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Lead Authors:  Hans Meltofte, Henry P. Huntington and Tom Barry 


Inukshuk (Cairn) Photo: Larry Maurer, Shutterstock

The Arctic is home to a diverse array of plants and animals. They are adapted in various ways to a region that is often cold, experiences prolonged daylight in summer and equally lengthy darkness in winter, and includes habitats that range from ice caps to wetlands to deserts, from ponds to rivers to the ocean. Some of the Arctic’s species are icons, such as the polar bear, known throughout the world. Some are obscure, with many yet to be discovered. Arctic peoples, too, have adapted to this environment, living off the land and sea in keeping with the cycles of the seasons and the great migrations of birds, mammals and fish. Many birds, for example, spend the summer in the Arctic and are absent in winter, having flown to all corners of the Earth, thus connecting the Arctic with every region of the planet.

Today, Arctic biodiversity is changing, perhaps irreversibly. This introduction summarizes some of the main stressors as described in a series of Arctic Council assessments. Many of these threats have been the subject of intense research and assessment, documenting the impacts of human activity regionally and globally, seeking ways to conserve the biological and cultural wealth of the Arctic in the face of considerable pressures to develop its resources. These assessments have focused primarily on individual drivers of change.

The Arctic Biodiversity Assessment (ABA) focuses on the species and ecosystems characteristic of the Arctic region and draws together information from a variety of sources to discuss the cumulative changes occurring as a result of multiple factors. It draws on the most recent and authoritative scientific publications, supplemented by information from Arctic residents, also known as traditional ecological knowledge (TEK). The chapters of the ABA have been through comprehensive peer reviews by experts in each field to ensure the highest standards of analysis and unbiased interpretation (see list below). The results are therefore a benchmark against which future changes can be measured and monitored.

The purpose of the ABA, as endorsed by the Arctic Council Ministers in Salekhard, Russia, in 2006 is to

Synthesize and assess the status and trends of biological diversity in the Arctic … as a major contribution to international conventions and agreements in regard to biodiversity conservation; providing policymakers with comprehensive information on the status and trends of Arctic biodiversity (CAFF 2007).

The intent is to provide a much needed description of the current state and recent trends in the Arctic’s ecosystems and biodiversity, create a baseline for use in global and regional assessments of Arctic biodiversity and a basis to inform and guide future Arctic Council work. The ABA provides up-to-date knowledge, identifies gaps in the data record, describes key mechanisms driving change and presents suggestions for measures to secure Arctic biodiversity. Its focus is on current status and trends in historical time, where available.



For this assessment a more scientific definition of the Arctic was needed than the CAFF boundaries, which are defined as much by political boundaries as by climatic and biological zoning, and therefore vary considerably among the Arctic nations. That such a clear definition is a prerequisite for a meaningful account of Arctic biodiversity can be illustrated by the highly varying numbers of ‘Arctic’ bird species found in the literature. By including huge tracts of boreal forest and woodland into the Arctic, as politically defined by CAFF, figures of up to “450 Arctic breeding bird species” have been quoted (Zöckler 1998, Trouwborst 2009) as compared with the circa 200 species given in the present report based on a stricter ecological definition (Ganter & Gaston, Chapter 4).

The name Arctic derives from the ancient Greek word Arktikós, meaning the land of the North. It relates to Arktos, the Great Bear, which is the star constellation close to the Pole Star. There are several definitions of the Arctic. From a geophysical point of view, the Arctic may be defined as the land and sea north of the Arctic Circle, where the sun does not set on the summer solstice and does not rise on the winter solstice. From an ecological point of view, it is more meaningful to use the name for the land north of the tree line, which generally has a mean temperature below c. 10-12 °C for the warmest month, July (Jonasson et al. 2000). With this definition, the Arctic land area comprises about 7.1 million km2, or some 4.8% of the land surface of Earth.  Similarly, the Arctic waters are defined by characteristics of surface water masses, i.e. the extent of cold Arctic water bordering temperate waters including ‘gateways’ between the two biomes. The Arctic Ocean covers about 10 million km2 (see Michel, Chapter 14 for details).

The vegetated lowland of the Arctic is often named tundra, which originates from the Saami word tundar, meaning treeless plain. In general, the low Arctic has much more lush vegetation than the high Arctic, where large lowland areas may be almost devoid of vegetation, like the Arctic deserts of the northernmost lands in the world.  The sub-Arctic or forest tundra is the northernmost part of the boreal zone, i.e. the area between the timberline and the tree line. Hence, the sub-Arctic is not part of the Arctic, just as the sub-tropics are not part of the tropics. Like the Arctic, the word boreal is derived from Greek: Boreas was the god of the cold northern winds and bringer of winter. Related zones are found in mountainous areas outside of the Arctic as sub-alpine, low-alpine and high-alpine biomes.

This assessment follows the Circumpolar Arctic Vegetation Map’s (CAVM Team 2003) definition of the Arctic, since this map builds on scientific criteria for Arctic habitats. Furthermore, inclusion of tree-covered sub- Arctic habitats would have expanded the volume of species and ecosystems beyond achievable limits. Yet, different chapters may cover additional bordering areas as needed to provide scientific and ecological completeness. The entire Arctic tundra region (sub-zones A-E on the CAVM) is addressed as comprehensively as possible in terms of species and ecosystem processes and services. Oceanic tundra (e.g. the Aleutian Islands), the sub-Arctic and other adjacent areas are addressed as appropriate in regard to (1) key ecosystem processes and services, (2) species of significance to the Arctic tundra region, (3) influences on the Arctic tundra region, and (4) potential for species movement into the current Arctic tundra region, e.g. due to global change.

For the separation between the high Arctic and the low Arctic, we follow the simplest division which is between sub-zones C and D on the CAVM. The southern limit of the sub-Arctic is ‘loose’, since work on a CAFF Circumpolar Boreal Vegetation Map is pending (CBVM 2011). Contrary to the Arctic zones on land, the boundaries at sea are tentative, and on Fig.1 they are indicated only with rough boundaries between the different zones.



According the Convention on Biological Diversity (CBD), biodiversity is

the variability among living organisms from all sources, including, inter alia, terrestrial, marine, and other aquatic ecosystems, and the ecological complexes of which they are part: this includes diversity within species, between species and of ecosystems.

Similarly, ecosystems are defined as

a dynamic complex of plant, animal and micro-organism communities and their non-living environment interacting as a functional unit.

As also stated by the CBD

biological diversity is about more than plants, animals and micro organisms and their ecosystems – it is about people and our need for food security, medicines, fresh air and water, shelter, and a clean and healthy environment in which to live.

Hence, in the present report, humans are both considered part of the ecosystems and as outside agents influencing the environment. The main focus, however, remains on status and trends in ‘non-human’ biodiversity.

This assessment covers all three aspects of biological diversity: species, ecosystems and genetic variation. Chapters 3-11 deal with taxonomic groups, Chapters 12-14 cover major ecosystems, Chapters 15 and 16 deal with two functional groups (parasites and invasive species, respectively), and Chapter 17 addresses genetic diversity. Finally, Chapters 18-20 deal with ecosystem services and other aspects of the human relationship with nature, including linguistic diversity.

Since there is no strict definition of an Arctic species, this assessment includes all species that reproduce in and/or have more than peripheral populations in the Arctic as defined above, i.e. excluding species with accidental or clearly insignificant appearance within the Arctic. Sub-Arctic species and ecosystems are dealt with as outlined above, i.e. where they have direct bearing on the Arctic but not for their own sake. Similarly, ecosystems are included if they have a substantial presence within the Arctic (see e.g. the CAVM).

Regarding distinction between marine, freshwater and terrestrial, in this report the marine includes everything up to the high water mark (i.e. including the intertidal zone). Fens and marshes are considered terrestrial, whereas tarns and ponds are considered freshwater ecosystems together with lakes, rivers and streams.

The organizing principles for the chapters are:

  • The species chapters focus on status and trends in distribution, population densities and abundance (population size).
  • For some taxa, species lists etc. are given in digital appendixes.
  • In the ecosystem chapters, the focus is on status and trends in distribution, composition (habitat and species richness), productivity (e.g. greening), phenology and processes (e.g. grazing and predation).
  • Causal explanations of observed changes are provided to the extent that the scientific literature offers analyses or descriptions thereof.
  • Similarly, to the extent that the scientific literature holds modeling or other information on future prospects for Arctic biodiversity and ecosystems within the 21st century – including anticipated tipping points and thresholds – these are referred to as well.
  • Information from holders of traditional knowledge has been considered in all chapters, in addition to a section on Indigenous peoples and biodiversity in the Arctic, which follows this Introduction.
  • Cumulative effects are considered where relevant.
  • Every effort has been made to avoid bias towards selective reporting of either positive or negative trends.



Climatically, ecologically, culturally, socially and economically, the Arctic is changing in many ways with implications throughout the region and around the world. In order to set the stage for assessing biodiversity, and to avoid repeating the same descriptions in each chapter, this section summarizes the main findings of major assessments undertaken within the Arctic Council, as these assessments have covered most of the major drivers of change. This section is not intended to be comprehensive, but rather to show the urgency and the timeliness of the ABA. Many changes are rapid and even accelerating, and the various assessments conducted in recent years make possible an examination of the combined effects of multiple stressors.


The Arctic climate is warming rapidly (ACIA 2005). Summer sea ice extent has diminished greatly in recent years, more of the Greenland ice cap is melting than before, and permafrost is thawing (AMAP 2009a, 2011a, 2011b). All of these changes affect Arctic ecosystems, as described in detail in this ABA. The Arctic Council, in cooperation with the International Arctic Science Committee (IASC), produced in 2005 the Arctic Climate Impact Assessment (ACIA), which compiled into one document the information available at that time concerning the changing climate of the Arctic and the resulting effects on the cryosphere, ecosystems and human activities. Since that time, the Arctic Council has contributed to updates concerning various aspects of climate change in the Arctic. This recent information shows that the projections of the ACIA were, if anything, conservative (AMAP 2009a). Newer updates now include biological information, which will allow better monitoring and reporting of the effects of climate change on biodiversity.


The Arctic has abundant petroleum and mineral resources, the development of which has been slowed only by the costs of operating in remote areas with a harsh climate. Nonetheless, oil and gas fields in the Arctic provide a substantial part of the world’s supply at present, and many fields have yet to be developed. The Arctic Monitoring and Assessment Programme (AMAP)’s assessment, Oil and gas activities in the Arctic: effects and potential effects, describes the petroleum reserves of the Arctic, development to date, likely development in the next two decades, and effects on ecosystems and society (AMAP 2009b). The pace of development will ref lect global demand as well as decisions by Arctic governments on the regulation of oil and gas activities and the capture of revenues from them. To date, oil and gas and other developments have had substantial though largely localized impacts on the environment. Further development, particularly the threat of oil spills and the introduction of invasive species in the marine environment, nonetheless poses a risk to much of the Arctic region.

Cultural and social change

Within living memory in many parts of the Arctic, local societies and economies have become ever more connected with the wider world through telecommunications, trade, travel and other influences and interactions. Today, monetary economies, national and regional governmental institutions, formalized educational systems, modern health care and new forms of communications are among the many factors shaping the lives of Arctic residents. While some changes have been highly beneficial, as seen in longer life expectancy and decreased infant mortality, other changes have disrupted traditional ways of life and contributed to environmental degradation. The Sustainable Development Working Group (SDWG) of the Arctic Council published the Arctic Human Development Report (AHDR) in 2004, examining a range of issues affecting Arctic peoples. Connection to the environment remains a vital part of the quality of life for many Arctic residents, as well as the foundation for Arctic cultures, but those connections are under threat from many directions (AHDR 2004). The SDWG is currently working on a follow-up to the AHDR.


As sea ice retreats, the prospects for shipping in the Arctic increase. The Northern Sea Route across the top of Eurasia has been used by icebreakers and ice-strengthened ships since the 1930s, primarily for transportation within Russia. A regular ice-free summer season would make the route attractive for through-shipping between East Asia and Europe, cutting thousands of kilometers off current routes. Recent summers have seen a few cargo ships making this voyage. The Northwest Passage through the Canadian Archipelago also offers the prospect of shorter shipping routes and improved access to the region’s resources, though not expected to become a transit shipping route for some time. The Protection of the Arctic Marine Environment (PAME) Working Group of the Arctic Council completed the Arctic Marine Shipping Assessment (AMSA) in 2009, evaluating the prospects for future shipping activity as well as resulting environmental, economic and social impacts (AMSA 2009). Much of the outcome for shipping depends on the governance regimes that are established in both territorial and international waters by the Arctic states and the global demand for Arctic resources. Increased shipping is also likely to increase Arctic resource development through improved access and lower costs. Local transportation has also improved over recent decades, with the widespread use of motorboats and mechanized snow travel (snowmobiles), as well as regular air service to many parts of the Arctic providing easier access to goods and services from the south.


Persistent organic pollutants (POPs) and heavy metals accumulate in Arctic ecosystems, despite being produced and released at far higher rates in temperate and tropical regions. Contaminants can be transported to the Arctic via ocean currents, large rivers and the atmosphere. In a cold climate, some of these substances tend to settle from the air onto land or into water and then stay there. Other substances, like mercury, have a more complex chemical cycle. These contaminants can accumulate in organisms at the bottom of the food web, and the concentrations of many of these substances magnify as they move from one trophic level to the next. Species at the top of the food web, such as seals and polar bear as well as humans who eat Arctic species, can be exposed to high levels of these contaminants, posing health risks in some instances. AMAP has conducted several assessments of contaminants in the Arctic (AMAP 1998, 2004, 2009c, 2011c). One result of this information was strong scientific and political motivation for the Stockholm Convention on POPs, a global agreement signed in 2001 that explicitly acknowledged concern for Arctic peoples and ecosystems. The biological and ecological impacts of contaminants remain subjects of research in the Arctic, particularly as climate change may alter contaminant transport and uptake (AMAP 2011c, UNEP/AMAP 2011).


The Ottawa Declaration of 1996 formally established the Arctic Council as a high-level, consensus-based, intergovernmental forum to provide a means for promoting cooperation, coordination and interaction among the Arctic states, with the involvement of the Arctic indigenous communities and other Arctic inhabitants on common Arctic issues, in particular issues of sustainable development and environmental protection in the Arctic. The Arctic Council is comprised of eight Arctic states and six Permanent Participants that represent the Indigenous Peoples of the circumpolar north. The Arctic Council is unique among intergovernmental forums in that both Arctic states and Permanent Participants have a seat at the same table. Several observer states, intergovernmental and interparliamentary organizations6 and non-government organizations7 also make valuable contributions to the Council’s work.

The Arctic Council members have recognized that their shared ecosystems with unique flora and fauna are fragile and threatened from a number of causes, and that changes in Arctic biodiversity have global repercussions (AEPS 1991). The Conservation of Arctic Flora and Fauna (CAFF) working group was established in 1991 under the Arctic Environmental Protection Strategy (AEPS, a precursor to the Arctic Council) in order to encourage the conservation of Arctic f lora and fauna, their diversity and their habitats. CAFF was subsequently incorporated within the Arctic Council.

CAFF’s mandate is to address the conservation of Arctic biodiversity and to communicate the findings to the governments and residents of the Arctic, helping to promote practices which ensure the sustainability of the Arctic’s resources. CAFF serves as a vehicle for cooperation on species and habitat management and utilization, to share information on management techniques and regulatory regimes, and to facilitate more knowledgeable decision-making. It provides a mechanism for developing common responses to issues of importance for the Arctic ecosystems such as development and economic pressures, conservation opportunities and political commitments.

The objectives assigned to CAFF are (CAFF 1995):

  • to collaborate for more effective research, sustainable utilization and conservation,
  • to cooperate to conserve Arctic f lora and fauna, their diversity and their habitats,
  • to protect the Arctic ecosystem from human-caused threats,
  • to seek to develop more effective laws, regulations and practices for f lora, fauna and habitat management, utilization and conservation,
  • to work in cooperation with the Indigenous Peoples of the Arctic,
  • to consult and cooperate with appropriate international organizations and seek to develop other forms of cooperation,
  • to regularly compile and disseminate information on Arctic conservation, and
  • to contribute to environmental impact assessments of proposed activities.

Achieving success in conserving Arctic natural environments, while allowing for economic development, depends on obtaining and applying comprehensive baseline data regarding status and trends of Arctic biodiversity, habitats and ecosystem health. This need to identify and fill knowledge gaps on various aspects of Arctic biodiversity and monitoring was identified in the Arctic Council’s Strategy for the Conservation of Arctic Biodiversity (CAFF 1997) and reinforced by the Arctic Flora and Fauna report (CAFF 2001) and the Arctic Climate Impact Assessment (ACIA 2005), which recommended that long-term Arctic biodiversity monitoring be expanded and enhanced.

CAFF responded with the implementation of the Circumpolar Biodiversity Monitoring Program (CBMP). The CBMP is an international network of scientists, government agencies, indigenous organizations and conservation groups working to harmonize and integrate efforts to monitor the Arctic’s living resources. Following the establishment of the CBMP, it was agreed that it was necessary to provide policy makers and conservation managers with a synthesis of the best available scientific and traditional ecological knowledge (TEK) on Arctic biodiversity. The ABA will serve as a baseline upon which the CBMP will build, providing up-to-date status and trends information to support ongoing decision-making and future assessments of the Arctic’s biodiversity.

To take stock of the current state of biodiversity in the Arctic, the ABA was endorsed by the Arctic Council in 2006 (Salekhard Declaration). The ABA has been an inclusive process which has harnessed the efforts of 251 scientists from 10 countries including both Arctic and non-Arctic states. Co-lead authors for each chapter were appointed from North America and Eurasia in order to seek a balanced approach. TEK was recognized as an important contribution to provide ‘eye-witness’ observations on the status and trends in Arctic biodiversity, and a process was put in place to allow for the incorporation of TEK within the ABA (Mustonen & Ford 2013).  TEK coordinators were appointed for Eurasia and North America and compiled TEK material into a reference document to inform the ABA (Mustonen & Ford 2013).

The first deliverable from the ABA process was Arctic Biodiversity Trends: Selected Indicators of Change (CAFF 2010), which presented a preliminary assessment of status and trends in Arctic biodiversity and was based on a suite of 22 indicators developed by the CBMP. The 2010 report was the Arctic Council’s contribution to the United Nations International Year of Biodiversity in 2010 and its contribution to the CBD’s 3rd Global Biodiversity Outlook to measure progress towards the 2010 Biodiversity Targets (CBD 2010a). The CBD COP11 welcomed the report and noted its key findings. Changes in Arctic biodiversity can have global implications (CAFF 2010), and it is critical to ensure that information on such changes is linked into international agreements and legal frameworks. The CBD has recognized the importance of Arctic biodiversity in a global context, and highlighted the need for continued collaboration between the CBD and CAFF to contribute to the conservation and sustainable use of the Arctic’s living resources (CBD 2010b), in particular with regards to monitoring and assessing status and trends, and stressors to Arctic biodiversity. CAFF was requested to provide information on status and trends in Arctic biodiversity to inform the next Global Biodiversity Outlook report.

The ABA has benefited from the broad range of research efforts generated by the International Polar Year (IPY) 2007-2008. It contributes to the legacy of IPY by providing a means of integrating and allowing IPY research to reach a wider audience.

A key challenge for conservation in the Arctic and globally is to shorten the gap between data collection and policy response. CAFF has recognized this challenge and in recent years has worked towards developing a solution. This approach has focused on not just developing traditional assessments but also addressing the collection, processing and analysis of data on a continuous basis. Indeed, the ABA provides a baseline of current knowledge, closely linked to the development of the CBMP as the engine for ongoing work, including the production of regular and more flexible assessments and analyses.