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INTERNATIONAL COMMISSION FOR THE CONSERVATION OF ATLANTIC TUNAS (ICCAT) – 1
INVENTORY OF NATIONAL AND REGIONAL APPROACHES TO FISHERIES REBUILDING PROGRAMMES © OECD 2012
INTERNATIONAL COMMISSION FOR
THE CONSERVATION OF ATLANTIC TUNAS (ICCAT)
Description of national level detailed assessment of the state of fish stocks
The International Commission for the Conservation of Atlantic Tunas (ICCAT) is
responsible for the study of the populations of tuna and tuna-like fishes and other species
of fishes, primarily Yellowfin tuna, Bigeye tuna, Skipjack, Albacore, Atlantic Bluefin,
Southern Bluefin (which falls under the ICCAT mandate for the Atlantic but is managed
by CCSBT), Mediterranean Swordfish, sailfish, blue and white marlin, Spanish and king
mackerel, small tunas such as black Skipjack, frigate tuna, and Atlantic bonito, and
pelagic sharks exploited in tuna fishing in the Convention area that are not currently
under the jurisdiction of other international fishery organizations. ICCAT conducts
studies which include research on the abundance, biometry and ecology of the fishes, the
oceanography of their environment, and the effects of natural and human factors upon
their abundance. ICCAT maintains the ability to utilize the technical and scientific
services of, and information from, official agencies of the Contracting Parties and their
political sub-divisions and may utilize the available services and information of any
public or private institution, organization or individual, and may undertake, within the
limits of its budget, independent research to supplement the research work being done by
governments, national institutions or other international organizations.
ICCAT‟s goal is to maintain the populations of tuna and tuna like species “at levels
which will permit the maximum sustainable catch for food and other purposes” as stated
in the Preamble to the ICCAT Convention.
The status of some of the target species governed by ICCAT can be found in a recent
report.1
Yellowfin tuna
Yellowfin tuna is distributed mainly in the tropical and subtropical oceanic
waters of the Atlantic, Pacific and Indian oceans. Juveniles form mixed schools
with skipjack and juvenile bigeye, mostly in surface waters, while larger fish
form schools in surface and sub-surface waters.
Spawning occurs in the equatorial zone of the Gulf of Guinea, in the Gulf of
Mexico, in the southeastern Caribbean Sea, and off Cape Verde, but the relative
importance of these spawning grounds is unknown. Although such separate
spawning areas might imply separate stocks or substantial heterogeneity in the
distribution of yellowfin tuna, a single stock for the entire Atlantic is assumed as
1 www.iccat.int/Documents/Meetings/Docs/2010_SCRS_ENG.pdf
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INVENTORY OF NATIONAL AND REGIONAL APPROACHES TO FISHERIES REBUILDING PROGRAMMES © OECD 2012
a working hypothesis, based in part on a 40-year time series of longline catch
data that indicates yellowfin are distributed continuously throughout the entire
tropical Atlantic Ocean.
The most recent full assessment was conducted in 2003 applying various age-
structured and production modelsto the available catch data through 2001. These
analyses implied that although the 2001 catches were slightly higher than MSY,
effective effort may have been either slightly below or above (up to 46%) that
necessary to achieve MSY, depending on the assumptions. Catches have been in
decline since the last assessment, they are lower than MSY and some surface
fishing effort has transferred to other oceans. Catches have declined by more
than half from close to 200 000 tonnes in 1990 to 97 800 tonnes in 2006 partly
due to a reduction in eastern Atlantic purse seine effort, but other factors have
caused the reduction of baitboat and purse seine catches in the western Atlantic,
as well as the more recent declines of longline catches in both the western and
eastern Atlantic. It may be difficult to assess whether catch declines are due to
stock declines, to reduced effort or other factors. In 1993, the Commission
recommended that there be no increase in effective fishing effort exerted on
Atlantic yellowfin tuna, over that observed in 1992. As measured by fishing
mortality estimates from the 2003 assessment, effective effort in 2001 appeared
to be approaching or exceeding that of 1992. Catches have been declining since
2001, as has the nominal effort of the purse seiners, but the trend in effective
effort is not clear.
Yellowfin tuna appear to have been harvested in the vicinity of MSY in the late
1990s and the early 2000s, but catches and effort have declined since. It is not
known if the productivity of the resource has decreased, implying that MSY
would now be lower, or if the fish have become less available. It would be
prudent to assume that the productivity has in fact declined until it can be
demonstrated that this is not the case.
Bigeye tuna
MSY estimate not available. Although in 1990 Bigeye tuna stocks declined rapidly,
stocks have been stabilized recently. However, there is a lack of information regarding
detailed fishing and size data from certain fleets, in addition to past catch and fishing
activities of IUU fleets. If major countries were to take their entire catch limits and other
countries were to maintain their recent catch levels, total catch would then exceed
100,000 tons, well above the total catch of 85 000 tonnes that the Committee
recommends for rebuilding efforts. There is no rebuilding plan in place.
Bigeye tuna are distributed throughout the Atlantic Ocean between 50ºN and 45ºS,
but not in the Mediterranean Sea. Spawning takes place in tropical waters when the
environment is favourable. From nursery areas in tropical waters, juvenile fish tend to
diffuse into temperate waters as they grow larger. Catch information from surface gears
indicate that the Gulf of Guinea is a major nursery ground. Available evidence suggests
an Atlantic-wide single stock.
Bigeye tuna is exploited mostly by longline, baitboat and purse seine used by many
countries throughout its range of distribution. The total annual catch increased relatively
steadily to more than 132,000 tonnes in 1994 before decreasing for all major gears to
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76,000 tonnes in 2006. Decreased catches are due to reductions in fleet size for purse
seine and longline and lower CPUE for longline and baitboat.
The 2007 stock assessment examined production models, VPA, and a statistical
integrated model. Information is still lacking on size data from certain fleets, including
IUU fleets which makes it necessary to assume catch-at size for an important part of the
overall catch. The results from non-equilibrium production models are considered to best
characterize the status of the resource. Current MSY is estimated to be approximately
90 000 tonnes, reflecting the existing mix of fisheries that capture small or large bigeye.
MSY estimates can change considerably with changes in the relative fishing effort
exerted by surface and longline fisheries. The biomass at the beginning of 2006 was
estimated to be nearly 92% of BMSY and the 2005 fishing mortality rate was estimated to
be about 13% below FMSY.
Skipjack tuna
MSY estimate not available . The increased use of fish aggregation devices (FADS)
and the increase of the fishing area towards the west since the early 1990s have led to an
increase in Skipjack catchability and the proportion of Skipjack stock that is exploited.
Estimates of catches made in 2007 indicate a 10% increase from the average of 2002-06.
Traditional stock assessment is difficult to apply to Skipjack tuna because of their
particular biological and fishery characteristics; several assessment methods were used to
assess stocks and several fishery indicators were analyzed; separate assessments were
made for eastern and western stocks. There is no rebuildling plan in place.
Skipjack tuna is the predominant species under fish aggregating devices (FADs)
where it is caught in association with juvenile yellowfin tuna, bigeye tuna and with other
species of epipelagic fauna. It spawns from its first year of life opportunistically
throughout the year and in vast sectors of the oceans. Skipjack tuna is considered resilient
to exploitation. Total catches increased steadily from less than 10 000 tonnes in the early
1960s to more than 200 000 tonnes in 1991. Catches have since declined to about 150 000
tonnes in 2006.
Numerous changes in the skipjack fishery since the early 1990s (such as the use of
FADs and the expansion of the fishing area towards the west) have caused an increase in
skipjack catchability and in the proportion of the skipjack stock that is exploited.
according to a tag-recovery model on fish measuring 40-60 cm FL. Estimates of Z based
on the annual average size of the catches suggests a smaller increase and even a decrease
after 1995.
Atlantic skipjack have not been assessed since 1999 although there are some signs of
local overexploitation. No standardized assessment of the Atlantic skipjack stocks can be
carried out, but the development of several fishery indicators are believed to reflect the
changes in the state of the stock over time. Although the fisheries operating in the east are
extending towards the west beyond 30oW longitude, the hypothesis of two distinct stock
units continues to be used. However, given the biological characteristics of the species
and the geographic distances between the various fishing areas, using smaller stock units
could be investigated.
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Albacore tuna
In northern stocks of Albacore, which are exploited by surface fisheries targeting
immature and sub-adult fish, longline fisheries target immature and adult Albacore.
Recent catch rates have showed declines; decreases in longline fisheries are mostly due
to decrease in landings by Chinese Tai Pei fleet and a decrease of Albacore as by-catch
by the Japanese. Based on the 2007 assessment which considers catch, size and effort
since the 1930s, the spawning stock biomass (SSB) has declined and is currently about
one quarter of the peak estimated for the late 1940s.
TAC for northern Albacore stock was 34, 500 tons until 2007, and the Committee noted
that reported catches for 2005 and 2006 were over TAC. Stock projections indicate that
the northern stock will not recover from overfished conditions if catch levels remain over
30 000 tonnes. Recent catches for southern stocks have been below TAC level. Although
assessments show that stocks are overfished currently, model projections indicate that
should catch levels remain at the 2006 level, stocks will recover to MSY levels. There is
no rebuilding plan in place.
Estimates of recruitment to the fishery, although variable, have generally been higher in
the 1960s and earlier periods with a declining trend thereafter. The most recent
recruitment is estimated to be large but it is uncertain. The stock appears to have rebuilt
to near BMSY. Recent fishing mortality rates have generally been above FMSY (current F is
approximately 50% larger than FMSY). Yearly estimates of MSY varied depending on the
relative combination of fisheries taking juvenile and mature albacore.
The South Atlantic albacore fishery has been dominated by the surface baitboat fleets
from South Africa and Namibia, and the longline fleets from Brazil and Chinese Taipei.
The surface fleets direct for albacore and mainly catch juvenile and sub-adult fish (70-90
cm FL). Total reported albacore landings for have fluctuated between 25 000 tonnes and
40,000 tonnes for the last 20 years without clear trend. In the South Atlantic, based on
the 2007 assessment which considers catch, size and effort since the 1950s, the Southern
albacore spawning stock has declined to about 25% of the unfished SSB. It is likely that
the stock is currently below MSY while the 2005 fishing mortality rate was about 60%
of FMSY. MSY was estimated to be around 33 300 tonnes.
There are insufficient data to assess albacore in the Mediterranean; it is recommended
that that more information be collected for Mediterranean albacore so that an assessment
be conducted at the earliest possible date.
In 2007, a TAC reduction was advised for the North Atlantic stock and no change for the
South Atlantic stock. SSB is estimated to be smaller than the SSB at MSY for both the
northern and the southern stock. Fishing mortality is estimated to be above FMSY in the
northern stock but less than FMSY in the southern stock.
Atlantic Bluefin tuna
With regard to Atlantic Bluefin a lack of compliance with the TAC and
underreporting of catches by fishing vessels undermine efforts to conserve stock. Exports
to Japanese and US markets greatly exceed the reported catches. Poor temporal and
spatial coverage coupled with substantial underreporting of total catches hinder efforts to
accurately assess the state of stocks. The committee‟s results from the most recent
assessment made in 2006 indicate that spawning stock biomass has been declining rapidly
in the last several years, while fishing mortality has been increasing rapidly. Fishing
mortality is most likely 3 times that which would result in MSY and biomass 36% less
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than the level needed to support MSY. Substantial overfishing is occurring and spawning
biomass is well below the levels needed to sustain MSY. There is no rebuilding plan in
place.
ICCAT has two management units for bluefin tuna, the West Atlantic and the East
Atlantic plus Mediterranean. Recent stock assessments have been conducted under a two
stock hypothesis, but the 2008 assessment also considered a preliminary single stock
hypothesis assessment for exploratory purposes.
Catches now come from considerably smaller area than in the 1960s, including the
disappearance of fisheries off Brazil and off Norway; catches in the West are now much
smaller than in the 1960s; fisheries have expanded in the middle of the Atlantic north to
Iceland; and purse seine catches have been eliminated in the West but have increased
considerably in the Mediterranean, particularly in the eastern Mediterranean where there
were few catches in the 1960s.
Since the imposition of TACs in 1981, the total catch for the West Atlantic including
discards has stabilized between about 2 100 tonnes and 3 300 tonnes. The SCRS was
particularly concerned that the TAC has been seriously under caught in recent years. In
the East Atlantic, reported catches increased from the early 1980s to the late 1990s and
have been generally declining since. In the Mediterranean, reported catches were
generally less than 10 000 tonnes from 1950 to 1980, increased steeply to 40 000 tonnes
in the mid 1990s, decreased abruptly from 1996 to 1999 and have generally remained
above 20 000 tonnes since.
The introduction of farming activities into the Mediterranean in 1997 and good
market conditions resulted in rapid increases in fishing effort in the Mediterranean
fisheries for bluefin tuna. Reported catches in recent years are believed to be considerably
smaller than actual catches. For the West Atlantic, the 2006 assessment suggests that SSB
declined rapidly in the early 1970s followed by a more gradual decline with the 2004 SSB
being about 19% of the 1975 SSB. While it is clear that current biomasses are
considerably smaller than those of the early 1970s, year classes since the mid 1970s have
not been large enough to rebuild the stock. If small year classes since the mid-1970s are
due to low spawning stock, then rebuilding the SSB should lead to progressively larger
year classes and it would be possible to rebuild the stock. For the eastern Atlantic and
Mediterranean, the 2006 assessment suggested that the biomass declined by
approximately half from the early 1970s to the mid-1980s, subsequently increased until
the early 1990s and has been decreasing since to the lowest observed in the time series
(Figure BFT 5). Fishing mortality, particularly on older and larger bluefin, is estimated to
have increased sharply and be about 3 times FMSY. This increase in fishing mortality
estimated for large bluefin is consistent with a shift in targeting towards larger individuals
destined for fattening/farming. The SCRS believes that the TAC regulation have been
largely ineffective in controlling overall catch with actual catches believed to be 18 000
tonnes to 20 000 tonnes higher than reported. It also believes that the 15-year recovery
plan for East Atlantic and Mediterranean bluefin is a step in the right direction, but that it
is unlikely to rebuild to BMSY in 15 years with 50% probability.classes are due to causes
other than low spawning stock, e.g. changed environmental conditions, loss of spawning
habitats, or losses of spawning components, then, it may not be possible to rebuild the
stock to the high biomasses estimated for the 1970s and earlier unless catches are reduced
to near zero.
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INVENTORY OF NATIONAL AND REGIONAL APPROACHES TO FISHERIES REBUILDING PROGRAMMES © OECD 2012
Southern Bluefin Tuna
There has been no assessment of Southern Bluefin stock by ICCAT; a separate
assessment was done by Commission for the Conservation of Southern Bluefin Tuna
(CCSBT).
Atlantic Swordfish
According to the last assessment made in 2006, Atlantic Swordfish stocks were in good
condition, on track to achieving MSY. However, higher catches of southern stocks as
currently envisioned by the Commission may not be sustainable, from targeted and by-
catch indicators.
Swordfish are distributed widely in the Atlantic Ocean and Mediterranean Sea. There are
three management units: Mediterranean group, North Atlantic, and South Atlantic
separated at 5°N. Mixing is expected to occur and be highest at the boundary in the
tropical zone. The last Atlantic swordfish assessment was conducted in 2006.
Swordfish spawn in the warm tropical and subtropical waters throughout the year,
although seasonality has been reported in some areas. They are found in the colder
temperate waters during summer and fall. Because of the broad geographic distribution
of the Atlantic swordfish in coastal and off-shore areas, mostly ranging from 50ºN to
45ºS, the species is available to a large number of fishing countries. The ages exploited
in the North Atlantic fisheries include primarily ages two and three in recent years. The
largest proportion of the Atlantic catches is made using surface drifting longline.
However, many additional gears are used, including traditional gillnets off the coast of
western Africa.
In the North Atlantic estimated catch averaged about 11 600 tonnes over the last 10
years. In the South Atlantic, catches were generally less than 5 000 tonnes (with an
average value of 2 300 tonnes) prior to 1980. After 1980, landings increased
continuously up to a peak of 21 780 tonnes in 1995, similar to the peak of North Atlantic
harvest, due in part to progressive shifts of fishing effort to the South Atlantic.
Expansion of fishing activities by southern coastal countries also contributed to this
increase in catches. The reduction in catch following the peak in 1995 resulted from
regulations and is due in part to a shift to other oceans and target species.
The 2006 assessment indicated that North Atlantic swordfish biomass had improved
possibly due to strong recruitment in the late 1990s, combined with reductions in
reported catch since then, especially compared to the peak catch values of 1987. The
estimate MSY is about 14 100 tonnes. The biomass at the beginning of 2006 was
estimated to be about 99% of SSBMSY and the 2005 fishing mortality rate was
estimated to be about 14% below FMSY.
The 2006 assessment for South Atlantic swordfish uses a composite CPUE pattern that
has been constructed from directed and by-catch fisheries, which indicates that F is
likely below FMSY, and that current SSB is likely above SSBMSY. The 2006
assessment suggested that the Recommendation 2006-02 on catch limits, if fully
realized, would lead the northern stock to likely decline to below BMSY. For the
southern stock, the 2006 assessment results suggest that biomass is above BMSY and F
less than FMSY, but it was unclear whether substantially higher catches than currently
envisioned by the Commission could be sustained in the long term.
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In 2007, the SCRS recommended that the existing TAC (14 000 tonnes), which is close
to the estimated MSY (14 100 tonnes), should allow the northern Atlantic swordfish to
continue to grow towards BMSY. For the South Atlantic, the SCRS recommended that
annual catch should not exceed the provisionally estimated MSY (about 17 000 tonnes).
Mediterranean Swordfish
Gradually declining stock biomass of Mediterranean Swordfish has fallen below the
level which can support MSY, and fishing mortality has exceeded levels which could
support MSY.
Mediterranean swordfish is considered to be separate from the Atlantic stocks.
Mixing is believed to be low and generally limited to the region around the Straits of
Gibraltar. The most recent assessment was conducted in 2007, making use of catch and
effort information through 2005.
Reported catches have fluctuated without trend between 12,000-16,000 tonnes over
the last 10 years. Catches are of the same magnitude as those in the north Atlantic,
although the area is much smaller. This could be due to higher productivity or lower
predation in the Mediterranean. The sharp increase between 1983 and 1988 may be
partially attributed to improvement in the national systems for collecting catch statistics.
The main fishing gears are surface longline and gillnets, but harpoon, trap and
recreational fisheries also report swordfish catches. Following ICCAT recommendations
for a general ban of driftnets in the Mediterranean, the gillnet fleet has been decreasing,
although the total number of vessels cannot be determined from ICCAT statistics.
Production modelling using a long time series of data suggests that the biomass is
slightly below BMSY and that F is some 25% above FMSY, while VPA using a shorter
time series of data suggest that biomass is less than half BMSY. Based on the VPA
results, there is a non-negligible risk that current F could cause rapid declines in the stock.
Sailfish
Sailfish has a pan-tropical distribution. There are two management units, eastern
Atlantic and western Atlantic. The last ICCAT sailfish assessment was conducted
in 2001.
Sailfish are targeted by coastal artisanal and recreational fleets but they are also
caught as by-catch by longliners and purse seiners (Figure SAI 1). Catches of
sailfish were reported together with spearfish by many longline fleets and, in the
statistics, it is not possible to separate the catches of these two species or to
distinguish sailfish caches from catches reported as unclassified billfish The 2001
assessments of these two stocks were not considered reliable but there were
indications of early decreases in biomass. It is not known if either of the sailfish
stocks is fished above FMSY or if the biomass is less than BMSY. There is no
basis to provide indications as to the future evolution of catches or of the stocks.
The status of the stocks is unknown with respect to exploitation or biomass. It
would be prudent to stabilize or reduce fishing mortality, but the paucity of
information makes it difficult to quantify any reduction that may be required.
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Small tunas
There has been no assessment of small tunas, as there have been problems with
data collection.
Blue and White Marlin
Biomass levels for Blue and White Marlin remain below levels needed to achieve
MSY. Between 2001 and 2005 several abundance indicators suggested that the
decline in biomass had at least partially halted; other indicators suggest
abundance has continued to decline.
Biomass levels for White Marlin also remain below levels necessary to achieve
MSY, and fishing mortality at a higher rate than that which is necessary to
achieve MSY. Combined longline indices and some individual fleet indices
suggest the decline has been partially reversed; other indices suggest it has
continued to decline. The current management plan has the potential to recover
the stocks of blue and white marlin; however, recent increases in catch of Blue
Marlin by artisanal fisheries in both sides of the Atlantic may negate the
effectiveness of ICCAT‟s recovery plans.
Catches of blue marlin and white marlin continued to decline through 2004.
Based on the 2006 assessment, the decline in abundance of blue marlin may have
slowed or halted, and white marlin may have increased slightly. Recent biomass
for blue marlin likely remains well below the BMSY estimated in 2000, F has
recently declined and is possibly smaller than Freplacement (which would allow
the stock toincrease) but larger than FMSY estimated in the 2000 assessment.
Recent biomass for white marlin most likely remains well below the BMSY
estimated in the 2002 assessment, F is probably smaller than Freplacement and
probably also larger than the FMSY estimated in the 2002 assessment.
Blue Shark
Biomass for the Blue Shark is believed to be above the amount necessary to support
MSY and current harvest levels below the fishing mortality level needed to achieve MSY;
however, results are highly uncertain. The biomass of the shortfin mako shark could be
below the biomass level that would support MSY, and has been deemed a „non-negligible
issue‟. There has been no assessment done as of yet on the porbeagle shark, although a
recent study done by Canadian scientists showed that porbeagle stocks have been
depleted to levels well below the biomass level needed to support MSY, by as early as
2004. Recent fish monitoring information suggests that harvest rates have exceeded
sustainable levels and led to further decline in the stock. Rebuilding to MSY levels could
require long recovery periods due to the level of depletion and the low intrinsic rate of
increase of the stock. Most Atlantic pelagic sharks have very limited biological
productivity; a species can be overfished even at very low levels of fishing mortality.
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Legislative and policy framework
Legislation specific to fisheries rebuilding, as well as complementary legislation
ICCAT is comprised of contracting parties; any government that is a member of the
United Nations (UN), any specialized UN agency, or any intergovernmental economic
integration organization constituted by States that have transferred to it competence over
matters governed by the ICCAT may join the Commission. Contracting parties of ICCAT
include the United States, Japan, South Africa, Ghana, Canada, France (in respect of St.
Pierre and Miquelon), Brazil, Morocco, Korea, Cote d‟Ivoire, Angola, Russia, Gabon,
Cape Verde, Uruguay, Sao Tome e Principe, Venezuela, Republic of Equatorial Guinea,
Republic of Guinea, United Kingdom (on behalf of its Overseas Territories), Libya,
People‟s Republic of China, Croatia, European Union, Tunisia, Panama, Trinidad &
Tobago, Namibia, Barbados, Honduras, Algeria, Mexico, Vanuatu, Iceland, Turkey,
Philippines, Norway, Nicaragua, Guatemala, Senegal, Belize, Syria, St. Vincent and the
Grenadines, Nigeria, Egypt, Albania, Sierra Leone, Mauritania. Co-operators include
Chinese Taipei, Guyana, and the Netherland Antilles. There is also the status of a
Cooperating Non-Contracting Party and Fishing Entity.
The SCRS is composed of the Species Groups, working groups that assess the status
of the various stocks, and two Sub-Committees: Statistics and Ecosystems. Four Panels
are responsible for keeping under review the species, group of species, or geographic area
under its purview: Panel 1: Tropical Tunas (Yellowfin, Skipjack and Bigeye); Panel 2:
Northern Temperate Tunas (Albacore and bluefin); Panel 3: Southern Temperate Tunas
(Albacore and Southern Bluefin); and, Panel 4: Other species (Swordfish, billfishes,
sharks). The Panels review scientific and other information and make recommendations
for joint action by the Contracting Parties aimed at maintaining the stocks at levels that
will permit maximum sustainable catches. The Panels may also recommend to the
Commission studies and investigations necessary for obtaining information relating to its
species, group of species, or geographic area, as well as the co-ordination of research
programs by the Contracting Parties.
Key terminology and definitions
Age of Recruitment: The age when fish are considered to be recruited to the fishery. In
stock assessments, this is usually the youngest age group considered in the analyses,
typically age 0 or 1.
Allocation: The partitioning of fishery controls or fishing rights among participating
entities or operating units. For example, the allocation of the TAC into country-specific
quotas.
Availability: Refers to the distribution of fish of different ages or sizes relative to the
distribution of the fishery.
Biological Reference Point (BRP): A benchmark against which the abundance of the
stock or the fishing mortality rate can be measured in order to determine its status.
These reference points can be Limits or Targets, depending on their intended usage.
(Caddy and Mahon 1995; Gabriel and Mace 1999; Sissenwine and Shepherd 1987)
Biomass: Biomass refers to the abundance of the stock in units of weight. Sometimes,
“biomass” refers to only one part of the stock (spawning biomass, exploitable biomass)
but this distinction is not always made.
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Biomass at MSY: A biological reference point. It is the long-term average biomass value
expected if fishing at FMSY. The text of the International Convention for the
Conservation of Atlantic Tunas states that ICCAT is responsible for “studying and
appraising information concerning measures and methods to ensure maintenance of the
populations of tuna and tuna-like fishes in the Convention area at levels which will
permit the maximum sustainable catch and which will ensure the effective exploitation
of these fishes in a manner consistent with this catch” (Article IV, paragraph 2.b).
(Caddy and Mahon 1995)
By-catch: Catch of species other than the intended target species in a fishing operation.
Bycatch can either be discarded or landed. (Alverson et al. 1994)
Carrying Capacity: (1) Virgin biomass. (2) Refers to the holding capacity of a fishing
vessel.
Catch (C): The total number of fish caught by fishing operations (sometimes “catch” is
used to denote the weight of fish caught). Catch should pertain to all fish killed by the
act of fishing, not just those fish that are landed. Catches are reported to ICCAT as part
of the “Task I” data.
Catchability (q): The fraction of the stock which is caught by a standardized (effective)
unit of effort. It is also used as the constant of proportionality that relates effective effort
to fishing mortality (q x f = F) or as the constant of proportionality that relates an index
of abundance to absolute stock size (I = q x N). Catchability is affected by fish
availability. Thus, specific climatic conditions may result increased or decreased
availability of the fish. This would lead to increased (decreased) catchability and, thus,
increased (decreased) fishing mortality rate with the same fishing effort.
Commercial: Refers to catch or effort that is commercial in nature, typically using
industrial-type vessels and gears.
Confidence Limits: A statistical measure of uncertainty, providing the
lower and upper bounds within which a parameter falls with a given probability.
Example: the 80% confidence limits for SSB are the low and high values within which
SSB lies with 80% certainty.
Controls: Refers to the various controls (measures) that managers can impose to
regulate fishing. Controls are usually classified as effort controls or catch controls,
depending on what they intend to regulate. (Gulland 1974; Pallarés and Suzuki 1998)
Conversion Factors: Multipliers applied to convert landings into Nominal Catches.
These factors vary with the species involved and with the dressing of the fish (e.g. fresh,
frozen, gutted, etc.,.). They could also vary by country and over time.
Discards: Refers to part of the catch that is thrown overboard at sea. Discards may be
released either dead or alive. Scientists generally estimate the dead discards as part of
the total catch. Estimates of discards can be made in a variety of ways, including
samples from observers and logbook records. Fish (or parts of fish) can be discarded for
a variety of reasons such as having physical damage, being a non-target species for the
trip, and compliance with management regulations like minimum size limits or quotas.
EEZ: Exclusive Economic Zone (defined in the Law of the Sea Convention).
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Effective Effort (f): Measures of fishing effort such as hooks per day of fishing that have
been standardized so that the measure is proportional to the fishing mortality rate that
the
gear(s) impose on the stock of fish. Controls purported to limit effective effort imply
that the fishing mortality rate is to be limited.
Effort (Fishing Effort, f): A measure of the intensity of fishing operations. How Effort is
defined depends on the type of fishery (gear) and often on the type of information
available. For longline fisheries, effort is usually defined in units of number of hooks or
in hook-hours. For purse-seine fisheries, effort is often defined as boat-days (time
fishing plus search time). Scientists should aim to define effort in a way that facilitates
effort standardization.
Equilibrium: A situation that arises when the fishing mortality, exploitation pattern and
other fishery or stock characteristics (growth, natural mortality, recruitment) do not
change from year to year. Many yield per recruit analyses assume equilibrium. That is,
equilibrium yield per recruit that is computed for a given fishing mortality can be
achieved if that fishing mortality is held constant for many years (as many years as there
are age classes in the fishery); equilibrium yield per recruit values computed for a new
level of fishing mortality or a change in selectivity would not be expected to reach
equilibrium until several years from the time of implementation (see Transitional).
Other types of stock assessments such as variants of stock production models or catch
curves also assume equilibrium. Their non-equilibrium variants aim to better explain the
dynamics of the observed data through time. (Hilborn and Walters 1992)
Equilibrium Yield Curve: A function that describes the long-term yield which would be
obtained at different levels of fishing mortality. At its highest point, the equilibrium
yield is the Maximum Sustainable Yield (MSY) and the associated fishing mortality rate
is FMSY. (Restrepo et al. 1994)
Excess Capacity: In the short-term, it is the fishing capacity over and above that which
is needed to extract the TAC from the stock. In the long-term, it is the fishing capacity
over and above that which is needed to achieve the management objectives (e.g. to
generate a fishing mortality equal to FMSY).
Exploitable Biomass: Refers to that portion of a stock´s biomass that is available to the
fishing gear.
Exploitation Pattern: The distribution of fishing mortality over the age composition of
the fish, determined by the type of fishing gear and spatial and seasonal distribution of
fishing, and by the growth and migration of the fish. In other words, it is the combined
effect of gear selectivity and fish availability. The pattern can be changed by
modifications to fishing gear; for example, by increasing mesh or hook size or by
changing the ratio of harvest by gears exploiting the fish (e.g., gill net, trawl, hook and
line). The pattern can also change due to changes in fishing practices such as avoidance
of areas where juveniles reside.
Exploitation Rate: The proportion of a population at the beginning of a given time
period that is caught during that time period (usually expressed on a yearly basis). For
example, if 220,000 fish were caught during the year from a population of 1 million fish
alive at the beginning of the year, the annual exploitation rate would be 0.22.
Exploitation Ratio: The ratio of fish caught to total mortality (= F/Z).
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F 0.1: A biological reference point. It is the fishing mortality rate at which the increase
in equilibrium yield per recruit in weight for an increase in a unit of effort is 10% of the
yield per recruit produced by the first unit of effort on the unexploited stock (i.e., the
slope of the yield per recruit curve for the F0.1 rate is only 1/10th of the slope of the
yield per recruit curve at its origin). [Note: F0.1 is sometimes computed from
equilibrium yield curves]. Originally, F0.1 was intended as an economic reference
point, measuring where additional investment into effective fishing effort would only
produce a 10% marginal gain in yield per recruit. It later evolved into a conservative
reference point for yield optimization because F0.1 results in almost as much yield per
recruit as Fmax does, but at lower levels of fishing mortality. (Caddy and Mahon 1995)
Fmax: A biological reference point. It is the fishing mortality rate that maximizes
equilibrium yield per recruit. Fmax is the F level that defines growth overfishing. In
general, Fmax is different than FMSY (the F that maximizes sustainable yield), and is
usually higher than FMSY, depending on the stock-recruitment relationship. By
definition, Fmax is always higher than F0.1. (Caddy and Mahon 1995)
FAD (Fish Aggregating Device): Artificial or natural objects placed on the surface that
attract several species underneath, thus increasing their catchability. (Kwei and
Bannerman 1993; Pallarés et al. 1998)
Fecundity: The number of eggs produced on average by a female of a given size/age.
Fecundity information is often used to compute spawning potential.
Fishing Capacity: Usually refers to the size and characteristics of individual fishing
vessels (see Carrying Capacity).
Fishing Gears: The equipment used for fishing. Some of the most common fishing
gears for tunas and tuna-like fish are baitboat, gillnet, handline, harpoon, troll, haul
seine, longline, widwater trawl, purse seine, rod-and-reel, trap, and trawler (see gear
codes towards the end of the Glossary). Each of these can have multiple configurations.
Fishing Mortality Rate (F): The part of the total mortality rate that is due to fishing.
Fishing mortality is usually expressed as an instantaneous rate, as discussed under
Mortality Rate, and can range from 0 per year (for no fishing) to high values such as 1.0
or more per year. Fishing mortality should reflect all deaths in the stock that are due to
fishing, not just those fish that are actually landed. It is common practice to refer to F as
a scalar value but it would be more appropriate to refer to it as a vector. That is, it is
important to consider how F is distributed among age groups (i.e. what the exploitation
pattern is). For instance, and F value of 0.5 for a stock exploited by purse seines that
target small fish would have very different consequences than an F=0.5 for the same
stock exploited by longlines targeting large fish.
Fishing Pattern: See Exploitation Pattern. Sometimes the term is also used in reference
to the way in which fishing operations are conducted.
Flag of Convenience (FOC): The term pertains to cases when a boat is registered in a
different State than that of ownership, for whatever reasons of convenience.
Growth Rate: (1) Intrinsic growth rate: A value that quantifies how much a population
can grow between successive time periods. The intrinsic growth rate is often estimated
with production models and plays an important role in evaluating the sustainability of
different harvest levels. (2) Individual growth rate: A value that quantifies how fast the
average individual in the population grows in size or in weight.
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Landings: The part of the catch that is landed.
Limit Reference Point: A benchmark that should not be exceeded with any significant
probability according to a given set of management objectives. According to the UNIA,
FMSY should be a limit reference point. ICCAT´s objectives do not define limit
reference points explicitly, although FMSY is the implied target. (Caddy and Mahon
1995)
Minimum Size: A control available to managers, intended to minimize the catches of
small fish. Such a control is often decided upon based on yield per recruit
considerations like avoiding growth overfishing. That is, minimum size regulations aim
to alter the exploitation pattern so that young fish are given a better chance to grow
before being vulnerable to fishing.
Model: A conceptual and simplified idea of how the “real world” works.
Mortality Rate (instantaneous): Conceptually, the easiest way to describe mortality is
as a fraction (e.g. 0.3 or 30% of the fish die in a year). Because fishing and natural
mortality happen continuously throughout the year, it is not straightforward to use these
fractions in an additive way. Expressing these processes as instantaneous rates (i.e. as
the fractions that die in infinitesimal periods of time) facilitates the stock assessment
analysis computations on an annual basis, even when the catches take place daily.
Instantaneous mortality rates of 0.1, 0.5 and 1.0 are equivalent to 10%, 39% and 63%
mortality.
Natural Mortality Rate (M): The part of the total mortality rate that is due to causes
other than fishing (e.g., predation, disease, cannibalism, and perhaps increasingly,
environmental degradation such as pollution). These many causes of death are usually
lumped together for convenience, because they are difficult to separate quantitatively.
Sometimes natural mortality is confounded with losses of fish from the stock due to
emigration. M has proven very difficult to estimate, and values are often assumed based
on life history characteristics such as longevity. Also, M values are often assumed to
remain constant through time and by age.
Nominal: Refers to quantities as they are reported, before any analyses or
transformations. Nominal catch is the sum of catches that have been reported as round
weight or, equivalently, the landings (nominal catches do not include such measures as
unreported dead discards). Nominal effort pertains to measures of fishing effort or
vessel carrying capacity that have not been standardized. When catchability changes,
e.g., through changes in gear technology, trends in nominal effort can give a misleading
picture of trends in exploitation.
Observer: An independent person that collects information onboard fishing vessels.
Observer programs can be used for quantifying bycatch and dead discards, collecting
tag returns, etc. (Matsumoto and Miyabe 1999)
Overfished: Overfished means that the abundance of the stock is “too low”. In many
fisheries fora the term is used when biomass has been estimated to be below a limit
biological reference point that is used as the signpost that defines an “overfished
condition”. ICCAT has not formally defined when a stock is to be categorized as being
overfished, so usage of the term may not always be consistent. (Mace 1998)
Overfishing: The term generally means that the fishing mortality being exerted on the
stock is “too high”. In many fisheries fora the term is used when F has been estimated to
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be above a limit biological reference point that is used as the signpost that defines
“overfishing”. Usage of the term is not limited to “growth overfishing” situations; it can
also pertain to recruitment overfishing and to other types of overfishing. As with the
term Overfished, ICCAT usage of “overfishing” may not always be consistent. (Mace
1998)
Parameter: A quantity that characterizes a population variable in a statistical sense. In
population dynamics models, parameters such as the rates of growth, mortality and
reproduction provide the essential characteristics of the population.
Pelagic: A species that lives in midwater or close to the surface. Tunas and tuna-like
fishes are generally referred to as “large pelagics”.
Population: A group of fish of one species which shares common ecological and genetic
features. The stocks defined for the purposes of stock assessment and management do
not necessarily coincide with self-contained populations.
Population Dynamics: In general, refers to the study of fish stock abundance and why it
changes over time.
Population Model: A component of a stock assessment model, made up of formulations
that describe how the population changes from one time period to the next. The types of
population models used by ICCAT vary, depending on the species life history and on
data availability. Population models can roughly be classified as age/size structured or
biomass-based; deterministic or stochastic; density- dependent or density-independent;
spatially-structured or spatially aggregated; equilibrium or non-equilibrium.
Pop-up Tag: A tag that detaches itself from the fish after a predetermined period of time
has elapsed since tagging. After detachment, the tag sends a signal via satellite,
providing its position and downloading any other available information (if the pop-up
tag is also an archival one). This technology does not rely on the recapturing/reporting
of tagged fish to recover the information. (de Metrio et al. 1999)
Precautionary Approach: “A set of agreed cost-effective measures and actions,
including future courses of action, which ensures prudent foresight, reduces or avoids
risk to the resource, the environment, and the people, to the extent possible, taking
explicitly into account existing uncertaintiesand A population the potential
consequences of being wrong" (García, 1996)
Production Model: A model that describes, using simple functions, how the population
biomass changes from year to year (or, how biomass changes in equilibrium as a
function of fishing mortality). The simplest production functions aggregate all of the
biological characteristics of growth, natural mortality and reproduction into a simple,
deterministic model using three or four parameters. Production models are primarily
used in simple data situations, where total catch and effort data are available but age-
structured information are either unavailable or deemed to be less reliable (although
some versions of production models allow the use of age structured data). (Cadima and
Pinho 1996)
Quota: A portion of a TAC allocated to a fishery or to an operating unit, such as a size
class of vessels or a country.
Rebuilding: Refers to the trajectory of a stock from an overfished condition to a defined
target. For example, a stock may be rebuilt to the BMSY level.
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Recruitment: the amount of fish that first become vulnerable to the fishery each year due
to growth and/or migration into the fishing area.
Recruitment Overfishing: The rate of fishing above which the recruitment to the
exploitable stock becomes significantly reduced. This is characterized by a greatly
reduced spawning stock, a decreasing proportion of older fish in the catch, and
generally very low recruitment year after year. Recruitment overfishing can lead to
stock collapse.
Spawning Potential Ratio (SPR): The ratio of spawning potential per recruit under a
given fishing regime relative to the spawning potential per recruit with no fishing (also
known as %MSP for Maximum Spawning Potential). SPR‟s require information on
natural mortality, growth, spawning potential at age and the relative vulnerability by age
to fishing. If possible, spawning potential per recruit is measured in fecundity per
recruit, but often spawning stock biomass per recruit (SSB/R see below) is an
appropriate substitute. SPR and SSB/R are simple extensions to yield per recruit (see
below) in that there are two ways in which recruits can be used: they can be caught, in
which case they are part of the yield (yield per recruit), or they can survive, in which
case they are part of the SPR, SSB/R. SPR is expressed as a ratio of a fished condition
to an unfished condition, thus the ratio varies from 0 to 1. Additionally, empirical
studies have shown that for some populations SPR‟s in the order of 20% to 30% may
run the risk of recruitment declines, thus there is a basis of comparison between
populations. Therefore, FX%SPR fishing mortality rates are sometimes used as
biological reference points. (Note: SPR is sometimes used to mean “spawners per
recruit”, but this usage should be avoided and replaced by SSB/R). (Goodyear 1990)
Spawning Stock Biomass (SSB): The total weight of sexually mature fish in the
population (usually males and females combined, but sometimes female SSB, alone, is
used). This quantity depends on the abundance of year classes, the exploitation pattern,
the rate of growth, both fishing and natural mortality rates, the onset of sexual maturity,
and environmental conditions. Many types of analyses that address reproductive
(spawning) potential should use a measure of production of viable eggs (e.g. fecundity).
However, when such life-history information is lacking SSB is used as a proxy.
Stock: The term has different meanings. In general, a stock is a biological unit of one
species forming a group of similar ecological characteristics and, as a unit, is the subject
of assessment and management. However, there are many uncertainties in defining
spatial and temporal geographical boundaries for such biological units that are 100%
compatible with established data collection and geopolitical systems. For this reason,
the term stock is often synonym with assessment/management unit, even if there is
migration of the same species to and from adjacent areas.
Stock Assessment: The application of statistical and mathematical tools to relevant data
in order to obtain a quantitative understanding of the status of the stock as needed to
make quantitative predictions of the stock´s reactions to alternative future regimes.
Stock-Recruitment Relationship: A function that describes how recruitment varies with
changes in the reproductive output (or biomass) of the parental stock. Two common
forms are the Beverton- Holt and the Ricker relationships. The stock-recruitment
relationship is particularly important for the understanding of the sustainability of
alternative harvesting regimes. Some stock assessment methods incorporate the
estimation of such a relationship directly into the model, either explicitly (e.g. some
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age-structured assessments) or implicitly (most stock production models). (Hayasi
1974)
Stock Structure: (1) Refers to the geographical boundaries of the stocks assumed for
assessment and management purposes (e.g. a species may be assumed to be comprised
of three separate stocks in the North Atlantic, South Atlantic, and Mediterranean Sea).
(2) Refers to boundaries that define self-contained populations in a genetic sense.
Total Allowable Catch (TAC): A management control to limit the catch (yield) for the
entire stock. TACs are typically partitioned into quotas.
Related policy and guidance framework; decision making-architecture and
considerations
ICCAT is responsible for collecting and analyzing statistical information relating to
the current conditions and trends of the tuna fishery resources of the Convention area,
studying and appraising information concerning measures and methods to ensure
maintenance of the populations of tuna and tuna-like fishes in the Convention area at
levels which will permit the maximum sustainable catch and which will ensure the
effective exploitation of these fishes in a manner consistent with this catch. ICCAT
recommends studies and investigations to the Contracting Parties and publishes and
disseminates reports of its findings and statistical, biological and other scientific
information relative to the tuna fisheries of the Convention area.
According to the Convention ICCAT should submit a report to the Contracting
Parties on its work and findings every two years, while in practice reports are published
annually. The ICCAT biennial reports comprise Volumes 1 and 2, where each volume
corresponds to a one year period.
National application of the precautionary approach to fisheries management
The ICCAT takes into account the principles of the Precautionary Approach in setting
its biological reference points and control rules.
The precautionary approach, is firmly incorporated in UNFSA as one of the general
principles for the conservation and management of straddling fish stocks and highly
migratory fish stocks (Arts. 5(c), 6 and Annex II). Article 6 and Annex II contain detailed
provisions on the application of the principle, including the following:
States shall be more cautious when information is uncertain, unreliable or inadequate;
the absence of adequate scientific information shall not be used as a reason for
postponing or failing to take conservation measures;
States shall improve decision-making for conservation and management by obtaining
and sharing the best scientific information available and implementing improved
techniques for dealing with risk and uncertainty;
States shall determine stock-specific target and limit reference points and the action to
be taken if they are exceeded;
For new or exploratory fisheries, States shall adopt cautious measures until there are
sufficient data to allow the identification of measures for the long-term sustainability
and gradual development of fisheries;
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The Code of Conduct, in Article 7.5, calls upon States to apply the precautionary
approach widely to conservation, management and exploitation of not only certain
specific species but of all aquatic resources, in order to protect them and preserve the
aquatic environment. The same article also contains provisions similar to those in
UNFSA quoted above.
The ICCAT Convention itself has no provision regarding the precautionary approach;
ICCAT has not adopted the precautionary approach as such, though various measures it
has adopted are based on some of the ideas contained in the above-quoted provisions of
UNFSA.
In the 2009 Independent Performance Review of ICCAT, it was noted that all RFMO
conventions adopted or amended recently make the application of the precautionary
approach obligatory to Contracting Parties such as the WCPFC Convention, Arts. 5 (c), 6,
Annex II; SEAFO Convention, Arts. 6 (g) and 7: Antigua Convention, Art. IV; Amended
NAFO Convention, Art. III (c); New NEAFC Convention, Art. 4 (2) (b); and Southern
Indian Ocean Fisheries Agreement (SIOFA), Art. 4 (c)). Most of these conventions
incorporate the contents of Article 6 and Annex II of the UNFSA into their own regime
by making direct reference to those provisions. In the light of these developments among
RFMOS, as well as the wide-spread adoption of the concept in practice, the Independent
Performance Review Panel strongly recommended that ICCAT formally and
systematically adopt the precautionary approach.
Scientific framework
Guidelines for the use of reference points and associated target variables
ICCAT uses modeling to develop reference points and indicators that incorporate
ecosystem considerations and to develop simulation, dynamic and statistical models
focused on mixed-fisheries, multi-species, by-catch and ecosystem issues.
There is not a unanimous agreement on MSY and related benchmarks, for the
following reasons:
Fishing near MSY means that spawning populations will be mostly made up of first
time spawners which will create instability in recruitment.
Fish populations are generally made up of distinct subpopulations adapted to their local
environment. Fishing is likely to remove the most productive subpopulations first
which means that MSY would be expected to decrease over time.
It is likely to be very difficult to implement measures that would achieve MSY in multi-
species
fisheries, particularly given predator-prey relationships that may change in space and
time.
Maximum economic yield generally occurs with fishing effort (or fishing mortality)
that is less than those corresponding to MSY.
Because of these and other concerns, the UNFSA Annex II, which provides
guidelines for the application of precautionary reference points, in paragraph 7 states that
“The fishing mortality rate which generates maximum sustainable yield should be
regarded as a minimum standard for limit reference points. For stocks which are not
overfished, fishery management strategies shall ensure that fishing mortality does not
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exceed that which corresponds to maximum sustainable yield, and that the biomass does
not fall below a predefined threshold. For overfished stocks, the biomass which would
produce maximum sustainable yield can serve as a rebuilding target.”
Approaches and guidelines regarding data poor situations, risk and uncertainty
Accurate and timely catch and effort data is necessary for international organizations
to effectively manage fisheries. A consistent theme in a large number of the ICCAT
reports and in reports from the SCRS to ICCAT is that data provision is unreliable,
inaccurate and not provided within the required time frame. Data deficiencies in ICCAT
are summarized in document SCRS/2003/021. “Overview of Data Deficiencies at
ICCAT”. Work is underway to build capacity and understanding in developing countries
on the requirements to provide timely and accurate data. However, many developed
countries do not submit data in a timely manner.
The Independent Performance Review of ICCAT Panel recommended strongly that
such misreporting stop immediately, that CPCs collect and report Task I and Task II data
in a timely manner within the agreed time limits, that effort should be continued to build
capacity in developing CPCs and improve reporting by developed CPCs, and CPCs who
continually fail to comply should be subject to an appropriate penalties regime.
Rebuilding plans
Structure and composition of rebuilding plans
ICCAT utilizes time-area closures, reporting of total catch, and quota allocations for
Contracting Parties or cooperating non-Contracting Parties, entities, and fishing entities.
The Rebuilding Plan for North Atlantic Swordfish consists of lowered TACs, the
elimination of dead discard allowance in 2004, and quotas, in an effort to achieve MSY
within the ten-year span of the Rebuilding Plan. Unused portions and excess of the annual
quota or catch limit are automatically deducted from the subsequent year‟s quota or catch
limit.
Review and evaluation process
At its 2007 annual meeting of ICCAT it was agreed to conduct an independent review
of its own performance against its objectives. An independent panel of specialists
undertook a broad review of ICCAT‟s performance and made recommendations
concerning approaches to strengthen the mandate of ICCAT and improve its
performance. The analysis and recommendations were published in a report in 2010.2
According to this panel review ICCAT has developed reasonably sound conservation
and fisheries management practices which would have been effective had Contracting
Parties, Cooperating non-Contracting Parties, Entities and Fishing Entities fully
implemented and complied. According to the reviewers those problems are not uniquely
to ICCAT but also to other tune RFMOs. However the size of the ICCAT membership
adds difficulties.
2 www.iccat.int/Documents/Other/PERFORM_%20REV_TRI_LINGUAL.pdf
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Application of an ecosystem approach to fisheries
Through research, ICCAT evaluates the relative impact of the different abiotic and
biotic factors including oceanographic and climate phenomena, directed and incidental
fishing, predation, competition, pollutions and other human impacts that affect the
abundance, distribution and migration of ICCAT target species, and characterizes the
main feeding and reproductive habitats of ICCAT target species. ICCAT characterizes the
volume, composition, and disposition of non-target species that are caught incidentally in
tuna and tuna-like fisheries within the Convention area in order to investigate trophic
interactions of ICCAT target species and the impact that changes in fishing gears or
fishing technology have on the catch of target and non-target species.
Mechanisms are developed which can be used to better integrate ecosystem
considerations into the scientific advice provided by SCRS to the Commission, including
but not limited to, Precautionary Approaches, to investigate, through operational models,
potential benefits (at an ecosystem level) of alternative management strategies, such as
time-area closures, and to advise on the impacts of tuna and tuna-like fisheries on the
populations of non-target species of interest to the Commission.
Monitoring and compliance regime under rebuilding plans
Compliance matters are reviewed by two different bodies: The Conservation and
Management Measures Compliance Committee and the Permanent Working Group on
ICCAT Statistics and Conservation Measures.
The ICCAT aims to monitor the conservation of tunas and tuna-like species in the
Atlantic Ocean and adjacent seas by creating and monitoring an inventory of species
caught by fleets targeting tuna and tuna-like species in the Atlantic and Mediterranean, by
improving conventional statistics such as catch, effort, and size of ICCAT target species
that are caught incidentally in non-targeted fisheries, monitoring and improving
information on interactions with non-ICCAT target species with emphasis on those
species of interest to the ICCAT and for which no Species Group has been established,
such as sea turtles and sea birds, and by facilitating access to scientists from the Standing
Committee on Research and Statistics and oceanographic and environmental data.
Contracting Parties whose landings exceed the catch limit must provide an
explanation to the Compliance Committee detailing how overharvest occurred and
actions already taken or to be taken in order to prevent further overharvest. Should a
Contracting Party exceed its catch limits during any two consecutive management
periods, its catch limit will be reduced in the next subsequent management period by
100% of the amount in excess of the catch limit, and ICCAT may authorize other
appropriate measures such as a reduction in the catch limit equal to a minimum of 125%
of the excess harvest, and if necessary, trade restrictive measures. Trade measures
enforced under this clause will be import restriction on the subject species and consistent
with each Party‟s international obligations.
For any species under quota or over the catch limit, underages and overages from one
year may be added to or must be subtracted from the quota or catch limit of the
management period immediately after or one year after that year, unless any
recommendation on a stock specifically deals with overages or underages, in which case
that recommendation will take precedence.
ICCAT has a joint inspection scheme in which inspections are carried out by
inspectors of the fishery control services of Contracting Parties. Compliance with ICCAT
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Conservation and Management Measures is monitored by Contracting Parties, who are
obliged to collect information regarding non-compliance, such as sightings of vessels
which exceed the legal length, vessel which appear to be fishing bluefin tuna in the North
Atlantic without regard for the scientific monitoring quota, or directing fisheries on
spawning stocks in the Gulf of Mexico, fishing bluefin tuna in areas contrary to ICCAT‟s
recommendations. Contracting Parties should also encourage other fishermen to gather
information and report their findings. Vessels in question that fly the flag of a Contracting
Party will be referred to appropriate authorities of that Contracting Party, who will
proceed with the appropriate actions. Vessels in question who do not fly the flag of a
Contracting Party will be referred to the relevant non-Contracting Party, and a request
will be made for prompt appropriate actions to be made, so as not to undermine the
effectiveness of the ICCAT Conservation Measures. The Commission will be notified in
such cases.
Contracting Parties are encouraged to board pelagic fishing vessels of non-
Contracting Parties in the Convention Area upon the consent of the master, in order to
collect sighting information such as the vessel type and name, the flag, port of registry,
the international radio call sign, registration number, and other relevant tracking
information.
Economic aspects
While ICCAT Basic Texts make no provision for market-based measures, ICCAT has
adopted several market or trade-related measures to combat IUU fishing, namely The
Recommendation Concerning ICCAT Bluefin Tuna Statistical Document Program which
established the Bluefin Statisical Document Program, which states that all tuna imports
into Contracting Parties must be accompanied by a Bluefin Statisical Document (BSD).
This recommendation was further expanded to include swordfish, bigeye and other
species. In 2007, the new Recommendation on an ICCAT Bluefin Catch Documentation
Program replaced the BSD program with the bluefin catch documentation (BCD)
program, which came into effect June 2008. Under the new recommendation, Contracting
Parties shall require a completed BCD for each bluefin tuna landed at its ports, delivered
to its farms, and harvested from its farms. Each consignment of bluefin tuna domestically
traded, imported into or exported or re-exported from its territories must be accompanied
by a validated BCD and, as applicable, an ICCAT transfer declaration or a validated
Bluefin Tuna Re-export Certificate (BFTRC). BCD forms are provided by CPCs to only
vessels authorized to harvest bluefin tuna in the Convention area, and the BCD must be
validated by an authorized government official, or other authorized individual or
institution. The BFTRC must also be validated by an authorized government official.
Each CPC shall communicate a copy of all validated BCDs or BFTRCs, as a rule within
five working days, to the authority of the country where the bluefin tuna will be
domestically traded, or transferred into a cage or imported, as well as to the ICCAT
Secretariat. This newly implemented BCD program is expected to be much more
effective in deterring IUU fishing than the previous BSD program in excluding IUU
products from major markets and thus discouraging IUU fishing.
Further, since 1996, ICCAT has adopted several measures banning the import of
Bluefin tuna, Bigeye tuna, and swordfish, and their products from those countries whose
vessels were identified as fishing such species in a manner which diminishes the
effectiveness of ICCAT measures. Most of such sanctions were lifted subsequently, when
the Commission found that fishing practices of the countries concerned were brought into
INTERNATIONAL COMMISSION FOR THE CONSERVATION OF ATLANTIC TUNAS (ICCAT) – 21
INVENTORY OF NATIONAL AND REGIONAL APPROACHES TO FISHERIES REBUILDING PROGRAMMES © OECD 2012
conformity with ICCAT measures. The recently adopted Recommendation Concerning
Trade Measures sets out detailed, step-by-step procedures for deciding the imposition of
trade restrictive measures, so that they are taken as a last resort, and implemented in
accordance with international law, including WTO rules, in a fair, transparent and non-
discriminatory manner.
Key documents and references
International Commission for the Conservation of Atlantic Tunas (2001), Sailfish,
www.iccat.int/Documents/SCRS/ExecSum/SAI_EN.pdf, accessed 18 August, 2009.
--- (2006) Compendium of ICCAT Management Recommendations and Resolutions,
www.Iccat.Int/Documents/Recs/Ple-012%20eng.Pdf", accessed 18 August, 2009.
--- (2006), Field Manual, www.iccat.int/Documents/SCRS/Manual/CH1/CH1-ENG.pdf, accessed
18 August, 2009.
--- (2007), Basic Texts www.iccat.int/Documents/Commission/BasicTexts.pdf, accessed 18
August, 2009.
--- (2007), Blue Marlin and White Marlin, www.iccat.int/Documents/SCRS/ExecSum/BUM-
WHM_%20EN.pdf, accessed 18 August, 2009.
--- (2008), Atlantic Bluefin Tuna, www.iccat.int/Documents/SCRS/ExecSum/BFT_EN.pdf,
accessed 18 August, 2009.
--- (2008), Compendium Management Recommendations And Resolutions Adopted By ICCAT
For The Conservation Of Atlantic Tunas And Tuna-Like Species,
www.iccat.int/Documents/Recs/ACT_COMP_2008_ENG.pdf, accessed 18 August, 2009.
--- (2008), International Commission for the Conservation of Atlantic Tunas Report for Biennial
Period 2006-2007, www.iccat.int/Documents/BienRep/REP_TRI%20LINGUAL_06-
07_II_3.pdf, accessed 18 August, 2009.
--- (2008), Mediterranean Swordfish, www.iccat.int/Documents/SCRS/ExecSum/SWO-
MED_EN.pdf, accessed 18 August, 2009.
--- (2009), Albacore Tuna, www.iccat.int/Documents/SCRS/ExecSum/ALB_EN.pdf, accessed 18
August, 2009.
--- (2009), Atlantic Swordfish, www.iccat.int/Documents/SCRS/ExecSum/SWO-ATL_EN.pdf,
accessed 18 August, 2009.
--- (2009), Bigeye Tuna, www.iccat.int/Documents/SCRS/ExecSum/BET_EN.pdf, accessed 18
August, 2009.
--- (2009), Pelagic Sharks, www.iccat.int/Documents/SCRS/ExecSum/SHK_EN.pdf, accessed 18
August, 2009.
--- (2009), Report of the Independent Performance Review of ICCAT,
http://www.iccat.int/Documents/Other/PERFORM_%20REV_TRI_LINGUAL.pdf, accessed 2
September, 2009.
--- (2009), Skipjack Tuna, www.iccat.int/Documents/SCRS/ExecSum/SKJ_EN.pdf, accessed 18
August, 2009.
--- (2009), Small Tunas, www.iccat.int/Documents/SCRS/ExecSum/SMT_EN.pdf, accessed 18
August, 2009.
--- (2009), Yellowfin Tuna, www.iccat.int/Documents/SCRS/ExecSum/YFT_EN.pdf, accessed 18
August, 2009.
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