Key Findings

Most species showed contrasting trends between different populations/flyways. This variation complicates drawing broad conclusions, except that since most bird species leave the Arctic in winter they are affected by a wider range of drivers and geographical scales than other FECs. A meta-view on 88 terrestrial Arctic tundra birds shows that:

Many populations are stable or increasing; for some populations (mainly geese) the increase may be effects of global change – including land use outside the Arctic – allowing populations to increase beyond levels likely under undisturbed conditions.
Variability across FECs is high, with more than half of all wader species declining and nearly half of all geese increasing. Variability across flyways is also high, even within FECs. For example, 88% of waders are declining in the East Asian - Australasian Flyway, compared with 70% of wader populations stable or increasing in the African - Eurasian Flyway.
For more than half of all species, there are reasons for concern for some flyway populations—57% of all species had at least one population in decline and for 21% of the species all populations were declining.
Trends are unknown for at some populations in a quarter of species—mostly in the Central Asian Flyway; for the remaining species, the quality of trends information is highly variable.
Ten species are ranked in the global ‘threatened’ categories according to IUCN criteria— including two species as Critically Endangered.
Populations of both ptarmigan species showed both positive and negative trends with no clear links to geographical regions, and most populations displayed short and long population cycles linked to cycles in other herbivore species or driven by predation.
Among the predators, breeding parameters of gyrfalcons, snowy owls and rough-legged buzzards are linked to prey with cyclic abundance like ptarmigan and rodents—for both falcon species, it is likely that breeding populations in the Arctic are relatively stable.
Climate change affects different species and populations very differently with no consistent pattern—examples include breeding failure in ground-nesting waders in years of late snow melt, reduced breeding success in peregrine falcons due to increased frequency of heavy rain events and massive blackfly outbreaks in warm spells, and possible range expansion of peregrine falcons due to longer summer season in high Arctic. Although evidence is diverse, phenological mismatches are considered among the leading potential stressors of wildlife populations arising from climate change. The accelerated rate of warming at high latitudes advances spring, causing arthropod activity to start and peak, potentially resulting in a mismatch in phenology between long-distance migrant bird populations and their food resources in the Arctic breeding grounds.
Main drivers of population change—positive as well as negative—outside the Arctic include harvesting and intensified land management (including agricultural practises, land reclamation and urban development).

Monitoring Advice

Most bird species are difficult to monitor and attribute change due to the large spatial extent of their breeding habitats and multiple threats throughout flyways. Current monitoring is uneven and inadequate. The START reports on herbivores, insectivores, carnivores, and omnivores.

Sustaining long-term monitoring projects is the best opportunity to track changes in FECs and drivers of those changes.
Expand monitoring of species and populations with unknown or uncertain trends such as waders in the Central Asian Flyway and East Asian–Australasian Flyway (under the Arctic Migratory Birds Initiative).
Improve monitoring coverage of the high Arctic and other areas with poor spatial coverage (i.e., Canadian Arctic Archipelago, Greenland, and eastern Russia), including staging and wintering areas within and outside the Arctic.
Adopt new and emerging monitoring technologies, including various tagging devices (for the study of distribution and migration, and identification of critical stopover and wintering sites), bioacoustics (for abundance and diversity sampling), and satellite data (for colony monitoring).
Enhance coordination within and among Arctic and non-Arctic states to improve data collection on migratory species and critical site identification across species’ ranges.
Harmonize long-term studies to improve the reliability of status and trends assessments, ability to report on FEC attributes (e.g., phenology), and possible effects of environmental change, including risks of phenological mismatch.
Use research stations as platforms to increase data coordination, sampling, and analyses, of FECs and drivers, and ensure standardized bird monitoring is part of station mandates where lacking.
Strengthen linkages with AMAP to improve contaminant monitoring at different trophic levels and facilitate cooperation on isotope and genetic studies.