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Magnitude and rates of lake drying in wetlands on National Wildlife Refuges in AK


December 2005 - January 2011


Refuge wetlands support millions of waterfowl and shorebirds and produce hundreds of thousands of ducklings, goslings and shorebirds annually that have been recovered in nearly all states, 8 Canadian provinces and other countries. Climate change could alter the fundamental nature of Alaskan refuges. Riordan (2005) found significant loss of lakes in wetlands on several Interior Alaska refuges; however, the geographic scope and magnitude of lake losses in Alaskan refuges have not been described. Magnitude and rates of lake drying have not been described across an E-W gradient (e.g., Yukon Delta - Tetlin NWRs) or N-S gradient (e.g., Izembek - Arctic NWRs). Finally, understanding the amount and rate of lake losses in wetlands across Alaska refuges will be essential to predicting potential effects on the distribution, abundance and productivity of waterbirds, particularly ducks and geese. Crucial proactive first steps toward understanding this potential problem are to: 1) fully characterize the heterogeneity in the magnitude and rate of lake drying in Alaskan Refuge wetlands, 2) identify differential characteristics of lakes that are drying and those that are not, 3) estimate whether change in total surface water area in wetlands (open and closed-basin lakes) occurs at the same rate of decline as for closed-basin lakes, and 4) assess the influence of fire on lake drying in refuge wetlands.
1. Complete a statewide estimate of the heterogeneity in closed-basin lake drying initiated by Riordan (2005)
2. Estimate the rate of change in total surface water and compare this to the rates of change documented for closed-basin lakes in National Wildlife Refuges during the same time period, 1950-2002 (see Riordan 2005).
3. Document factors associated with variability in the magnitude and rate of drying among closed-basin lakes in study areas in National Wildlife Refuges (see Riordan 2005).
Document the effects of wildfire on open water dynamics in refuge wetlands.

Research Products and Activities

Peer Reviewed Publications

  • Roach, J., B. Griffith, D. Verbyla, and J. Jones. 2011. Mechanisms influencing changes in lake area in the Alaska boreal forest. Global Change Biology 17:2567-2583. doi: 10.1111/j.1365-2486.2011.02446.x Abstract |  Download  |  Publisher Website | 
  • Roach, J.K., B. Griffith, and D. Verbyla. 2012. Comparison of three methods for long-term monitoring of boreal lake area using Landsat TM and ETM+ imagery. Canadian Journal of Remote Sensing 38(4): 427-440. Abstract |  Publisher Website | 

Current Staff

Federal Staff: 95

Masters Students: 239

Phd Students: 142

Post Docs: 53

University Staff: 240

5 Year Summary

Students graduated: 701

Scientific Publications: 1936

Presentations: 4260



Funding Agencies

  • Science Support Partnership


Cooperative Research Units Program Headquarters Cooperators

  1. U.S. Geological Survey