Wood duck nest sites in bottomland hardwood forests of Mississippi

We studied the occurrence of natural cavities suitable for wood duck (Aix sponsa) nest sites in mature bottomland hardwood forests on Noxubee National Wildlife Refuge (NNWR) and Delta National Forest (DNF), Mississippi in 1985 and 1986. We found 0.19 ± 0.09 (SE) and 0.23 ± 0.13 suitable cavities/ha on NNWR and DNF, respectively. Sycamore (Platanus occidentalis) and beech (Fagus grandifolia) trees contained 60% of the suitable cavities on NNWR, but composed only 2.6% of the available trees. Cavity rates on the 2 areas were among the lowest reported for mature forests in North America. The paucity of suitable cavities suggests nest box programs are more important to maintain breeding populations of wood ducks in riparian bottomland forests of the lower Mississippi Valley and the Gulf Coastal Plain than has recently been reported along the northern edge of their range.