Pingo of the Arctic: A Unique Wildlife Habitat

Explanation: We are in one of the more remote places on the globe, in the far western corner of Alaska over Seward Peninsula and Bering Land Bridge National Preserve. Below us stretches endless tundra vistas uninhabited by humans and largely unstudied by researchers.

But behold, what is this odd domed structure that stretches for half a kilometer, with its own radial drainage pattern?

This is an Arctic landform called a pingo.

Pingos are formed from water being forced upward from the permafrost layer, where it freezes within the soil below the root zone as an expanding ice lens. Perhaps they form from frost compression and build upon themselves over time, erupting as a cone beneath the thin peat and lichen-covered soils of the Far North. Some sources suggest that they grow slowly, some continuing for up to a thousand years.

What also makes these landforms unique is that they seem to serve as relatively scarce habitat for a number of wildlife species, in part because pingos often host shrub and other plant growth in their drainage clefts. Pingos have been known to provide den sites for mink (Mustela vison), Arctic fox (Alopex lagopus), and other Arctic mammals, and habitat for masked shrews (Sorex cinereus).

The shrubs likely provide habitat for migrating birds and are used as occasionally nest sites by Emperor Geese (Chen canagicus), Cackling Canada Geese (Branta canadensis minima), and Black Brant (Branta bernicla nigricans).

Generally, the use of pingos by wildlife is poorly studied, and doubtless some surprises await discovery.

The word pingo comes from an Inupiaq name for the landform.

Information:
Anthony, R. M. 1997. Home ranges and movements of Arctic fox (Alopex lagopus) in western Alaska. Arctic 50(2):147-157.
Petersen, M. R. 1990. Nest-site selection by Emperor Geese and Cackling Canada Geese. Wilson Bulletin 102(3):413-426.

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