BIRD DISTRIBUTIONS AND FOREST ZONATION IN A BOTTOMLAND HARDWOOD WETLAND

During spring of 1988 and winter of 1988-89, we sampled songbird popul ations and habitat characteristics along two belt transects extending across the broad, forested floodplain of the Cache River, Arkansas, US A. Objectives were to compare avian abundance and species richness amo ng floodplain forest zones and to investigate bird species distributio ns in relation to the wetness gradient. Forest zones differed in struc ture, flooding regime, and use by birds. The tupelo/baldcypress zone, in particular, provided habitat unlike that in the higher oak-dominate d zones and supported a number of bird species that were much less abu ndant elsewhere. Distributions of chimney swifts (Chaetura pelagica), prothonotary warblers (Protonotaria citrea), and great crested flycatc hers (Myiarchus crinitus) were skewed toward wetter sites, whereas sum mer tanagers (Piranga rubra), red-eyed vireos (Vireo olivaceus), and o thers were skewed toward drier sites.