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Loss of Wetlands: How Are Bird Communities Affected?

Robert Fletcher


Wetland bird populations are stressed due to:

  • devastating habitat loss throughout the world
  • human intervention, such as agricultural expansion
  • other factors, such as invasive species and climate change
  • lack of research data to improve management practices

October 2003

Wetland habitat loss is substantial in the U.S.

Habitat loss has occurred at devastating rates throughout the world over the past two centuries. Yet these losses are not all equal, and some environments have been affected more than others. Wetland habitat in North America provides one such example. Throughout much of the United States, wetland habitat loss has been substantial:

A wading bird, a Great Blue Heron, in the wetlands of the Myakka River basin. Florida. Photographer: Gary Burdette.

Over 20 states have lost 50% or more of their original wetlands.
95% of today’s wetlands are freshwater.
New Zealand has lost over 90% of its original wetlands.
  • Between 1780’s and 1980’s, the lower 48 states have lost 53% of the original wetland habitat, or about 104 million acres.1

  • Twenty-two states have lost 50% or more of their original wetlands, with California losing the largest percentage (91%) and Florida losing the most acreage (9.3 million acres).1

  • Most recent losses over the past two decades have been primarily due to agriculture and urban development.2

  • Most recent losses have been in freshwater wetlands (98%), and 95% of the remaining wetlands are freshwater (as opposed to coastal marshes).2

Robert Fletcher, Ph.D., is a Research Associate at the University of Montana. He received his doctorate from Iowa State University in Ecology and Evolutionary Biology in 2003. His interests include habitat fragmentation and habitat restoration, population biology, landscape ecology, and statistics. He has done research throughout much of the United States, including Iowa, Florida, and Colorado, focusing on conservation issues of grassland, wetland, and riparian bird communities.

Update 6/26/09: In 2007, Dr. Fletcher accepted a position at the University of Florida, Gainesville, where he currently runs the Fletcher Lab.

Loss of Wetlands: How Are Bird Communities Affected?

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Wetlands International

The site provides information regarding the status of wetlands throughout the world, including info on global waterbird issues.

Smithsonian Migratory Bird Center

The Smithsonian Migratory Bird Center has a number of free fact sheets related to migratory birds. The publications are available in both English and Spanish.

U.S. Wetlands Inventory

“The National Wetlands Inventory (NWI) of the U.S. Fish & Wildlife Service produces information on the characteristics, extent, and status of the Nation’s wetlands and deepwater habitats,” including useful maps displaying wetland locations.

Effects of management practices on wetland birds

This site has links to a variety of North American wetland bird species. Each link contains a thorough review of issues regarding management and wetland birds.

Patuxent Wildlife Research Center

This Center is a leader in wildlife research and this site provides information for both the novice and the professional, including links to a variety of info on both birds and wetlands.

Bird identification on the Web

This site has links to information on North American birds. Each link includes “photographs, songs, videos, identification tips, maps, and life history information.”

Avian Science Center

On-line source to a variety of issues regarding birds and their habitats. In addition, it contains links to sites where you can help participate in projects related to birds.

Wetlands Institute

The Wetlands Institute of Stone Harbor, NJ is “The Natural Place to Have Fun Learning!” The organization promotes the conservation and preservation of coastal ecosystems by providing a fun and educational experience for families, school groups, and vacationers of all ages.

Citizen scientists

At the Cornell Lab of Ornithology, you can participate in a variety of projects related to birds in North America, including the backyard bird count.

The Audubon Society: taking action

This site contains information regarding current issues in bird conservation. It contains links for contacting lawmakers on conservation issues that impact birds, wildlife, and the environment.

Classroom Resources

Wetland Welfare

In this lesson, students research wetlands in the United States and create visual aids for use in oral presentations that make recommendations on preserving or restoring wetland welfare.

  1. Dahl, T. E. 1990. “Wetland losses in the United States: 1780’s to 1980’s.” U.S. Fish and Wildlife Service, Washington, DC. 13 p.
  2. Dahl, T. E. 2000. “Status and trends of wetlands in the conterminous United States 1986 to 1997.” U.S. Fish and Wildlife Service, Washington, DC. 82 p.
  3. Brinson, M. M., and A. I. Malvarez. 2002. “Temperate freshwater wetlands: types, status, and threats.” Environmental Conservation 29:115-133.
  4. Tzoumis, K. A. 1998. “Wetland policymaking in the U. S. Congress from 1789-1995.” Wetlands 18:447-459.
  5. De Laney, T. A. 1995. “Benefits to downstream flood attenuation and water quality as a result of constructed wetlands in agricultural landscapes.” Journal of Soil and Water Conservation 50: 620-626.
  6. Howard-Williams, C. 1985. “Cycling and retention of nitrogen and phosphorus in wetlands: theoretical and applied perspective.” Freshwater Biology 15:391-431.
  7. Raisin, G. W., and D. S. Mitchell. 1995. “The use of wetlands for the control of non-point source pollution.” Water Science and Technology 32:177-186.
  8. Chabreck, R. A. 1988. Coastal marshes: ecology and wildlife management. University of Minnesota Press, Minneapolis, MN.
  9. van der Valk, A. G., editor. 1989. Northern Prairie Wetlands. Iowa State University Press, Ames, IA.
  10. Wiebe, K. D., A. Tegen, and B. Kuhn. 1995. “Property rights, partial interests, and the evolving federal role in wetlands conversion and conservation.” Journal of Soil and Water Conservation 50:627-629.
  11. Igl, L. D., and D. H. Johnson.1994. “Changes in breeding bird populations in North Dakota: 1967 to 1992-93.” Auk 114:74-92.
  12. Fletcher, R. J., Jr., and R. R. Koford. 2003. “Changes in breeding bird populations with habitat restoration in northern Iowa.” American Midland Naturalist 150:83-94.
  13. Johnson, D. H. 2001. Habitat fragmentation effects on birds in grasslands and wetlands: a critique of our knowledge. Great Plains Research 11:211-231.
  14. Whitt, M. B., H. H. Prince, and R. R. Cox, Jr. 1999. “Avian use of purple loosestrife dominated habitat relative to other vegetation types in a Lake Huron wetland complex.” Wilson Bulletin 111:105-114.
  15. Poiani, K. A., and W. C. Johnson. 1991. “Global warming and prairie wetlands: potential consequences for waterfowl habitat.” Bioscience 41:611-618.
  16. Weller, M. W. 1999.Wetland birds: habitat resources and conservation implications.Cambridge University Press, Cambridge, UK.
  17. Bethke, R. W., and T. D. Nudds. 1995. “Effects of climate change and lands use on duck abundance in Canadian prairie-parklands.” Ecological Applications 5:588-600.
  18. Naugle, D. E., K. F. Higgins, S. M. Nusser, and W. C. Johnson. 1999. “Scale-dependent habitat use in three species of prairie wetland birds.” Landscape Ecology 14:267-276.
  19. Benoit, L. K., and R. A. Askins. 2002. “Relationship between habitat area and the distribution of tidal marsh birds.” Wilson Bulletin 114:314-323.
  20. Whited, D., S. Galatowitsch, J. R. Tester, K. Schik, R. Lehtinen, J. Husveth. 2000. “The importance of local and regional factors in predicting effective conservation planning strategies for wetland bird communities in agricultural and urban landscapes.” Landscape and Urban Planning 49:49-65.
  21. Fairbairn, S. E., and J. J. Dinsmore. 2001. “Local and landscape-level influences on wetland bird communities of the Prairie Pothole Region of Iowa, USA.” Wetlands 21:41-47.
  22. Picman, J., M. L. Milks, and M. Leptich. 1993. “Patterns of predation on passerine nests in marshes: effects of water depth and distance from edge.” Auk 110:89-94.
  23. Phillips, M. L., W. R. Clark, M. A. Sovada, D. J. Horn, R. R. Koford, and R. J. Greenwood. 2003. “Predator selection of prairie landscape features and its relation to duck nest success.” Journal of Wildlife Management 67:104-114.
  24. Seabloom, E. W., and A. G. van der Valk. 2003. “Plant diversity, composition, and invasion of restored and natural prairie pothole wetlands: implications for restoration.” Wetlands 23:1-12.
  25. Ratti, J. T., A. M. Rocklage, J. H. Giudice, E. O. Garton, and D. P. Golner. 2001. “Comparison of avian communities on restored and natural wetlands in North and South Dakota.” Journal of Wildlife Management 65:676-684.


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