Marine resources - Southwest Atlantic, 2005|
| Marine Resource Fact Sheet |
| | | | Marine resources - Southwest Atlantic, 2005 |
| |  |
| | Owned by | Food and Agriculture Organization (FAO)
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| | | Main Descriptors | Considered a single stock: No
Spatial Scale: Regional
Considered a management unit: No |
| Considered a single stock: A group of individuals in a species occupying a well defined spatial range independent of other stocks of the same species. It can be affected by random dispersal movements and directed migrations due to seasonal or reproductive activity. |
| Spatial Scale: Spatial scale contains a standard term such as Global, Regional (e.g. for the whole Atlantic), sub-regional (e.g. for a part of the Atlantic), national, local (for sub-national levels). |
| 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. |
| | | | | | Habitat and Biology Climatic zone: Tropical ; Temperate ; Polar Water Area Overview This Area covers a total surface of
17.65 million km2 off the eastern South
American coast, between latitudes
05o00’N off northern Brazil and
60o00’S off southern Argentina and
includes a total shelf area of 1.96
million km2 (Figure B6.1). In the north,
in the Amazon River area the
continental shelf may extend as far as
160 nm (320 km) offshore where the
bottom is mostly river deposits and
debris. As one moves south away from
the influence of the Amazon River the
shelf becomes narrow, coraline and
mostly unsuitable for trawling. The
shelf is also narrow and mostly rocky further
south, off central and southern Brazil, becoming
wider and more suitable for trawling only as
higher latitudes are approached. The best and
largest trawling areas are found in the River Plate
area and over the Patagonian shelf and the
Falkland-Malvinas area, where the shelf extends
well beyond the 200 nm limit (more than
370 km) off the coastline, turning this into the
largest shelf area in the southern hemisphere.
The variety and abundance of fishery resources
and types of fisheries in this area are determined
by the topography and other physical
characteristics, including the environmental
conditions that range from typically tropical in
the north to sub-Antarctic in the south. Towards
the northern part of this area, the marine
environmental conditions are dominated by the
South Equatorial Current that flows from the
coast of Africa and encounters the South
American coast branching into the North Brazil
Current that flows along the north Brazilian coast and the Brazil Current that flows south, along the
central and southern Brazilian coast. The
northern part of the area is further influenced by
the great flow of fresh water from the Amazon
River. Further south, the marine environment is
dominated by the warmer south-flowing Brazil
Current and then by the colder northern-flowing
Falkland-Malvinas current, which merge into an
offshore flow of subtropical convergence just off
the River Plate area where there is also a great
flow of freshwater in to the coastal areas
(Emílsson, 1959; Hempel, 1971; Dias Neto and
Mesquita, 1988; Bakun and Parrish, 1991;
Bakun, 1993; Castro and Miranda, 1998).
Shrimps and lobsters, and to a lesser extent reef
fishes and other tropical demersals tend to be of
particular relevance towards the northern part of
the area. Further south, in nutrient-rich coastal
areas where water masses mix off central Brazil
and off Uruguay-northern Argentina, the area
sustains important populations of small pelagics,
particularly in the River Plate area. Coastal
demersals are particularly important off southern
Brazil and in the River Plate area, while mid- and
deepwater demersals tend to dominate over most
of the River Plate, the Patagonian and Falklands-
Malvinas shelf area, where there is also an
important squid fishery. Large pelagics are
mostly caught off central Brazil and the River
Plate area.
 | Figure B6.1 The Southwest Atlantic (Area 41)
 |
Geo References  | | Distribution of Marine resources - Southwest Atlantic
| FAO major areas | 41: Atlantic, Southwest |
| | | | | | Intersecting Major FAO areas and LME areas |
The following area codes have been found as intersecting the distribution of Marine resources - Southwest Atlantic | FAO major areas | 41:
Atlantic, Southwest | | (LME) Large Marine Ecosystem Areas | 13: Humboldt Current | | 14: Patagonian Shelf | | 15: South Brazil Shelf | | 16: East Brazil Shelf | | 17: North Brazil Shelf |
Resource Structure Considered a single stock: No Exploitation Profile of catches
Total capture fish production from the southwest
Atlantic area comes mostly from demersals, and
more recently from squids mainly caught in the
southern Patagonian shelf and slope area. This is
one of the FAO Statistical Areas were capture
fisheries have seen a rapid development in terms
of total production, with a more or less sustained
rate of increase until recent years. In 1950 the
total catch for the whole area was only 172 000t,
and by then most of the known fish stocks in the
area were only lightly or moderately exploited
with several important stocks still virtually
unexploited. Several new fisheries have
developed since and except for the burst in
catches between 1966 and 1968, with a peak
catch of 599 000t in 1967 caused by an intense
pulse fishing of hake and probably other
demersals by the ex-USSR fleet, total annual
catches increased almost steadily at an average
rate of 7.4 percent per year, to reach a maximum of 2.4 million tonnes in 1987. This was followed
by a decline, with some year-to-year fluctuations,
to a low 2.0 million tonnes in 1990 and
2.1 million tonnes in 1994. A new maximum was
reached in 1997 at 2.8 million tonnes. Catches
have declined since, with approximately 2.0 million t landed in 2002 (Figure B6.2 and Table D6). Worth mentioning is that total marine
aquaculture production has increased in this area
at a rate of almost 42 percent per year over the
last five years, from 8 000t in 1996 to 72 000t in
2002, but contributing only 3 percent of the total
production in this area.
Demersal species in ISSCAAP Group 32 (cods,
hakes, etc.) and molluscs in Group 57 (squids,
etc.), are the major contributors to the catches
from this area, followed by the coastal species in
Group 33 (croakers, weak fishes, etc.), the small
pelagics in Group 35 (herrings, sardines,
anchovies, etc.), and other demersals in Group 34
(toothfish, cusk-eel, etc.) and Group 38 (sharks,
rays, chimaeras, etc.). The dominant species in
terms of volume are the Argentine hake
( Merluccius hubsii), the Patagonian grenadier
( Macruronus magellanicus), and the southern
blue whiting ( Micromesistius australis) in the
demersals Group 32, the Argentine shortfin squid
( Illex argentinus) in Group 57, and the Brazilian
sardinella ( Sardinella brasiliensis) in the small
pelagics Group 35.
The Argentine hake sustains one of the most
important fisheries in the River Plate area and
over most of the Patagonian shelf. From 1950
total catches of this species, at first all taken by
the coastal states, Argentina, Brazil and Uruguay,
increased steadily to 102 000t in 1965. Following
the exceptionally high catches of hake reported
by the USSR in 1966 (56 000t), 1967 (513 000t)
and 1968 (100 000t), catches by the same coastal
states and then total catch for the area declined to
70 000t in 1969 to then increase steadily to
462 000t in 1979. Total catch of hake declined to
a low 255 000t in 1984, and increased again to a
record high of 682 000t in 1996. Since then, total
catches of this species have steadily declined to a
record low in the last 25 years of 243 000t in
2000, with an increase to slightly over 400 000t
in 2002 (Figure B6.3).
 | | Figure B6.2 Annual nominal catches ('000t) by ISSCAAP species groups in the Southwest Atlantic (Area 41)
|
The Argentine hake is now mostly exploited by
Argentine and Uruguayan fleets. Both fleets
increased in the 1980s to the early 1990s, and the
fleet of Argentina continued to increase in the 1990s. Other deepwater demersals in the Group
32 which make a significant contribution to the
total fish production in the area are the
Patagonian grenadier and the southern blue
whiting (Figure B6.3) that produced 116 000t and
64 000t respectively in 2002. These are
particularly abundant in the southern Patagonian
shelf and slope area, where they are exploited by
long-range fleets from the region as well as from
distant areas.  | | Figure B6.3 Annual nominal catches ('000t) of selected species in ISSCAAP Group 32, Southwest Atlantic (Area 41)
|
The miscellaneous demersals in Group 34
(Figure B6.4) that mostly contribute to the total
fish production in this area are the pink cusk eel
( Genypterus blacodes) and Patagonian toothfish
( Dissostichus eleginoides) with 20 000t and
11 000t respectively in 2002. These species are
exploited by both coastal and long-range fleets
from the region and from other areas. Coastal
demersal species within Group 33 also produce
significant catches within the area, particularly
the Argentine croaker ( Umbrina canosai), the
stripped weak fish ( Cynoscium striatus), the
whitemouth croaker ( Micropogonias furnieri),
and the weakfishes ( Cynoscion spp.), which have
reported relatively high and stable catches over
the past few years, with a total of 113 000t for the
four species group and 247 000t for the whole
species group in 2002. These species are all
exploited by coastal fleets.  | | Figure B6.4 Annual nominal catches ('000t) of selected species in ISSCAAP Group 33 and 34, Southwest Atlantic (Area 41)
|
The main small pelagic species within Group 35
are the Brazilian sardinella ( S. brasiliensis) and
the Argentine anchovy ( Engraulis anchoita).
After the record catches of 228 000t of Brazilian
sardinella reported in 1973, total catches of this
species have been declining, although with some
marked year-to-year fluctuations, to hit a lowest
level of 17 000t in the year 2000, with a slight
increase to 35 000t in 2001 and catches of
28 000t in 2002 (Figure B6.5). Catches of
Argentine anchovy have been between 10 000t
and 25 000t per year in recent years. Catches of
tunas and other large pelagics in Group 36 have
been more or less stable at 50 000-60 000t per
year, after reaching a maximum of 74 000t in
1996.  | | Figure B6.5 Annual nominal catches ('000t) of selected species in ISSCAAP Groups 35, 36, Southwest Atlantic (Area 41)
|
Another very important fishery in this area is that
for squids (Group 57). The main dominant
species is the Argentine shortfin squid ( Illex
argentinus) which represents 94 percent of the
squid catches and 24 percent of total marine
catches in this area in 2002. The overall
abundance and actual catches of Argentine shortfin squid have been very variable since the
fisheries started in the late 1970s. After reaching
638 000t in 1993, total catches of this species
declined to 506 000t in 1994, to increase again to
a record high of 1.1 million tonnes in 1999 and
decline to 930 000t in 2000 and to a further
511 000t in 2002 (Figure B6.6). Although less abundant, total catches of Patagonian squid
( Loligo gahi) have also been fluctuating between
a maximum of 89 000t reached in 1989 and a low
22 000t in 1997. In 2002, the total catch of this
species was 25 000t. Other squid species caught
occasionally are the sevenstar flying squid
( Martialia hyadesi), that except for a record high
catch of 24 000t in 1995, followed by 3 800t and
8 300t in 1996 and 1997, respectively, had
relatively low catches in other years, ranging
from 0 and 1 000t per year. Catches of nonidentified
squids has declined sharply in recent
years, suggesting great improvements in the
identification at species level of squid catches
from the area.  | | Figure B6.6 Annual nominal catches ('000t) of selected species in ISSCAAP Group 57, Southwest Atlantic (Area 41)
|
Shrimps, prawns, lobsters, crabs and other
crustaceans in Groups 42, 43 and 45, also sustain
important local fisheries in the area, from the
tropical to the sub-Antarctic zone. Altogether
these species groups have yielded total catches of
over 100 000t since 2000 (Figure B6.7) which are
important volumes considering their relatively high market value. The single crustacean species
yielding the highest catches is the Argentine red
shrimp ( Pleoticus muelleri), with highly variable
catches ranging from 3 000 to almost 40 000t per
year since the fishery started in the 1980s, with
record high catches of 79 000t reported in 2001.
Around 8 percent of the total catches in this area
(176 000t in 2002) are reported as not identified
marine fishes in the official FAO statistics
grouped under ISSCAAP Group 39 (marine
fishes not identified). These mostly come from
small-scale fisheries, particularly in Brazil, where
the variety of species and landing sites makes the
recording of catches by species a rather difficult
task.  | | Figure B6.7 Annual nominal catches ('000t) of selected species in ISSCAAP Groups 42, 43 & 45, Southwest Atlantic (Area 41)
|
Management Considered a management unit: No International fisheries research, stock assessment and fisheries management activities in the area are mostly dealt through bilateral arrangements. The Joint Technical Commission for the River Plate Maritime Front, based in Montevideo, Uruguay, was established in 1973. One of of its main objectives is the promotion of bilateral cooperation between neighbouring Argentina and Uruguay regarding the assessment and management of shared stocks in the River Plate Maritime Front (“Frente Marítimo del Río de la Plata”, http://www.cofremar.org), taking management action when required. In so doing, this Commission has been organizing or coordinating joint research surveys and other research activities in the area under its competence. It has also actively promoted scientific meetings and publications of regional and international relevance, where various stock assessment and fisheries management issues of interest to the two member countries but also to other countries in Latin America and countries fishing in the area are or were addressed and discussed. While very active in the 1980s and 1990s, the activities of this regional Commission have decreased somehow, particularly with regards to their scientific activities having a wider regional or international coverage.
Argentina and the United Kingdom are also cooperating in the assessment of fish stocks and management of fisheries in the Falklands- Malvinas area. In November 1990 the Governments of Argentina and the United Kingdom signed a joint statement on the conservation of fisheries that established a South Atlantic Fisheries Commission, composed of delegations from both States (http://www. oceanlaw.net./docs/ficz4.htm, last visited 26/10/03). The South Atlantic Fisheries Commission meets regularly and provides a forum for the exchange of information on marine living resources and the discussion and implementation of measures to improve the conservation of commercially important fish stocks and the management of fisheries exploiting them in the southwest Atlantic with particular reference to the Falklands-Malvinas area.
Brazil has some ten informal permanent working groups (Grupos Permanentes do Estudos, GPE), which over the years have had variable degrees of activity and in certain circumstances have been instrumental in coordinating research work and in providing technical advice on the assessment and management of important fisheries in Brazil, such as tunas, shrimps, lobsters, sardines and coastal demersals. Through some of these working groups covering the northernmost part of Area 41, there is an active cooperation with the Western Central Atlantic Fisheries Commission (WECAFC) covering Area 31 regarding the study and assessment of fish stocks in the Guyana-Brazil area. Most of these fisheries are under some kind of management scheme with specific management measures varying from one country to another and from one fishery to another. Enforcement, however, is not always as effective as desirable. Only a few fisheries are under an open access regime and these are mostly coastal small-scale fisheries. In most cases there is a limited access scheme for which a fishing licence is required, which is usually combined with other nominal fishing effort and total catch limitations to keep fishing mortality under control. Also size at first capture regulations and seasonal and area closures are used to protect juveniles and spawners. In particular, Argentina and Uruguay and their sub-regional organization, the Frente Marítimo, have been compelled to adopt more severe restrictive regulations, combining TAC limits, size at first capture limits and seasonal and area closures to face the critical situation of the Argentine hake stock. Biological State and Trend History Until the late 1970s and early 1980s, this area
was amongst the few major fishing areas of the
world still having a large potential for expansion
and where abundant and potentially valuable fish
resources were still reported as underexploited or
lightly exploited (FAO, 1979, 1981, 1983; Otero
et al., 1982, 1983; Csirke, 1987; Dias Neto and
Mesquita, 1988). Several coastal and mostly
industrialized long-range fisheries have
developed since and most of the fish stocks are
now considered to be fully exploited, while some
are, or have been, overexploited, even severely,
in recent years (Bezzi, Akselman and Boschi,
2000; Dias Neto, Saccardo and Bernardino, 2001;
FAO, 1997, 2002). Most of the reported expansion in production in
Area 41 over the last two decades is due to the
increased catches of hake and more recently of
other demersals as well as squids, particularly in
the Patagonian shelf and slope area. There are
two well known species of hake in this area, the
Argentine hake ( Merluccius hubsii) and the Patagonian or southern hake ( M. australis) and a
third one ( M. patagonicus, sp. nov, Lloris and
Matalallanas, 2003), has recently been described. Argentine hake But by far the Argentine hake is the most
conspicuous and abundant, while its area of
distribution and fishing grounds tend to overlap
in the outer Patagonian shelf and slope with that
of the southern hake and the new described one,
from which it can hardly be distinguished from
simple observation. Given the higher abundance
and relative importance of the Argentine hake, it
is likely that at least some proportion of the
actual catches of southern hake are reported as
Argentine hake. Reported catches of southern
hake have been well under the 10 000t per year in
recent years, while those of Argentine hake have
been in the range of 243 000 to 682 000t per
year.
There seem to be at least two stock units of
Argentine hake ( M. hubbsi), with some authors
proposing the existence of three-four and up to
five stock units (Otero and Kawai, 1981; Bezzi
and Perrotta, 1983; Otero, Giangiobbe and Renzi,
1986; Perrotta and Sanchez, 1992; Bezzi,
Verazay and Dato, 1995). However, this possible
distinction into two or more stock units are not
taken into account in the official annual catch
statistics and are not always taken into account in
the assessment and management of the hake
fishery within the common Argentine-Uruguayan
fishing zone and in the remaining Patagonian
shelf area.
The assessments available indicate that until the
1980s and early 1990s the stocks of Argentine
hake were fully exploited, but this soon
developed into a state of overexploitation by the
mid-1990s and stock depletion later on (FAO,
1983; Csirke, 1987; Bezzi, Verazay and Dato,
1995; Consejo Federal Pesquero, 1998; Aubone
et al., 1998; Bezzi, Aubone and Irusta, 1999;
Aubone, 2000; Bezzi, 2000; Bezzi, Akselman
and Boschi, 2000; INIDEP, 2001; Tringali and
Bezzi, 2001; Arena and Rey, 2003). At first the
overexploitation of the hake stocks was mainly
caused by growth overfishing, soon evolving into
recruitment overfishing with a serious depletion
of the spawning stock biomass. This resulted in
the hake resource to be declared in a state of
emergency and called for severe restrictive
measures by both main fishing countries,
Argentina and Uruguay, since 1998. The
restrictive measures are still in force and include
reduced Total Allowable Catch quotas (TACs) and extensive seasonal and zonal closures to
protect juveniles and spawners. While some signs
of increased recruitment are being reported, the
restrictive measures adopted so far do not seem
to have caused the drastic reduction in fishing
pressure which would have allowed a more rapid
long-lasting recovery of the Argentine hake
stocks in the area.
Southern hake In comparison to the Argentine hake, the
southern hake ( M. australis) stock is much
smaller and is distributed further south in the
southern region of the Patagonian shelf and slope
with possible connection with a larger stock of
the same species in Area 87, off the southern
coast of Chile (Tingley et al., 1995). The stock of
southern hake is considered to be fully exploited
and current catches are within the recommended
TAC for this species. However, as suggested by
Bezzi and Dato (1995), the situation could easily
deteriorate if only a small fraction of the large
fleet fishing for Argentine hake switches its effort
to southern hake. Patagonian grenadier and Southern blue whiting The Patagonian grenadier ( Macruronus
magellanicus) is usually found in deeper waters
in the southern Patagonian Shelf and according to
recent estimates is considered to be moderately
exploited, with current catches being well under
the estimated TACs. The other main fish stock in
Group 32 is the southern blue whiting
( Micromesistius australis), that is also found in
deeper waters in the southern Patagonian Shelf
and slope, particularly around the Falkland
Islands (Malvinas). While this stock was
considered to be moderately to fully exploited
until the mid-1990s, more recent studies suggest
that at current catches the stock of southern blue
whiting is being overexploited (Bezzi, Akselman
and Boschi, 2000; Cordo and Wöhler 2000;
Wöhler, 2000; Consejo Federal Pesquero, 2002). Other demersal fish stocks in group 34 Other demersal fish stocks in Group 34, such as
the Patagonian toothfish ( Dissostichus
eleginoides) and the pink cusk eel ( Genypterus
blacodes) are considered as moderately to most
likely fully exploited in this area, although there
is the general perception that at least the
Patagonian toothfish is in a much critical
situation due to high non reported catches in
international waters. Other stocks of coastal demersal species in group 33 There are several stocks of
coastal demersal species of Group 33 throughout
the region. The main species in this ISSCAAP
Group are the Atlantic croaker ( Umbrina
canosai), stripped whitefish ( C. striatus), various species of weakfishes ( Cynoscium spp.) and the
whitemouth croaker ( Micropogonias furnieri).
Most of these stocks are fully exploited, while
some local stocks are still being moderately
exploited and others are giving clear signs of
overexploitation (Otero and Ibañez, 1986;
Haimovici, 1988; Arena, 1990; Dias Neto and
Dornelles, 1996; Arena and Rey, 1999; Bezzi,
2000; Bezzi, Akselman and Boschi, 2000). Brazilian sardinella off Central Brazil The Brazilian sardinella ( Sardinella brasiliensis)
is one of the main small pelagics in ISSCAAP
Group 35 being exploited in this area. It is found
over the shallower continental shelf off Central
Brazil between 22º and 29ºS. After the record
high catches of 228 000t obtained in 1973,
catches of this species dropped to then fluctuate
in the range of 100 000t and 250 000t until 1986,
when another period of decline occurred. The
total biomass of Brazilian sardinella declined
from an estimated 350 000t in 1977 to 80 000t in
1997, and since then there have been no signs of
stock recovery (Saccardo and Rossi-
Wongtschowski, 1991; Rossi-Wongtschowski,
Saccardo and Cergole, 1995, 1996; Matsuura,
1998; Vasconcellos, 2001). The causes of the
severe decline and lack of recovery of this
sardine stock is a source of great interest and
active debate among fisheries scientists and
administrators (Saccardo 1983; Saccardo and
Rossi-Wongtschowski, 1991; Rossi-
Wongtschowski, Saccardo and Cergole, 1996;
Dias Neto, Saccardo and Bernardino, 2001;
Vasconcellos, 2003). All seems to indicate that as
with other stocks of sardines in other parts of the
world, the Brazilian sardine is also exposed to
decadal cycles of favourable and unfavourable
environmental conditions that could drive the
population size up and down more or less
independently of fishing pressure. This comes in
addition to the effects of heavy fishing, which
seems to have maintained this sardine stock
under a state of overexploitation almost
continuously since its first recorded outburst
more than three decades ago. In this respect, it
has already been suggested that excessive fishing
pressure could contribute to making declining
biomass abundance trends steeper and delay or
compromize possible natural increasing trends. Argentine anchovy, Southwest Atlantic Another small pelagic fish stock particularly
abundant in the Southwest Atlantic is the
Argentine anchovy ( Engraulis anchoita) that
usually is found off southern Brazil, Uruguay and
northern Argentina, although in some years it has been reported as far north as Central Brazil, in
areas usually inhabited by Brazilian sardine
(Lima and Castello, 1994). This is one of the few
cases of highly abundant, well-known
commercial fish stocks of the world that still
remains underexploited. Total catches are in the
lower tens of thousands tonnes per year, while
the potential for the whole distribution area is
more in the order of one or more hundred
thousand tonnes. The total estimated biomass of
Argentine anchovy, while highly variable, has
mostly been well over one million tonnes, with
maximum estimates close to 10 million tonnes in
some years (Ciechomski and Sánchez, 1988;
Hansen and Madirolas, 1999). This is a stock that
clearly could support a much higher fishing
pressure. However, it is clear that, as the species
is close to the base of the food web of the
northern Patagonian and River Plate system, any
significant increase in the fishing pressure on this
stock could have negative impacts on other fish
stocks feeding on it. Tuna and other large pelagics Catches of tunas and other large pelagics have
been more or less stable in recent years and most
stocks seem to be fully exploited although some
room for limited expansion exists in some cases.
Total catches of sharks, rays and chimaeras have
remained more or less stable or increased slightly
over the last decade or so, with 57 000t reported
for this species group in 2002. Although some
stocks are not subject to direct fishing, they
might still be moderately or fully exploited as bycatch
in other more intensive demersal fisheries
in the area. Due to their low fecundity and other
life history characteristic there is some concern
that through this indirect fishing individual
populations of sharks, rays and chimaeras be
exposed to undesirably high fishing mortality,
become overexploited and in extreme cases
depleted, even if not targeted by any particular
direct fishery. More studies are needed in this
respect, particularly in the context of the IPOA
on sharks. Crustaceans Amongst the crustaceans, the most abundant
single species producing the highest yield is the
Argentine red shrimp ( Pleoticus muelieri) in the
central Patagonian Shelf area (Boschi, 1989;
Bezzi, Akselman and Boschi, 2000). This stock is
considered to be fully exploited. Argentine shortfin squid Another main stock is the Argentine shortfin
squid (Illex argentinus), which is distributed
along the shelf and slope from 22º to 54ºS and is exploited by long range fleets from the area as
well as from distant areas. Several studies have
been conducted on the shortfin squid stock in the
Patagonian Shelf and slope area (Koronkiewicz,
1980, 1986; Brunetti, 1981; Otero et al., 1982;
Hatanaka, 1986, 1988; Csirke, 1987; Haimovici
and Perez, 1990; Haimovici et al., 1998; Bakun
and Csirke, 1998). Some work has been done to
distinguish possible population groups or stocks
units in the area by analysing differences in
reproductive seasonality and distribution of early
and older life stages. At least three main
spawning stocks are described, the summerspawning
stock, the south Patagonic stock and a
Bonaerensis-north Patagonic stock, with a
possible fourth one, the southern Brazil stock,
that could well be an extension of the
Bonaerensis-north Patagonic stock.
During the first years of rapid development of
this fishery there was great uncertainty and
concern regarding the state of this stock and the
risk of overexploitation. However, the various
research and management efforts made and in
particular the joint or coordinated actions by
Argentina and the United Kingdom in the context
of the South Atlantic Fisheries Commission have
contributed to improve the assessment,
monitoring and control of fishing operations of
local and particularly of long-range fleets.
Regardless of the high year to year variability in
abundance and resulting catches, the Argentine
shortfin squid as well as the Patagonian squid are
considered fully exploited. Source of information FAO Marine Resources Service, Fishery Resources Division. “Review of the state of world marine fishery resources” FAO Fisheries Technical Paper. No. 457. Rome, FAO. 2005. 235p.
 . Bibliography The bibliographic references are available through the hyperlink displayed in "Source of Information". |
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