Images

Yellow-billed Loon on a lake in the northern area of Alaska.

Degrading ice wedges on the Ikpikpuk River Delta on the North Slope of Alaska.

Along the northwestern shoreline of Driftwood Bay, Umnak Island, Alaska, the Cabin Flat study site (left) occupies a coastal lowland that backs a vegetated, emergent beach. Much of Driftwood Bay’s shoreline is flanked by sea cliffs over 50 m high and an extensive bedrock platform (right) in the intertidal zone.

A geologist stands on a drift log stranded 23 m above mean tide level, overlooking the Cabin Flat study site and Driftwood Bay, Umnak Island, Alaska.

Geologists camped near an upland lake about 0.5 km from the shore of Driftwood Bay, Umnak Island, Alaska. Vsevidof Volcano in the background.

Sarah Schoen, Mayumi Arimitsu, and Brielle Heflin pulling in a modified herring trawl on the R/V Alaskan Gyre in Prince William Sound, Alaska.

Northern pike captured from an Arctic Coastal Plain lake. Predatory fish, like this northern pike, occupied only lakes with strong, permanent channel connections. Permanent channel connections provide movement corridors that fish use to swim between summer feeding areas and winter refuges.

Tundra lakes, Selawik National Wildlife Refuge

Hardwood patch on high ground, Selawik National Wildlife Refuge.  Dominant ecotypes include Upland Moist Dwarf Birch-Ericaceous-Willow Low Shrub, upland Organic-rich Moist Acidic Dwarf Birch-Tussock Shrub, and Upland Rocky-Loamy Moist Circumacidic Alder-Willow Tall Shrub.

Flooded thermokarst area with high escarpment, Bering Land Bridge National Preserve, Seward Peninsula.

Thermokarst lake and river meanders, Seward Peninsula.  Dominant ecotypes include Lowland Lake, Lowland Organic-rich Wet Circumacidic Willow Low Shrub, Upland Organic-rich Moist Acidic Dwarf Birch-Tussock Shrub, and Upland Rocky-Loamy Moist Alkaline Sedge-Dryas Meadow. 

Coastal brackish marsh, Bering Land Bridge National Preserve, Seward Peninsula

Coastal erosion, Baldwin Peninsula.

Patterned ground along the Noatak River, Noatak National Preserve.  Dominant ecotypes include Riverine Loamy Wet Circumacidic Wet Sedge Meadow, Riverine Loamy Moist Circumacidic Birch-Willow Low Shrub, Riverine Gravelly Moist Circumalkaline Barrens, and Riverine Gravelly Dry Alkaline Dryas Dwarf Shrub. 

Recent tundra fire scar, Noatak National Preserve.

Coastal river sand bar, Bering Land Bridge National Preserve, Seward Peninsula.  Dominant ecotypes include Coastal Barrens, Coastal Loamy Wet Brackish Sedge-Grass Meadow, and Lowland Moist Sedge-Dryas Meadow. 

“Drunken forest” of white spruce from permafrost melt along thermokarst lake shoreline, Selawik National Wildlife Refuge. 

Recovered river meanders along Kobuk River, Kobuk Valley National Park.  Dominant ecotypes include Riverine Water, Riverine Loamy Moist Alder or Willow Tall Shrub, Riverine Gravelly-loamy Moist Circumalkaline White Spruce-Willow Forest, and Riverine Loamy Wet Circumacidic Wet Sedge Meadow. 

Coastal shorelines, Cape Espenberg, Bering Land Bridge National Preserve, Seward Peninsula

Thermokarst lake, Seward Peninsula.

Partially drained thermokarst lake with residual pool and patterned ground , Bering Land Bridge National Preserve, Seward Peninsula.