We examined the abundance and species richness of birds breeding in floodplain forests of the Upper Mississippi River from 1992 to 1994 to identify effects of a major flood in 1993 on the bird assemblage. Sixty-five study plots were divided into treatments and controls based on whether they were flooded in 1993. Among 84 species observed on all plots, 41 species decreased in abundance from 1992 to 1994, 13 species increased, and numbers of 5 species were unchanged. Sample sizes were inadequate to evaluate trends for 25 species. Species richness declined over the three-year period. The main effect "year" was significant in 20 of the 36 species tested. Cool, wet conditions may have contributed to poor reproductive success in 1993 and resulted in widespread declines in abundance during the year following the flood. Bird abundance increased on most unflooded plots in 1993, probably because birds were displaced from flooded plots. This pattern was most striking for Neotropical migrants, species preferring habitat edges, lower-canopy nesters, and species that forage in the air. We suggest that periodic major flooding maintains suitable floodplain habitat for Prothonotary Warblers (Protonotaria citrea) in the face of competition with House Wrens (Troglodytes aedon) for nest sites.
Additional publication details
|Publication Subtype||Journal Article|
|Title||Declines in abundance and species richness of birds following a major flood on the upper Mississippi River|
|Series title||The Auk|
|Publisher||American Ornithological Society|
|Contributing office(s)||Upper Midwest Environmental Sciences Center|
|Google Analytic Metrics||Metrics page|