Wetland Drying and WildlifeBrad Griffith & Jennifer Roach

U.S. Geological Survey and University of Alaska Fairbanks

Photo by May-Le Ng

Annual Rates of Change in Lake Size

1985-200923,000 lakes:89% Stable/Fluctuating8% Drying3% Increasing

YUKON FLATS: CENTRALDecreasing Trend

YUKON FLATS: WESTIncreasing Trend

YUKON FLATS: EASTNegligible Trend

Clustering of Increasing and Decreasing lakes

Roach et al. 2013 Global Change Biol. 19: 2276-2284

Among-Lake Heterogeneity

Shrinking Lake

Expanding Lake

8/5/1952 8/30/2008

Why is this Happening?

• Drainage• Lack of recharge• Lakes more likely to dry if:• Within a burned area• On coarse, well-drained soils• Farther from rivers and streams

• Implies:• Permafrost degradation

What are Implications for Wildlife?

Photo by May-Le Ng

Waterfowl Species RichnessBased on current Landscape Metrics

Lake size most influential

in 2010

1986 2050

Roach & Griffith 2015

CENTRAL

WEST

EAST

+2%

-26%

-4%

Species Richness

Projections: 1986-2050

• 11% decline in average number of species per lake

• Heterogeneity among regions and lakes• Regions: -26% to +4%• Lakes: -70% to +214%

• Most vulnerable species are the rare ones• on the edges of their ranges

Implications:• Alaskan National Wildlife Refuges –

• 16 refuges; 77 million acres; 81% of entire National Wildlife Refuge System

• These Refuges support internationally migratory waterfowl• These waterfowl provide ecosystem services at multiple scales

• Climate change in Alaska is expressed throughout North America

50%

25%10%

10%