Animals select resources to maximize fitness but associated costs and benefits are spatially and temporally variable. Differences in wetland management influence resource availability for ducks and mortality risk from duck hunting. The local distribution of the Mallard ( Anas platyrhynchos ) is affected by this resource heterogeneity and variable risk from hunting. Regional conservation strategies primarily focus on how waterfowl distributions are affected by food resources during the nonbreeding season. To test if Mallard resource selection was related to the abundance of resources, risks, or a combination, we studied resource selection of adult female Mallards during autumn and winter. We developed a digital spatial layer for Lake St. Clair, Ontario, Canada, that classified resources important to Mallards and assigned these resources a risk level based on ownership type and presumed disturbance from hunting. We monitored 59 individuals with GPS back‐pack transmitters prior to, during, and after the hunting season and used discrete choice modeling to generate diurnal and nocturnal resource selection estimates. The model that classified available resources and presumed risk best explained Mallard resource selection strategies. Resource selection varied within and among seasons. Ducks selected for federal, state and private managed wetland complexes that provided an intermediate or relatively greater amount of refuge and foraging options than public hunting areas. Across all diel periods and seasons, there was selection for federally managed marshes and private supplemental feeding refuges that prohibited hunting. Mallard resource selection demonstrated trade‐offs related to the management of mortality risk, anthropogenic disturbances, and foraging opportunities. Understanding how waterfowl respond to heterogeneous landscapes of resources and risks can inform regional conservation strategies related to waterfowl distribution during the nonbreeding season.

Determining origins of waterfowl is important for establishing appropriate management and conservation strategies. In North America, much information is available from long-term mark-recapture programs involving banding on breeding or molting grounds. However, this approach is less able to identify origins of individuals across broad areas where banding effort is low. We used stable-hydrogen isotope analyses of feathers (δ 2 H f) from Mallards (Anas platyrhynchos) harvested during the 2014-2015 and 2015-2016 hunting seasons at Lake St. Clair (LSC), Ontario, Canada (n = 237 individuals). We created a feather isoscape and applied Bayesian assignment approaches to determine probability of origin. The proportion of hatch-year Mallards produced locally, i.e., at the same latitude as LSC, as opposed to farther north or south of LSC, ranged from 13.1% to 22.0% with almost no difference by sex. The proportion of after-hatch-year (AHY) birds that molted locally ranged from 3.5% to 11.7%, with slightly fewer local AHY females compared with local AHY males. Nearly all birds that did not originate locally came from latitudes to the north of LSC, and only 2 from south of LSC. Whether this pattern is representative of locations in the Great Lakes beyond our study area is unknown but is of great relevance for harvest management. As such, we are expanding our study with plans to examine isotope-based origins of Mallards and other harvested waterfowl species at locations throughout the Great Lakes region. Because of its unique potential to fill knowledge gaps, we advocate the use of the stable isotope technique in the management of North American waterfowl and encourage more research in this area. Origines des colverts prélevés sur le Lac St. Clair, dans l'Ontario : approche par isotopes stables RÉSUMÉ. La détermination des origines des oiseaux aquatiques est importante pour établir des stratégies appropriées de gestion et de conservation. En Amérique du Nord, de nombreuses informations sont disponibles auprès des programmes de marquage-recapture à long terme qui comprennent le marquage des territoires de reproduction ou de mue. Toutefois, cette approche est moins efficace pour identifier les origines des individus dans de vastes régions où l'effort de marquage est peu important. Nous avons utilisé les analyses par isotopes d'hydrogène stable sur les plumes (δ2Hf) de colverts (Anas platyrhynchos) prélevés au cours des saisons de chasse 2014-2015 et 2015-2016 sur le lac St. Clair (LSC), dans l'Ontario, au Canada (n = 237 individus). Nous avons créé une isocarte des plumes et appliqué des modèles d'affectation bayesiens pour déterminer la probabilité d'origine. La proportion de colverts de l'année produits localement, c'est-à-dire à la même latitude que le LSC, par opposition aux individus provenant de régions plus au nord ou au sud du LSC, variait de 13,1 % à 22,0 %, pratiquement sans différence entre les sexes. La proportion d'oiseaux après l'année d'éclosion qui avaient mué localement variait de 3,5 % à 11,7 %, les femelles étan...

Autumn waterfowl habitat management often focuses on providing high energy food resources to attract and concentrate waterfowl for harvest. Similarly, many waterfowl conservation plans assume food resources are the primary, controllable limiting factor influencing waterfowl distribution during migration; however, hunting‐related disturbance also influences waterfowl distribution in autumn. We investigated factors influencing mallard (Anas platyrhynchos) movements in an intensively hunted and food‐rich landscape in Ohio, USA, during autumn of 2015 and 2016. We used locations from female mallards equipped with global positioning system (GPS) back‐pack‐transmitters to determine the probability of mallards switching land cover types based on seasonal and daily patterns of hunting disturbance and to determine the distances mallards moved between cover types that offer refuge and those that offer food resources as evidence for or against food resource depletion during the hunting season. Mallards switched cover types to exploit food‐rich but intensively hunted locations nocturnally and cover type switching during times subject to disturbance increased significantly from the early segment to the late segment of hunting season. Distances mallards moved between refuge cover types and food‐rich cover types did not change over the duration of the study. Hunting disturbance is a key variable influencing autumn movements and distribution of mallards, and mallards in a food‐rich and intensively hunted landscape likely employ nocturnal foraging as a strategy to survive autumn migration. Nocturnal foraging behavior has consequences for waterfowl managers tasked with providing quality waterfowl hunting opportunities because ducks that forage only at night are largely unavailable to hunters. © 2020 The Wildlife Society.

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Determining the source areas of harvested individuals is important for effective conservation and management of migratory game birds. Banding has provided much information about source areas, but obtaining samples of marked individuals representative of all potential breeding areas is difficult for most species. To add to previous knowledge of harvest derivation based on banding data and to assist with regulatory decisions, we used stable hydrogen isotope (d 2 H) techniques to estimate natal and molt source areas of Blue-winged Teal (Spatula discors) harvested in southern Canada in 2014 and 2017. We found that most birds harvested in southern Saskatchewan, southern Manitoba, northern Ontario, and southern Ontario likely originated in the prairie and boreal plains regions of Canada and the United States, which is the core production area for the species. Based on feather d 2 H values, some birds harvested in Ontario may have also originated in Ontario. Our results differ from those of a long-term analysis of band recovery data that revealed that most Blue-winged Teal harvested in Ontario originated in the eastern part of the province and areas along the lower Great Lakes and southwestern Quebec. We found that nearly all birds harvested in Ontario in our study likely originated from areas north and west of the province. Together, banding and stable isotopes likely provide the best information available on source areas of harvested birds for regulatory decision making. RESUMEN.Areas de origen de Spatula discors cazadas en Ontario y Prairie Canad a con base en is otopos estables: implicaciones para el manejo sostenible Es importante determinar las areas de origen de animales de caza para la conservaci on efectiva y el manejo de aves de caza migratorias. El anillamiento ha provisto mucha informaci on sobre estas areas, pero obtener muestras de individuos marcados que sean representativas de todas las areas de reproducci on potenciales es dif ıcil para la mayor ıa de las especies. Con el fin de contribuir con informaci on previa del origen de las aves cazadas con base en datos de anillos y para asistir en la toma de decisiones regulatorias, utilizamos t ecnicas de isotopos estable de hidr ogeno (d 2 H) para estimar areas de nacimiento y muda de Spatula discors cazadas en el sur de Canad a entre 2014 y 2017. Encontramos que la mayor ıa de las aves fueron cazadas en el sur de Saskatchewan, el sur de Manitoba, el norte de Ontario y el sur de Ontario probablemente se originaron en la regi on de praderas y planicies boreales de Canad a y Estados Unidos, el cual es el area nuclear de reproducci on de esta especie. Con base en los valores de d 2 H de las plumas, algunas aves que fueron cazadas en Ontario pueden, tambi en, haberse originado en Ontario. Nuestros resultados difieren de los resultados de los an alisis de largo plazo utilizando datos de anillos recuperados que suger ıan que la mayor ıa de Spatula discors cazados en Ontario se originaban en la regi on este de la provincia y las areas a lo largo de la regi on baja d...

Context The North American Waterfowl Management Plan and the Upper Mississippi River/Great Lakes Joint Venture waterfowl habitat conservation strategy provide continental and regional guidance, respectively, for waterfowl habitat conservation planning. They were not designed to guide watershed- scale waterfowl habitat delivery. Objective Our goal was to develop a waterfowl habitat decision support framework for the state of Wisconsin using biological and social criteria to guide state and local-scale practitioners with an explicit link to larger scale objectives. Methods We engaged a core group of wetland and waterfowl experts to decide upon decision support layers relevant to biological and social objectives, evaluate variables, establish weights, and review model outputs for reasonableness and accuracy. We used spatial analyst tools, kernel density estimators, and weighted sums to create spatially explicit models to identify landscapes and watersheds important for waterfowl. We identified habitat resources that exist currently (Conservation Capital) and considered potential resources (Conservation Opportunities) which could enhance wetland restoration efforts. Results We developed a transparent framework to identify and prioritize landscapes for conserving waterfowl habitat at the Hydrologic Unit Code 12 watershed scale in Wisconsin, by maintaining continental and regional priorities, and including local landscape characteristics, biological criteria, and researcher, manager, and biologist expertise. Conclusions Local detail is critical for implementing waterfowl habitat delivery and making efficient use of limited funds for conservation but can be more abstract in larger regional or continental conservation planning. Our models are science-based, transparent, defensible, and can be modified as social, political, biological, and environmental forces change.

Relationships between individual resource selection strategies and fitness are difficult to quantify at large spatial scales. These links are important for understanding the potential effects of management on population‐level processes. We modeled the degree to which selection of specific landscape features altered mortality risk of female mallards (Anas platyrhynchos) during the non‐breeding season. We used individual resource selection estimates from adult female mallards equipped with Global Positioning System (GPS) backpack transmitters (n = 56) in the Lake St. Clair region of southwestern Ontario, Canada, in August of 2014 and 2015. We determined the fate of individuals between August and January and used time‐to‐event analyses to model survival over 158 days. Furthermore, we investigated how diurnal and nocturnal resource selection and year were related to mortality risk. The survival rate for the adult female mallards was 0.57 (95% CI = 0.42–0.77). Resource types were combinations of land class types (e.g., water, marsh, flooded agriculture, supplemental feeding areas, and dry agriculture) important to mallards and varying levels of risk from anthropogenic disturbance ranging from inviolate refuges to publicly accessed areas where we predicted mortality risk to be greatest. Our results suggest that water that the public can access (i.e., public water) influenced mortality risk during multiple seasons. Specifically, selection of public water by female mallards reduced mortality risk diurnally during the non‐hunting period (hazard ratio = 0.68, 95% CI = 0.48–0.96) but increased mortality risk during the first half of the hunting period (hazard ratio = 1.54, 95% CI = 1.08–2.20). Our research highlights that individual selection strategies by ducks within this landscape can influence mortality risk.

The Mississippi Department of Wildlife, Fisheries, and Parks utilize data from turkey hunter observations and brood surveys from across the state to manage wild turkey Meleagris gallopavo populations. Since 1995, hunters have collected gobbling and jake observation data, while the Mississippi Department of Wildlife, Fisheries, and Parks' personnel and cooperating wildlife managers of several natural resource agencies throughout the state have collected brood survey data. Both sources of data serve to forecast poult recruitment and gobbling activity. The objective of this study was to evaluate if these data can serve as a viable predictor of gobbling activity. We used three mixed models to investigate the relationship between the number of jakes observed per hour of hunting 1 y prior and the total number of poults per hens 2 y prior (model 1), number of gobblers heard per hour of hunting and the number of jakes observed per hour of hunting 1 y prior (model 2), the number of gobblers heard per hour of hunting and the total number poults per total hens observed 2 y prior (model 3) using data from 1995 to 2008 among five wild turkey management regions encompassing the state. We incorporated region as a random effect to account for spatial variation. We found the number of jakes observed per hour of hunting 1 y prior correlated with the total number of poults per total hens observed 2 y prior. We also found the number of gobblers heard per hour of hunting correlated with the number of jakes observed per hour of hunting 1 y prior. Additionally, we found that the total poults per total hens observed 2 y prior was correlated to the number of gobblers heard per hour of hunting. Our results show promise for using indices of gobbling activity, jake observations, and brood surveys to estimate gobbling activity.