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. According to the FAO, there are "no clear and generally accepted definitions of fisheries management". However, the working definition used by the FAO and much cited elsewhere is:
- The integrated process of information gathering, analysis, planning, consultation, decision-making, allocation of resources and formulation and implementation, with enforcement as necessary, of regulations or rules which govern fisheries activities in order to ensure the continued productivity of the resources and the accomplishment of other fisheries objectives.
Fisheries have been explicitly managed in some places for hundreds of years. For example, the Māori people, New Zealand 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.
"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 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.
Political objectives 
According to the FAO, 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 yield
- maximize sustainable economic yield
- 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 FAO 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 zones (EEZ, extending 200 nautical miles (370 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 km) are irrelevant. International waters beyond 12-nautical-mile (22 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.
Management mechanisms 
Many countries have set up Ministries/Government Departments, named "Ministry of Fisheries" 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:
|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
- 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.
Precautionary principle 
The Fishery Manager's Guidebook issued in 2009 by the FAO 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.":130 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.
Climate change 
In the past, changing climate has affected inland and offshore fisheries and such changes are likely to continue. From a fisheries perspective, the specific driving factors of climate change include rising water temperature, alterations in the hydrologic cycle, changes in nutrient fluxes, and relocation of spawning and nursery habitat. Further, changes in such factors would affect resources at all levels of biological organization, including the genetic, organism, population, and ecosystem levels.
Population dynamics 
Population dynamics 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 scientists to determine sustainable yields.
- 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, 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.
Ecosystem based fisheries 
|“||We propose that rebuilding ecosystems, and not sustainability per se, should be the goal of fishery management. Sustainability is a deceptive goal because human harvesting of fish leads to a progressive simplification of ecosystems in favour of smaller, high turnover, lower trophic level fish species that are adapted to withstand disturbance and habitat degradation.||”|
According to marine ecologist Chris Frid, the fishing industry 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
- 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 
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.
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.
Ecopath, 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.
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 effects on the ability of fishermen to compete with the tourism industry.
The biomass of global fish stocks 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 fleets 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.
"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."
The most prominent failure of fisheries management in recent times has perhaps been the events that lead to the collapse of the northern cod fisheries. More recently, the International Consortium of Investigative Journalists produced a series of journalistic investigations called Looting the seas. These detail investigations into the black market for bluefin tuna, the subsidies propping up the Spanish fishing industry, and the overfishing of the Chilean jack mackerel.
See also 
- Age class structure
- Beverton–Holt model
- Community supported fishery
- Illegal, unreported and unregulated fishing
- Marine conservation
- Marine Protected Area
- Maximum sustainable yield
- Regional Fisheries Management Organisation
- Sustainable fisheries
- The Sunken Billions
- The End of the Line (Documentary)
- FAO (1997) Fisheries Management Section 1.2, Technical Guidelines for Responsible Fisheries. FAO, Rome. ISBN 92-5-103962-3
- Meredith P (2009) Te hī ika – Māori fishing - Traditional practices Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009. Retrieved 22 February 2011.
- Christy FT (1983) Territorial Use Rights in Fisheries: Definitions and Conditions FAO Fisheries, Technical Paper No. 227, Rome. ISBN 92-101269-5.
- Hannesson R, Salvanes JG and Squires A (2008) "Technological change and the Tragedy of the Commons: The Lofoten Fishery over Hundred and Thirty Years" Institutt for Samfunnsøkonomi. Discussion paper SAM 5 2008.
- Beverton & Holt 1957
- Beverton 1992
- FAO, Rome (2009) A Fishery Manager's Guidebook Eds. Cochrane KL and Garcia S. ISBN 978-1-4051-7085-7
- Duzgunes, E; Erdogan, N (2008). "Fisheries Management in the Black Sea Countries" (PDF). Turkish Journal of Fisheries and Aquatic Sciences 8: 181–192.
- Code of Conduct for Responsible Fisheries
- Pitcher, Kalikoski & Pramod 2006
- Sustainable Fishery system, Charles, A. (ed) (2001). Oxford: Blackwell science. p. 95.
- Costello, Christopher; Gaines, Steven D.; Lynham, John (2008). "Can Catch Shares Prevent Fisheries Collapse?".
- Debora MacKenzie New Scientist: Guaranteed fish quotas halt commercial free-for-all
- A Rising Tide: Scientists find proof that privatising fishing stocks can avert a disaster The Economist, 18th Sept, 2008.
- New study offers solution to global fisheries collapse Eureka alert.
- FAO (2003)Fisheries management: The ecosystem approach to fisheries Annex 2. Principles of relevance to an ecosystem approach to fisheries (EAF)], Page 85. Rome. ISBN 92-5-104897-5.
- Dayton PK (1998) "Reversal of the burden of proof in fisheries management" Science, 279(5352): 821– 822.
- Shertzer KW and Prager MH (2007) "Delay in fishery management: diminished yield, longer rebuilding, and increased probability of stock collapse" ICES J. Mar. Sci. 64: 149–159.
- Gucinski, Lackey, and Spence (1990)
- Hlohowskyj, Brody, and Lackey, (1996)
- Wilderbuera, Thomas K and Zhang, Chang Ik (1999) Evaluation of the population dynamics and yield characteristics of Alaska plaice, Pleuronectes quadrituberculatus, in the eastern Bering Sea. Fisheries Research. Volume 41, Issue 2.
- Richard W Zabel, Chris J Harvey, Steven L Katz, Thomas P Good, Phillip S Levin (2003) Ecologically Sustainable Yield. American Scientist, March–April.
- A Sustainable Fishing Simulation Using Mathematical Modeling
- Caswell, H. 2001. Matrix population models: Construction, analysis and interpretation, 2nd Edition. Sinauer Associates, Sunderland, Massachusetts. ISBN 0-87893-096-5.
- Larkin, PA (1977). "An epitaph for the concept of maximum sustained yield". Transactions of the American Fisheries Society 106: 1–11. doi:10.1577/1548-8659(1977)106<1:AEFTCO>2.0.CO;2.
- Walters, C; Maguire, J (1996). "Lessons for stock assessment from the northern cod collapse". Reviews in Fish Biology and Fisheries 6: 125–137.
- Pitcher TJ and Pauly D (1998) "Rebuilding ecosystems, not sustainability, as the proper goal of fishery management" Pages 311-325 in T Pitcher, D Pauly and P Hart, Reinventing Fisheries Management, Chapman & Hall.
- University of Liverpool (2006). "Marine Ecologists To Help Rebuild Decreasing Fish Stocks" ScienceDaily.
- FAO: Fisheries governance: The ecosystem approach to fisheries management Rome. Updated 27 May 2005. Accessed 27 November 2009.
- Francis RC, Hixon MA, Clarke ME, Murawski SA, and Ralston S (2007) Ten commandments for ecosystem-based fisheries scientists Proceedings of Coastal Zone 07, Portland, Oregon. Download
- AAAS (2005) New Science Sheds Light on Rebuilding Fisheries
- "Adkison advocates increased fisheries data gathering". University of Alaska Fairbanks. 2007.
- Fishery statistics: Reliability and policy implications
- Mahon & McConney 2004
- Hilborn, R (2007). "Managing fisheries is managing people: what has been learned?". Fish and Fisheries 8 (4): 285–296. doi:10.1111/j.1467-2979.2007.00263_2.x.
- Elder 2006
- Arnason, Kelleher & Willmann 2008
- Looting the Seas iWatch News, 17 March 2012.
- Arnason, R; Kelleher, K; Willmann, R (2008). The Sunken Billions: The Economic Justification for Fisheries Reform. World Bank and FAO. ISBN 978-0-8213-7790-1.
- Beverton, R. J. H.; Holt, S. J. (1957). On the Dynamics of Exploited Fish Populations. Fishery Investigations Series II Volume XIX. Chapman and Hall (Blackburn Press, 2004). ISBN 978-1-930665-94-1.
- Beverton, R. J. H. (1992). Voigtlander, C.W, ed. "Session 4: The state of fisheries science". The State of the World's Fisheries Resources: Proceedings of the World Fisheries Congress, Plenary Sessions. Athens.
- Caddy JF and Mahon R (1995) "Reference points for fisheries management" FAO Fisheries technical paper 347, Rome. ISBN 92-5-103733-7
- Duffy, J. Emmett (2008) Marine biodiversity and food security Encyclopedia of Earth. Updated 25 July 2008.
- Elder, D. (2006). The Impact of Federal Fishing Policies on Coastal Maine and the Town of Harpswell Thesis. Dept. of Geography [ww.ccsu.edu Central Connecticut University].
- Froese, R and K Kesner-Reyes (2002)Impact of Fishing on the Abundance of Marine Species International Council for the Exploration of the Sea, ICES CM 2002/L:12.
- Gucinski, Hermann, Robert T. Lackey, and Brian C. Spence. 1990. Global climate change: policy implications for fisheries. Fisheries. 15(6):33-38. http://www.tandfonline.com/doi/pdf/10.1577/1548-8446%281990%29015%3C0033%3AGCCPIF%3E2.0.CO%3B2
- Hilbourn, Ray (2011) The evolution of quantitative marine fisheries management 1985–2010 Natural Resource Modeling, 25 (1): 122–144.
- Hlohowskyj, Ihor, Michael S. Brody, and Robert T. Lackey. 1996. Methods for assessing the vulnerability of African fisheries resources to climate change. Climate Research. 6(2): 97-106. http://www.citeulike.org/user/ltitodem/article/7144406
- Mahon, R.; McConney, P. (2004). "Managing the managers: improving the structure and operation of small fisheries departments, especially in SIDS". Ocean and Coastal Management 47 (9–10): 529–535. doi:10.1016/j.ocecoaman.2004.09.001.
- Lackey, Robert T. 2005. Fisheries: history, science, and management. pp. 121–129. In: Water Encyclopedia: Surface and Agricultural Water, Jay H. Lehr and Jack Keeley, editors, John Wiley and Sons, Inc., Publishers, New York, 781 pp. http://oregonstate.edu/dept/fw/lackey/FISHERIES-HISTORY-SCIENCE-AND-MANAGEMENT-REPRINT-2005.pdf
- McGoodwin JR (2001) Understanding the cultures of fishing communities. A key to fisheries management and food security FAO Fisheries, Technical Paper 401. ISBN 978-92-5-104606-7.
- Morgan, Gary; Staples, Derek and Funge-Smith, Simon (2007) Fishing capacity management and illegal, unreported and unregulated fishing in Asia FAO RAP Publication. 2007/17. ISBN 978-92-5-005669-2
- Pitcher T, D Pauly and P Hart (1999) Reinventing Fisheries Management, Kluwer Academic Publishers. ISBN 978-0-7923-5777-3
- Pitcher, TJ; Kalikoski, D; Pramod, G (2006). Evaluations of Compliance with the FAO (UN) Code of Conduct for Responsible Fisheries Fisheries Centre Research Reports 14 (2).
- Townsend, R; Shotton, Ross and Uchida, H (2008) Case studies in fisheries self-governance FAO Fisheries Technical Paper. No 504. ISBN 978-92-5-105897-8
- Voigtlander, C. W. (Ed.) 1994. The State of the World's Fisheries Resources. Proceedings of the World Fisheries Congress (Athens, 1992), Plenary Sessions. (Oxford & IBH Publishing Co. Pvt. Ltd., 66 Janpath, N.Delhi 110 001, INDIA). 204 p.
- Walters, Carl J. and Steven J. D. Martell (2004) Fisheries ecology and management Princeton University Press. ISBN 978-0-691-11545-0.
- UNEP (2007). Procedure for Establishing a Regional System of Fisheries Refugia in the South China Sea and Gulf of Thailand in the context of the UNEP/GEF project entitled: “Reversing Environmental Degradation Trends in the South China Sea and Gulf of Thailand”. South China Sea Knowledge Document No. 4. UNEP/GEF/SCS/Inf.4
- Evolution of Views of Fishery Management In: Sustaining Marine Fisheries (1999) Commission on Geosciences, Environment and Resources: Ocean Studies Board.
- FAO Code of Conduct for Responsible Fisheries
- FAO: Index of Fisheries and Aquaculture Technical Papers Rome.
- 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 Studies promoting ecosystem-based fisheries management.
- Fishery Management, an external wiki - 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 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
- Fisheries Management