Marine resources - Southeast Atlantic|
Fact Sheet Title Fact Sheet |
| | Marine resources - Southeast Atlantic |
| Data Ownership | This document owned by Food and Agriculture Organization (FAO), provided and maintained by Marine and Inland Fisheries Branch (FIRF) , is part of FAO Global Marine Fishery Resource Reports data collection. |
| ident Block | ident Block | | Species List: All aquatic species | |
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| ident Block Marine resources - Southeast Atlantic Aq Res Ident Aq Res Ident Aq Res Ident fao Major |
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47 | Atlantic, Southeast |
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| Aq Res | Biological Stock: Biological Stock
Value: Regional Management Unit: Management Unit
Reference Year: 2009
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Considered a management unit: An aquatic resource or fishery is
declared as [Fishery] Management Unit if it is
effectively the focus for the application of selected
management methods and measures, within the broader
framework of a management system. According to the FAO
Glossary for Responsible Fishing, "a Fishery Management
Unit (FMU) is a fishery or a portion of a fishery
identified in a Fishery Management Plan (FMP) relevant
to the FMP's management objectives." FMU's may be
organised around fisheries biological, geographic,
economic, technical, social or ecological dimensions ,
and the makeup and attribute of a fishery management
unit depends mainly on the FMP's management
objectives. |
Jurisdictional distribution: Jurisdictional qualifier (e.g.
"shared", "shared - highly migratory") of the aquatic
resource related with its spatial distribution. |
Environmental group: Classification of the aquatic
resource according to the environmental group (e.g.
pelagic invertebrate, or demersal fish) to which the
species belong. |
| | | | Aq Res State Trend To access all FIRMS State and Trend summaries available for this Area, please look at: Status and Trend Summaries (extracted from reports)Most of the commercially important stocks within the region are classified as being between fully exploited and overexploited (Table D7). The stocks that are currently overexploited are frequently, but not always, a result of historical overexploitation rather than current overfishing. Small pelagic fishThe commercially important small pelagic stocks in all three countries are closely monitored, both by recording commercial landings and by making use of regular hydroacoustic surveys. In South Africa, the stocks of pilchard and anchovy are managed on the basis of formal management procedures, which have negotiated decision rules developed using rigorous simulation models of the fishery (Cochrane, Butterworth and Payne, 1997; De Oliveira et al., 1998). In Angola and Namibia, these stocks are managed under a licence and TAC system that adjusts allowable catch annually depending on the analyses of stock status. 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. Pilchard, South Africa The November 2002 survey found the highest peak in the estimated biomass of South African stock of Southern African pilchard (Sardinops sagax) since surveys started in 1985. The biomass estimated on that hydroacoustic survey exceeded 4 million tonnes. However, the estimated biomass has declined to less than 500 000 tonnes in the period since 2006. In the northern part of Area 47, north of the Lüderitz upwelling cell, the estimated biomasses have shown a clear increase in the most recent surveys. This is probably mainly the result of good recruitment from the 2008–09 spawning season and relatively higher survival of the adults. The improved biological conditions have been supported by a strict control on landings imposed by Namibia and Angola. However, the biomass is still at a very low level compared with the historical abundance. Anchovy, South Africa The South African stock of anchovy is in a healthy condition. The biomass estimated in the November 2009 survey was 3.8 million tonnes, close to the maximum values observed since acoustic surveys for this species began. Fishing for Whitehead’s round herring, which occurs mainly in South Africa, is not directly regulated at present. Recent assessments have suggested that it is being underexploited. However, with the recent increases in landings of the species, this approach is currently being re-examined. Sardinella, Angola The biomass estimates for Angolan waters of the two species of sardinella combined has shown a recovery from the 1990s. There was a period of substantial variability in the 2000s, with a minimum of about 250 000 tonnes in 2005 and a maximum of about 700 000 tonnes in 2007. Recently, landings have fluctuated about 500 000 tonnes, without any clear trend. In the late 1990s, flat sardinella dominated the landings and the estimated biomass. However, this situation was reversed in 2004, and the most recent acoustic surveys off Angola in March/April 2011 indicated that round sardinella represents about 60 percent of total biomass (INIP, 2011). The latest assessments indicate that the stocks of these two species are probably not fully exploited. However, there is a need for continuing monitoring of these stocks, particularly in view of the uncertainty about the magnitude of landings taken by the artisanal fisheries and the fast growth of this subsector since 2002 (INIP, 2011). Cape horse mackerel, Southeast Atlantic The stock structure of the Cape horse mackerel population of the Southeast Atlantic (Area 47) is not clear. For management purposes, horse mackerel are treated in the same way as sardine, with the stock from southern Angola and Namibia separated from that of South Africa 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, the individuals captured by the existing fishery tend to be appreciably smaller than those landed in the period of high landings in the 1950s, warranting some care in its management. The northern stock is an important contributor to the national fishery of Namibia, where it is fished by mid-water trawl and a purse-seine fleet. In Angola, since 2007, only purse seines are allowed to target horse mackerel. The abundance of this stock has been fluctuating appreciably. In Namibia, an all-time-low stock biomass of about 500 000 tonnes was estimated in 2007, but this recovered to more than 1.2 million tonnes in 2009 and 2010. The stock is currently considered to be fully exploited (MFMR, 2010). Cunene Horse mackerel, North of Angola-Benguela front The Cunene horse mackerel is the most important pelagic species north of the Angola–Benguela front. This is not only in total biomass, but also owing to its importance as food for the Angolan population. 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. However, recent survey estimates indicate a drastic decrease in biomass, particularly affecting the adult part of the population, to as low as 60 000 tonnes in 2008 (INIP, 2011) Commercial vessels could not catch their Cunene horse mackerel quota in 2009. The latest assessments indicate a state of severe growth overfishing, but good recruitment was still visible in the surveys (INIP, 2011). A total ban on targeted fishing of Cunene horse mackerel came into force in 2010. This ban was partially lifted in 2011, but the state of the stock and the fishery is very closely monitored (INIP, 2011). Large pelagic fishTuna and Tuna-like species, Southeast Atlantic Fisheries targeting tuna and tuna-like species (ISSCAAP Group 36) are also important in Area 47. These species attract several distant-water fishing nations in addition to participation by the coastal States. Large pelagic species caught include bigeye tuna (Thunnus obesus), albacore (Thunnus alalunga), swordfish (Xiphias gladius), southern bluefin tuna (Thunnus maccoyii) and a number of other species. Both Namibia and South Africa have developed draft national plans of action (NPOAs) in accordance with the IPOA-Sharks, and Angola is preparing its National Plan. The ICCAT is responsible for the assessment of these species and stocks and for the management of fisheries exploiting them. These stocks are discussed in Chapter C2 of this report. Demersal fishCape Hakes, Southeast Atlantic The Cape hakes are found in Namibia and South Africa, and Benguela hake (M. polli) occurs north of the Cunene River, the border between Namibia and Angola. Each State manages the fisheries occurring in its own EEZ. The shallow-water Cape hake (M. capensis) dominates the landings from Namibia, and is still dominant in landings from the south coast of South Africa. The deep-water Cape hake (M. paradoxus) is an increasingly important component of landings from Namibia and dominates landings from South Africa’s west coast. However, the two species are not identified separately in commercial landings. Until recently, South Africa assessed the two as a single stock because of difficulties in separating the two Cape hake species in commercial landings (Payne and Punt, 1995). However, separate assessments are now being undertaken. Recent assessments indicate that the stock of M. capensis in South African waters can be considered as fully exploited, while that of M. paradoxus is strongly overexploited (DAFF, 2011). The assessments in Namibia are currently undertaken on both species combined and make use of commercial CPUE information and the results of research surveys. Survey results in the past decade have shown little overall trend. However, following a peak in 1998, there was a decline in survey estimates of biomass until 2004. The introduction of drastic management measures in 2006 included important TAC cuts. These measures have probably helped the stock make the best use of the strong M. capensis 2002–04 and 2007 year classes. By 2008–09, the hake biomass (the two species combined) was estimated to be more than 1 million tonnes (MFMR, 2010). Benguela hake is captured in Angola, mostly as bycatch of the important deep-sea shrimp fishery. Catch rates and survey abundance estimates have declined strongly since 2004. The stock is now considered to be overexploited, although not yet drastically so (INIP, 2011). Other demersal fish, Southeast Atlantic Demersal and coastal fisheries in the region exploit a wide range of species that vary markedly in a north–south gradient. Off Angola, the species composition of demersal assemblages shows important changes in a north–south direction. The fauna is predominantly subtropical–temperate off southern Angola, and tropical and more diverse in the central and northern parts, separated by the Angola–Benguela Front (Bianchi, 1992). Seabreams (Sparidae) and croakers (Sciaenidae) are prominent components of the fauna both in abundance and economic terms. In the southern shelf (south of Benguela), large-eyed dentex and African weakfish are the main species. Biomass estimates for both species have dropped substantially in recent years (INIP,2011). A decrease in seabream biomass (including several species of Dentex and Sparus) was also observed in the central region. However, the biomass estimates seem to be more stable in the region north of Ponta das Palmeirinhas (INIP, 2011). Reacting to this decline in major demersal fish species, Angola has reinforced the restrictions on bottom trawl fishing and reduced the number of licences and the TACs for these species. In South Africa, more than 200 species make up the landings from the line fishery (Verheye, 1998). Of these, 20 species can be considered economically important (Griffiths, 2000). However, South African landings of species such as seventy-four seabream (Polysteganus undulosus), red steenbras (Petrus rupestris), African weakfish (Atractoscion aequidens, known locally as geelbek) and others have fallen considerably since the 1960s when line-fish landings peaked. It is now considered that most of the major line-fish stocks are overexploited. The exceptions are probably snoek and yellowtail, which have been evaluated as being fully exploited (DAFF, 2011). The situation is similar in Namibia, where the authorities have decided to limit severely the capture of kob to give the stock a chance to recover (MFMR, 2010). South Africa has also introduced stringent regulations to recreational and coastal net fishing, aiming at recovering these important stocks (DAFF, 2011). In Namibia, the 2009 swept-area survey indicated an appreciable increase in total biomass of monkfish (Lophius vomerinus). Large-sized fish were also present in the population. These had not been seen during the surveys made in the previous three years. This suggests that there has been a partial recovery of the stock (MFMR, 2010). CrustaceansDeep-sea red crab, Namibia and Angola 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 indicates that it is currently overexploited, but probably recovering slowly (MFMR, 2010). The Angolan stocks of deep-water rose shrimp (Parapenaeus longirostris) and striped red shrimp (Aristeus varidens) are intensively exploited. This is despite a ban of foreign fishing that has been in place since 2004 after a period of marked decrease in abundances. Both stocks are considered to be fully exploited, although very intensively (INIP, 2011). Cape rock lobster, Southeast Atlantic The Cape rock lobster (Jasus lalandii) has been the subject of intense monitoring and assessment for almost a decade, following a sudden decline in somatic growth rates, hence, in productivity in the late 1980s. Current estimates are that the South African stock has undergone a major decline since landings peaked in the 1950s. The resource is currently estimated to be strongly overexploited (DAFF, 2011). As a result, a formal management procedure was implemented in 1997 to rebuild the stock to healthier levels, defined as pre-1990. After a major decrease in 2006 and a cut in TACs in the subsequent fishing seasons, stock abundance and growth seem to have started recovering in 2009. There are still concerns about increasing illegal fishing and this may jeopardize the recovery. In Namibia, the CPUE from the commercial fishery showed a modest growth in 2009 compared with 2008, as did the average size of the lobsters exported. However, recruitment seems to have been appreciably lower. Care is thus justified in the management of this stock (MFMR 2010). Southern spiny lobster, Southeast Atlantic The other important crustacean stock in Area 47 is the southern spiny lobster (Palinurus gilchristi). This is estimated to have declined continuously between the 1988–89 season and 1998–99. Since then, the stock seems to have recovered, probably helped by a reinforcement of management measures introduced in 2000 and 2001. These measures included a reduction in the number of vessels active in the fishery by 30 percent. The species is now considered to be fully exploited (DAFF, 2011). MolluscsCape Hope squid, Southeast Atlantic The major mollusc fisheries in Area 47 are those for Cape Hope squid, locally known as chokka squid (Loligo vulgaris reynaudi) and abalone (Haliotis midae) in South Africa, and for cuttlefish (Sepia officinalis hierreda) in Angola. The abundance of the squid and cuttlefish tends to vary strongly depending on environmental conditions owing to their short life span. In contrast, the long-lived abalone shows less interannual variability in abundance. Recent assessments of the chokka squid have indicated that the stock is fully exploited. Current management is based on a cap on effort and closed seasons. These measures aim at restricting effort to a level that secures the largest landings in the long term, while maintaining the stock at a level that does not risk recruitment reduction (DAFF, 2011). There are no formal assessments of the cuttlefish stock exploited in Angola. The artisanal fishery is based on spawners and it is not showing signs of concern, thus leading to the conclusion that the stock is not overexploited. The prognosis for the stock of abalone in South Africa is pessimistic given the current scale of illegal harvests. 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. Sea urchins, Southeast Atlantic 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 exposed the young abalone to predation by the lobsters and other predators. This has negatively affected the reproductive success of the stock (Mayfield and Branch, 2000; Tarr and McKenzie, 2002). The fishery was closed between February 2008 and July 2010, but poaching is estimated to have continued. Poaching still continues at a high level, despite a reduction between 2002 and 2009. The most recent assessments (DAFF, 2011) indicate that, if poaching continues at the current level, the stock will continue to decrease. The assessments also indicate that spawner biomass could recover quickly, at least for the southern coast (where the lobster is not a problem), if poaching could be stopped. Deep-sea resourcesDeep-sea resources, Southeast Atlantic Deep-sea resources in the region have only been exploited commercially on a significant scale in Namibia. The country 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 landings of the early period in the development of the fishery would not be sustainable. Thus, 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 need to manage the deep-sea resources of the Southeast Atlantic in a rational and responsible manner, the coastal States of the region (Angola, Namibia, South Africa, and the United Kingdom of Great Britain and Northern Ireland [on behalf of Saint Helena and its dependencies Ascension and Tristan de Cunha]) took the initiative to begin negotiations for the establishment of an RFMO, the South East Atlantic Fisheries Organisation (SEAFO) in 1997. The organization was established within the framework of the 1995 UN Agreement on Straddling Fish Stocks and Highly Migratory Fish Stocks. The EU, 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 region managed by SEAFO includes a substantial portion of the high seas of the Southeast Atlantic (Area 47). It covers alfonsino, orange roughy, armourhead grenadier, wreckfish, deepwater hake and red crab. The agreement was signed on 20 April 2001 and came into force in 2003. As of 10 March 2011, the contracting parties to the SEAFO Convention are Angola, EU, Japan, the Republic of Korea, Namibia, Norway and South Africa. This organization is still in the early stages of development and some time will be needed before measures taken within its framework can be evaluated. Habitat Bio Climatic Zone: Tropical; Temperate; Polar. Water Area Overview Spatial Scale: Spatial Scale 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 Saint Helena, Ascension and Tristan da Cunha also fall within Area 47. Nominal landings 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 landings 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. This normally occurs between about 15°S and 17°S on the coastal shelf in southern Angola. North of the Angola-Benguela Front (ABF), most of the coastal shelf of Angola is dominated by the southward-flowing and less productive Angola Current. The Benguela ecosystem itself is subdivided into the northern Benguela system and the southern Benguela system. These are separated by the partial barrier of a very intense upwelling cell off the town of Lüderitz, some 300 km north of the border between Namibia and South Africa. Area 47 covers a total surface area of about 18.4 million km2, with less than 0.5 million km2 being shelf area. This part of the Southeast Atlantic is a very variable and dynamic region from the point of view of oceanography. This variability significantly influences the marine living resources (Hutchings et al., 2009). The last three decades have been characterized by several major oceanographic events that have influenced the dynamics of several important fish stocks. One of these is the occasional occurrence of low-oxygen water spreading across the bottom of the Namibia shelf (Bartholomae and Plas, 2007). A major such event occurred in the period 1993–94. In this period, low-oxygen water occupied most of the central and northern Namibian shelf, leading to the almost total loss of a cohort of juvenile hake (Woodhead et al., 1997, Hamukuaya, O’Toole and Woodhead, 1998). Low oxygen levels near the seabed have also affected the distribution of hake over the Namibian shelf in a number of years (Mas-Riera et al., 1990, Woodhead et al., 1998). The other major oceanographic event affecting the region is the “Benguela Niño” that recurs about once a decade. Benguela Niños are extreme warm events that can be seen as abnormally high and persistent sea surface temperatures (SSTs) along the coast of Angola and Namibia (Shannon et al., 1986). These anomalous warm events cause strong rainfall anomalies (Rouault et al., 2003) and drastically modify fish distribution and abundance (Boyer et al., 2001). Major Benguela Niños occurred in 1934, 1949, 1963, 1984 (Shannon et al., 1986) and in 1995 (Gammelsrød et al., 1998). The most recent Benguela Niño, in 1995, is credited with causing a 4–5° southward shift of the sardine population. It was also associated with high mortality and poor recruitment of several small pelagic fish species (Boyer and Hampton, 2001). The likely occurrence of a Benguela Niño in 2011 (IRI, 2011) will probably also create poor conditions for many fish stocks in the region (especially small pelagic fish). This will warrant more precautionary management measures to ensure the sustainability of the fisheries targeting them. In a related sequence of events, 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 B7.1 The Southeast Atlantic (Area 47) |
Water Area Overview | Water Area Overview Marine resources - Southeast Atlantic
fao Major | 47: Atlantic, Southeast |
| | | | Water Area Overview |
Water Area OverviewMarine resources - Southeast Atlantic Aq Res Struct Biological Stock: Biological Stock Exploit Profile of CatchesTotal nominal landings from the Southeast Atlantic (Area 47) increased from less than 0.5 million tonnes in 1950 to slightly more than 3 million tonnes in 1968 (Figure B7.2; Table D7). Landings varied at about 3 million tonnes until the end of the 1970s, before declining to fluctuate about 2.3 million tonnes in most of the following decade. They then decreased abruptly from 2.8 million tonnes in 1987 to 1.3 million tonnes in 1991. This was driven partly by a large decline in anchovy landings and policy changes in Namibia after it gained independence in 1990. Landings have remained under 2 million tonnes since then, with an average landing of about 1.6 million tonnes between 2000 and 2002 that declined to about 1.2 million tonnes in 2009. Landings from the region are dominated by ISSCAAP Group 35 (herring, sardine and anchovies), Group 37 (miscellaneous pelagic fishes [including horse mackerel]) and Group 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. In some cases, this fishing pressure led to quite severe declines in abundance that was reflected in declining landings. The position was stabilized in several of these cases by imposition of more rigorous management regimes. | Figure B7.2 Annual nominal catches by ISSCAAP species groups in the Southeast Atlantic (Area 47) |
The small pelagic fisheries of the region, which together account for the highest proportion of the landings by mass, are dominated by six taxonomic groups: Cape horse mackerel (Trachurus capensis) and Cunene horse mackerel (T. trecae), Southern African pilchard (Sardinops sagax, also still referred to as S. ocellatus), Southern African anchovy (Engraulis capensis), sardinellas (round Sardinella aurita and Madeiran or flat S. maderensis) and Whitehead’s round herring (Etrumeus whiteheadi). In 2009, Cape horse mackerel accounted for the largest landings 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 southern Angola, especially in the cold season. Cunene horse mackerel is the main exploited species off Angola, especially north of Namibe Province. Landings of the two horse mackerel species have declined since the late 1970s and mid-1980s. This was probably caused by the effects of heavy exploitation, particularly in Namibia and Angola, in this period. In both species, heavy exploitation in the late 1970s and 1980s was followed by a large reduction in fishing mortality when the then Soviet Union fleet was drastically reduced after 1989. The decrease in landings in this period also reflected this reduced effort. Effort has been increasing since the mid-1990s in most cases. Declared landings of Cape horse mackerel were 223 000 tonnes in 2008, the lowest since the mid-1970s, and increased slightly to 233 000 tonnes in 2009. Declared landings of Cunene horse mackerel have been fluctuating around 30 000 tonnes since 2003, with a very marked decline to 13 000 tonnes in 2009, partially as a consequence of stricter regulation in place in Angola. These landing values are very low in relation to typical landings of the 1970s and 1980s. Declared landings of Southern African pilchard increased steadily from a low of about 105 000 tonnes in 1996 to a peak of about 400 000 tonnes in 2004, to decrease again to about 110 000 tonnes in 2009. Declared landings of Southern African anchovy have increased steadily since falling to a minimum of 42 000 tonnes in 1996, fluctuating between 135 000 tonnes in 2006 and 289 000 tonnes in 2001, with a value of 266 000 tonnes in 2009 (Figure B7.4). Landings of Whitehead’s round herring fluctuated without a clear trend from the early 1980s, with a small peak in the mid-1990s and a maximum of 97 000 tonnes recorded in 1997. Since then, landings have been between 40 000 and 65 000 tonnes, apart from in 2000 and 2005 when they fell below 40 000 tonnes (Figure B7.4). The higher landings in 1995 (79 000 tonnes) and 1997 (97 000 tonnes) were probably, at least in part, a result of fishing effort being diverted to round herring from the struggling anchovy fishery, as the round herring is not regulated by a TAC in South Africa at present. North of the Benguela front, primarily in Angolan waters, sardinellas are the dominant clupeoid in landings. The two species tend to alternate in dominance. Between 1994 and 2004, the flat sardinella tended to dominate in surveys, but the situation has reversed since 2004. In 2009, most of the estimated sardinella biomass off Angola was composed of round sardinella (INIP, 2011). Landings of the two species combined peaked at 286 000 tonnes in 1977. After 1989, following a substantial reduction in fishing effort in the region, landings declined and were well under 100 000 tonnes in the 1990s (Figure B7.4). They increased to 114 000 tonnes in 2000 but fell again to under 30 000 tonnes in 2002, to recover slightly to 74 000 tonnes in 2009. | Figure B7.3 Annual nominal catches of selected species in ISSCAAP Group 37, Southeast Atlantic (Area 47) |
| Figure B7.4 Annual nominal catches of selected species in ISSCAAP Group 35, Southeast Atlantic (Area 47) |
The taxonomic groups most important in the demersal fisheries of the region include the shallow-water (Merluccius capensis) and deep-water (M. paradoxus) Cape hakes, devil anglerfish or Cape monkfish (Lophius vomerinus), snoek (Thyrsites atun), and also dentex, including Angolan (Dentex angolensis) and especially large-eyed dentex (D. macrophthalmus), which is important in Angola (Figures B7.5, B7.6 and B7.7). North of the Benguela front, primarily in Angolan waters, sardinellas are the dominant clupeoid in landings. The two species tend to alternate in dominance. Between 1994 and 2004, the flat sardinella tended to dominate in surveys, but the situation has reversed since 2004. In 2009, most of the estimated sardinella biomass off Angola was composed of round sardinella (INIP, 2011). Landings of the two species combined peaked at 286 000 tonnes in 1977. After 1989, following a substantial reduction in fishing effort in the region, landings declined and were well under 100 000 tonnes in the 1990s (Figure B7.4). They increased to 114 000 tonnes in 2000 but fell again to under 30 000 tonnes in 2002, to recover slightly to 74 000 tonnes in 2009. consistently above 10 000 tonnes from the early 1950s through to 1968, when they started to decline. They fell below 1 000 tonnes in 1980, and remained below this value until 1993. This marked the start of a recovery, leading to declared landings of more than 30 000 tonnes in 2009. Significant dentex landings are also recorded under the heading of large-eyed dentex, and these have ranged from 40 tonnes in 1994 to a maximum of 43 200 tonnes in 1976. Only 56 tonnes of large-eyed dentex landings were declared in 2009. | Figure B7.5 Annual nominal catches of selected species in ISSCAAP Group 32, Southeast Atlantic (Area 47) | | Figure B7.6 Annual nominal catches of selected species in ISSCAAP Group 34, Southeast Atlantic (Area 47) |
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 B7.7). The largest landings within this group, apart from dentex, are of West African croakers NEI (Pseudotolithus spp.), which are caught mainly by Angola. Declared landings of these fish fluctuated around 20 000 tonnes between 2002 and 2009. The period of increase in landings started in 1998, when they went from under 2 000 tonnes the previous year to more than 7 000 tonnes. Declared landings of mild (southern) meagre, known locally as kabeljou or kob (Argysomus inodorus, previously A. hololepidotus), are made mainly in Namibia and South Africa. Mild meagre landings have shown a sharp increase from an average about 1 200 tonnes before 2000 to an average of 22 000 tonnes in 2008–09. Declared landings of porgies and seabreams NEI (Sparidae) peaked at more than 61 000 tonnes in 1966 but soon dropped and have not been above 12 000 tonnes since 1970. Landings have been under 1 000 tonnes since 2000. The declared landings of southern meagre, dentex NEI and West African croakers NEI have increased very markedly in the last decade. The most recent landings are among the highest on record. The relatively high average landings of gobies are misleading. Apart from very high landings of 21 000 tonnes of gobies in 1998, landings of the group are generally well under 500 tonnes/year. From 2000 to 2009, the following groups generated annual landings that averaged more than 1 000 tonnes: sea catfishes NEI (Ariidae); panga seabream (Pterogymnus laniarius); groupers, seabasses NEI (Serranidae); threadfins, tasselfishes NEI (Polynemidae); bigeye grunt (Brachydeuterus auritus); croakers, drums NEI (Sciaenidae); pargo seabreams NEI (Pagrus spp.); sand (locally “white”) steenbras (Lithognathus mormyrus); grunts, sweetlips NEI (Haemulidae); and Canary drum (Baardman, Umbrina canariensis). Declared landings of picarels NEI (Spicara spp.), geelbek croaker (Atractoscion aequidens), carpenter seabream (Argyrozona argyrozona), black seabream (Spondyliosoma cantharus), porgies, seabreams NEI (Sparidae), mullets NEI (Mugilidae) and white stumpnose (Rhabdosargus globiceps) ranged between 100 and 500 tonnes/year in the same period. Sharks, rays and chimaeras (ISSCAAP Group 38) did not use to account for substantial declared landings in Area 47. However, their landings have increased rapidly in recent years. Annual declared landings of the group have averaged 17 500 tonnes since 2000. These are made up primarily of: blue shark (Prionace glauca); unidentified sharks, rays, skates, etc.; unidentified raja rays; shortfin mako (Isurus oxyrinchus); and Cape elephantfish (Callorhincus capensis); their landings peaked in 2007 at a total of some 28 600 tonnes. Landings then declined to about 15 800 tonnes in 2009. In recent years, there has been substantial interest in exploitation of the deep-sea species of the Southeast Atlantic (Area 47), including orange roughy (Hoplostethus atlanticus), alfonsino (Beryx splendens) and Patagonian toothfish (Dissostichus eleginoides). Landings of Patagonian toothfish have been taken in the EEZ of South Africa at the Prince Edwards Islands (Commission for the Conservation of Antarctic Marine Living Resources [CCAMLR] Subareas 58.6 and 58.7). Therefore, they fall outside the geographic area of this review. Almost all of the deepwater fishing in the Southeast Atlantic has been undertaken in Namibian waters. Landings of alfonsino peaked at more than 4 000 tonnes in 1997 but declined thereafter. The average yearly landings in the 2000s reached only 360 tonnes, with just over 300 tonnes declared in 2009. Declared landings of orange roughy reached a peak of more than 18 000 tonnes in 1997, but declined steadily after that to 380 tonnes in 2005. The declared landings for 2008 and 2009 did not reach 10 tonnes. | Figure B7.7 Annual nominal catches of selected species in ISSCAAP Group 33, Southeast Atlantic (FAO Area 47) |
Several crustacean species support valuable fisheries in Area 47 (Figure B7.8). Geryon crabs, dominated by the red crab (Chaceon maritae), are taken in both Namibian and Angolan waters. Recorded landings of Geryon crabs peaked at more than 10 000 tonnes in 1993 but fell in the following years, with average yearly landings in 2000–08 of about 3 800 tonnes. The highest declared landings of crustaceans were of shrimps, particularly the deep-water rose shrimp (Parapenaeus longirostris) and the striped red shrimp (Aristeus varidens). Declared landings of deep-water rose shrimp were more than 5 600 tonnes in 2001, the highest figure since the start of the 1990s. However, the landings declined to 1 400 tonnes in 2005 and to 160 tonnes in 2009, probably as a result of stringent management measures imposed on the fishery. The same pattern was observed with landings of the striped red shrimp, which reached 3 400 tonnes in 2001, the highest recorded since 1987. Landings declined to just over 360 tonnes in 2005 and 250 tonnes in 2009, after major fluctuations (reaching 1 200 tonnes in 2007). The Cape rock lobster (Jasus lalandii) and southern spiny lobster (Palinurus gilchristi) occur towards the south of the region, with the Cape rock lobster occurring on the west coast of Namibia and South Africa, and the southern spiny lobster off the south coast of South Africa. Annual landings of Cape rock lobster have levelled off under TAC management at about 2 500 tonnes after a steady decline since the peak of more than 25 000 tonnes per year in the 1950s. Landings in 2009 were just over 2 100 tonnes. Landings of southern spiny lobster, also managed by a TAC, were reasonably constant between about 800 tonnes and 1 100 tonnes in the 1990s. They declined and became more variable after 1999, with an average of 540 tonnes in the 2000s and about 370 tonnes in 2009. The island of Saint Helena also occurs in Area 47, and it has recorded landings of Tristan da Cunha rock lobster (Jasus tristani) that have been quite stable, varying between 300 and 500 tonnes, since 1980. The highest landings of more than 800 tonnes were reported for 1972 and 1976. | Figure B7.8 Annual nominal catches of selected species ISSCAAP Groups 42, 43 and 45, Southeast Atlantic (Area 47) |
The major fisheries for molluscs in the region are those for Cape Hope squid, also known as chokka squid (Loligo vulgaris reynaudii), and perlemoen abalone (Haliotis midae). The highest landings of squid were made in 1989 (10 730 tonnes) and, since then, landings have shown considerable variability, as would be expected from a short-lived species. Landings have varied from a peak of more than 7 500 tonnes in 1996 to a low of 2 800 tonnes in 1992 (Figure B7.9). Landings in 2009 were 10 100 tonnes. Landings of abalone have declined fairly steadily since a peak of more than 4 000 tonnes in the mid-1960s. They were maintained between about 550 and 750 tonnes from the mid-1980s to the very early 2000s, before dropping further to reach only 60 tonnes in 2008. The introduction of a total ban on the fishery in February 2008 meant that no more landings were declared in 2009. The fishery was re-opened in July 2010 with a TAC of 150 tonnes. | Figure B7.9 Annual nominal catches of selected species ISSCAAP Groups 52 and 57, Southeast Atlantic (Area 47) |
Management Management: Management In more recent years, more conservative management measures have generally been put in place. At present, the most important resources are managed either for sustainable yields or with a goal of encouraging recovery. The three countries in the region have well-developed management systems in place for the fisheries exploiting their most important stocks. Of the three countries, fisheries management is least developed in Angola. However, it is still improving and further developing its fisheries management system for the most important resources. Nevertheless, in common with most fisheries in the world, substantial problems still exist in many fisheries. There are varying underlying causes that include environmental variability, scientific uncertainty and conflicting biological and socio-economic objectives. Difficulties in MCS occur throughout the region. These are particularly significant in some coastal fisheries where access and landings are difficult to control. A documented example of this is the severe problems with illegal fishing that are being experienced in the South African 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 2006, more than 1 million abalone individuals were confiscated by the law enforcement agency. It is estimated that the illegal catch of abalone exceeded the legal commercial catch by more than tenfold in the past decade, with a total level that currently exceeds 1 000 tonnes/year (DAFF, 2011). In addition, more than two-thirds of the illegally caught abalone that were confiscated were below the minimum legal size. The status of the abalone stock was considered too low to allow commercial exploitation in 2008. A ban on commercial abalone fishing was imposed in February 2008, with a re-opening in July 2010. In addition, recreational fishing of abalone has been forbidden since the 2003–04 fishing season. Sources Marine and Inland Fisheries Service, Fisheries and Aquaculture Resources Use and Conservation Division. FAO Fisheries and Aquaculture Department “Review of the state of world marine fishery resources” FAO FISHERIES AND AQUACULTURE TECHNICAL PAPER. No. 569. Rome, FAO. 2011.
http://www.fao.org/docrep/015/i2389e/i2389e.pdf Bibliography The bibliographic references are available through the hyperlink displayed in "Source of Information". ACKNOWLEDGEMENTS The authors would like to thank Filomena Vaz-Velho and Kumbi Kilongo N’Singi, from the National Institute of Fisheries Research, (INIP) of Angola, Graça d’Almeida, from the National Marine Information and Research Centre (NatMIRC) of Namibia, and Johan Augustyn, Justice Matshili and Deon Durholtz, from the Department of Agriculture, Forestry and Fisheries (DAFF), South Africa for their valuable comments and inputs. Special thanks also to all the colleagues from INIP, NATMIRC and DAFF, who along the years have maintained high-quality fisheries research programmes providing the information this review is based on, because without their work there would still be no scientific knowledge on the status of exploited fish stocks in this region. |
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