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Understanding of a migratory bird species' movements and winter fidelity provides insights to various population and genetic parameters that may support conservation efforts. Trumpeter Swans (Cygnus buccinator) were reintroduced into the Nebraska Sandhills beginning in the 1960s but knowledge of the ecology of these birds is limited. We examined the winter movements, home range, and fidelity of swans in the Nebraska Sandhills, 2014–2020. We captured and fitted solar-powered GPS transmitters via neck collars to swans during the summer molting period. We used movement patterns and weather data to define timing of transitions from breeding and post-breeding areas to wintering areas. The research findings showed that only one swan made a long-distance movement out of Nebraska during the winter. Mean distance (±SD) moved from breeding or post-breeding areas to their initial wintering complex was 53.4 (±52.7) km. Swans spent most (77.2%) of their time on one wintering complex and 75% of their time at one wintering site. Swans used an average of 2.7 different wintering complexes and moved among complexes 6.4 (±3.6) times. Swans in our sample used an average of 1.5 wintering sites within complexes and moved 3.1 (±3.6) times among wintering sites. Swan fidelity (proportion returning) to wintering complexes was 0.72 and to wintering sites was 0.69. Return rate to their primary wintering complex and site was 100%. Fidelity rates to wintering complexes of swans with cygnets at time of capture and those without were 0.79 and 0.55, respectively. Swan movements in the Nebraska Sandhills indicate that they are willing to move among areas but tend to show fidelity to wintering areas. Changes in wintering habitat may alter patterns of fidelity, but swans may be able to adapt and move to alternative areas. Rivers, creeks, and other areas are important to wintering swans breeding in the Nebraska Sandhills and contribute to the sustainable conservation of swans. [ABSTRACT FROM AUTHOR]

Tier II bag limit regulations were developed to lessen constraints to participation by new duck hunters. By opting for the three-duck bag limit, hunters would not be subject to the species and sex-specific regulations of the six-duck limit. We surveyed hunters in Nebraska and South Dakota to gain an understanding about how Tier II regulations would be received by the current waterfowl-hunting population. We found that less experienced hunters stated they had greater difficulty identifying ducks and were more likely to use Tier II than experienced hunters. A significant proportion of new waterfowl hunters may make use of Tier II, and these regulations may relieve hunting constraints in a meaningful way. Wildlife agencies may want to consider how hunters transition between bag-limit regulations from year-to-year and consider means to integrate Tier II into hunter R3 efforts. [ABSTRACT FROM AUTHOR]

The number of waterfowl hunters in the United States has declined since the 1980s despite relatively abundant waterfowl populations and liberal hunting regulations. Programs focused on recruiting, retaining, and reactivating (R3) waterfowl hunters have become important to avoid further losses in traditional revenue for habitat management and protection and political support for waterfowl conservation and management. We focus on 4 waterfowl hunter population vital rates (i.e., recruitment rate, retention probability, license purchase probability, realized population growth rate), which can be used to improve the effectiveness of waterfowl hunter R3 activities and initiatives by providing a deeper understanding of waterfowl hunter population dynamics to determine who programs should target, where programs should be targeted, and finally the evaluation of programs. To do so, we analyzed Nebraska state electronic license data from 2012-2019 using Pradel survival and recruitment models in a mark-recapture framework. Female waterfowl hunter recruitment was higher than males; however, retention and license purchase probabilities were lower. Recruitment was highest in younger generations and retention highest in older generations. License purchase probabilities were highest among those in the oldest and youngest generations. The availability of hunting opportunity increased license purchase probabilities but had a minimal influence on retention and no association with recruitment. There were weak relationships between rurality and recruitment, and retention and license purchase probabilities. Finally, belonging to Ducks Unlimited was positively associated with higher license purchase and retention probabilities. Targeting an increase in license purchase probability by promoting social support for hunters through conservation organization membership should be a focus of waterfowl hunter R3 efforts to have the greatest influence on increasing waterfowl hunter participation. [ABSTRACT FROM AUTHOR]

Sand and gravel mining creates novel ecosystems along the Platte, Loup, and Elkhorn rivers in Nebraska, USA. Piping plovers and least terns are state and/or federally threatened and endangered species, respectively, that nest and raise young at these sites and their derivatives. Despite hosting relatively large numbers of piping plovers and least terns for decades, an important question that has largely gone unaddressed is whether the industry that has produced these novel ecosystems is stable and will continue to produce habitat consistently in the future. We evaluated how the number, size, and spatial distribution of different site types hosting different numbers of nesting plovers and terns have changed over time and how current trends in the number of different site types will affect future habitat using a multi‐state modeling approach. Overall area and total number of sites declined during the period 1993–2020. More important, one site type, traditional mines, are being replaced by another site type, modern mines, which host lower numbers of nests of both species. The difference between these two site types is primarily how waste sand is stored. Traditional mines store waste sand in spoil piles or plumes along the edge of a lake created by the mining process, forming relatively large expanses of nesting habitat used by both species. Modern mines store waste sand in limited quantities along the edge of the lake but also in piles away from the lake. Traditional mines also differ from modern mines in that they are routinely converted to housing developments with intermediate transition sites that host the largest number of nests for brief periods. Based on the previous 28 yr of decline, traditional mines and their productive derivatives are projected to continue to decline, thereby further reducing overall nesting habitat. Piping plovers and least terns are expected to nest in our study sites for the foreseeable future, but overall numbers are expected to be smaller than what has been observed in previous decades. Local declines in our study area will have local and regional implications for the recovery and management of these two species of conservation concern. [ABSTRACT FROM AUTHOR]

Harvest regulations are used to manage game species. Across their range, Canada geese Branta canadensis have recovered from near extirpation and are now perceived as overabundant and even a nuisance or a threat to human safety in many regions. Like many states, Nebraska has liberalized harvest regulations to increase recreation opportunities for consumptive users and to control increasing numbers of Canada geese. However, the efficacy of harvest regulations to control goose abundance is unclear. We used a live capture–recapture and dead recovery data set of more than 19,000 Canada geese banded in Nebraska 2006–2017 to determine the effect of liberalized harvest regulations on goose survival and overall growth rate. Our goals were to 1) estimate demographic parameters for Canada geese in five different regions in Nebraska; 2) estimate the effect of increasing daily bag limits during the early September season and regular season on survival of hatch-year, juvenile, and adult Canada geese; and 3) relate the effect of estimated changes in survival to regional growth rates. We found that survival (0.54–0.87), fidelity (0.14–0.99), and productivity (number of young per adult, 0.17–2.08) varied substantially among regions within Nebraska. We found that increasing early-season bag limits, but not regular-season bag limits, reduced survival in Canada geese. However, this effect was greatest when comparing years without an early season to years with the highest daily bag limits used in Nebraska (eight). Survival of juvenile geese (2–3 y posthatch) were unaffected by changes in daily bag limits during any season, though the probability of reporting was greatest for this age class. The observed reductions in survival probability of hatch-year and adult geese due to increased daily bag limits during the early season (< 10%) led to a decrease in regional growth rates of ∼5% between years with the most liberal early-season daily bag limits and years without an early season. Our results suggest that increased bag limits during the early season may reduce Canada goose survival, but not enough to affect regional growth rates in Nebraska. [ABSTRACT FROM AUTHOR]

Migration ecology and habitat use of spring migrating birds using the Central Platte River is a well-explored topic, yet less is known about use of the North and South Platte rivers (NSPR) in western Nebraska. The efficiency and effectiveness of conservation efforts in the NSPR could be greatly improved with access to information about where and when birds roost and landscape prioritization tools. We used aerial surveys to determine population distribution and migration phenology of sandhill cranes Antigone canadensis, Canada geese Branta canadensis, and ducks using the NSPR for roosting during the mid-February to mid-April spring migration. We used these data and geospatial information to identify important river reaches for these species and habitat covariates that discriminate between those used at lower and higher densities. We found that sandhill cranes and waterfowl generally roosted in different segments of the NSPR and, subsequently, different factors were associated with high densities. Sandhill crane density was positively correlated with distance from obstructions greater than 1 m high and negatively correlated with area of unvegetated sandbar within 1 km. Density of Canada geese and ducks was high in segments positively associated with wetland and sand pit habitats. Human disturbance variables such as roads and bridges in this rural region had little effect on identification of roosting areas used by high densities of all groups. On the basis of our results, habitat conservation efforts that specifically target sandhill cranes will not have similar positive effects on waterfowl use and distribution in the NSPR. Our identification of the most important river segments should allow managers to better target land acquisition or management resources to areas that will have the greatest effect on either waterfowl or sandhill cranes during spring migration. [ABSTRACT FROM AUTHOR]

Using an online survey completed by individuals who hunted deer, waterfowl, upland game, or spring turkey in Nebraska during the 2017–2018 hunting seasons, we applied importance-grid analysis (IGA) and penalty-reward-contrast analysis (PRCA) to examine how activity-related attributes are related to satisfaction for each type of hunting activity. Effective response rates for the deer, waterfowl, small and upland-game, and spring turkey hunting surveys were 23%, 16%, 19%, and 27%, respectively. Results suggested that among hunting activities, different attributes were related to their sense of satisfaction. PRCA identified "seeing game animals" as a minimum requirement for participation in all activities except waterfowl hunting. "Seeing game birds" and "harvesting the daily bag limit" were identified as attributes that related to satisfaction and dissatisfaction among waterfowl hunters. Our study provides insights into factors that are important to satisfaction for each hunting activity. [ABSTRACT FROM AUTHOR]

Waterfowl nutritional requirements and food availability at migration stopover habitats may differ from those at nesting or wintering areas. Although there is little information on factors that influence waterfowl diets and food selection during migration, we hypothesized that bird age and wetland density in the surrounding landscape would influence food selection. Thus, the objective of this study was to quantify mallard Anas platyrhynchos and blue-winged teal Anas discors diets during migration and evaluate effects of age and wetland density on waterfowl food selection. We collected 30 mallards and 29 blue-winged teal with food items present in esophagi from wetlands in south-central Nebraska during spring 2008 and 2009. Smartweed Polygonum spp. and barnyard grass Echinochloa spp. were the most common seeds found in both mallards and blue-winged teal, while Naididae and Chironomidae larvae were the most common invertebrates in mallard and blue-winged teal diets, respectively. Invertebrates were consumed by both species in greater proportion than available. Both mallards and blue-winged teal collected in wetland complexes selected some seeds over others, whereas birds in isolated wetlands foraged on foods in proportion to availability. After-hatch-year mallards also selected for some seeds over others, as compared with hatch-year birds, which foraged opportunistically on available foods. If after-hatch-year birds and birds in wetland complexes are able to be more selective in their diets relative to food availability at individual wetlands, they may be able to acquire and replenish lipids reserves more efficiently than hatch-year birds or birds in areas with lower wetland densities. [ABSTRACT FROM AUTHOR]

The article focuses on the factors that influence wetland birds behavior during spring migration. The study evaluated the behavior of wetland birds in the Rainwater Basin region of Nebraska during the spring season of 2002-2004. The effects of time period, hunting pressure and year on wetland behavior were evaluated. Among the birds that were studied include geese, dabbling ducks and shorebirds.

The article investigates the use of double-observer methodology to estimate breeding duck population in the Nebraska Sandhills. The method used aerial transect survey with two front seat observers and one rear seat observer. Estimate was done by social grouping by species while regional population sizes were estimated by extrapolating transects estimates to the Sandhills. The results suggest that double-observer methodology should be considered for adjusting duck counts that cannot be corrected using additional aerial or ground surveys.

Staging areas and migratory stopovers of wetland birds can function as geographic bottlenecks; common dependence among migratory wetland bird species on these sites has major implications for wetland conservation. Although 90% of playa wetlands in the Rainwater Basin (RWB) region of Nebraska, USA, have been destroyed, the area still provides essential stopover habitat for up to 10 million waterfowl each spring. Our objectives were to determine local (within wetland and immediate watershed) and landscape-scale factors influencing wetland bird abundance and species richness during spring migration at RWB playas. We surveyed 36-40 playas twice weekly in the RWB and observed approximately 1.6 million individual migratory wetland birds representing 72 species during spring migrations 2002-2004. We tested a priori hypotheses about whether local and landscape variables influenced overall species richness and abundance of geese, dabbling ducks, diving ducks, and shorebirds. Wetland area had a positive influence on goose abundance in all years, whereas percent emergent vegetation and hunting pressure had negative influences. Models predicting dabbling duck abundance differed among years; however, individual wetland area and area of semipermanent wetlands within 10 km of the study wetland consistently had a positive influence on dabbling duck abundance. Percent emergent vegetation also was a positive predictor of dabbling duck abundance in all years, indicating that wetlands with intermediate (50%) vegetation coverage have the greatest dabbling duck abundance. Shorebird abundance was positively influenced by wetland area and number of wetlands within 10 km and negatively influenced by water depth. Wetland area, water depth, and area of wetlands within 10 km were all equally important in models predicting overall species richness. Total species richness was positively influenced by wetland area and negatively influenced by water depth and area of semipermanent wetlands within 10 km. Avian species richness also was greatest in wetlands with intermediate vegetation coverage. Restoring playa hydrology should promote intermediate percent cover of emergent vegetation, which will increase use by dabbling ducks and shorebirds, and decrease snow goose (Chen caerulescens) use of these wetlands. We observed a reduction in dabbling duck abundance on wetlands open to spring snow goose hunting and recommend further investigation of the effects of this conservation order on nontarget species. Our results indicate that wildlife managers at migration stopover areas should conserve wetlands in complexes to meet the continuing and future habitat requirements of migratory birds, especially dabbling ducks, during spring migration. [ABSTRACT FROM AUTHOR]

The article discusses the findings of two surveys about waterfowl hunter crowding and its influence on dissatisfaction with outdoor experiences. Due to unlimited access for hunters at the Santee Area in the Lewis and Clark Lake on the Missouri River between Nebraska and South Dakota, crowding became a problem in the area. It describes the mail survey among duck hunters and the boat ramp survey on duck hunting experience and satisfaction. The mail survey revealed a crowding problem while the boat ramp survey found that crowding is also a resource problem.