sub-divided into the northern Benguela and the southern Benguela, separated by the partial barrier of a very intense upwelling cell off the town of Lüderitz, some 300km north of the border between Namibia and South Africa. The region covers a total surface area of about 18.4 million km2, with less than 0.5 million km2being shelf area.
Figure B7.1 - The Southeast Atlantic (Area 47)
There was substantial environmental variability in the region during the 1990s, and this undoubtedly influenced the dynamics of several important fish stocks. In the northern Benguela, the unusually widespread occurrence of deoxygenated water in 1993 and 1994 was an important environmental event. It resulted in oxygen concentrations as low as 0.25 ml per litre over much of the northern half of the Namibian shelf, extending beyond 50 nautical miles offshore. In normal years, such low oxygen concentrations occur only over about one third of this area. In addition, in the first half of 1995, unusually warm conditions with reduced upwelling, a Benguela Niño, occurred over northern and central Namibia as well as in southern and central Angola. By the end of 1995 conditions had cooled to more normal temperatures (Namibia Foundation, 1998). The southern Benguela system experienced an unusual sequence of a short period of intense warming in December 1999, followed rapidly by a period of strong cooling early in 2000. This sequence was associated with record recruitment to the local anchovy stock, although any causal link is not well understood.
Figure B7.2 - Annual nominal catches ('000t) by ISSCAAP species groups in the Southeast Atlantic (Area 47)
Source FAO
PROFILE OF CATCHES
Total nominal catches from the Southeast Atlantic increased from less than 0.5 million tonnes in 1950 to slightly over 3 million tonnes in 1968 (Figure B7.2 and Table D7). Catches remained high, although irregular and declining, until the late 1980s and then decreased abruptly from 2.8 million tonnes in 1987 to 1.3 million tonnes in 1991, driven partly by a large decline in anchovy catches and policy changes in Namibia after it gained independence in 1990. They have remained under 2 million tonnes since then, with an average catch of approximately 1.65 million tonnes between 2000 and 2002. Catches from the region are dominated by ISSCAAP Groups 35 - herring, sardine and anchovies, 37 - miscellaneous pelagic fishes (including horse mackerel), and 32 - cods, hakes and haddocks (Figure B7.2). The most important stocks within these groups were all subjected to heavy fishing pressure at different periods between the 1960s and the 1980s, leading in some cases to quite severe declines in abundance that were reflected in declining catches. The position was stabilized in many of these cases by imposition of more rigorous management regimes.
The small pelagic fisheries of the region, which together account for the highest proportion by mass of the catches, are dominated by six taxonomic groups: South African pilchard (Sardinops sagax ) (also still referred to as S.ocellatus ), South African anchovy (Engraulis capensis ), sardinellas (round Sardinella aurita and madeiran or flat S. maderensis ), Whitehead's round herring (Etrumeus whiteheadi ), Cape horse mackerel (Trachurus capensis )and Cunene horse mackerel (T. trecae ). In 2001, Cape horse mackerel accounted for the largest catches of small pelagics, followed by South African pilchard and anchovy and then, substantially lower, the sardinellas and Whitehead's round herring (Figures B7.3 and B7.4).
Cape horse mackerel is caught mainly in Namibia, and in Angola it is gradually replaced in catches by the Cunene horse mackerel as one moves further north. Catches of the two horse mackerel species have declined since the late 1970s and mid-1980s. In the case of the Cape horse mackerel this was probably caused by the effects of heavy exploitation, particularly in Namibia in the late 1970s and early 1980s. In both species, heavy exploitation in the late 1970s and 1980s was followed by a large reduction in fishing mortality when the then USSR fleet was drastically reduced after 1989, and the lower catches also reflect this reduced effort. Recorded catches of Cape horse mackerel were 354 000t in 2001, the lowest since the mid-1970s, and increased slightly to 386 000t in 2002. Catches of Cunene horse mackerel were under 47 000t in 2001 and 2002, also low in relation to typical catches of the last two decades.
Figure B7.3 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 35, Southeast Atlantic (Area 47)
Source FAO
Figure B7.4 - Annual nominal catches ('000t) of selected species in ISSCAAP groups 32 & 37, Southeast Atlantic (Area 47)
Source FAO
South African anchovy and pilchard are both managed in South Africa through total allowable catches (TACs) set each year on the basis of estimated biomasses of the stocks. Catches of South African anchovy have increased steadily since falling to a minimum of 42 000t in 1996, reaching 289 000t in 2001 and decreasing to 255 000t in 2002 (Figure B7.3). Catches of South African pilchard were 265 000t in 2002, the highest recorded since 1976. Catches of Whitehead's round herring fluctuated without meaningful trend from the early 1980s, with a small peak in the mid-1990s and the maximum of 97 000t recorded in 1997. Since then, catches have been between 56000 and 64 000t, apart from in 2000 when they fell below 40 000t (Figure B7.3). The higher catches in 1995 (79 000t) and 1997 (97 000t) were probably, at least in part, a result of fishing effort being diverted to round herring from the struggling anchovy fishery, as the former is not regulated by a TAC in South Africa at present.
Figure B7.5 - Annual nominal catches ('000t) of selected species in ISSCAAP group 34, Southeast Atlantic (Area 47)
Source FAO
Figure B7.6 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 33, Southeast Atlantic (Area 47)
Source FAO
North of the Benguela front, primarily in Angolan waters, sardinellas become the dominant clupeoid in catches. In recent years there has been a shift in relative abundance of the two sardinella species and since 1994 the flat sardinella has tended to dominate in surveys (Bianchi, 1999). Catches of the two species combined peaked at 286 000t in 1977. After 1989, following a substantial reduction in fishing effort in the region as a result of political changes in the then USSR, catches declined and were well under 100 000t during the 1990s (Figure B7.3). They increased to 114 000t in 2000 but fell again to under 30 000t in 2002.
The taxonomic groups most important in the demersal fisheries of the region include the shallow water (Merluccius capensis) and deepwater(M. paradoxus) Cape hakes, Devil anglerfish or Cape monkfish (Lophius vomerinus ), snoek (Thyrsites atun ), which is also taken by handline, and also dentex, including Angolan (Dentex angolensis) and especially large-eyed dentex (D. macrophthalmus ), which is important in Angola (Figures B7.4, B7.5 and B7.6). Of these, the Cape hakes accounted for the highest catches, remaining fairly constant under TAC management at between 260 000 and 323 000t since 1995. Catches of snoek have been under 20 000t since 1992, with some evidence of a possible decline over this period. Catches of unidentified dentex remained fairly consistently above 10 000t from the early 1950s through to 1968 when they started to decline. They fell below 1 000t in 1980, and remained below this mass until 1993, which year marked the start of a recovery leading to catches of over 16 000t in 2001 and of 9 000t in 2002. Significant dentex catches are also recorded under the heading of large-eyed dentex, and these have ranged from 40t in 1994 to a maximum of 43 200t in 1976. Catches of 237t of large-eyed dentex were recorded in 2002.
In addition to the fish species of particular commercial importance described above, a number of members of ISSCAAP Group 33 Miscellaneous coastal fishes contribute to important fisheries in the region (Figure B7.6). The largest catches within this group, apart from dentex which also falls within Group 33, were of West African croakers nei (Pseudotolithus spp.), which are caught mainly by Angola. Catches in 2002 were approximately 26 000t, the highest on record, continuing a period of relatively high catches that started in 1998 when they increased from under 2 000t the previous year to over 7 000t. From 1990 to 2002, the following groups generated catches that averaged more than 1 000t per year: Croakers, drums nei (Sciaenidae : average 3 285t); Porgies, seabreams nei (Sparidae : average 2 937t); Panga seabream (Pterogymnus laniarius : average 2 513t); Gobies nei (Gobiidae : average 2 460t); Mild (Southern) meagre, known locally as kabeljou or kob (Argysomus inodorus previously A.hololepidotus: average 1 430t); Groupers, seabasses nei (Serranidae: 1 245t); Pargo seabreams nei (Pagrus spp.: 1 167t); and Canary drum (Baardman, Umbrina canariensis : average 1 017t). Bigeye grunt (Brachydeuterus auritus: average: 959t); Sand (locally “white”) steenbras (Lithognathus mormyrus: 923t); Mullets nei (Mugilidae: average: 887t); Threadfins, tasselfishes nei (Polynemidae: 806t); Grunts sweetlips nei (Haemulidae: 707t); Sea catfishes nei (Ariidae: 552t); and Red Pandora (Pagellus bellottii : 535t) yielded averages between 500 and 1 000t over the same period.
Namibia currently accounts for most of the catches of the Porgies and seabreams nei (Sparidae). Catches of this group peaked at over 61 000t in 1966 but soon dropped and have not been above 12 000t since 1970. Catches have been under 1 000t since 2000. Southern meagre is landed mainly by Angola. The 2001 catches of over 3 700t were the highest on record. On the other hand, the 2002 catches of 611t were the lowest on record since 1976. Angola is also the major coastal state landing Croakers, drums nei while the Republic of Korea takes the largest portion of catches of the group. Catches of this group have fluctuated between over 750t and a maximum of 6 300t since 1950. The relatively high average catches of Gobies is misleading and, apart from very high catches of 21 000t of Gobies by Namibia in 1998, catches of the group are generally well under 500t per annum. Sand steenbras and Bigeye grunt are fished mainly by Angola. The highest catches of Sand steenbras of 2 800t were taken in 2002, but catches are more usually below 1 000t.Catches of Mullets nei are recorded mainly by South Africa. These tended to be above 1 000t until 1997, but have fallen in recent years and plunged to only 122t in 2002.
Sharks, rays, chimaeras (ISSCAAP Group 38) do not provide substantial catches in Area 47 although they have escalated in recent years. Catches of the group peaked in 1978 at a total of some 17 700t, made up primarily of unidentified sharks, rays, skates etc; unidentified Raja rays; and Cape elephantfish (Callorhincus capensis ). After this, total catches declined erratically until 1996 when the total recorded was just over 3 000t. Thereafter they started to climb again, reaching 15 200t in 2001 and declining only slightly to 13 800t in 2002. At that time catches were still dominated by the same species groups. Catches of blue shark (Prionace glauca ), shortfin mako (Isurus oxyrinchus) and smooth hammerhead (Sphyrna zygaena) are also consistently recorded.
In recent years there has been substantial interest in exploitation of the deep-sea species of the Southeast Atlantic, including orange roughy (Hoplostethus atlanticus) and alfonsino (Beryx splendens) as well as Patagonian toothfish (Dissostichus eleginoides ). Catches of the latter have been taken in the exclusive economic zone (EEZ) of South Africa at the Prince Edwards Islands (Commission for the Conservation of Antarctic Marine Living Resources [CCAMLR] sub-areas 58.6 and 58.7) and therefore fall outside the geographic area of this review. Almost all of the deepwater fishing in the Southeast Atlantic has been undertaken in Namibian waters. Catches of alfonsino peaked at over 4 000t in 1997 but declined thereafter and just over 200t were landed in 2002. Catches of orange roughy reached a peak of over 18 000t in 1997, declined steadily after that to 857t in 2001, and increased again to 2 169t in 2002. Exploitation of the deep-sea species by coastal states of Area 47 has been undertaken almost exclusively by Namibia.
Several crustacean species support valuable fisheries in the region (Figure B7.7). Geryon crabs, dominated by the red crab (Chaceon maritae ), are taken in both Namibian and Angolan waters. Recorded catches of Geryon crabs peaked at over 10 000t in 1993 but fell in the following years. A secondary peak of nearly 6 000t occurred in 2000, falling to approximately 4 100t in 2001 and 2002. The highest catches of crustaceans were of shrimps, particularly the deepwater rose shrimp (Parapenaeus longirostris) and the striped red shrimp (Aristeus varidens) which are taken mainly in Angolan waters. Catches of deepwater rose shrimp were over 5 600t in 2001, the highest figure since the start of the 1990s, but declined to 2 000t in 2002. The same pattern was observed with catches of the striped red shrimp, which reached 3 400t in 2001, the highest recorded since 1987, and declined to just over 2 000t in 2002.
The Cape rock lobster (Jasus lalandii ) and southern spiny lobster (Palinurus gilchristi )occur towards the south of the region, with the former occurring on the west coast of Namibia and South Africa and the latter off the south coast of South Africa. Catches of the Cape rock lobster have levelled off under TAC management at approximately 2 000t per year after a steady decline since the peak of over 25 000t per year in the 1950s. Catches in 2002 were just over 3 000t. Catches of southern spiny lobster, also managed by TAC, were reasonably constant between about 800 and 1 100t whole mass during the 1990s, but declined in 1999 and 2000, increasing to just over 1 000t in 2001 and declined again to 651t in 2002. The island of St Helena also occurs in Area 47, and it has recorded catches of Tristan da Cunha rock lobster (Jasus tristani )generally varying between 300 and 500t. The highest catches, over 800t, were reported for 1972 and 1976. The Natal rock lobster Palinurus delagoae occurs on the east coast of southern Africa and supports a directed trap fishery in Mozambique as well as occurring in catches of a mixed crustacean trawl fishery off the east coast of South Africa. However, an exploratory fishery in South Africa targeting the species has recently been closed after results obtained since fishing commenced in 1994 indicated very limited potential in South African waters (see Pollock et al., 2000, and other papers on these resources by the same authors).
Figure B7.7 - Annual nominal catches ('000t) of selected crustaceans, Southeast Atlantic (Area 47)
Source FAO
Figure B7.8 - Annual nominal catches ('000t) of selected species of molluscs, Southeast Atlantic (Area 47)
Source FAO
The major fisheries for molluscs in the region are for the Cape of Good Hope squid (Loligo vulgaris reynaudii )and for Perlemoen abalone (Haliotis midae ). The highest catches for squid, 10 730t, were made in 1989 and since then catches have shown considerable variability, as would be expected from a short-lived species, varying from a peak of over 7 500t in 1996 to a low of 2 800t in 1992 (Figure B7.8). Catches in 2002 were 7 400t. Catches of abalone have declined fairly steadily since a peak of over 4 000t in the mid-1960s but were maintained between approximately 550 and 750t from the mid-1980s to the late 1990s, before dropping further.
RESOURCE STATUS AND FISHERY MANAGEMENT
Most of the commercially important stocks within the region are classified as being between fully exploited and overexploited. The latter status is frequently, but not always, a result of historical over-exploitation rather than current excesses. In more recent years, again varying from stock to stock, more conservative management measures have generally been put in place and at present the most important resources are managed either for sustainable yields or with a goal of encouraging recovery. Both Namibia and South Africa have well-developed management systems in place for the fisheries exploiting their most important stocks, and Angola is also making progress in monitoring and implementing effective management for some of the important resources.
Nevertheless, in common with most fisheries in the world, substantial problems still exist in many fisheries, with varying underlying causes including environmental variability, scientific uncertainty and conflicting biological and socio-economic objectives. Difficulties in monitoring, control and surveillance occur throughout the region and are particularly significant in some coastal fisheries where access and catches are difficult to control. In South Africa, severe problems with illegal fishing are being experienced in the abalone (perlemoen) fishery. It has been difficult to estimate the size of the illegal take but an indication of the magnitude of the problem is that in 2002, more abalone, in terms of numbers, were confiscated by the law enforcement agency than were landed by the legal fishery. In addition, 55 percent of the illegally caught abalone that were confiscated were below the minimum legal size (Tarr and MacKenzie, 2002). In recent years, South Africa has also been experiencing problems in implementation of the new South African fisheries policy, developed after the 1994 democratic elections. Attempts to develop an appropriate system of access rights had met with substantial legal challenges, in some cases resulting in the suspension of fishing activities, until a solution had been reached. A new system of allocation of medium-term rights was launched in July 2001 and the indications of success at this stage are promising (DEAT, 2002).
The commercially important small pelagic stocks in all three countries are closely monitored, both by recording commercial catches and by making use of regular hydro-acoustic surveys. In South Africa, the stocks of pilchard and anchovy are managed on the basis of formal management procedures, which are negotiated decision rules developed using rigorous simulation models of the fishery (Cochrane, Butterworth and Payne, 1997; De Oliveira et al., 1998). The status of the small pelagic resources of the region varies from stock to stock, with current conditions apparently being generally more favourable in the south and less so in the north. The South African stock of sardine remains in a very healthy state, and the biomass estimated on the hydroacoustic survey in November 2002 was the highest since surveys started in 1985 and, at 2.5 million tonnes, nearly onemillion tonnes up on that of the previous year. In contrast that of Namibia remains worryingly low. The anoxic event in 1993 and 1994 and the Benguela Niño in 1995, both led to poor recruitment which, in combination with continued fishing, are thought to have been the primary causes of the decline in Namibia. After those adverse environmental conditions, the environment was more favourable in the spawning season of 1995–1996 (Namibia Foundation, 1998). However, there was no sustained improvement in status and in 2002, a zero TAC was set by the Ministry of Fisheries and Marine Resources in response to serious concern about the status of the resource. Early indications are that this measure has had a positive impact, and surveys in October 2002 and March/April 2003 resulted in estimates of biomass of over 300 000t and 550 000t respectively, substantially higher than the 40 000t estimated in March 2002.
The South African stock of anchovy is in a healthy condition. The biomass estimated on the November 2002 survey was 2.5 million tonnes. This is considerably lower than the record 4.4 million tonnes estimated the previous year, but still the third highest biomass estimate since surveys started in 1985. Fishing for Whitehead's round herring, which occurs mainly in South Africa, is not directly regulated at present, as assessments have suggested that it is being underexploited. However, with the recent increases in catches of the species, this approach is currently being re-examined.
The biomass estimates for Angolan waters of the two species of sardinella combined showed substantial variability during the 1990s, ranging from 164 000t in February/March 1995 to 574 000t in August of the same year (Bianchi, 1999). However, the very low biomass estimate of February/March 1995 was attributed to the unusual schooling behaviour displayed by sardinellas in connection with the extreme environmental conditions observed in that period (very high water temperatures and low salinity in the upper 50-m water layer that were later ascribed to the “95 Benguela Niño”). Trends in biomass estimates from the surveys carried out in the winter season (August–September) are more consistent and show an increase in biomass in the mid-90s as compared to the mid-80s. Although biomass seems to have decreased again in later years, it is still higher than at the time of heavy exploitation by the USSR. The flat sardinella is still dominating the catches and accounts for about 75 percent of the total sardinella biomass. An assessment of sardinellas in Angola, Congo and Gabon, undertaken in 1997, suggested that the combined sardinella resource was underexploited at that time (FAO, 2000). However, there is a need for caution if the fishery is to be developed, particularly in view of the uncertainty about the magnitude of catches taken by the artisanal fisheries.
The stock structure of the Cape horse mackerel population of the Southeast Atlantic is not clear, although for management purposes they are treated in the same way as sardine, as separate stocks in Namibia and South Africa, separated by the upwelling cell off Lüderitz. The South African stock is managed by a catch limit on adults on the Agulhas Bank and a bycatch limit on juveniles taken in the pelagic fishery on the West Coast. The adult catch limit has rarely been fully subscribed in recent years, and the species is generally considered to be underutilized. However, in 1997, a joint venture involving a large Russian midwater trawler was entered into to increase exploitation of the South African stock (Verheye, 1998). In 2001, fishing rights for horse mackerel in South Africa were allocated to 18 companies as a part of a plan to develop the fishery in an incremental fashion (DEAT, 2002). In Namibia, the stock is an important contributor to the national fishery and is fished by midwater trawl and a purse-seine fleet. The stock is considered to be resilient and its status variable, but there was evidence of a decline in abundance between 1999 and early 2003 (MFMR, 2002 and G. D'Alemida, NatMIRC pers comm.). In 2000, the total stock biomass was estimated to be in the order of 1 million tonnes (Krakstad, 2002). The stock, shared with Angola, is considered to be fully exploited (Namibia Foundation, 1998). The Cunene Horse mackerel is another important pelagic species north of the Angola-Benguela front. Biomass estimates from the winter surveys show a similar trend to that of the sardinellas, with an increase in the mid-1990s from the lower levels in the 1980s. Recent trends indicate a drastic decrease in biomass, particularly affecting the adult part of the population (IIM, 2001). An assessment undertaken in 1997 estimatedthe resource to be underexploited, contributing to the growth in biomass in the mid-1990s. However, more recent estimates by the Instituto de Investigaçao Marinha (IIM) indicate a condition of growth overfishing and measures are being taken to limit the fishery (IIM, 2001).
The Cape hakes are found in Namibia and South Africa and the Benguela hake (M. polli) occurs north of the Cunene River, the border between Namibia and Angola. Each State manages the fisheries occurring in their own EEZs. The shallow water Cape hake (M. capensis ) used to dominate the catches from Namibia, and is still dominant in catches from the south coast of South Africa. The deepwater Cape hake (M. paradoxus ) is an increasing component of catches from Namibia and dominates catches from South Africa's west coast, but the two species are not identified separately in commercial catches. Until recently, because of difficulties in separating the two Cape hake species in commercial catches, South Africa assessed the two as a single stock (Payne and Punt, 1995), but separate assessments are now being attempted. At the time of writing in mid-2003, M. capensis on the south coast was assessed separately whereas a combined species assessment was conducted on the West Coast. An ad hoc adjustment to the west coast estimate is made to account for M. paradoxus on the south coast. Work has begun to develop separate assessments for west coast M. capensis, south coast M. capensis and a combined assessment of M. paradoxus for both coasts (R. Rademeyer, University of Cape Town and R. Leslie, MCM, pers comm. ). Recent assessments estimated the biomass of M. capensis on the south coast in 2002 to be close to that producing maximum sustainable yield level (MSYL). That of M.paradoxus wasestimated to be substantially below MSYL on both the west coast and for both coasts combined. The biomass of both species combined on the west coast was higher in relation to the MSYL than that of M. paradoxus alone. Overall, therefore, the status of M.capensis in South Africa is thought to be considerably better than that of M. paradoxus .
Namibia has implemented an observer programme which enables commercial catches of hakes to be split by species and, based on results from this programme, it was estimated that the deepwater Cape hake accounted for about 80 percent by mass of the Namibian hake catches in 1997 (Voges et al., 1998). Nevertheless, the assessments in Namibia are currently undertaken on both species combined and make use of commercial catch-per-unit effort (cpue) information and the results of research surveys. Problems are being faced in achieving reliable assessments of the resource because of the highly variable nature of these data. This means that estimates of quanities such as MSY and stock status, which are obtained using age-structured production models, are not precise and have varied substantially in recent years as more data have become available. Survey results over the past decade have shown little overall trend although, following a peak in 1998, there was a decline in survey estimates of biomass until 2001, stabilizing in 2002. However, cpue now shows a clear decline. This has resulted in assessments of decreasing optimism over recent years, and allowable catches for 2003 were consequently reduced in accordance with the management procedure used to provide recommendations for the resource.
Fisheries targeting tuna and tuna-like species (ISSCAAP Group 36) are also important in Area 47, attracting several distant water fishing nations in addition to participation by the coastal states. Big eye tuna Thunnus obesus supported the highest catches in 2001, followed by albacore Thunnus alalunga, swordfish Xiphias gladius, southern bluefin tuna Thunnus maccoyii and then a number of other species. South Africa and Namibia landed more albacore than any other species in this ISSCAAP group in 2002, while the highest catches by Angola were of Atlantic bonito Sarda sarda in 2001 and of Tuna-like fishes nei (Scombroidei) in 2002.
ICCAT is responsible for the assessment of these species and stocks and for the management of fisheries exploiting them. It regularly assesses the status of some of the more important of them. Big eye tuna is considered to consist of a single, Atlantic wide stock. According to ICCAT's assessments (ICCAT, 2002), the biomass of big eye tuna is below the MSYL, and fishing mortality is above the rate that would achieve maximum sustainable yield (MSY). The assessment was, however, hampered by a lack of data from several of the more important fisheries on the stock. The albacore caught in Area 47 would be a part of the southern Atlantic stock and the biomass of this stock, as estimated in 2000, is thought to be above the MSYL, but the assessment was not considered by ICCAT to be very reliable. Concern was expressed by ICCAT at the escalation in catch of albacore reported in 2001. Swordfish in the region are considered to be part of a South Atlantic group. In 2002, ICCAT reported that they had been unable to complete a reliable assessment for swordfish due to conflicting trends in the available catch per unit effort series. It was noted that the total catches of the group had declined since 1995, as had been recommended by ICCAT, although some countries had increased their catches. The Commission for the Conservation of Southern Bluefin Tuna assessments of southern bluefin tuna (as reported by ICCAT, 2002) indicated that the biomass had been largely stable since the early to mid-1990s, but remained below the target biomass: the biomass estimated for 1980. Recruitment has been low in recent years relative to that of earlier years in the history of the fishery.
The species composition of demersal assemblages off Angola display important changes in a north-south direction, the fauna being predominantly subtropical-temperate off southern Angola and tropical and more diverse in the central and northern parts. Seabreams (Sparidae) and croakers (Sciaenidae) are prominent components of the fauna both in abundance and economic interest. In the southern shelf (south of Tombua), large-eyed dentex and African weakfish are the main species, also fished commercially. Biomass estimates for both species dropped substantially in recent years (Johnsen et al., 2003). A decrease in seabream biomass (including several species of Dentex and Sparus) was also observed in the central region while the estimates seem to be more stable in the northern area (north of Pta. das Palmeirinhas; Johnsen et al., 2003).
In addition to the major fish species described above, many other species contribute to the fisheries of the region. For example, more than 200 species make up the catches from South Africa's line-fishery (Verheye, 1998) of which 20 can be considered to be economically important (Griffiths, 2000). The global catches of fish reported to FAO are included in 150 different taxonomic groups, many of which are at the level of Genus or higher and include a number of individual species. Within the region, there is much less information on the status of most species and stocks than there is on the few commercially more important stocks discussed above. However, South African catches of species such as seventy-four seabream (Polysteganus undulosus ), red steenbras (Petrus rupestris ), African weakfish, known locally as geelbek, (Atractoscion aequidens) and others have fallen considerably since the 1960s when line-fish catches peaked (Verheye, 1998). In Namibia, there is evidence that the abundance of kob has declined in recent years (Namibia Foundation, 1998). A recent analysis of trends in cpue of linefish species in South Africa indicated that many were severely overexploited during the 20thcentury. In order to address this and to allow the depleted stocks to recover, South Africa is aiming to achieve a 70 percent reduction in commercial effort in the linefishery, accompanied by stringent regulations to recreational fishing (M. Griffiths, MCM, pers. comm. ).
Both Namibia and South Africa have developed national plans of action in accordance with the FAO International Plan of Action for the Conservation and Management of Sharks.
Namibia has taken a cautious approach to the development of a fishery for its deep-sea resources, which started with a small experimental fishery in 1994. Recent assessments for orange roughy suggested that the high catches of the early period in the development of the fishery would not be sustainable and a precautionary management scheme has been implemented. This scheme has established four quota management areas, with a separate TAC for each area. Few data are available for alfonsino, but it is expected that, as with orange roughy, the yield will be considerably less than the initial TAC.
In response to the interest in and potential of deep-sea resources of the Southeast Atlantic Ocean, and out of concern to ensure that the region's resources are utilized in a rational and responsible manner, the coastal states of the region: Angola, Namibia, South Africa, and the United Kingdom, on behalf of St Helena and its dependencies Ascension and Tristan de Cunha, took the initiative in 1997 to begin negotiations for the establishment of a regional fisheries management organization, the South East Atlantic Fisheries Organization (SEAFO), within the framework of the 1995 UN Agreement on Straddling Fish Stocks and Highly Migratory Fish Stocks. The European Union, Iceland, Japan, the Republic of Korea, Norway, Poland, the Russian Federation, Ukraine and the United States of America also participated in the negotiations as Interested States.
The area managed by SEAFO includes a substantial portion of the high seas of the south east Atlantic and covers alfonsino, orange roughy, armourhead grenadier, wreck fish, deepwater hake and red crab. The agreement was signed on 20 April 2001 by the coastal states of Angola, South Africa, Namibia and the United Kingdom of Great Britain (on behalf of St.Helena and its dependencies of Tristan da Cuhna and Ascension Island) and the deepwater fishing nations: the European Community, Iceland, Norway, Republic of Korea and the United States of America. The SEAFO Convention has recently come into force after ratification by three signatory States: Namibia, the European Union and Norway.
Tagging results suggest that there is a single stock of deep-sea red crab (Chaceon maritae) shared between Namibia and Angola. Assessment of the stock indicated that it is currently fully exploited and that, from 1990, the biomass had been stable at approximately 40 percent of the biomass in 1980, at which time it had been moderately fished for seven years (Namibia Foundation, 1998). More recent results suggest that the stock is increasing in biomass (MFMR, 2002). Preliminary assessments of the Angolan stocks of deepwater rose shrimp (Parapenaeus politus) and striped red shrimp (Aristeus varidens) were undertaken early in 1999 (FAO, 1999). The results suggested that catches of the deepwater rose shrimp in 1997 were above the estimated MSY and that the stock is fully to overexploited, with a biomass considerably lower than that in 1985/1986. The estimated MSY for striped red shrimp was similar to the mean catch for the period 1993 to 1997, although the reported catch for 1997 was lower than the MSY. The biomass of the striped red shrimp is similar to that in 1985/86 and the stock is considered fully exploited.
The Cape rock lobster (Jasus lalandii) has been the subject of intense monitoring and assessment for nearly a decade, following a sudden decline in somatic growth rates and hence in productivity in the late 1980s. Current estimates are that the stock has undergone a major decline since catches peaked in the 1950s, and that the resource is estimated to be depleted. As a result, a formal management procedure has recently been adopted for the stock in South Africa which, while aiming to sustain some fishing, is projected to lead to a 15 percent increase in the fishable component of the population between 1996 and 2006 (Cockroft and Payne, 1999; D. Butterworth, UCT, pers comm.). Recent stock assessments indicate some growth in the biomass since the end of the 1990s. In Namibia, the stock of Cape rock lobster is similarly estimated to be depleted, but has shown signs of modest recovery under low TACs implemented since 1992 (Namibia Foundation, 1998 and MFMR, 2002).
The other important crustacean stock in the region is the southern spiny lobster (Palinurus gilchristi) which is estimated to have declined continuously between the 1988/1989 season and 1998/99. Between 1998/99 and 2002/2003 it is estimated to have grown considerably, allowing for an increase in the TAC for 2003/2004 (MCM, 2004).
The Cape of Good Hope squid (Loligo vulgaris reynaudi ) is managed on the basis of effort control and a closed season. Being a short-lived species, catches in any year are heavily dependent on recruitment to the fishing grounds that year. Recent assessments have indicated that the stock is fully exploited and that effort must be reduced in the future if sustainability is to be achieved; adjustements to the duration of the closed season are used to try to limit effort, (MCM, 2000, 2004).
The prognosis for the stock of abalone (Haliotis midae) in South Africa is pessimistic given the current scale of illegal harvests. Fishery independent diver surveys have been undertaken annually since 1995, and the resulting time-series have only recently become long enough for inclusion in comprehensive assessments of the resource. The commercial fishery is managed by TACs which were kept relatively constant in recent decades but have been steadily reduced since 1996–1997 in response to a number of warning signals (Verheye, 1998). In particular, there is concern that poaching is currently seriously impacting the resource. In recent years, a new, ecological problem has also emerged. In the early 1990s, West coast rock lobster moved into a significant part of the range of abalone. The lobsters reduced the local population of sea urchins Parechinus angulosus, which they feed upon. Sea urchins provide important shelter for juvenile abalone and their disappearance from the area has allegedly exposed the young abalone to predation by the lobsters and other predators, negatively impacting the reproductive success of the stock (Mayfield and Branch, 2000; Tarr and McKenzie, 2002).
REFERENCES
Bianchi, G. 1999. Overview of the pelagic surveys by the RV Dr Fridtjof Nansen off Angola, Congo and Gabon (1985–1997). In Cochrane, K.L. and M. Tandstad (eds.) Small Pelagic Resources of Angola, Congo and Gabon. Workshop Report, Luanda, Angola, 3–6 November, 1997. FAO Fish. Rep. 618 pp. 52–68.
Cochrane, K.L., Butterworth, D.S. & Payne, A.I.L. 1997. South Africa's offshore living marine resources: the scientific basis for management of the fisheries. Proceedings of the Royal Society of Southern Africa, 52: 149–176.
Cockcroft, A.C. & Payne, A.I.L. 1999. A cautious fisheries management policy in South Africa: the fisheries for rock lobster. Marine Policy 23(6), 587–600.
DEAT. 2002. Where have all the fish gone? Measuring transformation in the South African fishing industry. Department of Environmental Affairs and Tourism, Pretoria, South Africa. 28 pp.
De Oliveira, J.A.A., Butterworth, D.S., Roel, B.A., Cochrane, K.L. & Brown, J.P. 1998. The application of a management procedure to regulate the directed and bycatch fishery of South African sardine Sardinops sagax. S. Afr. J. mar. Sci. 19: 449–469.
FAO. 1999. Report of the Workshop on the Assessment and Management of Shrimps and Crabs in Southwest Africa. Luanda, Angola, 8–12March 1999. Project GCP/RAF/302/EEC Improvement of the legal framework for fisheries cooperation, management and development of coastal states of West Africa, 107p, Document 62.
FAO. 2000. Small Pelagic Resources of Angola, Congo and Gabon. eds. Cochrane, K.L. and M.Tandstad. Workshop Report, Luanda, Angola, 3–6 November, 1997. FAO Fish.Rep . 618. 149 pp.
Griffiths, M.H. 2000. Long-term trends in catch and effort of commercial linefish off South Africa's Cape Province: snapshots of the 20th century. S. Afr. J. mar. Sci. 22: 81–110
ICCAT. 2002. Report of the Standing Committee on Research and Statistics (SCRS), September 30 to October 4, 2002, Madrid, Spain.
Instituto de Investigaçao Marinha (IIM). 2001. Pequenos peixes pelagicos. (internal report)
Johnsen, E.E., Zaera, D., Olsen, M., Johansson, T.E. & Kilongo, K. 2003. Surveys of the fish resources of Angola. Survey of the demersal resources, 28 February – 1 April 2003. Cruise Reports R.V. Dr. Fridtjof Nansen, Bergen, Norway. 69 p. and 10 annexes.
Krakstad. 2002. The Namibian horse mackerel stock - summary of the resource and management. In Report of the Workshop on Trophic Interactions in the Benguela ecosystem and their implications for multispecies management of fisheries. GCP/INT/643/Japan, Rep 2.5. 42 pp.
Mayfield, S. & Branch, G.M. 2000. Interrelations among rock lobsters, sea urchins, and juvenile abalone: implications for community management. Can. J. Fish. Aquat. Sci. 57(11): 2175–2185.
MCM. 2000. Research highlights 1999–2000. Marine and Coastal Management, Cape Town. 74 pp.
MCM. 2004. Research highlights 2002–2003. Marine and coastal management, Capetown 69 pp.
MFMR. 2002. Information on Namibia's Fisheries Management System for the FAO Digital Atlas. MFMR, Namibia. 27 pp.
Namibia Foundation. 1998. Namibia Brief: Focus on Fisheries and Research. No. 20, 2nd Edition. Namibia Foundation, Windhoek. 172 pp.
Payne, A. I. L. & Punt, A. E. 1995. Biology and fisheries of South African Cape hakes (M.capensis and M. paradoxus ). In Alheit, J. & Pitcher, T. J. (Eds.). Hake: Biology, Fisheries and Markets . London; Chapman & Hall: 15–47.
Pollock, D.E., Cockcroft, A.C., Groeneveld, J.C. & Schoeman, D.S. 2000. The commercial fisheries for Jasus and Palinurus species in the South-east Atlantic and South-west Indian oceans. In Spiny Lobsters: Fisheries and Culture - 2nd Edition (Ed. by B.F. Phillips & J. Kittaka), pp 105–120. Blackwell Science Publications, Oxford, UK.
Tarr, R.J.Q. & Mackenzie, A.J. 2002. Overview of the South African abalone fishery: biology, management, research, poaching. Unpublished Rep. BEN/DEC02/SAA/1a. Cape Town, MCM. 9 pp.
Verheye, H. (Ed.) 1998. Research Highlights. 1997–1998 . Sea Fisheries Research Institute, Cape Town. 68 pp.
Voges, E., Burmeister, L., Kirchner, C., Leth, N., van Wyk, J.D., Vaske, B & Lassen, H. 1998. An assessment of the Cape hake (Merluccius capensis) off Namibia based on bottom trawl survey data obtained by the NORAD R/V Fridtjof Nansen from 1990–1998 and length compositions for the 1997 Namibian commercial fishery. Unpublished report of Project FAO/DANIDA/575/GEN. FAO, Rome. 37 pp.
* FAO, Marine Resources Service, Fishery Resources Division
by Ross Shotton *
INTRODUCTION
The Western Indian Ocean area (Figure B8.1) has a surface area of about 30 million km2, of which approximately 6.3 percent is shelf area, and encompasses regions with greatly differing oceanographic and fishery resource characteristics. The Northwest Arabian Sea is influenced by both Northeast and Southwest monsoons and includes extremely productive areas because of nearly continuous upwelling off the Oman coast (Sharp, 1995). Areas with seasonal upwelling occur off the coast of Iran, Pakistan in the Gulf of Oman and the Indian coast along the Arabian Sea, which also results in periods of high productivity. The Persian Gulf, a shallow enclosed area, is characterized by high-temperature highly saline waters and has fisheries that target species associated with reefs and shallow tropical seas. Water enters from the Gulf of Oman forming a counter-clockwise gyre and exits as a submerged denser, warmer and more saline water mass moving towards the centre of the Indian Ocean. The Persian Gulf is shallow, no part is deeper than 200m and much of the area to the north and west is less than 50m deep. It is fringed with extensive coral areas on the Arabian side. Around the Gulf of Oman the continental shelf is extremely narrow and fisheries concentrate on pelagic species, which in the last decades has increasingly meant the medium-sized pelagics such as Spanish mackerels (Scomberomorus spp.) and various species of tunas.
Figure B8.1 - The Western Indian Ocean
Past conflicts in the area (the Iran-Iraq war in the 1980s, the invasion of Kuwait and the subsequent operation Desert Storm) severely affected the fisheries, both through disruption of fishing activity and through environmental effects arising from oil pollution, or at the time of the invasion of Kuwait and operation Desert Storm, from the shadowing and pollution caused by burning crude oil wells. For example, in 1991 there was a complete failure of spawning by grouper caused by effects from the burning of oil and in the immediately following years, shrimp landings declined significantly (Mathews, Toloday and Ismail, 1993). In general, there has been a good recovery from these catastrophes though research continues into the impacts on coral reefs of the 1991 war. The increased diversion of waters flowing into the Shatt al Arab, the confluence of the Tigris and Euphrates rivers, is a continuing concern of the Persian Gulf countries. This reduction in freshwater inflow, and thus nutrients, has arisen from human-made changes, mainly drainage of the marsh areas near the opening of the Shatt al Arab with the Gulf but also through diversion of waters in countries further upstream such as Turkey. Ecological theory predicts that this must affect the biological productivity of the Gulf but no information exists to quantitatively estimate the consequences. With “regime change” in Iraq, water flow to the pre-existing marsh area is already being resumed and researchers in the area are planning to monitor future changes in the northern Persian Gulf.
Figure B8.2 - Annual nominal catches ('000t) by ISSCAAP species groups in the Western Indian Ocean (Area 51)
Source FAO
In the Red Sea, narrow continental shelves and its enclosed nature also create unique fisheries situations. Extensive demersal resources are primarily found in association with the wider continental shelves off the Eritrean coast (around the Dahlak Archipelago) and nearly opposite, along the southern Red Sea coast of the Yemen. The Gulf of Aden and Somali coasts are also monsoon-influenced upwelling areas that experience seasons of high productivity. Area 51 contains several small oceanic islands, Seychelles, Mauritius and Comoros, that have their own characteristic fisheries reflecting their oceanic or near-oceanic character. Further to the south, South Africa has fisheries of temperate and sub-Antarctic nature. Many of the countries of the region have important penaeid shrimp fisheries, notably, Madagascar, Mozambique, the countries of the Persian Gulf, and to a lesser extent, Tanzanian, Yemen and Kenya and, in the Red Sea, Yemen.
The possible development of a meal fishery for lantern fishes (myctophids - Benthosema pterotum) in the Gulf of Oman and Arabian Sea continues to tantalize, but a profitable development of a fishery for this resource remains unaccomplished. Trial fishing off the coast of Oman was abandoned because of continued damage to the small mesh nets caused by the teeth of ribbon fish (Trichiuridae )which were taken as a bycatch and the pioneering company stopped operating. Much work remains to be done on the stock structure of lantern fishes, the seasonal and annual variation in their abundance and what oceanographic factors drive this, and on the potential impact of a lantern fishes fishery on the other components of the ecosystem in the area, especially the large migratory scombrids. In the Red Sea, ecotourism is becoming an increasingly important activity, not only in the two northern gulfs but also in Eritrea, and only now is the beauty (and economic potential) of the coral reefs in the area becoming fully appreciated. The fisheries situation in Somalia remains dismal, with no collection of catch statistics and reports about unregulated and illegal fishing remain common.
PROFILE OF CATCHES
Interpretation of landing statistics for the Western Indian Ocean is complicated by the fact that many countries of the region continue to have difficulties in collecting accurate catch data. In some cases, countries have attempted to estimate catches by extrapolating from earlier years, but when this process is continued for an extended period significant biases may occur and it is uncertain if actual catches are over, or underreported. Recent work in one of the Sub-Area's countries indicates that reported landings for well beyond the last decade may have been overestimated by a factor of six.
Reported nominal catches averaged slightly over onemillion tonnes per year during the 1960s, increased to approximately 2.6 million tonnes per year during the 1980s and reached a peak of 4.2 million tonnes in 2002 (Figure B8.2 and Table D8). Of the 153 categories of species type catches reported in 2002, 21 landings categories presented 80 percent of the catch. Ignoring the aggregate group “Marine fishes nei” (not elsewhere included) at 16.5 percent), skipjack tuna (Katsuwonus pelamys) were the most abundant single reported category (9.3 percent of total reported catches) followed by Indian oil sardine (Sardinella longiceps) 9.2 percent; Sciaenids 6.2 percent; yellowfin tuna (Thunnus albacares) 5.7 percent; hairtails and scabbardfishes nei (Trichiuridae) 3.0 percent; shrimps (Natantia) 3.0 percent; Bombay duck (Harpadon nehereus) 2.4 percent; and pelagic percomorphs (Perciformes) 2.3 percent (Figures B8.3, B8.4, B8.5 and B8.6). Not surprisingly in such as large Statistical Subarea, there are considerable regional variations. In the Red Sea, pelagic “percomorphs” represent 35.1 percent of the reported catches; demersal percomorphs 6.9 percent, Spanish mackerel (Scomberomorus commerson ) 8.8 percent and Marine fishes nei 5.6 percent.
In the Regional Committee on Fisheries Commission Area - RECOFI - (Persian Gulf and the Gulf of Oman), the major species reporting categories were Marine fishes “nei” 23.7 percent; Indian oil sardine 10.1 percent; Longtail tuna (Thunnus tonggol ) 7.3 percent; Emperors (=Scavengers) (Lethrinids) 6.3 percent; Groupers (Serranidae) 5.0 percent and yellowfin tuna 4.8 percent. Outside of these regions, i.e. in the Indian Ocean proper, the most important constituents of the catch were marine fish “nei” (15.2 percent), Indian oil sardine (9.8 percent); skipjack tuna (8.3 percent); Sciaenids (7.3 percent); yellowfin tuna (5.5 percent); Bombay duck (4.4 percent); green tiger prawn (4.2 percent) and cephalopods, (3.2 percent).
Eastern Arabian Sea: Pakistan, India and the Maldives
Reported catches for this area reached a peak in 1997 of 2.55 million tonnes and have been roughly stable at this level since (2002 landings were reported to be 2.56 million tonnes). The changes in reported catches by country for the Western Indian Ocean have not been consistent over the last decade. Both India and the Maldives report increases of 12 and 78 percent, respectively, for this period while Pakistan has shown a small decrease of 3.0 percent Over the period 2000–02 catches have changed, with a 4 percent decrease in Pakistan and 8 and 22 percent increases for India and the Maldives.
Figure B8.3 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 35 & 37, Western Indian Ocean (Area 51)
Source FAO
Over the period 2000–02, greatest increases in catches (for categories recording more than 1 000t of catches) were for Marine crustaceans (Crustacea) from 11 047t to 30 769t in 2002. Among species with significant landings, the Indo-Pacific king mackerel (Scomberomorus guttatus) recorded the largest relative increase in landings, 175 percent, followed by Ponyfishes (Leiognathidae) at 136 percent, Unicorn cod (Bregmaceros mcclellandi) at 87 percent and Goatfishes (Upeneus sp.) at 82 percent. Among small pelagics, Kelee shad (Hilsa kelee) showed a major increase, up 42 percent to nearly 6 000t. Among species showing essentially no change were groupers (–0.07 percent), cuttlefish and bobtail squids nei (-0.09 percent) and mangrove red snapper (-0.09 percent). In the category of species declines, greatest reduction was shown by Kawakawa (Euthynnus affinis) (–79 percent), marlins and sailfishes (Istiophoridae) (–71 percent), Frigate and bullet tunas (Auxis thazard, A. rochei) (-52.6 percent) and Lizardfishes nei (Synodontidae) ( -42 percent).
Figure B8.4 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 33, Western Indian Ocean (Area 51)
Source FAO
Figure B8.5 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 36, Western Indian Ocean (Area 51)
Source FAO
Figure B8.6 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 45, Western Indian Ocean (Area 51)
Source FAO
The Persian Gulf and Gulf of Oman
Analysis of catches from this area, FAO Sub-areas 51.2 and 51.3 are slightly complicated by the fact that some part of the Omani landings are taken from outside of this area. However, it is believed that this difference is not large, though it is planned to make explicit accommodation for this in the future. Total landings for this area continue their increase from that reported in 1998 (535 000t) to a high of 586 600t in 2001, an all time high. A worrying fraction of the landings are still reported in a completely aggregated form, i.e. Marine fishes nei, 23.7 percent (compared to 25.2 percent in 2000) indicating that much uncertainty must remain in the data recorded for this area. Indian oil sardine remains the single largest reported catch entity (10.1 percent of total landings), with 47 percent increase over the 2000 results. Longtail tuna, the next most abundant species contributed 7.3 percent, a decline of 12 percent from the preceding year. Narrow-barred Spanish mackerel (Scombermorous commerson) continues its downward trend that started in 1995 when 30 610t were landed, down to 18 454t in 2001, a decline that has been the subject of much concern in the region. Shrimp catches, at 15 664t, while above the decade's low of 10 880t taken in 1999, are down from the 2000 landings by 18.9 percent. The other species group of major concerns - groupers and Serranids - landings data indicate that global catches remain stable, the 2001 result of 6 681t is within the decade range of 4120–7 148t.
The Red Sea and Gulf of Aden
Reported catches from the Red Sea continued their steady increase of the last decade, reaching 299 190t in 2001, a 55.8 percent increase over this period. Some of this may be from improved reporting practices, but irrespective, this is a relatively substantial increase compared to other FAO statistical areas. This result also represented a 6.9 percent increase over the 2000 landings. In terms of species, Pelagic percomorphs nei remained the main reported category, indicative of the weak statistical reporting practices in FAO statistical Subarea 51.1. This was a 26.6 percent increase in absolute year-to-year landings of a group that represented more than a quarter of all reported landings - 27.0 percent. The next largest category was equally unhelpful, Marine fishes nei which represented 10.9 percent of the landings, only a minor change from the year before (–1.1 percent). Thus just under 40 percent of reported landings are in an aggregated form that prevents effective monitoring of trends in landings of particular species, much less stocks. For those where specific data have been provided, the dominant species in the catch is narrow-barred Spanish mackerel - 8.5 percent of total landings, a 3.2 percent increase of 2000 and a 1029 percent increase during the last decade. This increase, which matches the declines in landings for this species in Sub-Areas 51.2 and 51.3 may indicate a shared fishery. Other fishes registering increases over the 2000 results were the Mugilide (56.8 percent), Lethrinidae (22.6 percent), Serranidae (3.5 percent) and elasmobranchi (22.8 percent). Major declines in catches were recorded for crabs, to 1 783t (–43.6 percent); Scomberoides to 543t (–33.4 percent) - though this may have arisen from improved dissaggregation in the catch; undifferentiated Natantia (–31.1 percent), though this was matched by an increase in landings of Penaeids to 7 151t (7.0 percent); lutjanids to 9 115t (–26.8 percent) but still above 1997 catch levels; Sardinella spp. to 4 343t (–23.9 percent) and Synodontidae to 10 686t (–23.1 percent). Over the decade 1992–2001, greatest decreases in reported catches were for “Caranx spp.” –90.7 percent, lobster (Panulirus spp.) –64.0 percent, Indian mackerel (Rastrelliger kanagurta) –35.3 percent and threadfin breams (Nemipteridae) –22.9 percent.
Coastal East Africa (Somalia to Mozambique)
Catches by regional countries in the south-western part of the Western Indian Ocean have been somewhat stable during the last decade, with 2001 catches (319 000t) representing an all time high, though gains were recorded in only four of the last 10 years. Many of the reported catches are not identified to species (33.4 percent in 2001 - part of a recent increasing trend - though down considerably from the 42 percent recorded in 1994), and therefore a useful analysis by species is not possible. Total catches in this area increased by 2.2 percent from 2000 to 2001, and were 10.6 percent greater than those of a decade earlier. Distant water fishing countries continue to be the major harvesters, lead by Spain, Taiwan Province of China, Japan, France and Uruguay. Of major importance in the period 1997–2002 has been the development of deepwater fisheries targetting seamounts in the southern Indian Ocean. These fisheries have followed the pioneering exploration and fisheries of the Soviet Union (Romanov, 2003). A major difficulty has existed in obtaining the data for these operations. However, in 1999, vessels from seven countries harvested 14 526t consisting of orange roughy, oreos, alfonsino, boarfish, cardinal fish and bluenose. By 2000, these catches had increased to 39 413t, but by 2001 known landings were down to 7 965t. Greatest reductions had been in orange roughy. Many of the management concerns related with this exploitation are discussed in FAO (2001 and 2002).
On a species basis, of particular relevance (>500t reported per year) skipjack tuna were the most important component of the catch (18.3 percent) followed by yellowfin tuna (14.3 percent), Sardinella spp.(4.9 percent) and undifferentiated shrimp (4.5 percent). Greatest year-to-year increases in reported catches for specifided groups were Lutjanidae (356 percent), Albacore (Thunnus allalunga) (51.9 percent) and shrimp (Penaeus spp.) (51.9 percent). Major reductions were recorded for Scombroidei (–52.3 percent), though this could be due to changes in reporting practices, Rastrelliger spp. (see earlier comment) and black marlin (Makaira indica) (–50.0 percent).
RESOURCE STATUS AND FISHERY MANAGEMENT
Eastern Arabian Sea: Pakistan, India, Maldives and Sri Lanka
The enormous number of small fishing vessels in this area complicates monitoring of stock status and makes implementation of fisheries management measures difficult. In many cases no restrictions exist on entry into the fishery for social reasons. Rather, regulations control the type of gear that can be used. In many areas, almost any form and size of fish that can be caught is saleable. Given the scarcity of alternative employment, fishing intensity remains high, increasing whenever the catch rates and economic conditions allow it to do so. Socio-economically, small-scale shrimp fisheries are important in both Pakistan and along the west coast of India. Gear restrictions are few and there is little active regulation of fisheries. Most commercial species are heavily exploited. Consequentially, concerns must exist regarding overfishing and ecosystem modification caused by trap and gillnet fishing in coral reef areas; the effects of intensive demersal trawling, usually aimed at shrimp remains unknown. It is believed that major resource and economic benefits would arise from a reduction in fishing effort in fisheries for shrimp in these regions but explicit analyses of the bio-economics of these fisheries remain to be done.
The Persian Gulf and Gulf of Oman
Fisheries have been important in this area since ancient times, both for subsistence purposes and trade. The pearl fishery of the Persian Gulf, once famous, now continues at a fraction of what it was in former times. Rising incomes and the traditional popularity of fish as a dietary item have resulted in full exploitation of virtually all fisheries resources of the area, with the exception of the Indian round herring, mainly because of lack of consumer demand resulting from its oily nature. The fisheries of today are prosecuted by motorized dhows and sambuks, smaller wooden vessels and industrial-style trawlers nearly all of which use ice for preservation of the catch. These are found in most countries of the region, except in the United Arab Emirates, where trawling has been banned, and Iran, which has severely limited the use of trawlers inside the Gulf where such fishing is only permitted during the shrimp fishing season. The Iranian industrial fishery that used to operate within the Persian Gulf is now restricted to fishing in the Gulf of Oman and Northwest Arabian Sea.
Three resources remain of major concern in this area: Spanish mackerel, shrimp (various Penaeid and Metapenaeid species) and various percid fishes but in particular those of the grouper family. Accurate information on the state of individual stock and species continues to remain difficult to obtain, if it exists at all, because of the common practice of reporting catches data in a highly aggregated form. The available catches data suggests that most fish groups are fully exploited while major concerns exist regarding the status of narrowed-barred Spanish mackerel, a premium fish in great market demand.
The Red Sea and Gulf of Aden
The Red Sea and to a lesser extent, the Gulf of Aden, being ancient sea ways have also been, at least regionally, important for their fisheries. However, the oligotrophic nature of the Red Sea, a body of water surrounded by countries with narrow continental shelves and coral outcroppings, means that fisheries, while significant locally, are not important in global terms. Several coastal states have had regionally important shrimp fisheries, particularly Saudi Arabia and the Yemen and, to a lesser extent, Eritrea. As in many tropical areas, the fisheries resources are those characteristically associated with coral reefs, small pelagics fisheries and those for the larger more mobile scrombroids, including some tunas. Where possible, trawl fisheries are carried on, generally using trawls with small mesh in their codends, and taking a wide variety of fish species (and, no doubt, causing damage to corals they encounter). With the exception of some small pelagic resources for which markets are weak, the status of the various resources ought be assumed as fully exploited.
In the Gulf of Aden, large industrial fisheries using “distant water” factory trawlers based in the area have exploited demersal and small pelagic fish resources in the past, but because of lack of profitability have not functioned for some time. The situation in Somalia remains uncertain with informal reports of fishing companies undertaking operations and also substantial illegal fishing, particularly outside of the Gulf of Aden by foreign operators.
No explicit stock assessment information on the status of the fishery resources is available for this area, and the use of catch data as an indicator of state of exploitation is compromized because the FAO fisheries data base aggregates data from Saudi Arabia for both the Red Sea and Persian Gulf. However, the available data show clearly that the rate of increase in catches by regional countries has declined sharply during the 1990s, being effectively constant over the last few years. Detailed analysis of the data is unwarranted because of the high “estimated” catches for these countries and changing patterns in disaggregation of the data. Increases in different categories may be best explained by increased disaggregation by species in the reported figures.
The small areas available for trawling and absence of any effective regulation in many areas of the Red Sea probably result in fisheries that are quickly fully exploited or overexploited. Markets for fish in the area are strong, particularly in the Yemen and Egypt and for higher-priced species in Saudi Arabia. Low market demand for small pelagics has resulted in reduced fishing for these species, particularly with the withdrawal of East European operators who previously had fished there to supply their home markets.
Coastal East Africa (Somalia to Mozambique)
The east coast of Africa represents a wide range of oceanographic environments and is the site of some of the most dynamically varying large marine ecosystems in the world. The Somali Current develops during the south-west monsoon to become one of the fastest open-ocean current in the world. The coastal upwelling that occurs along the African coast during the intensified phase of the Somali Current is one of the most intense large-scale seasonal coastal upwelling system in the world. Other nearby regions are also strongly influenced by the annually reversing monsoon regime (Tomczak and Godfrey, 1994). However, the region is also puzzling because the coastal fish production seems small for such a large area. The coastal fishery yield along the entire western boundary of the Indian Ocean, including the various island states of the western half of that ocean, represents less than onepercent of the global catches. In spite of this, most of the coastal fish stocks of the region are considered to be fully exploited.
Coastal fisheries production usually far outweighs production from oceanic species such as tunas and generally constitutes around 90–95 percent of total catches, but in the south-western Indian Ocean the contributions of coastal and oceanic fisheries are approximately equal. The Indian Ocean continental shelf off Africa is relatively narrow, and this might provide some explanation for the low coastal catches. However, the disparity in continental shelf area compared to other ocean regions is far less drastic than would be necessary to adequately explain the above anomaly in fish production.
While the coastal fisheries are harvested mostly by coastal states, the more lucrative oceanic fisheries are harvested mostly by distant-water fleets from Europe and eastern Asia. Even so, and despite the low coastal catches, fishing and its associated economic activities are often important to local economies. In some of the south-western Indian Ocean countries, fish are nearly the sole source of animal protein available to the local populations. Moreover, in a region faced with scarcities of foreign exchange, exports of fishery products represent vital sources of exchangeable earnings. The shrimp fishery on the Sofala Bank is important to Mozambique for foreign exchange earnings and similarly for Madagascar. The industrial shrimp fishery in Mozambique is scientifically monitored and actively managed. Recent analyses suggest that the resource is fully exploited and that fishing effort should be reduced. Effort controls should involve not only the number of vessels and seasonal closures, but also the size of the gear used.
REFERENCES
FAO. 2001. Report of the Ad Hoc Meeting on Management of Deepwater Fisheries Resources of the Southern Indian Ocean. Swakopmund, Namibia, 30 May–1 June 2001. FAO Fisheries Report, No.652. 61p.
FAO. 2002. Report of the Second Ad Hoc Meeting on Management of Deepwater Fisheries Resources of the Southern Indian Ocean. Fremantle, Western Australia, 20 – 22 May 2002. FAO Fisheries Report, No. 677. 106p.
Mathews, C.P., Kedidi, S. , Fita, N.I., Al-Yahya, A. & Al Rasheed, K. 1993. Preliminary Assessment of the Effects of the Gulf War on Saudi Arabian Prawn Stocks. Marine Pollution Bulletin, 27:251–272.
Mathews, C.P., Toloday, D. & Ismail, M.S. 1993. Some effects of the 1990–91 Gulf War on Hamoor (Epinephelus tauvina) for the Saudi Arabian Gulf Coast. Asian Fisheries Science, 6: 351–56.
Romanov, E. (ed.) 2003. Summary and Review of Soviet and Ukrainian Scientific and Commercial Fishing Operations on the Underwater Ridges of the Southern Indian Ocean. FAO Fisheries Circular, Rome, FAO. 2003. In print.
Sharp, G.D. 1995. Arabian Sea Fisheries and their Production Contexts. In The Arabian Sea: Living Marine Resources and the Environment. (Eds.) Thompson, M.F. and Tirmizi, N.M. A.A. Balkema, Rotterdam. p. 239–264.
Tomczak, M. & Godfrey, J.S. 1994. Regional Oceanography: An Introduction . Pergamon.pp. 422.
* FAO, Marine Resources Service, Fishery Resources Division
by Purwito Martosubroto *
INTRODUCTION
The Eastern Indian Ocean (Figure B9.1) covers 29.89 million km2 including the Bay of Bengal in the north, the Andaman Sea and northern part of the Malacca Straits in the east, and the waters around the west and south of Australia. The main shelf areas include those of the Bay of Bengal and the Gulf of Martaban and the narrower shelf areas on the western and southern sides of Indonesia and Australia for a total of 2.37 million km2 of shelf area. The main fisheries are coastal and they are concentrated in these shelf areas. The resources range from typical tropical species found in the northern part of the area to temperate species in the waters of the southern latitudes west and south of Australia. The high seas resources, especially tuna, have been mostly exploited by the distant-water fishing fleets from Japan, the Republic of Korea and Taiwan Province of China. The French and Spanish fleets started fishing in the region in 1997 and their catches are smaller than those of the Japanese and Taiwanese fleets.
Figure B9.1 - The Eastern Indian Ocean (Area 57)
In the northern part of the region, north of about 15°S, the fisheries are multispecies and multigear with the concentration of fishing in the inshore area. The fisheries serve as a source of employment and protein supply for a large population. Fishing pressure keeps increasing in the coastal areas off the east of India, the west of Thailand and the east coast of Sumatra facing the Malacca Strait. Knowledge of the fish stocks is generally poor and management actions have usually been taken on an ad hoc basis, in most cases with lack of prior scientific analysis. Poaching is still a problem in this area due to the weakness of monitoring, control and surveillance (MCS) in many coastal states.
Figure B9.2 - Annual nominal catches ('000t) by ISSCAAP species groups in the Eastern Indian Ocean (Area 57)
Source FAO
In the southern part of the region off Australia, fishing pressure on most resources is less intense due to the relatively low population density and local fish demand and to the more active monitoring, control and surveillance, except for high valued fish such as southern bluefin tuna which has also been the target of the distant water fishing fleets.
PROFILE OF CATCHES
Catches in the Eastern Indian Ocean have increased steadily since 1950 (Figure B9.2 and Table D9), and at an accelerated pace since the early 1970s with total catches above 4.0 million tonnes since 1993 and reaching 5.1 million tonnes in 2002. Most of the recent increase in catches was driven almost solely by “marine fish nei” group. Five ISSCAAP fish groups accounted for more than 85 percent of the catches in 2002 with the largest individual contribution (44 percent) being marine fishes not identified (ISSCAAP group 39), an indication of the multispecies nature of the fisheries, particularly in the northern part of the region. Miscellaneous pelagic fishes (ISSCAAP group 37) with 10.4 percent held the second place and miscellaneous coastal fishes at 10 percent (ISSCAAP group 33) held the third one. Tunas, bonitos, and billfishes (ISSCAAP group 36) and Herrings, sardines, and anchovies (ISSCAAP group 35) accounted for 8.7 and 7.9 percent respectively.
Northern areas
Most of the catch from coastal fisheries in the northern areas of the Eastern Indian Ocean is used for local consumption. Fish are generally considered an affordable source of protein by most people in the region. Fisheries are typically multispecies and multigear. The dominance of the group marine fishes not identified (ISSCAAP group 39) in the catch reflects to some extent the weak fishery statistical systems of the countries in the region. Croakers (Sciaenidae), sea catfish nei (Ariidae) and ponyfishes (Leiognathidae) dominated the catch of miscellaneous coastal fishes (ISSCAAP species group 33) and showed continued increase since 1960s, though with fluctuation, (Figure B9.4). Total production of group 33 has been relatively stable for the last 5 years, with catches ranging from 507 000t and 515 000t.
In the herring, sardines and anchovies (ISSCAAP group 35), the catch of anchovy (Stolephorus spp.) and Indian oil sardine (Sardinella longiceps) continued to increase in the 1990s to reach 85 000t for the anchovy in 1998 and 92 000t for the oil sardine in 1997. Since then the catch declined to 20 000t in 2002 for oil sardine while anchovy catches have oscillated between 75 000t and 89 000t in the last five years (Figure B9.4).
The mackerels (Rastrelliger spp.) and other pelagic species dominated the miscellaneous pelagic fishes (ISSCAAP group 37). The catch of Indian mackerel (R. kanagurta) reached a peak of 267 000t in 1995 but declined subsequently, being 207 000t in 2002. Snoek and cutlass fish show an irregular increase with peak catches of 65 000t in 1998. The other miscellaneous demersal group shows a stable catch in the last three years (Figure B9.5). In localized areas, signs of overfishing are obvious. A recent study indicates that during the last decade total catch by trawling in the eastern coast of India has decreased by 41 percent from 31 000t to 18 772t, while the catch rate declined by as much as 61 percent from 48.8 to 18.6 kg per hour of trawling (Vivekanandan, 2002).
Figure B9.3 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 33, Eastern Indian Ocean (Area 57)
Source FAO
Figure B9.4 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 35, Eastern Indian Ocean (Area 57)
Source FAO
Though cephalopods (ISSCAAP group 57) is commercially important, its production is small, with only Thailand producing relatively high catches, nearly 60 000t in the last three years. Some of the Thai fleets have also expanded to fish in other countries through various joint agreements. It is likely that the potential for development of this fishery exists in the region, although further work is still needed in assessing the resources, in addition to the familiarity with the fishing technique.
Although they made a small contribution to catch volumes, shrimps and prawns (ISSCAAP group 45) and tunas, bonitos and billfishes (ISSCAAP group 36) makes a large contribution to the landed and export values. A peak in the shrimp and prawn catch occurred in 2000 with 247 000t before decreasing to 216 000t in 2002. Meanwhile tuna catch reached a peak in 1999 with 516 000t before showing continued decline in the following years. Total catches in 2002 were 447 000t (Figure B9.6). The increase in tuna production during the 1990s was largely contributed to by Indonesia and Sri Lanka. While Thailand experienced a catch decline, the catch by India showed a slight increase as a result of longline fishing that developed in recent years.
Figure B9.5 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 34 & 37, Eastern Indian Ocean (Area 57)
Source FAO
Figure B9.6 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 24, 36, 45, 57, Eastern Indian Ocean (Area 57)
Source FAO
Southern areas
The main fisheries in the southern areas of the Eastern Indian Ocean are off the west and Southwest of Australia. Total catches were 56 800t in 1970 and increased to a peak of 127 800t in 1993, it fluctuated during the following years and finally went down to 110 000t in 2001. This is considerably less than the catches in the northern areas.
The important group in the catches included spiny-lobster, tuna and orange roughy. Lobster catches have been increasing slowly from 6 000t in 1950 to 10–12 000t during the 1980s and 1990s. Catches increased steeply to almost 19 000t in 2000 before decreasing to 13 500t in 2002. The fishery is one of the valuable fishery and it generates export earnings in addition to the tuna fishery. Unlike in the northern part, tuna catches in this area are dominated by southern bluefin tuna. Its catches peaked at 20 000t in 1982, but they have declined since to 2 100t in 1993 before rising again to nearly 5 500t in 2002. However, recent analysis indicates that southern bluefin tuna as being overexploited.
Catches for the herrings, sardine and anchovies (ISSCAAP Group 35) peaked at 17800t in 1988 and subsequently declined to about 9 800t in 1992, then showed slight increase before dropping again to 4 377t in 1999. Total catch of the group has increased since, reaching 14 440t in 2002. It is not clear whether these fluctuations in catches are the result of excessive fishing pressure, to environmental changes or to a combination of both. There were, however, two very large mass mortalities of pilchard throughout southern Australia (and extending up the east and west coasts) in the late 1990s. These events, which may have been caused by a virus introduced in the food used in tuna cages, decimated populations, which are only just now starting to recover.
A similar pattern is seen in the catch of scallops (ISSCAAP Group 55), which showed peaks in 1984 of about 27 000t but in 1989 catches were down to 1 800t. The catch continued to fluctuate and peaked again in 1993 at 27 200t before it declined to 2 525t in 2002. Scallops have tended to show a boom bust cycle over a long period in southern Australia and currently many stocks are currently closed to fishing. Although recruitment events tend to be episodic, there is also evidence for overfishing of individual stocks.
RESOURCE STATUS AND FISHERY MANAGEMENT
Northern areas
Overexploitation of the resources in coastal waters of the northern areas of the Eastern Indian Ocean is very much related to the population pressure in the coastal area, lack of employment opportunities and ineffectiveness of management measures. Current status of exploitation and trend of catch in the region is shown in Table D.9. Zoning scheme of the coastal waters according to fishing gears is quite common in the region (India, Indonesia, Malaysia) and to a certain extent area closures during certain season is popular in Thailand in the management of short mackerels (Rastrelliger spp.). Area closures in association with marine parks are common measures in the case of Malaysia and the Philippines. Insufficient MCS has undermined the implementation of management. FAO, in an effort to assist its member countries, organized a series of workshops in 1999–2001 in Indonesia, Malaysia and Thailand with the financial support of Norway (FISHCODE or GCP/INT/648/NOR) to familiaize the Fisheries Department of those countries with the process of developing management plan for selected fisheries. The exercise encourages participating countries to improve management by promoting more participation of stakeholders in the decision making process. Such assistance is still going on in Indonesia and Thailand for which workshops are scheduled for 2003. The Indonesian Ministry of Marine Affairs and Fisheries has recently made a joint arrangement on fisheries research with the Fisheries Center of the University of British Columbia in an effort to strengthen research capacity in Indonesia with emphasis on ecosystem management.
Overexploitation of penaeid shrimp resources in coastal waters have in fact stimulated the development of aquaculture in many countries in the region. With the limited use or access to waste treatment systems in most countries, organic material and eutrophication seems to be the major aquatic pollution problem. The cyclones that enter the Bay of Bengal are a considerable natural hazard to fishers, particularly given the absence of good weather forecasts and the limited electronic equipment on most fishing vessels. There is a resulting high casualty among fishermen during the cyclone season.
Southern areas
The most valuable fisheries in the southern part includes northern prawn, rock lobster and southern bluefin tuna. Fisheries management in the region falls under the responsibility of the Commonwealth government of Australia and some Australian states/territories (AFMA, 2002). Management of the northern prawn fishery is under the Commonwealth government, while rock lobster is under the state government of Western Australia. The majority of fisheries have been managed by the allocation of fishing rights, either in the form of catch or effort (Caton, 2000). The Commission for the Conservation of Southern Bluefin Tuna (CCSBT) with Australia, Japan and New Zealand as members came into existence in 1994. The Republic of Korea joined the organization in 2001, while fishing entity of Taiwan Province of China has become extended member in 2002. The CCSBT is developing a status of “co-operating non-member” to allow fishing nations to engage with the Commission without becoming full members. This status is expected to take effect in 2003 and Indonesia is expected to be the first country to take advantage of this arrangement (CCSBT, 2003). Meanwhile South Africa has indicated its interest in joining the organization.
High seas
Distant-water fleets from Asia (China, Japan, Republic of Korea and Taiwan Province of China) and Europe (primarily France and Spain) fish in the high seas of the Eastern Indian Ocean. While longline is the main gear for the Asian fleet, purse seine is the main gear for the European fleet. Tunas are the main target species, but sharks are also caught. Japan was leading in the 1960s with a peak of 58 000t in 1967, but it subsequently declined irregularly to 5 000t in 1992, increasing to a peak of 39 400t in 1995 before a decline to 18 000t in 2001 (Figure B9.8). Taiwan Province of China has been fishing in the region since the late 1960s with a first peak of catches at 31 000t in 1986–1987, followed by a trough. Catches have increased steadily from 1991 to 41 000t in 1997, before decreasing to 23 000t in 2000 and 13 000t in 2002. Catches of the Republic of Korea have generally been lower, although they did reach a peak of 19 900t in 1979, but they were only 3 400t in 2002. China started fishing in the area in 1995 and the catch in 2001 reached 4 000t. There had been an increased number of Taiwanese fleets using Phuket (Thailand) and Penang (Malaysia) as a base for their operation. This could be due to the high demand of tuna by the canneries in Thailand in recent years or excellent port facilities for direct export to any destination. In the early 1970s the fleet of the former USSR started fishing in the area, although the catch was less than those of the Asian fleet, their fleet stopped fishing in 1986. The Polish fleet also fished in the area in the late 1980s but made insignificant catch. The French and Spanish fleets began fishing in the area in late 1997. The French fleet landed 10 800t in 1998, 100t in 2000 and reported no catches since, while Spain caught 17 700t in 1998, 200t in 2000 and 1 615t in 2002.
REFERENCES
Australian Fisheries Management Authority (AFMA) 2002. AFMA Annual Reports 2000–2001. Internet address: www.afma.gov.au. Information accessed 10/02/03.
Caton, A. (ed.) 2000 : Fishery Status Reports 2000–2001. Resources Assessments of Australian Commonwealth Fisheries. Bureau of Rural Sciences, Dep. of Agriculture, Fisheries and Forestry: 252p.
Commission for the Conservation of Southern Bluefin Tuna (CCSBT). 2003. Recent news. www.ccsbt.org. Information accessed10/06/03.
Vivekanandan, E. 2002. Multispecies assessment of the demersal fish stocks along the southeast coast of India. Proceedings of the FAO/SEAFDEC regional training workshop on the use of statistics and other information for stock assessment, Samut Prakarn (Thailand), 9–12 September 2002. RAP Publication 2002/27: 24–37.
* FAO, Marine Resources Service, Fishery Resources Division
by Jean-Jacques Maguire *
INTRODUCTION
The Northwest Pacific (Area 61 - Figure B10.1) encompasses a number of distinct extensive areas of productive continental shelf: the northern portion of the South China Sea, the East China Sea, the Yellow Sea, the Sea of Japan (East Sea) and the Sea of Okhotsk. Other subareas have less extensive continental shelf areas but are nevertheless sites of productive fisheries; these include the western portion of the Bering Sea and also the zones of ocean adjacent to the eastern edges of the Ryukyu Islands, Japan, the Kuril Islands, and the south-eastern part of the Kamchatka Peninsula where interactions and confluences of swift western ocean boundary currents produce zones of enrichment and concentration of biological processes. The total surface area is close to 19million km2, with the third largest shelf area at about 3.6 million km2.
Figure B10.1 - The Northwest Pacific (Area 61)
After a general decline from 1988 to 1993–1994, nominal catches have subsequently increased to 1997–98, surpassing very slightly the previous peak, making the Northwest Pacific the most productive FAO area with almost 25 tonnes reported. Nominal catches declined to 24 million tonnes in 1999 and to 21 million in 2002. There continues to be concern over the increasing fishing effort in the Northwest Pacific.
Figure B10.2 - Annual nominal catches ('000 t) by ISSCAAP species groups in the Northwest Pacific (Area 61)
PROFILE OF CATCHES
Total catches in the area grew steadily from about 4 million tonnes in 1950 to an intermediate peak of 24.5 million tonnes in 1988 (Figure B10.2 and Table D10). Catches declined to 20.4 million tonnes in 1994 because of abrupt decreases in the two fish species that had been by far the most abundant, the Japanese pilchard in ISSCAAP group 35 and the Alaska pollock in ISSCAAP group 32. The declines in these two extremely abundant species have been offset by increases in production of other major species, such that in 1997–1998, catches by capture fisheries exceeded the earlier 1988 peak total (Figure B10.2) but they have decreased since to 21.4 million tonnes in 2002. The Japanese pilchard (or sardine) (Sardinops melanostictus) population in 1988 produced peak catches of 5.4 million tonnes but by 1998 the catches had fallen to 296 000t and they have remained of that order since (Figure B10.3). Traditionally the largest catches have been produced by extremely large regional fishery, that on the Alaska pollock (Theragra chalcogramma ), but also abruptlydeclined from its 1988 peak of 5.1 million tonnes to a low of 1.1 million tonnes in 2002 (Figure B10.3). The decline of the pollock is thought to be related to excessive fishing pressure, although the evidence suggests at least some environmental component. However, it is believed that the sardine collapse have been primarily due to some sort of natural ecosystem variability.
Figure B10.3 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 35 & 37, Northwest Pacific (Area 61)
Source FAO
Figure B10.4 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 32 & 34, Northwest Pacific (Area 61)
Source FAO
Figure B10.5 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 55, 56, 57, Northwest Pacific (Area 61)
Source FAO
The primary harvest area of Alaska pollock is the Sea of Okhotsk. The next most important region for pollock exploitation is the broad shelf area from the western Bering Sea to the east coast of Kamchatka. Japan takes significant amounts in the Japan Sea and the Republic of Korea takes a small amount.
Japanese anchovy (Engraulis japonicus ) (Figure B10.3) increased from 0.3 million tonnes in 1988 to more than 2 million tonnes in 1998 before declining to around 1.8 million tonnes in 1999–2002. Largehead hairtail (Trichiurus lepturus) (Figure B10.4) increased from 0.53 million tonnes in 1988 to almost 1.4 million tonnes in 2000–2002, chub mackerel (Scomber japonicus) (Figure B10.3) decreased from 1.6 million tonnes in 1996 to 0.87 million tonnes in 2002. ISCAAP group 57 (squid, cuttlefish, octopuses) have increased steadily for the last 15–20 years, largely influenced by catches of Japanese flying squid, those of ISCAAP group 56 (clams, cockles, arkshells) have slowly declined, while those of Yesso scallops have steadily increased (Figure B10.5)
Pacific herring (Clupea pallasii) catches (Figure B10.3) have been in a multi-decadal downward trend until the early 1990s, with the 1994 catches being only about one-fourth of the average for the decades of the 1960s and 1970s. However, after 1994 catches increased to a peak of 433 000t in 1998 and have been decreasing since to 255 000t in 2002.
Pacific cod (Gadus macrocephalus) catches have followed the general pattern of the pollock and other North Pacific groundfish in declining from the 1980s (Figure B10.4). The highest abundance in Area 61 appears to be in the Russian Navarin area of the Northern Bering Sea. Also it is possible that abundance may be higher in the Sea of Okhotsk than indicated by catches because of trawling closures designed to protect king crab (Lithodes ferox ).
The general trend of salmon catches over the past two decades has been upwards. The major salmon species in the northwestern Pacific are the Chum salmon (Oncorhynchus keta ), which since the 1970s ordinarily produces the largest catches, and the Pink salmon (Oncorhynchus gorbuscha ). The catches of Chum salmon have declined from 297 000t in 1996 to 175 000t in 2000 but increased in 2001–2002 to over 220 000t. The pink salmon catches peaked in 1991 (Figure B10.6), declined abruptly in 1992, increased again to 201 000t in 1998 but have been generally decreasing since.
The catches of shrimps and prawns have been increasing strikingly in the region over the past three decades (Figure B10.7).
RESOURCE STATUS AND FISHERY MANAGEMENT
As mentioned above, the largest marine resource variations in the region have concerned the pilchard (or sardine) population. The sardine fishery off Japan grew rapidly in the 1930s to become the largest single-species fishery existing in the world at that time. Then in the early 1940s the population abruptly collapsed. It remained depleted for nearly three decades and then suddenly exploded in the mid-1970s into a rapid rebuilding phase (Kawasaki, 1983) that led in the 1980s to catches more than twice the peak catches before the earlier collapse. Now the population, after sustaining major fishery exploitation for a length of time quite similar to that of the earlier fishery, has gone into rapid decline a second time (Figure B10.3). It is believed that the fluctuations in sardine abundance are not mainly the result of fishing but rather are governed by ecosystem changes which may be related to climate variation (Lluch-Belda et al., 1989, 1992; Bakun, 1996, 1998; Schwartzlose et al., 1999; Cury et al., 2000; Csirke and Vasconcellos, this volume).
The decline in sardine catches has been accompanied by a strong rebound of Japanese anchovy catches (Figure B10.3). This follows a strong pattern of alternation of sardine and anchovy stocks in many regions throughout the world (Lluch-Belda et al., 1989, 1992; Bakun, 1998; Schwartzlose et al., 1999). In addition to large catches off Japan, Japanese anchovy has also taken over, after heavy fishery removals of demersals and larger predatory fishes, as the largest catch in both the Yellow Sea (Tang and Jin, 1999) and the East China Sea.
The overexploited state of the Alaska pollock fishery is becoming more and more apparent, and there is a continuing trend toward an increasing portion of younger year classes of pollock and of low value, undifferentiated fish of other species in the catches. All the major pollock stocks are believed to be currently at substantially lower biomass than existed in the 1980s and there are forecasts of catch trends continuing downwards for several years into the future. The unregulated fisheries that produced very high catches in the late 1980s and early 1990s in the international waters of the “Doughnut Hole” and “Peanut Hole” have been curtailed, but there remains concern with the Okhotsk “banana”.
In recent years, the stocks of Japanese flying squid, are believed to be fluctuating at intermediate to high biomasses and they are considered moderately to fully exploited.
Figure B10.6 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 23, Northwest Pacific (Area 61)
Source FAO
Figure B10.7 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 42, 45, Northwest Pacific (Area 61)
Source FAO
Fishing effort in the region has continued to rise. For example, in the East China Sea the total fishing power of Chinese vessels increased by a factor of about 7.6 between the 1960s and 1990s, catch per unit of effort declined over the same period by a factor of 3. In coastal seas such as the East China and Yellow Seas, there has been a shift in catches from large high-valued fish to lower-valued smaller fishes, from demersal and pelagic predator fishes to pelagic plankton-feeding fishes, from larger to smaller individuals (Tang and Jin, 1999; Zhang, Kim and Huh, 1988; Zhang and Kim, 1999). Reduction of fishing effort in some areas is considered urgent (e.g. Chen and Shen, 1999; Zhang, Kim and Yun, 1992)
Environmental problems affecting fisheries in the region include land reclamation, heavy metal pollution (She, 1999), oil spills, and impacts of extensive mariculture. There appears to be an increasing frequency of red tides (She, 1999). In the Yellow Sea, bacterial epidemics are causing mortality of cultured shrimp. The Sea of Okhotsk is the site of frequent earthquakes and the oil drilling that is poised to begin is cause for concern because of the high risk of oil spills.
REFERENCES
Bakun, A. 1996. Patterns in the Ocean: Ocean Processes and Marine Population Dynamics. University of California Sea Grant, San Diego, California, USA, in co-operation with Centro de Investigaciones Biológicas de Noroeste, La Paz, Baja California Sur, Mexico. 323 pp.
Bakun, A. 1998. Ocean Triads and Radical Interdecadal Stock Variability: Bane and Boon for Fishery Management Science. p. 331–358. In T.J. Pitcher, P.J.B. Hart and D. Pauly (eds.) Reinventing Fisheries Management . Chapman and Hall, London.
Chen, Y.-Q. & Shen, X.-Q. 1999. Changes in the biomass of the east China sea ecosystem. p. 221–239. In K. Sherman and Q. Tang (eds.) Large Marine Ecosystems of the Pacific Rim: Assessment, Sustainability and Management . Blackwell Science Inc. Malden, Massachusetts. 465 pp.
Cury, P., Bakun, A., Crawford, R.J.M., Jarre-Teichmann, A., Quiñones, R.A., Shannon, L.J. & Verheye, H. M. 2000. Small pelagics in upwelling systems: patterns of interaction and structural changes in “wasp-waist” ecosystems. ICES J. Mar. Sci. 57(3): 603–618.
Kawasaki, T. 1983. Why do some pelagic fishes have wide fluctuations in their numbers? - biological basis of fluctuation from the viewpoint of evolutionary ecology. p. 1065–1080. In G.D. Sharp and J. Csirke (eds.) Reports of the Expert Consultation to Examine Changes in Abundance and Species Composition of Neritic Fish Resources. FAO Fisheries Report, No. 291(3). 1224 pp.
Lluch-Belda, D., Crawford, R.J.M., Kawasaki, T., MacCall, A.D., Parrish, R.H., Schwartzlose R.A. & Smith, P.E. 1989. World-wide fluctuations of sardine and anchovy stocks: the regime problem. S. Afr. J. mar. Sci., 8: 195–205.
Lluch-Belda, D., Schwartzlose, R.A., Serra, R., Parrish, R.H., Kawasaki, T., Hedgecock, D., & Crawford, R.J.M. 1992. Sardine and anchovy regime fluctuations of abundance in four regions of the world oceans: a workshop report. Fish. Oceanogr., 1: 339–347.
Schwartzlose, R.A., Alheit, J., Bakun, A., Baumgartner, T., Cloete, R., Crawford, R.J.M., Fletcher, W.J., Green-ruiz, Y., Hagen, E., Kawasaki, T., Lluch-Belda, D., Lluch-Cota, S.E., MacCall, A.D., Matsuura, Y., Nevarez-Martinez, M.O., Parrish, R.H., Roy, C., Serra, R., Shust, K.V., Ward , N.M. & Zuzunaga, J.Z. 1999. World-wide large-scale fluctuations of sardine and anchovy populations. S. Afr. J. Mar. Sci . 21: 289–347.
She, J. 1999. Pollution in the Yellow Sea Large Marine Ecosystem. pp. 419–426. In K. Sherman and Q. Tang (eds.) Large Marine Ecosystems of the Pacific Rim: Assessment, Sustainability and Management . Blackwell Science Inc. Malden, Massachusetts. 465 pp.
Tang, Q. & Jin, X. 1999. Ecology and variability of economically important pelagic fishes in the Yellow Sea and Bohai Sea. pp. 179–198. In K. Sherman and Q. Tang (eds.) Large Marine Ecosystems of the Pacific Rim: Assessment, Sustainability and Management. Blackwell Science Inc. Malden, Massachusetts. 465 pp.
Zhang, C.I., Kim, J.M., & Huh, H.T. 1988. Current status of fisheries resources and their rational management in the Yellow and East China Seas. In Y. B. Go (ed.) Proceedings of Symposium on Development of Marine Resources and International Cooperation in the Yellow Sea and East China Sea, Cheju, Korea, 19–22 October 1988:71–96.
Zhang, C.I. & Kim, S. 1999. Living marine resources of the Yellow Sea ecosystem in Korean waters: status and perspectives. pp. 163–178. In K. Sherman and Q. Tang (eds.) Large Marine Ecosystems of the Pacific Rim: Assessment, Sustainability and Management. Blackwell Science Inc. Malden, Massachusetts. 465 pp.
Zhang, C.I., Kim, S., & Yun, S.B. 1992. Stock assessment and management implications of small yellow croaker in Korean waters. Bull. Korean Fish. Soc., 25(4): 280–290.
* FAO consultant, Marine Resources Service, Fishery Resources Division
by Jean-Jacques Maguire *
INTRODUCTION
The Northeast Pacific (Figure B11.1) covers close to 9 million km2, of which 1.3 million km2are shelf area. It encompasses several distinct “Large Marine Ecosystems”, including the northern portion of the California Current region, the Gulf of Alaska, and the eastern part of the Bering Sea. These subareas embody distinct environmental dynamics: the California Current is a classic subtropical eastern ocean upwelling system while the subarctic system of the Gulf of Alaska and Bering Sea, dominated by the Aleutian Low pressure cell, is one of the most intense, quasi-permanent atmospheric systems on earth. In the Gulf of Alaska, the result is intense coastal convergence which drives anti-clockwise coastal flow around the periphery of the Gulf which interacts with coastal runoff to produce embedded frontal zones of concentration of biological processes. The eastern Bering Sea is a shallow shelf system, characterized by tidal mixing and related shelf-sea frontal formations.
Figure B11.1 - The Northeast Pacific (Area 67)
PROFILE OF CATCHES
Total nominal catches for the Northeast Pacific increased from 618 000t in 1950 to slightly above 3.4 million tonnes in 1987. Catches have generally declined since and they were 2.7 million tonnes in 2002 (Figure B11.2 and Table D11). Alaska (walleye) pollock (Theragra chalcogramma) has accounted for the largest part of the catches since the early 1970s, between 40–50 percent of the total for most of that period (Figure B11.2). Catches of Alaska pollock have declined from 1.7 million tonnes in 1987 to 1.0 million tonnes in 1999 before increasing to 1.5 million tonnes in 2002 (Figure B11.3). Traditionally, ISSCAAP Group 23 (salmons, trouts, smelts) has accounted for the second largest contribution. Interestingly, this is one of the few areas where ISSCAAP Group 35 (herrings, sardines, anchovies) does not make a large contribution to catches.
Figure B11.2 - Annual nominal catches ('000t) by ISSCAAP species groups in the Northeast Pacific (Area 67)
Salmon catches in Area 67 have exhibited a strong increasing trend from the mid-1970s to the mid 1990s (Figure B11.4) mainly due to stock occurring in the northern portion of the region. However, the opposite is generally true for the coho (Oncorhynchus kisutch) and Chinook (Oncorhynchus tshawytscha) salmon stocks.
The largest flatfish stock in the area is the Bering Sea yellowfin sole (Pleuronectes asper ). This fishery followed a pattern similar to that of the salmon and gadoids in increasing rapidly during the 1970s and early 1980s (Figure B11.5), and declining afterwards. Halibut catches have remained relatively stable without trend.
Catches of ISSCAAP Group 32 (cods, hakes, haddocks) and 34 (misc. demersal fishes) species are highly irregular, except for sablefish whose catches have been slowly declining and Pacific cod where they have increased steeply since the late 1970s and varied between 210 000t and 250 000t in recent years (Figure B11.6). The Pacific Ocean Perch supported an important fishery in the 1960s, but since 1980, catches have been a small fraction of those reported in the 1960s and early 1970s, although they have consistently exceeded 20 000t since 1990.
King crab (Lithodes ferox) catches dominated ISSCAAP Group 42 (sea-spiders, crabs) species from the early 1960s to the mid 1970s, but snow crab (Chionocetes opilio) catches were about equal and following a similar pattern from the mid 1970s to the mid 1980s. Since the mid 1980s, king crab catches have remained low, while those of the other sea-spiders and crabs (mostly snow crab) show wide fluctuations. The 2001 catches for Chionocetes spp. were the lowest since 1971 and in 2002 it remained under 40 000t.
Figure B11.3 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 32, Northeast Pacific (Area 67)
Source FAO
Catches of Pacific herring (Clupea pallasii) have been relatively stable at between 60 000t and 100 000t since 1980 (Figure B11.7), showing a slight declining trend. The California sardine fishery in this area had essentially collapsed before FAO statistics began to be collected. Sardine catches have increased from almost zero during 1950 to 1999 to 14 000t in 2000 and 39 000t in 2002.
RESOURCE STATUS AND FISHERY MANAGEMENT
Salmon resources
The salmon population increases during most of the 1980s and 1990s in Alaska were attributed to favourable ocean conditions allowing high survival of juveniles (NMFS, 1999), as well as to several other factors including (1) improved management, (2) elimination of high sea driftnet fisheries, (3) reduction in bycatch in fisheries for other species, and (4) relatively pristine river habitats with minimal influence of extensive development.
Figure B11.4 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 23, Northeast Pacific (Area 67)
Source FAO
Figure B11.5 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 31, Northeast Pacific (Area 67)
Source FAO
Salmon stocks face increasing pressure from environmental problems. Many of the stocks, particularly those in the southern part of the region, are already severely impacted. Being anadromous spawners, salmon reproduction is strongly affected by riverine and estuarine habitat degradation caused by logging, mining, oil and gas development, industrial development and urban expansion. Resulting conflicts with other economic sectors make mitigation difficult. There is also concern that use of hatchery production to help compensate for habitat loss may lead to the destruction of wild stocks (Hilborn and Eggers, 2000).
Figure B11.6 - Annual nominal catches ('000t) of selected species in ISSCAAP Groups 32 & 34, Northeast Pacific (Area 67)
Source FAO
Figure B11.7 - Annual nominal catches ('000t) of selected species in ISSCAAP Group 35, Northeast Pacific (Area 67)
Source FAO
Damming of rivers for hydroelectric power development, water storage, and flood control has historically done great damage to salmon runs. An example is the extensively dammed Snake River basin of Washington State, where wild salmon have declined nearly 90 percent in the past thirty years, and every population has either been driven to extinction or is shielded by the United States Endangered Species Act.
Production of Pacific salmon (Oncorhynchus spp.) is expected to remain below average, in conjunction with large-scale climate indicators that appear to have changed trends in 1998. From 1999 to 2001 the total catches of Pacific salmon in Canada were the lowest on record (starting in 1925). The modest increase in catches in 2002 (33 000t) could be an indication that the productivity of Pacific salmon is improving in the southern range of their distribution. It is important to note that large escapements were recorded in 2001 for a number of species. For example, the escapement of pink salmon (O.gorbuscha) to the Fraser River was twice the highest recorded and generally improved throughout British Columbia. Sockeye (O. nerka) escapements in Barkley Sound were the highest recorded. Many coho (O. kisutch) stocks along the coast also had exceptional escapements. Sockeye returns to the Fraser River in 2002 were much higher than forecast. Thus, it appears that climate and productivity conditions have improved for all species of salmon on the west coast of Canada.
Groundfish resources
Many of the most important groundfish stocks of the North Pacific followed the same pattern of rapid increase, beginning in the mid-1970s, that marked the large salmon stocks of the subarctic Pacific area (Bakun, 1996, 1999). Accordingly the largest groundfish population of them all, the complex of Alaska pollock stocks distributed over the breadth of the subarctic Pacific, both the Northeast (Area 67) and Northwest portions (Area 61), during much of the 1980s, held the distinction of being the largest exploited groundfish population in the world. The Alaska pollock is considered to be fully utilized in this region.
The other large gadoid populations in the area, Pacific cod and Pacific whiting (Merluccius productus) (also known as Pacific hake) have followed a similar pattern, rising from the mid-1970s to mid-1980s. Pacific cod are fully utilized in both the Bering Sea and the Gulf of Alaska. Pacific whiting is considered to be fully utilized. While the largest stock of Pacific cod is in the Bering Sea, Pacific hake is concentrated in the area off the United States and Canadian west coasts and contrary to the Pacific cod, Pacific hake abundance apparently is continuing to decline (Anon., 1999).
Of the important flatfish populations, the very valuable Pacific halibut (Hippoglossus stenolepis) resource is considered to be fully utilized and the exploitable biomass has been above average and stable for the last 4–5 years. In general, the resource is considered healthy (Clark and Hare, 2002) and catches have been near historical record highs since 1997 (Figure B11.5). Both Canadian and Alaskan fisheries have moved to an “individual fishing quota” fishery.
Yellowfin sole (Pleuronectes asper ) is considered to be under-utilized. Flatfish other than halibut and yellowfin sole are abundant and are under-utilized in the Bering Sea and Gulf of Alaska due to bycatch restrictions. Black halibut (Reinhardtius hippoglossoides) is the only flatfish stock that is currently below target abundance, having declined rather steadily, due to poor reproductive success, from high biomasses in the early 1980s.
Sablefish (Anoplopoma fimbria) is fully utilized throughout the region.
In general, commercial groundfish stocks off the west coast of Canada are considered to be at low to average abundance. Pacific cod and Pacific hake continue at very low abundance. Exploitable stocks of rockfishes, flatfishes, lingcod (Ophiodon elongatus ), and pollock range from low to moderate. Sablefish remains below the long term average. Recent climate/ocean conditions may result in improved recruitment of many groundfish stocks (McFarlane, 2002). During the 1990's several groundfish species experienced reduced year class success (McFarlane et al., 2000). However, even if year class success since 1999 is improved, increased exploitable biomass will not be seen until those cohorts enter the fishery. For sablefish, Pacific hake, Pacific cod, and flatfish species this could occur after 2004, and for rockfish after 2009.
There are over 80 species of groundfish in the Pacific Fishery Management Council (PFMC) Groundfish Fishery Management Plan (FMP).These species include over 60 species of rockfish in the family Scorpaenidae, 7 roundfish species, 12 flatfish species, assorted shark, skate, and a few miscellaneous bottom-dwelling marine fish species. Based on the Groundfish FMP's standards for defining overfished groundfish species, nine groundfish species have been declared overfished by NMFS in the area of the PFMC: bocaccio rockfish (Sebastes paucispinis ), canary rockfish (S.pinniger ), cowcod (S.levis ), darkblotched rockfish (S.crameri ), lingcod (Ophiodon elongatus ), Pacific Ocean perch (S.alutus ), North Pacific hake (Merluccius productus ), widow rockfish (S.entomelas ) and yelloweye rockfish (S.ruberrimus ).
Small pelagics
Pacific herring support an extremely valuable fishery, much of it for high-valued roe destined to the Japanese market. In general, since the mid-1970s, herring seem to be fluctuating at low to moderate abundance. The abundance trends vary among the numerous stocks in the region, but overall, the very recent trend is for fairly healthy abundance (NMFS, 1999). The abundance of Pacific herring in the Strait of Georgia in 2002 was considerably stronger than recent years at well over 100 000t. Current abundance is second only to the historical high of 1955 (140 000t) and well above the lowest abundance estimated in 1968 (11 000t) in the time series from 1951–2002. The abundance of this stock has been increasing steadily since the recent low of the mid-1980s. Juvenile surveys suggest the trend of recent strong recruitment is likely to continue at least over the next few years. Herring on the west coast of Vancouver Island are likely to increase given the reduction in the abundance of predators in the area. Since conditions were more favourable for herring survival in 2000 and 2001, an improvement in recruitment to the stock in 2003 is expected. Herring stocks in the Hecate Strait area consist of migratory stocks from the Queen Charlotte Islands, Prince Rupert and central coast areas. For the past ten years, recruitment and abundance of the Queen Charlotte Island stock has been low while recruitment and abundance of the Prince Rupert and Central Coast stocks have been generally good. Recently, survival conditions have deteriorated in the Central Coast but have improved in the Prince Rupert and Queen Charlotte Island regions. Abundance is therefore expected to increase in the Queen Charlotte Island and Prince Rupert regions, and decline in the Central Coast region.
Invertebrates
Crab and shrimp biomasses are low throughout Alaska. The red king (Paralithodes camtschatica) and Tanner crab (Chionoecetes bairdi ) stocks are particularly low. The bycatch of crabs in trawl and pot fisheries continues to be a major issue (NMFS, 1999).
In Canadian waters, catches and landed value of shellfish continue to increase as new species are added to the list of commercial fisheries. Northern abalone (Haliotis kamtshatkana) populations are at low abundance, with no sign of recovery after the fishery closed in 1990. Geoduck clam (Panopea abrupta ) populations appear to be increasing due to higher than average recruitment in the 1990s. Catches of intertidal clams (Venerupis philippinarum, Protothaca staminea, Saxidomus gigantea) have declined, but the declines are due to loss of traditional fishing locations to contamination or aquaculture, not decreased abundance. Razor clam (Siliqua patula) abundance on Graham Island in the Queen Charlotte Islands increased in the late 1990s and early 2000s. Abundance trends for spiny and pink scallops (Chlamys hastata and C. rubida) are unknown as there is no available historic distribution and abundance information. Dungeness crab (Cancer magister) populations in the Queen Charlotte Islands continue to decline from historic highs early 1990s, while stocks elsewhere on the British Columbia coast are relatively stable at near average. Changing effort patterns and selective targeting by size and species in the mixed-species trawl fishery for shrimp (Pandalus and Pandalopsis spp.) has led to concerns of local stock depletion. Pink shrimp (Pandalus jordani) stocks off the west coast of Vancouver Island are declining from a recent period of high abundance. Numerous small, local stocks of prawn (Pandalus platyceros) exhibit mixed trends, with no overall trend apparent. Green sea urchin (Strongylocentrotus droebachiensis ) landings have stabilized and CPUE is increasing in the fishery, indicating that abundance is increasing. Red sea urchin (Strongylocentrotus franciscanus ) stocks are reasonably stable with several small areas closed to fishing due to poor local recruitment and or predation by sea otters. Red sea cucumber (Parastichopus californicus) populations are stable or increasing in areas where commercial harvest occurs. Abundance trends for minor commercial species, such as gooseneck barnacles (Policipes polymerus ), opal squid (Loligo opalescens) and Tanner crab (Chionoecetes tanneri) are unknown.
REFERENCES
Anon. 1999. 1998 whiting fishery and 1999 outlook. Pacific Whiting Conservation Cooperative Newsletter. Pacific Whiting Conservation Cooperative. Seattle.
Bakun, A. 1996. Patterns in the Ocean: Ocean Processes and Marine Population Dynamics. University of California Sea Grant, San Diego, California, USA, in cooperation with Centro de Investigaciones Biológicas de Noroeste, La Paz, Baja California Sur, Mexico. 323 pp.
Bakun, A. 1999. A dynamical scenario for simultaneous “regime-scale” marine population shifts in widely separated large marine ecosystems of the Pacific. p. 2–26. In K. Sherman and Q. Tang (eds.) Large Marine Ecosystems of the Pacific Rim: Assessment, Sustainability and Management . Blackwell Science Inc. Malden, Massachusetts. 465p.
Clark, W.G. & Hare, S.R. 2002. Assessment of the Pacific Halibut Stock at the end of 2002. IPHC report, 26 pp. (http://www.iphc.washington.edu/halcom/research/sa/papers/sa02.pdf)
Hilborn, R. & Eggers, D. 2000. A review of the hatchery programs for pink salmon in Prince William Sound and Kodiak Island, Alaska. Trans. Am. Fish. Soc . 129: 333–350.
McFarlane, G.A., King, J.R., & Beamish, R.J. 2000. Have there been recent changes in climate? Ask the fish. Prog. Oceanog . 47 (2000): 147–169.
McFarlane, G.A. 2002. 2001 Pacific Region state of the ocean - report of the Fisheries Oceanography Working Group. Can. Tech. Rep. Fish. Aquat. Sci . 2423: 69p.
McFarlane G.A. 2003. 2002 Pacific Region state of the ocean - report of the Fisheries Oceanography Working Group.
NMFS. 1999. Our living oceans. Report on the status of U.S. living marine resources, 1999. U.S. Department of Commerce, NOAA Technical Memorandum. NMFS-F/SPO-41. 301p.
* FAO consultant, Marine Resources Service, Fisheries Resources Division
