Fisheries management
Encyclopedia
Fisheries management draws on fisheries science
in order to find ways to protect fishery
resources so sustainable exploitation is possible. Modern fisheries management is often referred to as a governmental system of appropriate management rules based on defined objectives and a mix of management means to implement the rules, which are put in place by a system of monitoring control and surveillance
.
residents for about 700 years, had prohibitions against taking more than could be eaten and about giving back the first fish caught as an offering to sea god Tangaroa
. Starting in the 18th century attempts were made to regulate fishing in the North Norwegian
fishery. This resulted in the enactment of a law in 1816 on the Lofoten
fishery, which established in some measure what has come to be known as territorial use rights.
Governmental resource protection-based fisheries management is a relatively new idea, first developed for North European fisheries after the first Overfishing
Conference held in London in 1936. In 1957 British fisheries researchers Ray Beverton
and Sidney Holt
published a seminal work on North Sea
commercial fisheries dynamics. In the 1960s the work became the theoretical platform for North European management schemes.
After some years away from the field of fisheries management, Beverton criticized his earlier work in a paper given at the first World Fisheries Congress in Athens in 1992. "The Dynamics of Exploited Fish Populations" expressed his concerns, including the way his and Sydney Holt's work had been misinterpreted and misused by fishery biologists and managers during the previous 30 years. Nevertheless, the institutional foundation for modern fishery management had been laid.
, fisheries management should be based explicitly on political objectives, ideally with transparent priorities. Typical political objectives when exploiting a fish resource are to:
Such political goals can also be a weak part of fisheries management, since the objectives can conflict with each other.
session in 1995. The precautionary approach
it prescribes is typically implemented in concrete management rules as minimum spawning
biomass
, maximum fishing mortality rates, etc. In 2005 the Fisheries Centre
at the University of British Columbia
comprehensively reviewed the performance of the world's major fishing nations against the Code.
International agreements are required in order to regulate fisheries in international waters. The desire for agreement on this and other maritime issues led to three conferences on the Law of the Sea, and ultimately to the treaty known as the United Nations Convention on the Law of the Sea
(UNCLOS). Concepts such as exclusive economic zone
s (EEZ, extending 200 nautical miles (370.4 km) from a nation's coasts) allocate certain sovereign rights and responsibilities for resource management to individual countries.
Other situations need additional intergovernmental coordination. For example, in the Mediterranean Sea and other relatively narrow bodies of water, EEZ of 200 nautical miles (370.4 km) are irrelevant. International waters beyond 12 nautical miles (22.2 km) from shore require explicit agreements.
Straddling fish stocks, which migrate
through more than one EEZ also present challenges. Here sovereign responsibility must be agreed with neighbouring coastal states and fishing entities. Usually this is done through the medium of a regional organisation set up for the purpose of coordinating the management
of that stock.
UNCLOS does not prescribe precisely how fisheries confined only to international waters should be managed. Several new fisheries (such as high seas bottom trawling
fisheries) are not (yet) subject to international agreement across their entire range. In November 2004 the UN General Assembly issued a resolution on Fisheries that prepared for further development of international fisheries management law.
" or similar, controlling aspects of fisheries within their exclusive economic zones.
Four categories of management means have been devised, regulating either input/investment, or output, and operating either directly or indirectly:
Technical means may include:
A large scale study in 2008 provided strong evidence that ITQ's can help to prevent fishery collapse and even restore fisheries that appear to be in decline.
of the United Nations, advises that the precautionary approach or principle should be applied when "ecosystem resilience and human impact (including reversibility) are difficult to forecast and hard to distinguish from natural changes." The precautionary principle
suggests that when an action risks harm, it should not be proceeded with until it can be scientifically proven to be safe. Historically fishery managers have applied this principle the other way round; fishing activities have not been curtailed until it has been proven that they have already damaged existing ecosystems. In a paper published in 2007, Shertzer and Prager suggested that there can be significant benefits to stock biomass
and fishery yield if management is stricter and more prompt.
describes the growth and decline of a given fishery stock
over time, as controlled by birth, death and migration. It is the basis for understanding changing fishery patterns and issues such as habitat destruction, predation and optimal harvesting rates. The population dynamics of fisheries has been traditionally used by fisheries scientist
s to determine sustainable yields
.
The basic accounting relation for population dynamics is the BIDE
model:
where N1 is the number of individuals at time 1, N0 is the number of individuals at time 0, B is the number of individuals born, D the number that died, I the number that immigrated, and E the number that emigrated between time 0 and time 1. While immigration and emigration can be present in wild fisheries
, they are usually not measured.
Care is needed when applying population dynamics to real world fisheries. In the past, over-simplistic modelling, such as ignoring the size, age and reproductive status of the fish, focusing solely on a single species, ignoring bycatch
and physical damage
to the ecosystem, has accelerated the collapse of key stocks
.
points to pollution and global warming as the causes of unprecedentedly low fish stocks in recent years, writing, "Everybody would like to see the rebuilding of fish stocks and this can only be achieved if we understand all of the influences, human and natural, on fish dynamics." Overfishing
has also had an effect. Frid adds, “Fish communities can be altered in a number of ways, for example they can decrease if particular sized individuals of a species are targeted, as this affects predator and prey dynamics. Fishing, however, is not the sole perpetrator of changes to marine life - pollution
is another example [...] No one factor operates in isolation and components of the ecosystem respond differently to each individual factor."
In contrast to the traditional approach of focusing on a single species, the ecosystem-based approach
is organized in terms of ecosystem services
. Ecosystem-based fishery concepts have been implemented in some regions. In 2007 a group of scientists offered the following ten commandments
Traditional management practices aim to reduce the number of old, slow-growing fish, leaving more room and resources for younger, faster-growing fish. Most marine fish produce huge numbers of eggs. The assumption was that younger spawners would produce plenty of viable larvae
.
However, 2005 research on rockfish
shows that large, elderly females are far more important than younger fish in maintaining productive fisheries. The larvae produced by these older maternal fish grow faster, survive starvation better, and are much more likely to survive than the offspring of younger fish. Failure to account for the role of older fish may help explain recent collapses of some major US West Coast fisheries. Recovery of some stocks is expected to take decades. One way to prevent such collapses is to establish marine reserves, where fishing is not allowed and fish populations age naturally.
The most reliable source for summary statistics is the FAO
Fisheries Department.
, with Ecosim
(EwE), is an ecosystem
modelling software suite
. It was initially a NOAA initiative led by Jeffrey Polovina, later primarily developed at the Fisheries Centre
of the University of British Columbia
. In 2007, it was named as one of the ten biggest scientific breakthroughs in NOAA’s 200-year history. The citation states that Ecopath "revolutionized scientists’ ability worldwide to understand complex marine ecosystems". Behind this lies two decades of development work by Villy Christensen
, Carl Walters
, Daniel Pauly
, and other fisheries scientists. As of 2010 there are 6000 registered users in 155 countries. Ecopath is widely used in fisheries management as a tool for modelling and visualising the complex relationships that exist in real world marine ecosystems.
Management regulations must also consider the implications for stakeholders. Commercial fishermen rely on catches to provide for their families just as farmers rely on crops. Commercial fishing can be a traditional trade passed down from generation to generation. Most commercial fishing is based in towns built around the fishing industry; regulation changes can impact an entire town’s economy. Cuts in harvest quotas can have adverse affects on the ability of fishermen to compete with the tourism industry.
of global fish stock
s has been allowed to run down. This biomass is now diminished to the point where it is no longer possible to sustainably
catch the amount of fish that could be caught. According to a 2008 UN report, titled The Sunken Billions: The Economic Justification for Fisheries Reform
, the world's fishing fleet
s incur a "$US 50 billion annual economic loss" through depleted stocks and poor fisheries management. The report, produced jointly by the World Bank
and the UN Food and Agriculture Organization
(FAO), asserts that half the world's fishing fleet
could be scrapped with no change in catch.
Fisheries science
Fisheries science is the academic discipline of managing and understanding fisheries. It is a multidisciplinary science, which draws on the disciplines of oceanography, marine biology, marine conservation, ecology, population dynamics, economics and management to attempt to provide an integrated...
in order to find ways to protect fishery
Fishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
resources so sustainable exploitation is possible. Modern fisheries management is often referred to as a governmental system of appropriate management rules based on defined objectives and a mix of management means to implement the rules, which are put in place by a system of monitoring control and surveillance
Monitoring control and surveillance
Monitoring, control and surveillance , in the context of fisheries, is defined by the Food and Agriculture Organization of the United Nations as a broadening of traditional enforcing national rules over fishing, to the support of the broader problem of fisheries management.Internationally, the...
.
History
Fisheries have been explicitly managed in some places for hundreds of years. For example, the Māori people, New ZealandNew Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
residents for about 700 years, had prohibitions against taking more than could be eaten and about giving back the first fish caught as an offering to sea god Tangaroa
Tangaroa
In Māori mythology, Tangaroa is one of the great gods, the god of the sea. He is a son of Ranginui and Papatuanuku, Sky and Earth. After he joins his brothers Rongo, Tūmatauenga, Haumia, and Tane in the forcible separation of their parents, he is attacked by his brother Tawhirimatea, the god of...
. Starting in the 18th century attempts were made to regulate fishing in the North Norwegian
Nord-Norge
North Norway or Nord-Noreg , North Sámi: Davvi-Norga) is the geographical region of northern Norway, consisting of the three counties Nordland, Troms and Finnmark, in total about 35% of the Norwegian mainland. Some of the largest towns in North Norway are Mo i Rana, Bodø, Narvik, Harstad, Tromsø...
fishery. This resulted in the enactment of a law in 1816 on the Lofoten
Lofoten
Lofoten is an archipelago and a traditional district in the county of Nordland, Norway. Though lying within the Arctic Circle, the archipelago experiences one of the world's largest elevated temperature anomalies relative to its high latitude.-Etymology:...
fishery, which established in some measure what has come to be known as territorial use rights.
"The fishing banks were divided into areas belonging to the nearest fishing base on land and further subdivided into fields where the boats were allowed to fish. The allocation of the fishing fields was in the hands of local governing committees, usually headed by the owner of the onshore facilities which the fishermen had to rent for accommodation and for drying the fish."
Governmental resource protection-based fisheries management is a relatively new idea, first developed for North European fisheries after the first Overfishing
Overfishing
Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans....
Conference held in London in 1936. In 1957 British fisheries researchers Ray Beverton
Ray Beverton
Raymond John Heaphy Beverton, CBE, FRS was an important founder of fisheries science. He is best known for the book On the Dynamics of Exploited Fish Populations which he wrote with Sidney Holt. The book is a cornerstone of modern fisheries science and remains much used today...
and Sidney Holt
Sidney Holt
Sidney J. Holt is an important founder of fisheries science. He is best known for the book On the Dynamics of Exploited Fish Populations which he published with Ray Beverton in 1957. The book is a cornerstone of modern fisheries science and remains much used today. Holt served with the FAO in 1953...
published a seminal work on North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
commercial fisheries dynamics. In the 1960s the work became the theoretical platform for North European management schemes.
After some years away from the field of fisheries management, Beverton criticized his earlier work in a paper given at the first World Fisheries Congress in Athens in 1992. "The Dynamics of Exploited Fish Populations" expressed his concerns, including the way his and Sydney Holt's work had been misinterpreted and misused by fishery biologists and managers during the previous 30 years. Nevertheless, the institutional foundation for modern fishery management had been laid.
Political objectives
According to the FAOFão
Fão is a town in Esposende Municipality in Portugal....
, fisheries management should be based explicitly on political objectives, ideally with transparent priorities. Typical political objectives when exploiting a fish resource are to:
- maximize sustainable biomass yieldMaximum sustainable yieldIn population ecology and economics, maximum sustainable yield or MSY is, theoretically, the largest yield that can be taken from a species' stock over an indefinite period...
- maximize sustainable economic yieldOptimum sustainable yieldIn population ecology and economics, optimum sustainable yield is the level of effort that maximizes the difference between total revenue and total cost. Or, where marginal revenue equals marginal cost. This level of effort maximizes the economic profit, or rent, of the resource being utilized...
- secure and increase employment
- secure protein production and food supplies
- increase export income
Such political goals can also be a weak part of fisheries management, since the objectives can conflict with each other.
International objectives
Fisheries objectives need to be expressed in concrete management rules. In most countries fisheries management rules should be based on the internationally agreed, though non-binding, Code of Conduct for Responsible Fisheries, agreed at a meeting of the U.N.'s Food and Agriculture Organization FAOFão
Fão is a town in Esposende Municipality in Portugal....
session in 1995. The precautionary approach
Precautionary principle
The precautionary principle or precautionary approach states that if an action or policy has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those...
it prescribes is typically implemented in concrete management rules as minimum spawning
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
biomass
Biomass (ecology)
Biomass, in ecology, is the mass of living biological organisms in a given area or ecosystem at a given time. Biomass can refer to species biomass, which is the mass of one or more species, or to community biomass, which is the mass of all species in the community. It can include microorganisms,...
, maximum fishing mortality rates, etc. In 2005 the Fisheries Centre
Fisheries Centre
The Fisheries Centre, located at the University of British Columbia, promotes multidisciplinary study of aquatic ecosystems and broad-based collaboration with maritime communities, government, NGOs and other partners...
at the University of British Columbia
University of British Columbia
The University of British Columbia is a public research university. UBC’s two main campuses are situated in Vancouver and in Kelowna in the Okanagan Valley...
comprehensively reviewed the performance of the world's major fishing nations against the Code.
International agreements are required in order to regulate fisheries in international waters. The desire for agreement on this and other maritime issues led to three conferences on the Law of the Sea, and ultimately to the treaty known as the United Nations Convention on the Law of the Sea
United Nations Convention on the Law of the Sea
The United Nations Convention on the Law of the Sea , also called the Law of the Sea Convention or the Law of the Sea treaty, is the international agreement that resulted from the third United Nations Conference on the Law of the Sea , which took place from 1973 through 1982...
(UNCLOS). Concepts such as exclusive economic zone
Exclusive Economic Zone
Under the law of the sea, an exclusive economic zone is a seazone over which a state has special rights over the exploration and use of marine resources, including production of energy from water and wind. It stretches from the seaward edge of the state's territorial sea out to 200 nautical...
s (EEZ, extending 200 nautical miles (370.4 km) from a nation's coasts) allocate certain sovereign rights and responsibilities for resource management to individual countries.
Other situations need additional intergovernmental coordination. For example, in the Mediterranean Sea and other relatively narrow bodies of water, EEZ of 200 nautical miles (370.4 km) are irrelevant. International waters beyond 12 nautical miles (22.2 km) from shore require explicit agreements.
Straddling fish stocks, which migrate
Fish migration
Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousands of kilometres...
through more than one EEZ also present challenges. Here sovereign responsibility must be agreed with neighbouring coastal states and fishing entities. Usually this is done through the medium of a regional organisation set up for the purpose of coordinating the management
Straddling Fish Stocks Agreement
The Straddling Fish Stocks Agreement was created by the United Nations to enhance the cooperative management of fisheries resources that span wide areas, and are of economic and environmental concern to a number of nations.The full name of the agreement is:...
of that stock.
UNCLOS does not prescribe precisely how fisheries confined only to international waters should be managed. Several new fisheries (such as high seas bottom trawling
Bottom trawling
Bottom trawling is trawling along the sea floor. It is also often referred to as "dragging".The scientific community divides bottom trawling into benthic trawling and demersal trawling...
fisheries) are not (yet) subject to international agreement across their entire range. In November 2004 the UN General Assembly issued a resolution on Fisheries that prepared for further development of international fisheries management law.
Management mechanisms
Many countries have set up Ministries/Government Departments, named "Ministry of FisheriesMinistry of Fisheries (New Zealand)
The Ministry of Fisheries , also known by its acronym MFish, is a state sector organisation of New Zealand whose role is ensuring the sustainable utilisation of fisheries. This involves conserving, using, enhancing and developing New Zealand's fisheries resources. New Zealand's Minister of...
" or similar, controlling aspects of fisheries within their exclusive economic zones.
Four categories of management means have been devised, regulating either input/investment, or output, and operating either directly or indirectly:
| Inputs | Outputs | |
|---|---|---|
| Indirect | Vessel licensing | Catching techniques |
| Direct | Limited entry | Catch quota and technical regulation |
Technical means may include:
- prohibiting devices such as bows and arrows, and spears, or firearms
- prohibiting nets
- setting minimum mesh sizes
- limiting the average potential catch of a vessel in the fleet (vessel and crew size, gear, electronic gear and other physical "inputs".
- prohibiting bait
- snagging
- limits on fish traps
- limiting the number of poles or lines per fisherman
- restricting the number of simultaneous fishing vessels
- limiting a vessel's average operational intensity per unit time at sea
- limiting average time at sea
Catch quotas
Systems that use individual transferable quotas (ITQ), also called individual fishing quota limit the total catch and allocate shares of that quota among the fishers who work that fishery. Fishers can buy/sell/trade shares as they choose.A large scale study in 2008 provided strong evidence that ITQ's can help to prevent fishery collapse and even restore fisheries that appear to be in decline.
Precautionary principle
The Fishery Manager's Guidebook issued in 2009 by the FAOFão
Fão is a town in Esposende Municipality in Portugal....
of the United Nations, advises that the precautionary approach or principle should be applied when "ecosystem resilience and human impact (including reversibility) are difficult to forecast and hard to distinguish from natural changes." The precautionary principle
Precautionary principle
The precautionary principle or precautionary approach states that if an action or policy has a suspected risk of causing harm to the public or to the environment, in the absence of scientific consensus that the action or policy is harmful, the burden of proof that it is not harmful falls on those...
suggests that when an action risks harm, it should not be proceeded with until it can be scientifically proven to be safe. Historically fishery managers have applied this principle the other way round; fishing activities have not been curtailed until it has been proven that they have already damaged existing ecosystems. In a paper published in 2007, Shertzer and Prager suggested that there can be significant benefits to stock biomass
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
and fishery yield if management is stricter and more prompt.
Population dynamics
Population dynamicsPopulation dynamics of fisheries
A fishery is an area with an associated fish or aquatic population which is harvested for its commercial or recreational value. Fisheries can be wild or farmed. Population dynamics describes the ways in which a given population grows and shrinks over time, as controlled by birth, death, and...
describes the growth and decline of a given fishery stock
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
over time, as controlled by birth, death and migration. It is the basis for understanding changing fishery patterns and issues such as habitat destruction, predation and optimal harvesting rates. The population dynamics of fisheries has been traditionally used by fisheries scientist
Fisheries science
Fisheries science is the academic discipline of managing and understanding fisheries. It is a multidisciplinary science, which draws on the disciplines of oceanography, marine biology, marine conservation, ecology, population dynamics, economics and management to attempt to provide an integrated...
s to determine sustainable yields
Sustainable yield in fisheries
The sustainable yield of natural capital is the ecological yield that can be extracted without reducing the base of capital itself, i.e. the surplus required to maintain ecosystem services at the same or increasing level over time. This yield usually varies over time with the needs of the...
.
The basic accounting relation for population dynamics is the BIDE
Matrix population models
Population models are used in population ecology to model the dynamics of wildlife or human populations. Matrix population models are a specific type of population model that uses matrix algebra...
model:
- N1 = N0 + B − D + I − E
where N1 is the number of individuals at time 1, N0 is the number of individuals at time 0, B is the number of individuals born, D the number that died, I the number that immigrated, and E the number that emigrated between time 0 and time 1. While immigration and emigration can be present in wild fisheries
Wild fisheries of the world
A fishery is an area with an associated fish or aquatic population which is harvested for its commercial value. Fisheries can be marine or freshwater. They can also be wild or farmed. This article is an overview of the habitats occupied by the worlds' wild fisheries, and the human impacts on those...
, they are usually not measured.
Care is needed when applying population dynamics to real world fisheries. In the past, over-simplistic modelling, such as ignoring the size, age and reproductive status of the fish, focusing solely on a single species, ignoring bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
and physical damage
Environmental effects of fishing
The environmental impact of fishing can be divided into issues that involve the availability of fish to be caught, such as overfishing, sustainable fisheries, and fisheries management; and issues that involve the impact of fishing on other elements of the environment, such as by-catch.These...
to the ecosystem, has accelerated the collapse of key stocks
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
.
Ecosystem based fisheries
According to marine ecologist Chris Frid, the fishing industryFishing industry
The fishing industry includes any industry or activity concerned with taking, culturing, processing, preserving, storing, transporting, marketing or selling fish or fish products....
points to pollution and global warming as the causes of unprecedentedly low fish stocks in recent years, writing, "Everybody would like to see the rebuilding of fish stocks and this can only be achieved if we understand all of the influences, human and natural, on fish dynamics." Overfishing
Overfishing
Overfishing occurs when fishing activities reduce fish stocks below an acceptable level. This can occur in any body of water from a pond to the oceans....
has also had an effect. Frid adds, “Fish communities can be altered in a number of ways, for example they can decrease if particular sized individuals of a species are targeted, as this affects predator and prey dynamics. Fishing, however, is not the sole perpetrator of changes to marine life - pollution
Marine pollution
Marine pollution occurs when harmful, or potentially harmful effects, can result from the entry into the ocean of chemicals, particles, industrial, agricultural and residential waste, noise, or the spread of invasive organisms. Most sources of marine pollution are land based...
is another example [...] No one factor operates in isolation and components of the ecosystem respond differently to each individual factor."
In contrast to the traditional approach of focusing on a single species, the ecosystem-based approach
Ecosystem Approach
The Ecosystem Approach is considered one of the most important principles of sustainable environmental management.The Fifth Conference of the Parties to the Convention on Biological Diversity defined the Ecosystem Approach in Decision V/6, Annex A, section 1 as ‘a strategy for the integrated...
is organized in terms of ecosystem services
Ecosystem services
Humankind benefits from a multitude of resources and processes that are supplied by natural ecosystems. Collectively, these benefits are known as ecosystem services and include products like clean drinking water and processes such as the decomposition of wastes...
. Ecosystem-based fishery concepts have been implemented in some regions. In 2007 a group of scientists offered the following ten commandments
- Report to Congress (2009): The State of Science to Support an Ecosystem Approach to Regional Fishery Management National Marine Fisheries Service, NOAA Technical Memorandum NMFS-F/SPO-96.
Elderly maternal fish
Larvae
In Roman mythology, lemures were shades or spirits of the restless or malignant dead, and are probably cognate with an extended sense of larvae as disturbing or frightening...
.
However, 2005 research on rockfish
Sebastes
Sebastes is a genus of fish in the family Sebastidae , most of which have the common name of rockfish. Most of the world's almost 110 Sebastes species live in the north Pacific, although two live in the south Pacific/Atlantic and four Sebastes is a genus of fish in the family Sebastidae (though...
shows that large, elderly females are far more important than younger fish in maintaining productive fisheries. The larvae produced by these older maternal fish grow faster, survive starvation better, and are much more likely to survive than the offspring of younger fish. Failure to account for the role of older fish may help explain recent collapses of some major US West Coast fisheries. Recovery of some stocks is expected to take decades. One way to prevent such collapses is to establish marine reserves, where fishing is not allowed and fish populations age naturally.
Data quality
According to fisheries scientist Milo Adkison, the primary limitation in fisheries management decisions is the absence of quality data. Fisheries management decisions are often based on population models, but the models need quality data to be effective. He asserts that scientists and fishery managers would be better served with simpler models and improved data.The most reliable source for summary statistics is the FAO
Fão
Fão is a town in Esposende Municipality in Portugal....
Fisheries Department.
Ecopath
EcopathEcopath
Ecopath with Ecosim is a free ecosystem modelling software suite. It was initially a NOAA initiative led by Jeffrey Polovina, but since primarily developed at the Fisheries Centre of the University of British Columbia. In 2007, it was named as one of the ten biggest scientific breakthroughs in...
, with Ecosim
Ecosim
EcosimPro is a simulation tool developed by Empresarios Agrupados A.I.E for modelling simple and complex physical processes that can be expressed in terms of Differential algebraic equations or Ordinary differential equations and Discrete event simulation....
(EwE), is an ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
modelling software suite
Software suite
A software suite or application suite is a collection of computer programs, usually application software and programming software of related functionality, often sharing a more-or-less common user interface and some ability to smoothly exchange data with each other.Sometimes software makers...
. It was initially a NOAA initiative led by Jeffrey Polovina, later primarily developed at the Fisheries Centre
Fisheries Centre
The Fisheries Centre, located at the University of British Columbia, promotes multidisciplinary study of aquatic ecosystems and broad-based collaboration with maritime communities, government, NGOs and other partners...
of the University of British Columbia
University of British Columbia
The University of British Columbia is a public research university. UBC’s two main campuses are situated in Vancouver and in Kelowna in the Okanagan Valley...
. In 2007, it was named as one of the ten biggest scientific breakthroughs in NOAA’s 200-year history. The citation states that Ecopath "revolutionized scientists’ ability worldwide to understand complex marine ecosystems". Behind this lies two decades of development work by Villy Christensen
Villy Christensen
Villy Christensen is an ecosystem modeller with a background in fisheries science. He is known for his work as a project leader and core developer of Ecopath, an ecosystem modelling software system widely used in fisheries management. Ecopath was initially an initiative of the NOAA, but since...
, Carl Walters
Carl Walters
Carl Walters is an American born biologist known for his work involving fisheries stock assessments, the adaptive management concept, and ecosystem modeling. Walters has been a professor of Zoology and Fisheries at the University of British Columbia since 1969...
, Daniel Pauly
Daniel Pauly
Daniel Pauly is a French-born marine biologist, well-known for his work in studying human impacts on global fisheries. He is a professor and the project leader of the Sea Around Us Project at the Fisheries Centre at the University of British Columbia. He also served as Director of the Fisheries...
, and other fisheries scientists. As of 2010 there are 6000 registered users in 155 countries. Ecopath is widely used in fisheries management as a tool for modelling and visualising the complex relationships that exist in real world marine ecosystems.
Human factors
Managing fisheries is about managing people and businesses, and not about managing fish. Fish populations are managed by regulating the actions of people. If fisheries management is to be successful, then associated human factors, such as the reactions of fishermen, are of key importance, and need to be understood.Management regulations must also consider the implications for stakeholders. Commercial fishermen rely on catches to provide for their families just as farmers rely on crops. Commercial fishing can be a traditional trade passed down from generation to generation. Most commercial fishing is based in towns built around the fishing industry; regulation changes can impact an entire town’s economy. Cuts in harvest quotas can have adverse affects on the ability of fishermen to compete with the tourism industry.
Performance
The biomassBiomass (ecology)
Biomass, in ecology, is the mass of living biological organisms in a given area or ecosystem at a given time. Biomass can refer to species biomass, which is the mass of one or more species, or to community biomass, which is the mass of all species in the community. It can include microorganisms,...
of global fish stock
Fish stock
Fish stocks are subpopulations of a particular species of fish, for which intrinsic parameters are the only significant factors in determining population dynamics, while extrinsic factors are considered to be insignificant.-The stock concept:All species have geographic limits to their...
s has been allowed to run down. This biomass is now diminished to the point where it is no longer possible to sustainably
Maximum sustainable yield
In population ecology and economics, maximum sustainable yield or MSY is, theoretically, the largest yield that can be taken from a species' stock over an indefinite period...
catch the amount of fish that could be caught. According to a 2008 UN report, titled The Sunken Billions: The Economic Justification for Fisheries Reform
The Sunken Billions
The Sunken Billions is a study jointly published in 2008 by the World Bank and by the Food and Agriculture Organization of the United Nations...
, the world's fishing fleet
Fishing fleet
A fishing fleet is an aggregate of commercial fishing vessels. The term may be used of all vessels operating out of a particular port, all vessels engaged in a particular type of fishing , or all fishing vessels of a country or region.Although fishing vessels are not formally organized as if they...
s incur a "$US 50 billion annual economic loss" through depleted stocks and poor fisheries management. The report, produced jointly by the World Bank
World Bank
The World Bank is an international financial institution that provides loans to developing countries for capital programmes.The World Bank's official goal is the reduction of poverty...
and the UN Food and Agriculture Organization
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations is a specialised agency of the United Nations that leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and...
(FAO), asserts that half the world's fishing fleet
Fishing fleet
A fishing fleet is an aggregate of commercial fishing vessels. The term may be used of all vessels operating out of a particular port, all vessels engaged in a particular type of fishing , or all fishing vessels of a country or region.Although fishing vessels are not formally organized as if they...
could be scrapped with no change in catch.
"By improving governance of marine fisheries, society could capture a substantial part of this $50 billion annual economic loss. Through comprehensive reform, the fisheries sector could become a basis for economic growth and the creation of alternative livelihoods in many countries. At the same time, a nation’s natural capital in the form of fish stocks could be greatly increased and the negative impacts of the fisheries on the marine environment reduced."
See also
- Age class structureAge class structureAge class structure in fisheries and wildlife management is a part of population assessment. Age can be determined by counting growth rings in fish scales, otoliths, cross-sections of fin spines for species with thick spines such as triggerfish, or teeth for a few species. Each method has its...
- Beverton–Holt model
- Community supported fisheryCommunity supported fisheryA community supported fishery is a shore-side community of people collaborating with the local fishing community. Tailored after the community supported agriculture model, a CSF contributes freshly caught local seafood to the local markets while providing fishermen with a better price on less catch...
- Marine conservationMarine conservationMarine conservation, also known as marine resources conservation, is the protection and preservation of ecosystems in oceans and seas. Marine conservation focuses on limiting human-caused damage to marine ecosystems, and on restoring damaged marine ecosystems...
- Marine Protected AreaMarine Protected AreaMarine Protected Areas, like any protected area, are regions in which human activity has been placed under some restrictions in the interest of conserving the natural environment, it's surrounding waters and the occupant ecosystems, and any cultural or historical resources that may require...
- Maximum sustainable yieldMaximum sustainable yieldIn population ecology and economics, maximum sustainable yield or MSY is, theoretically, the largest yield that can be taken from a species' stock over an indefinite period...
- Regional Fisheries Management OrganisationRegional Fisheries Management OrganisationA Regional Fisheries Management Organisation , sometimes called regional fisheries organisation , is an international organisation dedicated to the sustainable management of fishery resources in a particular region of international waters, or of highly migratory species.RFMOs may focus on certain...
- Sustainable fisheriesSustainable fisheriesSustainability in fisheries combines theoretical disciplines, such as the population dynamics of fisheries, with practical strategies, such as avoiding overfishing through techniques such as individual fishing quotas, curtailing destructive and illegal fishing practices by lobbying for appropriate...
- The Sunken BillionsThe Sunken BillionsThe Sunken Billions is a study jointly published in 2008 by the World Bank and by the Food and Agriculture Organization of the United Nations...
- The End of the LineThe End of the Line: How Overfishing Is Changing the World and What We EatThe End of The Line: How Overfishing Is Changing the World And What We Eat is a book by journalist Charles Clover about overfishing. Clover, an environment editor of the Daily Telegraph , describes how modern fishing is destroying ocean ecosystems. He concludes that current worldwide fish...
(Documentary)
External links
- Special Issue: Toward Darwinian fisheries management
- Managing Marine Fisheries - Smithsonian Ocean Portal
- The Sea Ahead... learning from the past. A web site of the Peter Wall Institute for Advanced StudiesPeter Wall Institute for Advanced StudiesFounded in 1991, the Peter Wall Institute for Advanced Studies is the senior research institute at the University of British Columbia. It supports basic research through collaborative, interdisciplinary initiatives...
promoting ecosystem-based fisheries management. - founded by a practitioner - Key concepts in Fisheries Management The Fisheries Secretariat. Published 6 June 2005.
- NZ Fisheries Planning Site - An online community being built to support a collaborative approach to fisheries management
- FAO: Fisheries and Aquaculture Department. State of the World Fisheries and Aquaculture 2008. Retrieved 6 April 2009
- Social & Economic Benefits of Fisheries Management from "NOAA Socioeconomics" website initiative
- UN: Oceans and the Law of the SeaLaw of the seaLaw of the sea may refer to:* United Nations Convention on the Law of the Sea* Admiralty law* The Custom of the Sea...
: General Assembly resolutions and decisions - Conservation Science Institute
- Can 'Catch Shares' Reverse Fisheries Collapse? – YouTube
- How to Save New England's Fishing Villages – ReasonOnline