This is Section 13.1 of the Arctic Climate Impact Assessment Lead Authors: Hjálmar Vilhjálmsson, Alf Håkon Hoel; Contributing Authors: Sveinn Agnarsson, Ragnar Arnason, James E. Carscadden, Arne Eide, David Fluharty, Geir Hønneland, Carsten Hvingel, Jakob Jakobsson, George Lilly, Odd Nakken,Vladimir Radchenko, Susanne Ramstad,William Schrank, Niels Vestergaard,Thomas Wilderbuer
This chapter identifies the possible effects of climate change on selected fish stocks and their fisheries in the Arctic. Arctic fisheries of selected species are described in the northeast Atlantic (i.e., the Barents and the Norwegian Seas), the waters around Iceland and Greenland, the waters off northeasternCanada, and the Bering Sea (Fig. 13.1). The species discussed are those few circumpolar species (capelin (Mallotus villosus), Greenland halibut (Reinhardtius hippoglossoides), northern shrimp (Pandalus borealis), and polar cod (Boreogadus saida)) and those of commercial importance in specific regions. The latter include Atlantic cod (Gadus morhua), haddock (Melanogrammus aeglefinus), Alaska pollock (Theragra chalcogramma), Pacific cod (Gadus macrocephalus), snow crab (Chionoecetes opilio), plus a number of others. Marine mammals are also considered in this chapter as they form an important component of northern marine ecosystems and several are of commercial importance.
This chapter focuses on the effects of climate change on commercial fisheries and the impacts on society as a whole. Chapters 9, 10, and 12 address the implications of fisheries and aquaculture for indigenous peoples.
This chapter is organized such that for each of the four regions the discussion follows a standard format: introduction; ecosystem essentials; fish stocks and fisheries; past climatic variations and their impact on commercial stocks; possible impacts of global warming on fish stocks; the economic and social importance of fisheries; past economic and social impacts of climate change on fisheries; economic and social impacts of global warming: possible scenarios; and ability to cope with change. The chapter concludes with a synthesis of the regional assessments of the impacts of climate change on arctic fisheries and societies, and with research recommendations.
Biological and model uncertainties/ certainties (13.1.1)
Precise forecasts of changes in fish stocks and fisheries and their effects on society are not possible.The sources of uncertainty can be grouped into three categories: (1) uncertainties in identifying the reasons for past changes in fish biology, (2) uncertainties in the projections of potential changes in the ocean climate under climate change scenarios, and (3) uncertainties relating to the socio-economic effects of changes in fish stocks.
There are many biological characteristics of fish that change in response to natural variability in the physical environment. However, when fish stocks are heavily exploited, as many arctic stocks have been, it has proven difficult to identify the relative importance of fishing and environment on observed changes in biology. Also, many fish stocks are currently much less abundant than in the past and are showing extreme changes in population characteristics.Thus, even if historical observations of variability in fish biology could be associated with past changes in ocean climate, it is not known whether the present populations would respond in a manner similar to the historical response.
Some of the uncertainties surrounding the response of the ocean to the projected changes in global climate discussed in Chapter 4 were addressed in Chapter 9. One of the most important components of the arctic environment is the thermohaline circulation. Possible changes in the thermohaline circulation and their consequences are described in section 126.96.36.199. Present climate models are considered to generate reasonably reliable projections of climate change at a global scale but are considered to generate less reliable results at the regional level. This results in uncertainty in evalua- tions of potential effects of climate change on the large marine ecosystems considered in this chapter.
Some key findings in Chapter 9 reflect a high degree of certainty about changes in the arctic seas. Although regional changes were not identified in Chapter 9, the chapter concludes that in most arctic areas upper water column temperatures are very likely to increase, especially in areas with reduced sea-ice cover and that increased water temperatures are very likely to lead to a northward shift in the distribution of many species of fish, to changes in the timing of their migration, to a possible extension of their feeding areas, and to increased growth rates. Chapter 9 also concludes that most of the present ice-covered arctic areas are very likely to experience reductions in sea-ice extent and thickness, especially in summer and that in areas of reduced sea-ice cover, primary production is very likely to increase, which in turn is likely to increase zooplankton and possibly fish production. In addition, Chapter 9 concludes that increased areas and periods of open water are likely to be favorable for some whale species and the distribution of these species is very likely to move northward. An expansion of their feeding grounds would presumably lead to an increase in their abundance.Thus, although the Chapter 9 conclusions are global in scale and do not identify specific changes in the four marine ecosystems considered here, they do provide, with a high degree of probability, a basis for considering these conclusions within the context of the fish stocks, fisheries, and possible effects on human societies resulting from the projected changes in the four areas.
Societal uncertainties (13.1.2)
Once fish population changes have been evaluated, it becomes necessary to relate those changes to changes in society.This raises new difficulties. Even when changes in fish populations are predictable to a high degree of accuracy, there is no deterministic relationship between these changes and those in society. Social change is driven by a number of different forces; with climate change only one of a number of natural factors. Also, humans are important drivers of change, through economic and political activities. It is extremely difficult to isolate the relative impact of the various drivers of change. In addition, societies have the capacity to adapt to change. Changes in fish stocks, for example, are met by adjustments in fisheries management practices and the way fisheries are performed.
The result of these uncertainties is that there are few firm predictions in this chapter. Instead, changes in potential effects and likely outcomes are considered.
The global framework for managing living marine resources (13.1.3)
A global framework for the management of living marine resources has been developed over recent decades, providing coastal states with extended jurisdiction over natural resources.The Third United Nations Law of the Sea Conference (UNCLOS) was convened in 1973 and ended nine years later with the adoption in 1982 of the United Nations Law of the Sea Convention, which lays down the rules and principles for the use and management of the natural resources in the ocean. The most important elements are the provisions that enable coastal states to establish exclusive economic zones (EEZs) up to 200 nautical miles (360 kilometers) from their coastal baselines. Coastal states have sovereign rights over the natural resources in their EEZs.The Convention also mandates that coastal states manage resources in a sustainable manner and that they be used optimally.Where fish stocks are shared among countries, they shall seek to cooperate on their management.
A country’s authority to manage fish stocks is defined by its 200 mile EEZ.Within its EEZ, a coastal state has sovereign rights over the natural resources, and therefore the authority to manage the living marine resources there. During the 1980s it became evident that the framework provided by the Convention was inadequate to cope with two major developments in fisheries worldwide: the dramatic increase in fishing in the high seas beyond the EEZs and a corresponding increase in catches within the EEZs. Both developments were driven by rapidly growing fishing capacity. The consequence was that many stocks were overfished. A treaty was therefore negotiated under the auspices of the United Nations to supplement the Convention, seeking to provide a legal basis for restricting fisheries on the high seas and introducing more restrictive management principles, enhanced international cooperation in management, and improved enforcement of management measures.The Agreement for the Implementation of the Provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 Relating to the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks (The UN Fish Stocks Agreement) was thus adopted in 1995 and mandates the application of a precautionary approach to fisheries management. It also emphasizes the need for cooperation between countries at a regional level in this respect.These two elements have proved crucial in the development of international fisheries conservation and management policies since the mid-1990s, not least in arctic areas. Existing regional arrangements have been improved upon in order to implement the agreements. This applies to the Northwest Atlantic Fisheries Organization (NAFO), which covers the Northwest Atlantic, and the North East Atlantic Fisheries Commission (NEAFC), which covers the international waters in the Northeast Atlantic. An agreement placing a moratorium on fishing on the high seas in the Bering Sea has been in force since 1994.
The development of this global framework for fisheries management has been accompanied by a corresponding development of fisheries management regimes in individual countries. The design and performance of such regimes are crucial to the fate of fish stocks. At the global level, the major challenges to fisheries management are related to the need to reduce a substantial overcapacity in the world’s fishing fleets, and the need to introduce more sustainable management practices. To achieve the latter, countries are introducing precautionary approaches to fisheries management – a crucial requirement of the 1995 UN Fish Stocks Agreement. In addition, ecosystem-based approaches to the management of living marine resources, where natural factors such as climate change are taken into account in decision- making, are under development. The 2002 World Summit on Sustainable Development stated in its implementation plan that ecosystem-based approaches to management are to be in place by 2010.
All arctic countries with significant fisheries have well established resource management regimes with comprehensive systems for producing the knowledge base required for management, the promulgation of regulations to govern fishing activities, and arrangements to ensure compliance with regulations.While the various regimes vary considerably with regard to the design of management policies, the challenges they confront in attempting to reduce overcapacity and in introducing precautionary approaches to fisheries are similar.
For marine mammals there is a single international body at the global scale, and several regional bodies. At the global scale the 1946 International Convention for the Regulation of Whaling mandates an International Whaling Commission (IWC) to regulate the harvest of great whales. A moratorium on commercial whaling was adopted in 1982. A number of countries, among them Norway and Russia, availed themselves of their right under the convention not to be bound by this decision. Canada and Iceland left the Commission due to the preservationist developments there. Iceland rejoined the Commission in 2003.The North Atlantic Marine Mammal Commission (NAMMCO) is tasked with the management of marine mammals in the North Atlantic.
Chapter 13: Fisheries and Aquaculture
13.2 Northeast Atlantic – Barents and Norwegian Seas
13.3 Central North Atlantic – Iceland and Greenland
13.4 Newfoundland and Labrador Seas, Northeastern Canada
13.5 North Pacific – Bering Sea
13.6. Synthesis and key findings
13.7. Research recommendations