Using river flow management to improve wetland habitat quality for waterfowl on the Mississippi River, USA

  • Published source details Dugger B.D. & Feddersen J.C. (2009) Using river flow management to improve wetland habitat quality for waterfowl on the Mississippi River, USA. Wildfowl, 59, 62-74.


This study is summarised as evidence for the following.

Action Category

Actively manage water level: freshwater marshes

Action Link
Marsh and Swamp Conservation
  1. Actively manage water level: freshwater marshes

    A study in 1999–2001 of a section of the Mississippi River in Illinois/Missouri, USA (Dugger & Feddersen 2009) reported that when the water level was successfully lowered for 30 days, herbaceous plant species colonized exposed parts of the floodplain. In 1999 and 2001, fifteen to seventeen plant taxa were recorded on the exposed floodplain. The most common taxa were sedges Cyperus spp. (occurring in 69–77% of surveyed quadrats), barnyard grasses Echinochloa spp. (53–80%) and knotweeds Polygonum spp. (28–93%). In 2000, low water levels could not be maintained for a continuous 30 day period. Vegetation that had germinated on exposed soils was killed by the floodwaters. Methods: Each spring between 1994 and 2001, downstream dam gates were opened to lower the water level in the focal section of the Mississippi River. The aim was to expose floodplain soils and allow certain herb species to germinate. Each year between 1999 and 2001, plant species and their cover were surveyed in 55–65 quadrats on the floodplain, approximately three weeks after initial exposure.

    (Summarised by: Nigel Taylor)

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