The majority of the worlds fishery resources are being
subjected to overfishing as stocks* are reduced to below safe
levels associated with long-term, sustainable and efficient production.
Stocks exploited beyond maximum sustainable limits are at high
risk of depletion and collapse.
* The elements of world fishery resources that
we call "stocks" are generally conglomerates of stocks (and often
of species). Stocks may be classified as underexploited, moderately
exploited, fully exploited, overexploited, depleted or recovering,
depending on how far they are in terms of biomass and fishing
pressure from the levels corresponding to full exploitation.
Of course, overfishing is not just a case of depleting the natural
renewable capital on which commercial marine capture fisheries
depend. The removal of huge quantities of fishes from the oceans
has both direct and indirect impacts on entire marine ecosystems,
for example, by altering predator-prey relationships, food web
structures, nutrient cycling, marine mammal survival, seabird
breeding success, and so forth. (See Fisheries
Overfishing is not a recent phenomenon. It was recognised in
the North Atlantic as long ago as the early 1890s and was the
subject of the London Conference on Overfishing in 1946. It has
since become prevalent in most of the world's fishing areas, affecting
marine capture fisheries in developing and developed countries
alike. It is usually most severe adjacent to densely populated
coastal zones and in biologically productive offshore areas.
The majority of the world's fishery resources are being subjected
to exploitation at or above their capacity to produce maximum
sustainable yields (MSY). About 75% of the world's most valuable
marine fish stocks are either fished to the limit or else overfished.
Looked at another way, about
28% of the world's fish stocks are below the level of abundance
represented by the MSY level of biomass and require fisheries
management action aimed at rebuilding them to at least the MSY
The Food and Agriculture Organization of the United Nations (FAO)
has estimated that the maximum production for world marine capture
fisheries, under the present overall fishing regime (generally
characterised by capture of small juvenile fish and significant
discards), corresponds to about 82 million tonnes per year (FAO
1997a). An additional 20 million tonnes of annual landings might
be obtainable worldwide, provided that 1) depleted resources are
rehabilitated, 2) under-developed resources are exploited further,
whilst avoiding their overfishing and the overfishing of fully
exploited resources, and 3) discarding and other wastage are reduced
However, the 1999 world marine capture fisheries production was
in fact about 84 million tonnes. In 2002 this had risen to 93.2
million tonnes (FAO 2004).
According to the FAO (2004), among the world's major marine fish
stocks or groups of stocks for which information is available,
- An estimated 3% are underexploited and 21% moderately exploited.
These stocks may have the potential to produce more under increased
- About 52% of stocks are fully exploited and, therefore, are
producing catches that have either reached or are very close
to their maximum limits, with no room expected for further expansion.
Stocks that are fully exploited are considered as being exploited
at levels close to their MSY. These stocks are in need of (and
in some cases already have) effective measures to control fishing
- Another 16% are overexploited (i.e. clearly fished beyond
their MSY) and have no potential for further increase. Moreover,
there is an increasing likelihood that catches from overexploited
stocks will decrease if remedial action, such as capacity reduction,
is not taken to reduce or revert overfishing conditions.
- About 7% of stocks have been depleted (by exploitation beyond
their MSY). The remaining 1% are recovering from depletion.
Such stocks have potential for recuperation and stock rebuilding,
provided that drastic management measures are adopted in order
to revert uncontrolled and excessive fishing pressure as well
as any other condition that could have contributed to the stock's
overexploitation or depletion.
Even where directed fishing pressure on recovering stocks may
have been reduced (by management or lack of profitability), these
stocks may still be under excessive fishing pressure, including
as a result of their exploitation as bycatch in another fishery.
in the North-East Atlantic
Over a thousand species of fish have been recorded in the North-East
Atlantic (i.e. the OSPAR marine area) with some 700 species
occurring in the waters around Ireland and adjacent seas (OSPAR
Region III Celtic Seas).
About 5-10% of these species are either targeted directly by
the commercial fishing industry or otherwise caught incidentally
as bycatch. The biodiversity of the open ocean west of the European
continental shelf (OSPAR Region V Wider Atlantic) is less well
quantified, particularly in deeper waters, but fewer species are
likely to occur than over the continental shelf.
|OSPAR Commission management regions
The 1998 stock status of the main commercially exploited species
around Ireland are given in Table
The larvae of many commercially important fish
species disperse into the open ocean from their spawning grounds
over the continental shelf and in estuarine areas. Some fish species
perform long annual migrations between the feeding, spawning and
overwintering areas. Variability in stock recruitment is related
to both the size of the parental stock and to a number of factors,
including environmental variability and predation, which affect
egg and larval survival.
Many deep-water species have an extensive geographical distribution
owing to the small environmental variations of their habitat.
In the Wider Atlantic, top predators such as sharks probably play
an important role in maintaining the structure and diversity of
fish assemblages. Large pelagic predators, such as tuna and marlin,
are highly migratory, ranging far beyond the boundaries of the
It is thought that the maximum
potential annual production for marine capture fisheries in the
North-East Atlantic (FAO Statistical Area 27) is about 12 million
tonnes. During the late 1980s and early 1990s annual catches in
the region were approximately 10 million tonnes. The 1998 catch
was 10.9 million tonnes.
Since the 1950s the proportion
of the total North-East Atlantic catch that is made up of historically
valuable or traditional species such as cod, haddock and herring
has declined, while catches of many formerly lower-valued species
such as sandeels and blue whiting have increased.
In 1997 the FAO reported that most of the traditional fishery
resources of the North-East Atlantic were fully exploited or overexploited,
with several stocks in a depleted condition. "The root cause of
this poor situation within European waters has been the inability
of the member states within the European Union (EU) to control
and reduce fleet capacity within the Common Fisheries Policy"
In its Quality Status Report
2000 of the North-East Atlantic, the OSPAR Commission states that
many target species are now outside their "safe biological limits"
. Fishing is particularly intensive
in the North Sea, with around 50-60% (but up to 60-70% in some
cases) of the total biomass of the main commercial stocks removed
each year. Fishing on this scale is clearly unsustainable and
threatens the integrity of the marine ecosystem, resulting in,
for example, the modification of predator-prey relationships.
In 1999 the International
Council for the Exploration of the Sea (ICES) reported that
40 out of 60 major commercial stocks in the North-East Atlantic
were outside safe biological limits or, in other words, heavily
overfished (OSPAR 2000). In the same year a scientific assessment
of EU fish stocks judged 67% to be overfished, 40% depleted, and
37% of species suffered from both problems (CEC 2000). ICES has
also estimated that mature demersal fish (i.e. fish living close
to the seabed) decreased by about 90% between the early 1970s
and late 1990s (CEC 2001).
In the North-East Atlantic about
83% of stocks are consistently being exploited at or beyond MSY
levels  Perhaps the most severely
struck species has been cod. In the EU the average yearly landings
over the period 1995-1999 were down 65% compared to 1978-1982.
Numbers of larger, mature cod (vital for spawning to replenish
stocks) have fallen by 73% in the same period (CEC 2001). One
of the areas in which the situation is worst is in the Irish Sea.
As a consequence of continuous
overfishing, total allowable catches (TACs) for northern hake
have been slashed from 21,120 tonnes in 1997 to a little over
7,000 tonnes in 2001; while quotas for herring off Western Scotland
have been cut from over 83,000 tonnes in 1998 to just above 30,000
It is highly likely that squid are vulnerable to pressure from
exploitation. The biology of squid is not well known despite being
very abundant, especially in the Wider Atlantic. Only a few species
are exploited commercially, but squid are of considerable ecological
importance as predators, and as the food of some whales, fish
in OSPAR Region III (Celtic Seas)
Stock assessment is designed
to improve understanding of the dynamics of exploited species
and involves the estimation of parameters such as mortality rates
(due to fishing and other causes), numbers in age groups (year
classes) and recruitment, growth rates and spawning stock biomass.
The state of the main commercially
exploited stocks of fish and shellfish in OSPAR Region III (Celtic
Seas) is assessed annually by scientists in the bordering countries,
under the coordination of the ICES Advisory Committee on Fisheries
Management (ACFM). For some stocks and/or sub-areas, sampling
levels are generally too low for reliable assessments to be made.
In 1997 seven stocks were considered by ICES to be "close to
or outside safe biological limits" and consequently their status
is a matter of concern. These were: cod in division VIa, whiting
in divisions VIIe-k, northern hake in all divisions, saithe in
sub-area VI, plaice in VIIf+g and sole in VIIa and VIIf+g .
ICES ACFM has also recommended significant reductions in the exploitation
rates of salmon stocks.
In 1997 the FAO reported that:
- Cod stocks of the West of Scotland, Rockall,
Irish Sea and Celtic Sea are all considered to be outside safe
biological limits to varying degrees. FAO experts advised reductions
in fishing mortality.
- The West of Scotland and Rockall saithe
stock is considered outside safe biological limits, with spawning
stock biomass (SSB) close to the record low level of 1992. FAO
experts advised the maintenance of low levels of fishing mortality.
- Catches of Irish Sea plaice have generally
been below advised TACs since 1988, but the SSB declined below
average levels in 1990 and has yet to recover significantly.
- FAO experts advised a 20% reduction in
fishing mortality of Irish Sea sole.
- The Celtic Sea plaice and sole stocks
are considered to be near safe biological limits. FAO experts
advised a 20% reduction in fishing mortality.
- Mackerel may be outside safe biological
limits and FAO experts advised a significant reduction in fishing
- The Northern hake are found from the Bay
of Biscay to the Celtic, Irish and North Seas. The stock is
considered to be outside safe biological limits and FAO experts
advised a 30% reduction in fishing mortality and improved enforcement
of mesh size and minimum landing size regulations. ICES recommended
a significantly reduced fishing mortality since stock rebuilding
is urgently required, especially in the southern region. A large
number of under-sized fish are caught and these are usually
discarded (FAO 1997a).
It is very important that fishing is managed
in a sustainable way to avoid overexploitation of the fish stocks
and to rebuild those stocks that are believed to be overexploited
In 2000 the OSPAR Commission stated that
many of the commercial fish stocks within Region III are heavily
exploited. Of the 35 stocks assessed in the region, the spawning
stocks of 13 are low compared to their averages over the periods
for which data are available. Of these, five stocks show a downward
trend and the remainder have been stable over recent years. The
stock size and recent trends of nine stocks are unknown.
OSPAR (2000) adds that: "Poor catch statistics and a lack of
biological data severely hamper assessment of the horse mackerel
stock and there are uncertainties about its current status. Underreporting
and misreporting in division VIa, whereby fish caught in the assessment
area are reported as being caught in another, affects the reliability
of assessments of the cod fishery."
In 2001 the European Commission reported
on the state of the European Union's fishery resources and their
expected development in its Green Paper on the future of the Common
Fisheries Policy (CEC 2001):
- The Irish Sea (ICES area VIIa): The Irish Sea cod stock is
an "emergency situation" and strong management action was imposed
in 2000. The whiting stock is also in a "critical state". The
flatfish stocks have stabilised "but at a lower level than in
the past" and fishing mortalities have been reduced.
- Celtic Sea, West Channel and the northern
part of Bay of Biscay (ICES areas VIIf-k and VIIIa+b+d+e): Cod
in area VIIe-k "will approach a critical state" if fishing mortality
is not reduced. Whiting in area VIIe-k appears to have an improvement
in spawning stock biomass (SSB) with decreasing fishing mortality,
but fishing mortality seems to have increased in recent years.
Almost all flatfish stocks such as plaice VIIf+g and sole VIIf+g
are "heavily exploited" but some stocks such as anglerfish and
megrim are stable or fluctuating. Most of the herring stocks
in this area are increasing or stable such as herring in Celtic
- Widely distributed stocks (ICES areas
II to IX): Stocks such as mackerel, blue whiting and northern
hake straddle several of the above-mentioned areas. Among these
stocks the development for northern hake and recently blue whiting
"is of most concern". Mackerel, as most other pelagic stocks,
shows a stable and possibly a sustainable trend.
In regions where commercial stocks have been
overexploited, fishing pressure is often switched to stocks in
other areas, including deep-sea populations. The slow growth rates
and low fecundity of many deep-sea fish makes them especially
vulnerable to overexploitation. Evidence is beginning to emerge
that deep-sea trawling inflicts damage upon some of the deeper
ecosystems. These impacts may already be quite extensive and recovery
can be relatively slow.
of Europe's stocks
Regarding the current state
of the main European Union (EU) fish stocks, Annex 1 of the European
Commission's May 2002 "roadmap" on the reform of the CFP (CEC
The quantities of mature demersal fish in the sea, as assessed
by ICES, have in many cases "declined significantly" over the
last 25 years. On average, these quantities were about 90% greater
in the early 1970s than in the late 1990s. The general decline
in landings is similar. "For some stocks such as cod even more
drastic reductions in mature fish have occurred". The biomass
of pelagic and industrial species increased by, on average, 20%
since the late 1970s and mid-1980s at least in part following
the recovery of herring from the low levels of the late 1970s.
The overall trend is of an increased proportion of the stocks
being taken each year, which has led to the "erosion of the quantities
of mature fish". In recent years for many stocks the quantities
of mature fish in the sea have been "below or very close to the
minimum levels required to provide high probability of sustainability
(precautionary levels of stock biomass)," whereas historically
they tended to be above such levels. Similarly, many stocks have
been subject to a level of fishing mortality rate "in excess of
precautionary levels" whereas, historically, the fishing mortality
rate was less than the precautionary level.
"From a biological point of view, the sustainability of a high
number of stocks will be threatened if the current levels of exploitation
are maintained and, at present, this risk is highest for demersal
round fish stocks which are of high commercial value." The situation
is better for pelagic stocks. Stocks of small pelagic species
(herring, sprat, mackerel, horse mackerel, anchovy, sardine) and
species which support industrial fisheries (Norway pout, sandeels)
have generally not deteriorated over the last 20 years and especially
not over the 10 ten years.
In the case of benthic resources (Nephrops, flatfish)
"a general economic overexploitation pattern can be observed"
but at the biological level the situation cannot be considered
as systematically serious.
Finally, there are also resources such as skates and rays, and
the minor flatfish species (including turbot, brill, lemon sole,
witches, dabs) that are not subject to detailed scientific follow-up
"but which may also be overexploited". The situation varies from
one zone to another, especially in terms of apparent evolution
of fishing mortality in the mid- to long-term.
"In the Baltic, the current situation does not seem to be sustainable.
In the North Sea, it has not been possible to reverse the decline
of round fish stocks nor to ensure in the case of sole and plaice
a security margin in accordance with the precautionary principle
which would have also improved the economic situation for these
fisheries. In Western waters, fishing mortality rates have been
increasing catching up with and often exceeding historical levels
observed in the North Sea. In the Mediterranean, the available
scientific data are less complete but there is a large consensus
that many important stocks are being over-fished."
To sum up, the Commission states that: "many stocks are at present
outside or almost outside safe biological limits. They are too
heavily exploited or have low quantities of mature fish or both.
At present, the situation for most stocks is not catastrophic.
If current trends continue, however, many stocks will collapse.
Improvement in the state of many fish stocks is urgent."
Stocks for which scientific
advice recommends recovery plans include:
- Blue whiting (combined stock, I-IX, XII and XIV)
- Northern hake in Western waters (Vb, VI, VII, XII, XIV)
- Cod in North Western waters (Vb, VI, XII, XIV)
- Cod in the Irish Sea (VIIa)
- Cod in western waters (VIIb-k, VIII, IX, X, CECAF)
- Whiting in the Irish Sea (VIIa)
- Haddock in the Irish Sea (VIIa)
Other stocks outside safe biological limits include:
- Anglerfish in western waters (Vb, VI, XII, XIV)
- Anglerfish in the West of Ireland (VII)
- Horse mackerel in the West of Scotland, West of Ireland and
Bay of Biscay (Vb, VI, VII, VIIIabde)
- Sole in the Celtic Sea (VIIfg)
- Plaice in the Celtic Sea (VIIfg)
Root causes of
The problem of overfishing typically arises in the economic and
political environment provided by open, market-driven economies.
The FAO states that: "An essential characteristic of most fisheries,
and of some aquaculture production systems, is that they make
much use of common, non-priced resources, the access to which
is not effectively limited. As a result, fishermen and aquaculturists
often exploit the commonly held resources beyond what would be
efficient in the long run for the community as a whole. In the
process, they impose often unknowingly costs on
others, both inside and outside the fishery sector, including
leisure fishers and non-consumptive users of the marine environment.
This latter category of users is becoming increasingly vocal in
its advocacy that capture fisheries, and aquaculture when relevant,
should be made accountable for the costs they impose on others
through their impact on the environment" (FAO 1997b).
Clearly, governments must intervene to provide guidance to fishermen
and aquaculturists on what constitutes economically and socially
efficient, long-term levels of fisheries effort. "This is a difficult
task because fishermen and aquaculturists see themselves as being
asked to bear the immediate costs, with little prospect of sharing
in the long-term benefits; that is, they perceive guidance by
government as an attempt to reallocate their income to others"
Consistent with a precautionary
approach to fisheries management, the ICES ACFM sets precautionary
levels (reference points) for fishing mortality rates and spawning
stock biomass, beyond which the stock is considered to be outside
"safe biological limits" and the fishery to be unsustainable.
One such reference point is
the "minimum biologically acceptable level" (MBAL). This is the
level of spawning stock biomass below which the probability of
poor recruitment (i.e. the production of offspring/recruits) increases
as the spawning stock decreases. MBAL is not a target for management
but rather an indicator of a situation that may threaten the future
sustainability of the stock.
Other criteria that indicate
when a stock is outside safe biological limits include the age
structure and distribution of the stock (a decrease in stock size
may be accompanied by a decrease in the area occupied by the stock)
and exploitation rates. A fishery that maintains stock size within
a precautionary range (a range within which the probability of
reaching any limit is very small) would be expected to be sustainable.
It should be noted, however, that the numerical values of the
reference points used to define safe biological limits may change
as biological characteristics of the stock change, or as new information
becomes available (OSPAR 2000).
Exceeding the TAC
Agreed annual catch limits, known as the "Total Allowable Catch"
(TAC) for a fish stock, are the principle means by which commercial
fishery resources have been managed in EU waters under the Common
Fisheries Policy (CFP) framework (see How
are TACs and quotas set?). However, many fisheries experts
believe the TAC system contributes to long-term overfishing. The
FAO has highlighted "the fact that catches often exceed agreed
TACs, that agreed TACs often exceed those advised by ICES, and
that advised TACs have been based on uncertain, and often optimistic
stock assessments" (FAO 1997a). This is corroborated by the European
Commission, which stated in its Green Paper on the future of the
CFP that: "The current situation of resource depletion results,
to a good extent, from setting annual catch limits in excess of
those proposed by the Commission" (CEC 2001).
Under the TAC system, the European
Commission reviews scientific advice from ICES and proposes TACs
for certain commercial stocks. Prior to the anticipated CFP reforms
coming into effect during 2003, these proposed TACs were then
subject to annual horse-trading by the EU Council of Fisheries
Ministers, which is required to take into account economic and
social conditions as well as resource status when agreeing the
The FAO states: "The implications on stock status of considering
increased catches based on these factors remains uncertain but
is of concern
many past decisions on the setting of TACs
(and/or levels of fishing effort) appear inappropriate in light
of the biologically based advice. The pattern of agreed TACs exceeding
advised TACs has contributed, together with the enforcement problems
and stock assessment uncertainties
to the poor long-term
performance of TACs as management measures. In contrast, effective
management of fishing fleets with reduced capacity could provide
many benefits, including increased overall landings and economic
yields, increased profitability and increased stability in catches,
while reducing the risk of stock collapse" (FAO, 1997a).
In 1997 the FAO stated that the large overcapacity of the European
fleet and the poor status of many of the resources have led to
agreed TACs being restrictive for an increasing number of stocks.
"The difficulties inherent in enforcing output based fisheries
regulations such as TACs (rather than input based measures such
as limited entry) and the resulting low probability of detecting
transgressions creates economic conditions that encourage illegal
overfishing. Hence, actual catches exceed restrictive agreed TACs"
(CEC 2001). The European Commission's response was to call for
cuts of up to 40% in the size of certain national fleets to be
included as part of the Fourth Multi-annual Guidance Programme
(MAGP IV), which ran from 1997-2002.
The agreed TAC for a particular
stock may also be exceeded because fish from the stock are taken
as bycatch in fisheries targeting other species.
According to the FAO (1997a):
"Illegal catches are either not reported at all or are reported
as different under-quota species, resulting in a deterioration
in the quality of fisheries statistics used for stock assessments.
This situation is worsening and is a cause for great concern."
The FAO's Advisory Committee on Fisheries Management (ACFM) has
warned that, if data quality continues to deteriorate, it will
become impossible to monitor certain stocks, particularly with
regards to the provision of short-term forecasts used for setting
"The under-reporting of catches, particularly where the level
of under-reporting is unknown and/or fluctuates widely, can result
in the under-estimation of stock size, which, in turn, results
in larger discrepancies between actual and predicted catch rates.
As this discrepancy grows, the incentive for fishers to continue
fishing illegally increases and the degree of under-reporting
of catches increases. This combination of high exploitation intensities
and poor quality data has lead to concerns over the future effectiveness
of TAC-based quota management. For instance, the ACFM suggests
that stand-alone technical measures or catch controls are likely
to be insufficient in reducing fishing mortality on the Irish
Sea cod stock such that spawning stock biomass can return to safe
fish catches and selectivity
Regarding the huge expanse of open ocean that lies to the west
of the European continental shelf (OSPAR Region V Wider Atlantic),
the OSPAR Commission reports that the impacts of overfishing "are
being exacerbated by the general disregard of size restrictions
on the fish that may be landed" (OSPAR 2000).
The Worldwide Fund for Nature
(WWF) recently stated that the capture of significant quantities
of small, immature fish is a general problem, common to many European
fisheries, which threatens the integrity of fish stocks and thus
seriously undermines the sustainability of fisheries (WWF 2002).
"Selectivity" refers to the
variation in the capability of particular types, configurations
and deployment of fishing gear to catch individuals of a given
species, depending on the size of the fish, which in turn depends
on the age. Thus more selective gear or fishing practices result
in a higher percentage of individuals of the targeted size/age
in the catch. By selectively removing fish of a certain age group
from the population instead of removing a proportion of
the overall population that is representative of all age groups
selectivity can result in a significant change in the age
structure of the population compared to the unexploited state.
Fisheries that employ low selectivity
start by targeting small sized fish, which are of course juveniles.
In such cases, the maximum sustainable yield from the fishery
is reached with a rather low intensity of fishing or fishing effort,
so that higher levels of fishing effort translate into reduced
captures as the stock is overexploited. This is known as "growth
overfishing", and is particularly prevalent in fisheries capturing
long-lived species that usually reach sexual maturity late in
life, like hake or cod. Better selectivity (i.e. using gear and
practices that start catching fish at much larger sizes, hence
older) enables long-term, sustainable and efficient production
to be achieved as well as much higher catches, which are obtained
through applying equally higher levels of fishing effort (WWF
Many commercially important
species of fish produce large numbers of eggs. Environmental factors
such as water temperature, which affect the survival of eggs and
larvae, tend to determine how many juvenile fish are recruited
into the population as a result of each annual reproductive episode,
rather than the size of the mature breeding population (spawning
"However, sometimes fishing is so intense that the adult, reproductive
part of the population is pushed below a critical point so that
the size of recruitment becomes dependent on the size of the spawning
stock. This dangerous situation is called recruitment overfishing,
and contrary to the case of growth overfishing (which implies
the reduction in the productivity of the fishery, in the mean
size of the fish and the in the size of the population), it can
cause the complete collapse of the fishery" (WWF 2002).
Although all species are susceptible,
it is small, pelagic species such as sardine or anchovy that are
characterized by a short life span and an early sexual maturity,
that are especially prone to this dangerous type of overfishing.
A typical sequence in many overfished
fisheries would be high/excessive fishing effort using low selectivity,
followed by growth overfishing, recruitment overfishing and, finally,
the collapse of the fishery (WWF 2002).
WWF state that: "Two immediate solutions to avoid any kind of
overfishing are 1) capturing fish at the right sizes (= weights)
so that the overall productivity of the fishery be kept high and
2) maximizing reproduction by allowing fish to spawn at least
once before being caught, all this in the context of a reasonable
level of fishing effort. The problem, however, is not so straightforward
to remedy once overfishing is reached, since profound changes
in the population are inflicted. In this case, improving selectivity
alone is no longer a viable solution if it is not accompanied
by a drastic reduction of fishing capacity that would allow the
population to rebuild and enough fish of the newly targeted size
are available to the fleets" (WWF 2002).
Overexploited, depleted and
recovering fish stocks generally have potential to return to historical
levels of production provided fishing effort is reduced through
often drastic measures, such as capacity reduction,
aimed at reducing or reverting overfishing conditions and bycatch
in other fisheries; and provided that irreversible ecosystem imbalances
(changes in population structure, predator-prey relationships,
etc.) have not taken place.
Overfishing conditions can be
reduced by significantly increasing the age at first capture,
prohibiting the exploitation of juveniles, increasing mesh sizes,
and temporarily or permanently closing areas where adults spawn
and/or juveniles concentrate (i.e. spawning and nursery grounds).
Juvenile cod have been successfully protected in Norway through
ad hoc area closures. Elsewhere, closed seasons in areas
have produced improvements in catch rates.
Effective management of the
Arctic cod stock in the Norwegian and Barents Seas has
in contrast to most other Atlantic cod stocks led to a
recovery in spawning stock biomass from a depleted condition to
a level not seen since the 1950s following a major reduction in
fishing mortality in the late 1980s (FAO 1997a).
There is also a significant
potential for improvement from the reduction of bycatch. The FAO
has estimated that between 18-39 million tonnes (average 27 million
tonnes) of fish are discarded at sea every year (FAO 1997a). This
comprises species of low commercial value but also a large proportion
of juveniles. The benefits resulting from a reduction of unwanted
bycatch through increased survival of juvenile fish can be very
solutions to overfishing
There are no simple or cheap solutions to the problem of overfishing
(FAO 1997b). It is widely recognised that for developed countries,
solutions that include market-based strategies for controlling
fishing effort tend to be more effective than others however
politically uncomfortable it may be for governments to step-up
regulation. "Unfortunately, initial effects of government measures
to reduce overfishing are essentially negative: some unemployed
fishermen, less fish and higher prices. With time, most of these
effects would be reversed: more fish, lower prices and stable,
economically attractive employment" (FAO 1997a).
Outside the fishery sector,
the growing awareness overfishing and other threats facing fisheries,
the resources, and the marine environment in general has led to
a number of initiatives by non-governmental and business organisations.
In particular, the establishment of the Marine
Stewardship Council builds on the assumption that the promotion
of fisheries products certified as coming from sustainably managed
and environmentally sound fisheries and aquaculture can induce
the fishing and aquaculture industries to better manage current
fisheries practices, both locally and globally.
In practice, effective management should allow presently overfished
resources to recover, thereby increasing fisheries production
in the longer-term. The FAO has estimated that better regional
management of marine capture fisheries could yield an additional
10 million tonnes worldwide. "The economic benefits from improved
management could be as spectacular. As effort limitations become
effective, the use of capital and labour will fall (as will annual
costs) more rapidly than will income from the fishery. As stocks
recover, revenues will grow in absolute terms. These effects will
translate into higher disposable income for those fishers who
remain, as well as expanding tax revenues" (FAO 1997b).
In 1995, with this in mind,
the FAO Conference adopted the Code
of Conduct for Responsible Fisheries as guidance for achieving
efficient, sustainable and responsible fisheries.
In the medium- to long-term,
the major challenge facing marine fisheries is improved and responsible
management of stocks. Such management requires the regulation
of production in a precautionary manner so that excessive effort,
leading to overfishing, is not applied to target stocks. In addition,
adoption of an ecosystem approach requires fisheries management
processes to take account of fishing impacts on non-target stocks
and other components of the marine ecosystem.
Please note: This page will be updated during 2006.