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Although North American wood ducks (Aix sponsa) are well‐studied throughout their range, researchers know little about demographic and environmental factors influencing survival of ducklings and broods, which is necessary information for population management. We studied radiomarked female and duckling wood ducks that used nest boxes and palustrine wetlands at Noxubee National Wildlife Refuge (NNWR) in Mississippi, USA, in 1996–1999, and riverine wetlands of the Tennessee‐Tombigbee Rivers and Waterway (TTRW) system in Alabama in 1998–1999. We estimated survival of ducklings and broods and evaluated potentially important predictors of duckling survival, including age and body mass of brood‐rearing females, hatch date of ducklings, duckling mass, brood size at nest departure, inter‐day travel distance by ducklings, site and habitat use, and daily minimum air temperature and precipitation. At NNWR, survival of 300 radiomarked ducklings ranged from 0.15 (95% CI = 0.04‐0.27) to 0.24 (95% CI = 0.13‐0.38) and was 0.21 (95% CI = 0.15‐0.28) for 1996–1999. Our overall estimate of brood survival was 0.64 (n = 91; 95% CI = 0.54‐0.73). At TTRW, survival of 129 radiomarked ducklings was 0.29 in 1998 (95% CI = 0.20‐0.41) and 1999 (95% CI = 0.13‐0.45) and was 0.29 (95% CI = 0.20‐0.40) for 1998–1999. Our overall estimate of brood survival was 0.71 (n = 38; 95% CI = 0.56‐0.85). At NNWR, models that included all predictor variables best explained variation in duckling survival. Akaike weight (wi) for the best model was 0.81, suggesting it was superior to other models (<0.01 < wi < 0.18). We detected 4 competing models for duckling survival at TTRW. Inter‐day distance traveled by ducklings was important as this variable appeared in all 4 models; duckling survival was positively related to this variable. Patterns of habitat‐related survival were similar at both study areas. Ducklings in broods that used scrub‐shrub habitats disjunct from wetlands containing aggregations of nest boxes had greater survival probabilities than birds remaining in wetlands with such nest structures. Managers may increase local wood duck recruitment by promoting availability of suitable brood habitats (e.g., scrub‐shrub wetlands) without aggregations of nest boxes that may attract predators and by dispersing nest boxes amid or adjacent to these habitats. We did not determine an optimal density of nest boxes relative to local or regional population goals, which remains important research and conservation needs.

Many studies have been conducted on the ecology of raccoons (Procyon lotor), while few have examined raccoon den‐site selection, particularly in agricultural and prairie landscapes. Furthermore, no studies have examined selection of den sites at multiple spatial scales. We examined den‐site selection for 48 raccoons during 1997–1999 in an agricultural landscape in the Black Prairie physiographic region of east‐central Mississippi, USA. Den types selected by raccoons differed by gender and season. Females used more cavity dens during young rearing, whereas males selected ground dens and brush piles. We found that den sites were located closer to crop fields, roads, and macrohabitat edges than random points. At the landscape level, den sites were associated positively with woody patch size, amounts of woody and grass edge, number of available patches of crop fields, and available area of lakes and ponds. Composition of habitats around den sites differed from composition of habitats within home ranges, and this difference also was noted by gender. Female raccoons selected crop fields, whereas males selected lakes/ponds relative to composition of habitats within their respective home ranges. Our results indicate the importance of tree cavities to females during young rearing, particularly on prairie landscapes. Furthermore, our findings suggest that on prairie landscapes, availability of foraging habitat and water may influence den‐site selection. We suggest that raccoons select den sites based on a perceived arrangement of required resources and that landscape configuration is important in the den‐selection process. Additionally, our findings offer evidence that managers may selectively remove den sites as a nonlethal means of managing predation by raccoons.

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