Nest-site characterization and reproductive success of Mississippi kites in the Mississippi river floodplains
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The Mississippi kite (Ictinia mississippiensis) is considered rare in Missouri and occupies a habitat in the state that is being fragmented and converted into unsuitable habitat. To enhance our understanding of its habitat requirements and population status e examined the characteristics of Mississippi kite nesting habitat and reproductive success at 33 nest and random sites in 1990 and 26 sites in 1991 in the floodplain forests along the Mississippi River in southeastern Missouri. Forest tracts containing Mississippi kite nests (n = 7) were larger (x = 683 ha) than randomly sampled forest tracts (x = 7 ha, n = 7). Trees containing nests were taller than trees at random, and nests were positioned within the tree so that nests were above the surrounding forest canopy. Overstory and midstory tree diameter at breast height (dbh) were greater at nest sites than at random sites. Overstory tree density was less at nest sites than at random sites. Eastern cottonwood (Populus deltoides), American sycamore (Platanus occidentalis), and shagbark hickory (Carya ovata) were the most common trees at nest sites, whereas black willow (Salix nigra), green ash (Fraxinus pennsylvanica), and silver maple (Acer saccharium) were more frequent at random sites. The modified Mayfield nest-success estimate for 10 successful and 14 failed nests was 22%. We conclude that Mississippi kites select patches of atypically tall trees surrounding an even taller nest tree for nesting sites within the Mississippi River floodplain forests in southeastern Missouri. Preserving the larger forest tracts in the region, particularly those currently used as nest sitcs, and assuring the sustainability of the tallest growing trees like cottonwoods would have ong lasting, positive effects on Mississippi kite habitat in this region of its range.
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