- Across all characteristic species, the overall indicator has changed little because it combines both dramatic increases in waterfowl, primarily geese, and steep declines in shorebirds. The annual variability in the indicators reflects both true annual fluctuations in bird populations in this highly variable environment, and also uncertainty that comes from challenges in monitoring Arctic species.
- Shorebirds that nest in the Arctic are declining sharply. The biggest threats are habitat loss and degradation along migratory routes and in wintering areas, but climate change may be reducing their breeding success.
- Several goose populations have increased dramatically due largely to abundant winter food sources from agriculture; these populations are now causing serious damage to Arctic wetlands and tundra through over-grazing.
- Climate change is already affecting Arctic ecosystems and is projected to change at rates that will exceed the ability of some Arctic bird species to adapt.
The population status of many Arctic birds is poorly known because the remoteness, vast area and challenging weather conditions in the Arctic make monitoring difficult. Information for many species depends on counts made during migration or on their wintering grounds, but these counts can be imprecise and may be affected by shifts in wintering distribution or migration behaviour.
Among species for which data are available, the overall indicator appears to have changed little, but this reflects a combination of large increases in some groups and large declines in others.
Most goose and swan populations have increased dramatically, due partly to extra food sources in agricultural areas on their migration routes and wintering areas.
Snowy Owl populations have declined by more than
half, possibly due to changes in lemming populations
associated with climate change. (photo: Ducks
Too much of a good thing? Snow Goose popu-
lations have increased by more than 300% and
are degrading coastal salt marshes through intense
foraging. (photo: May Haga)
Increased natural resource exploration and extraction—such as expansion of energy and mining activities and associated infrastructure—disturb nesting birds, destroy sensitive habitats and increase the risk of spills or other environmental contamination.
Many Arctic-nesting birds migrate long distances and are particularly vulnerable to threats beyond Canada’s borders. Hazards include extreme weather, hunting, pesticides, changes in food availability and habitat loss at migration stopover sites and wintering areas.
Development in the Arctic must be carefully
managed to avoid ecosystem damage. (photo:
Government of NWT)
Maintaining stringent environmental assessments for development projects in the Arctic and appropriate mitigation measures will reduce risks to birds.
Protection of key stopover habitats and food sources along migration routes, both inside and outside of Canada, and regulation of hunting in Caribbean and South and Central American wintering areas, are necessary to help improve survival for Arctic-nesting shorebirds.
Endangered Red Knots migrate through Delaware
Bay where they feed on the eggs of horseshoe
crabs to fuel their spring migration. Overfishing
of the crabs has been a major factor leading
to declines in this species. (photo:May Haga)
Challenges for long-distance migratory shorebirds
Arctic shorebird populations have declined by 60% overall and 10 species are in severe decline. Similar patterns are evident for shorebirds nesting elsewhere in Canada.
Migrating from one end of the world to the other, shorebirds depend on a complex network of wetland and upland habitats, and are vulnerable to habitat loss at any stage of their journey.
Arctic breeding Whimbrel are threatened
by hunting in the Caribbean. (photo: May Haga)
Many species of shorebirds concentrate in large numbers at key feeding and resting sites along their migration routes, both in Canada and internationally. Loss or degradation of any one of these sites can lead to dramatic declines in their populations. Shorebirds are also affected by habitat loss and other threats on their wintering areas, such as development that is reducing and degrading coastal habitats in the Caribbean and Central and South America, and agricultural expansion and intensification that is affecting open grassland habitat.
Monitoring shorebirds in the Arctic taiga
provides valuable information on distribution
and trends but is logistically challenging and
expensive, requiring helicopters to access
sampling areas. (photo: Charles Francis)
Monitoring shorebird populations presents particular challenges. Most current monitoring data come from migration stopover sites, but may be biased by changes in stopover behaviour. A major international effort, the Program for Regional and International Shorebird Monitoring (PRISM) is now underway to improve understanding of population trends and causes of declines of shorebirds involving surveys in the Arctic, on migration and in southern wintering areas.