The Food Security Act of 1985 contained provisions that affected wildlife conservation nationwide. Two provisions that most benefited waterfowl populations in the Prairie Pothole Region (PPR) were the Conservation Reserve Program (CRP) and “Swampbuster” (wetland conservation). Permanent cover established under the CRP provides attractive nesting habitat for upland‐nesting ducks that is more secure than other major habitats. Swampbuster has prevented drainage of wetlands vital to breeding duck pairs. In 2007 many CRP contracts will expire. Deliberations will begin in late 2006 regarding the next Farm Bill. The United States Department of Agriculture needs sound biological information and scientific analyses to help establish wildlife priorities in the Farm Bill. We used data from breeding duck population and wetland habitat surveys to develop models for 5 species of upland‐nesting ducks and applied these models to >2.6 million wetlands in a digital database for the PPR in North and South Dakota, USA. We used geographic information systems techniques to identify locations in the PPR where CRP cover would be accessible to the greatest number of nesting hens. We then summarized distribution of current CRP contracts relative to distribution of upland‐breeding ducks. We also used our models to predict change in the breeding duck population (landscape carrying capacity) that might occur if certain wetlands were exempt from the Swampbuster provision. Our analyses showed that 75% of CRP contracts as of July 2005 were in areas accessible to high or medium numbers of breeding ducks and 25% were in areas of low populations. We suggest a method to prioritize CRP extensions and reenrollment of current contracts or target new contracts to maintain or increase duck production. Additionally, our models suggested that if the Swampbuster provision were removed from future Farm Bills and protected wetland were drained, this area of the PPR could experience a 37% decline in the waterfowl populations we studied.

American agriculture has provided abundant high‐energy foods for migratory and resident wildlife populations since the onset of modern wildlife management. Responding to anecdotal evidence that corn residues are declining in cropland, we remeasured waste corn postharvest in the Central Platte River Valley (CPRV) of Nebraska during 1997 and 1998 to compare with 1978. Post‐harvest waste corn averaged 2.6% and 1.8% of yield in 1997 and 1998, respectively. After accounting for a 20% increase in yield, waste corn in 1997 and 1998 was reduced 24% and 47% from 1978. We also evaluated use of soybeans by spring‐staging sandhill cranes (Grus canadensis) and waterfowl during spring 1998 and 1999. Despite being widely available in the CPRV, soybeans did not occur in esophageal contents of sandhill cranes (n=174), northern pintails (Anas acuta, n = 139), greater white‐fronted geese (Anser albifrons, n = 198), or lesser snow geese (Chen caerulescens, n=208) collected with food in their esophagi. Lack of soybean consumption by cranes and waterfowl in Nebraska in early spring builds upon previously published findings, suggesting that soybeans are poorly suited for meeting nutrient needs of wildlife requiring a high‐energy diet. Given evidence that high‐energy food and numerous populations of seed‐eating species found on farmland are declining, and the enormous potential risk to game and nongame wildlife populations if high‐energy foods were to become scarce, a comprehensive research effort to study the problem appears warranted. Provisions under the Conservation Security subtitle of The Farm Security and Rural Investment Act of 2002 offer a potential mechanism to encourage producers to manage cropland in ways that would replace part of the high‐energy foods that have been lost to increasing efficiency of production agriculture.

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We monitored evening flights of female Northern Pintails (Anas acuta) from Lacassine National Wildlife Refuge (NWR) in southwestern Louisiana during winters of 1991-1992 and 1992-1993. We analyzed the influence of female age, winter, and date within wintering period on three flight parameters: distance, duration, and departure time. Flight distance and duration increased with date within wintering period, and age differences in flight distance and duration were not consistent between winters. Females departed 12 min later, on average, on clear, moonlit evenings than on overcast, moonless evenings, and 4 min later when winds were light rather than heavy. After controlling for variation due to environmental conditions, immature females departed Lacassine NWR 1.3 min earlier, on average, than did adults. Flight parameters of females did not differ between hunting and non-hunting time periods. Estimated daily transit costs ranged from 27-54% of basal metabolic rate, 7-19% of daily energy expenditure, and 8-20% of daily dietary intake of rice (Oryza sativa). Our findings that flight distance and duration increased with date within wintering period were consistent with predictions of refuging theory, but alternative hypotheses also could explain these results. Evening flights of Northern Pintails roosting on Lacassine NWR were greater in distance and duration than those reported for most other species of wintering waterfowl. We recommend that proximity of refuges to feeding sites be considered in conservation and management plans for wintering Northern Pintails and other refuging waterfowl.

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.

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