Key Finding 1: Arctic biodiversity is being degraded, but decisive action taken now can help sustain vast, relatively undisturbed ecosystems of tundra, mountains, fresh water and seas and the valuable services they provide.
Arctic species today enjoy large areas of habitat that support a full range of ecological processes and interactions. But climate change, industrial development, pollution, local disturbances and invasive alien species are affecting the Arctic, and their impacts are increasing. The most visible changes in the Arctic are those to the physical environment, including warming temperatures, the loss of sea ice and an increasing collective footprint from industrial activities. The resulting ecological impacts are often much harder to see. Yet these changes are important to consider now, since impacts being felt today may take years or decades to show their full effect. Stressors do not act in isolation, and often exacerbate one another, leading to greater cumulative impacts than expected from individual activities or stressors. The world has seen many examples of long-term ecological damage due to increasing human activity. This assessment has demonstrated that, in the Arctic, we still have an opportunity to act before it is too late.
Globally, habitat loss and degradation pose the main threats to biodiversity. The relative well-being of many Arctic ecosystems today is largely the fortuitous result of a lack of intensive human encroachment, thanks to the extreme climate and long distance from major population and economic centers. This history does not guarantee a healthy future. It does, however, provide humankind with a rare opportunity to create spaces where ecosystems and species can evolve naturally, and indigenous cultures can continue to practice traditional ways of life. Conservation of Arctic biodiversity will no longer happen by default. It is possible only if decisive actions are taken now, to conserve for posterity the Arctic legacy that enriches the world today.
Key Finding 2: Climate change is by far the most serious threat to Arctic biodiversity and exacerbates all other threats.
Summer temperatures in the Arctic during recent decades have been warmer than at any time in the past 2000 years, and the region is warming twice as fast as the rest of the planet. Within this century, temperatures in the Arctic are projected to increase by several degrees further from the 1980-2000 average. Changing combinations of high temperatures, winds and precipitation are likely to give rise to very different climates in the Arctic. Arctic summer sea ice cover – and particularly the amount of multi-year ice – is decreasing at an accelerating rate. The years since 2007 have seen less summer sea ice than any previous year in the satellite era, and 2012 set another record low. The ocean is expected to become ice free in summer within a few decades. The increased carbon dioxide concentrations in the atmosphere are also leading to acidification of ocean waters worldwide, especially in colder Arctic waters that can dissolve more carbon dioxide. Warming is also causing loss of permafrost and glaciers, affecting hydrology, vegetation, erosion patterns and other features of terrestrial ecosystems.
The distribution of flora and fauna is shifting northwards as the Arctic continues to warm. On land, shrubs are growing taller and spreading, boreal species and ecosystems are already moving into what is now the low Arctic, and the treeline is expected to move north. While low Arctic species are expected to move into the high Arctic, some high Arctic species and ecosystems are expected to disappear or remain only as isolated fragments in high mountain areas. In the ocean, loss of sea ice is already affecting the timing and patterns of primary production, altering food webs and reducing the availability of sea ice to walrus and ice seals for resting, molting, breeding and rearing young. The total loss of some key habitats such as multi-year pack ice is expected. In the process of rapid change and transitions, new combinations of species are altering Arctic ecosystems.
By increasing the accessibility of the Arctic to humans, climate-induced changes will facilitate increased industrial activity such as oil and gas exploration and marine shipping. These changes will in turn bring other stressors to the region. For example, ships discharging ballast water into Arctic seas may introduce invasive species that may outcompete and displace resident species. The stress of climate change does not act in isolation, but works in conjunction with other stressors, yielding even greater risks to Arctic biodiversity.
Key Finding 3: Many Arctic migratory species are threatened by overharvest and habitat alteration outside the Arctic, especially birds along the East Asian flyway.
Overharvest and habitat loss and degradation threaten some Arctic migratory species throughout their global ranges. The Eskimo curlew has likely gone extinct as a result of overharvest outside the Arctic, and the spoon-billed sandpiper faces extinction now due in part to overhunting in its wintering areas in southeast Asia. Loss of staging and wintering habitat for waterfowl and shorebirds, for example, is occurring at an alarming rate in many areas, especially in East Asia around the Yellow Sea. The loss of coastal and intertidal habitat is expected to increase considerably with sea level rise and increasing development. Some migratory marine mammals that occur in the Arctic during part of their migration are also experiencing habitat loss or degradation outside the Arctic as well, but these alterations are poorly documented at present.
Threatened migratory species require protection throughout the year, across their full migratory range and across multiple international boundaries. Effective management in one region can be undermined by harmful actions elsewhere. Arctic birds migrate far and wide, so Arctic migratory bird conservation is a truly global issue, of great importance to ecosystems and overall biodiversity in the Arctic and beyond.
Key Finding 4: Disturbance and habitat degradation can diminish Arctic biodiversity and the opportunities for Arctic residents and visitors to enjoy the benefits of ecosystem services.
Roads, noise, pipelines, dams, drilling and mine sites, destructive fishing practices and other forms of direct and indirect damage to habitats and species are putting increasing pressure on the Arctic environment in some areas. Some commercial fishing techniques such as bottom trawling have the potential to damage sensitive seafloor habitats and their ecological communities. Construction of roads and pipelines has led to fragmentation of landscapes, permafrost degradation and changes in vegetation and hydrology. Noise from offshore seismic exploration and drilling affects the behavior of bowhead whales and other species. Although reindeer grazing can benefit biodiversity in several ways and could be instrumental in counteracting some of the effects of climate change, grazing has caused degradation locally in the Arctic in particular in regions where their habitat has been fragmented.
The majority of these stressors currently result from oil, gas and mineral exploitation on land. Offshore oil and gas exploration and production are in their early stages in the Arctic region, but are expected to increase in the coming decades, producing impacts from noise and other habitat disturbance. These effects may persist long after the activity ceases. Where the causes of habitat degradation have been removed, recovery is typically slow in the Arctic. To date, most of the impacts have been relatively localized, although the activities are taking place in many regions of the Arctic and are expected to increase.
The extent of the effects that these human disturbances can have in displacing species from important habitats is often closely related to their spatial needs and specific behaviors. Species that require large areas of undisturbed habitat, such as caribou and reindeer, are sensitive to habitat loss and fragmentation from development activities such as road construction in and around calving grounds. Populations that are heavily hunted are often more easily displaced by human activity. Intensive land- and seascape planning could minimize harmful effects from localized disturbances and ensure that increases in human populations and industrial activity are managed in ways that sustain a rich biodiversity.
Key Finding 5: Pollution from both long-range transport and local sources threatens the health of Arctic species and ecosystems.
Pollution can affect the health of individual animals and, in severe cases, the productivity and functioning of an ecosystem. Relatively high levels of contaminants have been documented in several Arctic animals, including polar bears, beluga whales and some seabirds, but there is as yet little scientific evidence that these have had an effect at the population level. Climate change affects the pathways of contaminants in the environment, including the release of contaminants previously captured by ice and permafrost. Increasing industrial activity in the Arctic will also lead to more potential local sources of pollution as well.
Persistent organic pollutants and heavy metals such as mercury, lead and cadmium from sources far to the south reach the Arctic by air and water. Once there, they accumulate through the food web and affect the health of individual animals and humans. Some contaminants such as DDT and PCBs are decreasing following concerted international action such as the Stockholm Convention on Persistent Organic Pollutants, but other existing and newly developed contaminants are still widely used. In addition, ozone-depleting chemicals in the stratosphere can lead to increasing exposure to ultraviolet light, potentially harming living organisms.
Mining, oil and gas activities, Arctic settlements and legacy sites such as military bases are current and potential sources of pollution, litter, sewage and black carbon within the Arctic. The risk of major oil spills is a serious threat for marine ecosystems, particularly those associated with sea-ice, because response can be difficult and spilled oil is likely to persist for a long time. Oil spills are a lesser, but still very important, threat for terrestrial and freshwater systems. Legacy contaminants and radioactivity from past military and other human activity have impacted and will continue to impact biodiversity in the region. Arctic communities often have an impact in their local area, and reducing those impacts will benefit the local environment and contribute to global efforts to reduce pollution.
Key Finding 6: There are currently few invasive alien species in the Arctic, but more are expected with climate change and increased human activity.
Globally, invasive non-native species are considered the second most important threat to biodiversity after habitat loss. These are species introduced by human activity that may flourish and spread in their new environment, threatening native species and ecosystem functions. Although some known invasive non-native species are found in the Arctic, the problem has been less acute than in other regions of the world. To date, invasive alien plants have reached the low Arctic in Alaska. Over a dozen terrestrial invasive non-native plant species are known from the Canadian low and high Arctic. Even on the high Arctic archipelago of Svalbard, nine non-native plant species have been found to reproduce. The Nootka lupin, introduced to control erosion in Iceland, has invaded sub Arctic heathland vegetation in almost all of Iceland. It has also been found in southwest Greenland, though it is not yet known to have spread into tundra vegetation there. The status of aquatic invasive non-native species in the Arctic and sub-Arctic is even less well known, but benthic communities in northern Norway and the Kola Peninsula are already facing disturbance from the introduced Pacific red king crab.
In the future, many non-native terrestrial species already present in sub-Arctic ecosystems may become invasive and move north, aided by climate change, human settlement and industrial activity. Similarly, Arctic shipping and increasing development may allow invasive non native marine organisms into the Arctic in unmanaged ballast water or on ship hulls and drilling rigs. Pathogens and disease vectors, too, may arrive with other invasive species. Combating invasive species is extremely difficult. Prevention is the best option if the Arctic is to be spared the severe impacts seen from this threat elsewhere in the world.
Key finding 7: Overharvest was historically the primary human impact on many Arctic species, but sound management has successfully addressed this problem in most, but not all, cases.
Small-scale, traditional harvest of mammals, birds and fish has provided the foundation for Arctic societies since humans first arrived in the region, and continues to do so today for many people in the Arctic. During the last few hundred years, the arrival of newcomers to the Arctic, and the introduction of modern hunting technologies resulted in some mammals experiencing severe population declines such as bowhead whales and walrus in large parts of the Arctic. The Steller’s sea cow and great auk went extinct in the mid-eighteenth and mid-nineteenth century. At the same time, previously sustainable traditional harvest practices were often ignored or disrupted. In some cases local harvest has also resulted in population declines, as is the case with some seabirds in Greenland in the 20th century. Continued human immigration, population growth technological advances and commercial markets for wildlife products resulted in increased harvest pressure on some wildlife populations. Populations of some depleted species, such as bowhead whales, muskox, some fish stocks and many migratory birds that declined sharply, have subsequently recovered or are showing signs of recovery.
Even though overharvest was the most significant recent historical pressure on many Arctic wildlife species, it is also the most manageable. In most areas, hunting and fishing activities that might threaten fish, mammal and bird populations are now regulated for species where there is conservation concern. As a result, the historical pressure from overharvest has been largely removed as a major threat for most species. Nevertheless, some areas where overharvest occurred still have the legacy of diminished wildlife populations and hunting opportunities, for example for walrus and thick-billed murres. Improved management and conservation actions are based on greater understanding of the potential for harm to species and ecosystems, better regulation and enforcement, and in many cases on greater engagement with Arctic peoples. The incorporation of traditional values, practices and knowledge can help improve both management and enforcement.
At the same time, new harvest ventures bring new risks of overharvest. There is increasing concern that the global demand for seafood outside the Arctic combined with increasing accessibility of Arctic seas as a result of sea-ice loss creates the potential for increased risks to poorly known fish and crustacean stocks. This risk can be reduced by effective regulation and enforcement that respect principles and practices for sustainable management.
Key Finding 8: Current knowledge of many Arctic species, ecosystems and their stressors is fragmentary, making detection and assessment of trends and their implications difficult for many aspects of Arctic biodiversity.
Effective, targeted conservation actions require reliable, up-to-date, easily accessible information. For example, successes in addressing overharvest stem in large part from accurate data on population size, reproduction rates and other parameters. International negotiations to reduce some contaminant emissions succeeded in large part because of strong scientific evidence for the worldwide transport of these substances and their uptake and impacts in biological systems, including humans.
From the present assessment, the overall status of Arctic biodiversity is clear in general terms. It is equally evident, however, that important knowledge about the majority of Arctic biodiversity remains to be documented. While the distributions of many mammals, birds and vascular plants are known, large gaps exist in knowledge about even the distribution of most other species—not to mention the many species likely remaining to be discovered. When it comes to population densities, sizes and trends, the knowledge gaps grow significantly larger. Even some commonly harvested species of mammals, birds and fish are not monitored adequately to ensure accurate and early determination of population trends. Most species that are not harvested or of direct value to humans are not monitored at all. Even for the few species where adequate, ongoing monitoring exists, the mechanisms that drive these population trends are in most cases poorly understood at best.
If decisions regarding human activity in the Arctic are to be supported with adequate, timely and up-to-date biodiversity information, there is a need for concerted efforts to collect, analyze and make readily available those data. Improved inventories, baselines, monitoring and research are needed, involving Arctic peoples and their knowledge. Key indicators of ecosystem structure and function should be identified to contribute to ecosystem-based approaches to monitoring and management, as in the case of CAFF’s Arctic Marine Biodiversity Monitoring Plan. Filling gaps in our knowledge is particularly crucial for important aspects of invertebrates, microbes, parasites and pathogens. These organisms are vital for ecosystem functioning but are all too often overlooked in the documentation and assessment of biodiversity and ecosystem health.
Key Finding 9: The challenges facing Arctic biodiversity are interconnected, requiring comprehensive solutions and international cooperation.
Climate change affects the physical environment, with consequent impacts on ecosystems and species as well as the mobilization of contaminants. Human activity in the Arctic may increase due to improved access and rising global demand for resources. Risks from pollution such as oil spills will increase as Arctic development proceeds. Pathways for invasive species to reach the Arctic will become more numerous as more ships travel north and more roads are built. More activity also means a greater potential for habitat degradation. And more activity may mean more people, who may increase fishing and hunting pressures.
Individually, each of these challenges places stress on Arctic biodiversity, as outlined in previous key findings. Together, they create a web of stresses and impacts that cannot be successfully addressed in isolation from one another. Both in the Arctic and globally, biodiversity must be conserved in a holistic fashion, so that efforts to reduce one stressor do not unintentionally make the effects of another stressor worse.
The habitat needs of migratory species, long-range transport of persistent contaminants, global shipping lanes and the geography of ecosystems do not follow political boundaries. Thus, international cooperation is increasingly needed to fully address the conservation challenges that face Arctic biodiversity now and in the decades to come. The recommendations that follow recognize the interconnected and transboundary nature of the challenges to biodiversity conservation in the Arctic and beyond.