The Effects of the 2011 Missouri River Flood on the Populations of Breeding Grassland Birds at Desoto and Boyer Chute National Wildlife Refuges

Download or read book The Effects of the 2011 Missouri River Flood on the Populations of Breeding Grassland Birds at Desoto and Boyer Chute National Wildlife Refuges written by Jason E. Andersen and published by . This book was released on 2015 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Missouri River flood of 2011 has had a profound impact on the habitat at DeSoto and Boyer Chute National Wildlife Refuges by altering the composition and structure of the vegetation that grassland birds use for breeding. Grasslands at the refuges have been heavily impacted by sand and silt deposition caused by receding floodwaters from which several diverse and novel plant communities have emerged. My research investigated how changes in vegetation affected the bird communities at the refuges. My research showed that areas which were grasslands before the flooding in 2011 now have higher forb densities and higher occurrence of shrubs and cottonwoods in post-flood years and decreased relative cover of grass compared to forbs and shrubs. Populations of generalist bird species have increased since the flood, while most populations of specialist grassland bird species have experienced decreases. With these changes in species abundances, community composition has shifted from favoring grassland specialist species to instead favoring generalist species. After the flood, Dickcissels abundance declined on sites when cottonwood sapling density exceeded 1.75 plants/m2 and as cottonwood sapling height increased while Grasshopper Sparrow occurrence declined on sites with grass heights above 60 cm.