#5 Alaskan wetlands and prairie potholes

Who are the major groups involved in wetland conservation in Alaska?

• First Nations and transboundary Indigenous groups

• Municipal, state, and federal governments

• Stewardship boards and councils

• Non-governmental organizations (e.g., Ducks Unlimited)

• Industry associations (often reluctantly)

How much of Alaska’s land area is covered by wetlands?

Approximately 40% of Alaska

• more than any state/ all of them combined

Why is wetland management in Alaska typically minimal?

active management is nearly impossible → b/c of immense wetland extent and remoteness

What is the goal for wetland management in Alaska?

protection rather than intervention

• maintaining existing wetland integrity

What types of wetlands occur in Alaska?

• bogs

• fens

• permafrost wetlands

• estuaries

• marshes

• boreal forest wetlands (swamps)

What are the two biggest threats to Alaskan wetlands?

• Resource extraction

• Climate change

How do NGOs like Ducks Unlimited contribute to Alaskan wetland conservation?

work to purchase or secure easements on wetlands to protect them from development

Prairie Pothole

• Small potholes (<1 acre in size) make up ~87% of wetlands in this region

  • Very small nodes of wetlands-> mosaic

What is the geographic extent of the Prairie Pothole Region?

Approximately 770,000 km² across the U.S. and Canada

What is the PPR mainly known as?

Great North American Duck Factory

• produces 50–80% of North America’s migratory ducks

The PPR also supports extensive bird diversity beyond ducks

How much of the remaining PPR wetlands are protected?

34% across the U.S. and Canada

How were prairie potholes formed?

By melting blocks of glacial ice left behind as glaciers receded

• buried ice melted→ depressions formed and filled with water

What is the primary water input and primary water loss mechanism for most prairie potholes?

• input→ Surface water from snowmelt

• output→ Evapotranspiration

  • especially in shallow potholes

Why is winter freezing a major ecological factor in the PPR?

water becomes unavailable during winter, forcing species to:

• Emigrate (leave)

• Enter dormancy

• Complete annual life cycles before winter

Freezing is one of the key reasons migratory waterfowl leave the region

Why is active wetland management rare in the Prairie Pothole Region?

• potholes are extremely numerous

• highly variable

• difficult to manage individually

Conservation focuses on protecting land rather than manipulating hydrology

What type of vegetation occurs inside prairie potholes?

• emergent plants

• tall grasses

• aquatic vegetation

depends on water depth and hydroperiod

What vegetation occurs between potholes?

Dense grassland vegetation

• remnants of historic tallgrass prairie

• has a diverse seed bank ready to germinate under varying conditions

What types of vegetation dominate permanently inundated potholes?

• Hard-stem bulrush

• Duckweeds/pondweeds

• Aquatic buttercups

What vegetation dominates drier potholes?

• Spikerushes

• Grasses

• Little to no woody vegetation

Why is the PPR critical for breeding waterfowl?

• Waterfowl spend summers there

• >50% of North American waterfowl are produced in this region

• 85% of all Mallards originate from the PPR

What major conservation tools are used to protect PPR waterfowl habitat?

• Land purchases

• Easements such as WRP (Wetland Reserve Program) and CRP

• Agreements with private landowners to protect wetlands

  • NGO-funded conservation programs

What amphibian patterns are seen in the PPR?

• Frogs → more associated with wetlands

• Toads → more associated with uplands

Overall amphibian diversity is not high but communities are fairly intact

Why are macroinvertebrates important in the PPR?

extremely diverse and serve as critical food sources for birds, fish, and amphibians

What are major threats to PPR habitat?

• Agricultural

  • Habitat loss

  • Chemical and nutrient runoff

• Climate change

  • Fire suppression

    • (interacts with climate change to promote woody encroachment)

• Slope is secondary

Why is “wetter” climate not necessarily good for potholes?

Pothole ecosystems rely on cyclical wet–dry transitions

• If wetlands stay too wet too long→ the natural hydrologic rhythm breaks

  • reducing its ecological function

Why is it difficult to recreate PPR wetlands artificially?

Because potholes are numerous, hydrologically variable, freeze seasonally, and rely heavily on snowmelt, they are extremely challenging to design or replicate

Besides Alaska and the PPR, what other major wetland regions exist in North America?

• Eastern seaboard

• Playa Lakes

• Great Lakes/St. Lawrence Basin