Influence of wetland age on bird use of restored wetlands in Iowa

  • Published source details VanRees-Siewert K.L. & Dinsmore J.J. (1996) Influence of wetland age on bird use of restored wetlands in Iowa. Wetlands, 16, 577-582.


This study is summarised as evidence for the following.

Action Category

Raise water level to restore/create freshwater marshes from other land uses

Action Link
Marsh and Swamp Conservation
  1. Raise water level to restore/create freshwater marshes from other land uses

    A replicated study in 1991–1992 of rewetted prairie pothole marshes in Iowa, USA (VanRees-Siewert & Dinsmore 1996) reported that they developed 63% coverage of emergent vegetation within four years. For twelve 1-year-old marshes, the average area covered by emergent vegetation stands was only 20%. Emergent vegetation was clustered around the pothole margin in 10 of the marshes. Coverage of emergent vegetation increased with wetland age, to an average of 63% across six 4-year-old marshes. Emergent vegetation was distributed across the whole pothole in three of six cases, clustered around the margin in two cases and clustered in the centre in one case. Methods: In July 1991 and 1992, emergent vegetation stands were mapped in 24 rewetted prairie pothole marshes (<6 ha; drained and farmed for >20 years before rewetting; details of rewetting not reported). The potholes were surveyed one, two, three or four years after rewetting. Sixteen potholes were surveyed in both years. Eight potholes were surveyed in 1992 only. This summary takes some methodological details from VanRees-Siewert (1993).

    Additional Reference: VanRees-Siewert K.L. (1993) The influence of wetland age on bird and aquatic macroinvertebrate use of restored Iowa wetlands. M.S. Thesis, Iowa State University, Ames, IA, USA.

    (Summarised by: Nigel Taylor)

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