Current waterfowl populations provide liberal hunting seasons, but waterfowl hunter numbers have declined since the mid-1990s. We hypothesized that trends in waterfowl hunter numbers, as indicated by Federal Migratory Bird Hunting Conservation Stamp (duck stamp) sales, have become independent of breeding duck populations, and we assess the impacts on habitat conservation. The relationship between duck breeding populations and duck stamp sales changed between 1955-1994 (r ¼ 0.81) and 1995-2008 (r ¼ 0.29). Based on the 1955-1994 relationship between total duck breeding population and duck stamp sales, about 600,000 fewer duck stamps than expected were sold annually during 1995-2008. This equates to a loss of US$126 million in gross revenue and from 42,500 to 80,900 fewer hectares of wetland and upland hectares protected. The current relationship between duck breeding population and duck stamp sales suggests future estimates of waterfowl hunters will decrease below 1 million when the breeding population declines below 32 million. Assuming current trends, expected losses of duck stamp revenues may result in an additional 2,800-13,900 unprotected ha/year if the duck breeding population declines to historical lows. Development and implementation of programs and policies that maintain or increase participation in waterfowl hunting will assist in habitat conservation efforts and continue waterfowl hunting traditions. ß 2013 The Wildlife Society.

Animal site fidelity structures space use, population demography and ultimately gene flow. Understanding the adaptive selection for site fidelity patterns provides a mechanistic understanding to both spatial and population processes. This can be achieved by linking space use with environmental variability (spatial and temporal) and demographic parameters. However, rarely is the environmental context that drives the selection for site fidelity behaviour fully considered. We use ecological theory to understand whether the spatial and temporal variability in breeding site quality can explain the site fidelity behaviour and demographic patterns of Gunnison sage‐grouse (Centrocercus minimus). We examined female site fidelity patterns across multiple spatial scales: proximity of consecutive year nest locations, space‐use overlap within and across the breeding and brooding seasons, and fidelity to a breeding patch. We also examined the spatial and temporal variability in nest, chick, juvenile and adult survival. We found Gunnison sage‐grouse to be site faithful to their breeding patch, area of use within the patch and generally where they nest, suggesting an “Always Stay” site fidelity strategy. This is an optimal evolutionary strategy when site quality is unpredictable. Further, we found limited spatial variability in survival within age groups, suggesting little demographic benefit to moving among patches. We suggest Gunnison sage‐grouse site fidelity is driven by the unpredictability of predation in a relatively homogeneous environment, the lack of benefits and likely costs to moving across landscape patches and leaving known lek and breeding/brooding areas. Space use and demography are commonly studied separately. More so, site fidelity patterns are rarely framed in the context of ecological theory, beyond questions related to the win‐stay:lose‐switch rule. To move beyond describing patterns and understand the adaptive selection driving species movements and their demographic consequences require integrating movement, demography and environmental variability in a synthetic framework. Site fidelity theory provides a coherent framework to simultaneously investigate the spatial and population ecology of animal populations. Using it to frame ecological questions will lead to a more mechanistic understanding of animal movement, spatial population structuring and meta‐population dynamics. A free Plain Language Summary can be found within the Supporting Information of this article.

Preserving avian flyway connectivity has long been challenged by our capacity to meaningfully quantify continental habitat dynamics and bird movements at temporal and spatial scales underlying long-distance migrations. Waterbirds migrating hundreds or thousands of kilometers depend on networks of wetland stopover sites to rest and refuel. Entire populations may rely on discrete wetland habitats, particularly in arid landscapes where the loss of limited stopover options can have disproportionately high impacts on migratory cost. Here, we examine flyway connectivity in water-limited ecosystems of western North America using 108 GPS tagged greater sandhill cranes. Bird movements were used to reconstruct wetland stopover networks across three geographically unique sub-populations spanning 12 U.S.-Mexican states and Canadian provinces. Networks were monitored with remote sensing to identify long-term trends in wetland and agricultural resources supporting migration and evaluated using network theory and centrality metrics as a measure of stopover site importance to flyway connectivity. Sandhill crane space use was analyzed in stopover locations to identify important ownership and landscape factors structuring bird distributions. Migratory efficiency was the primary mechanism underpinning network function. A small number of key stopover sites important to minimizing movement cost between summering and wintering locations were essential to preserving flyway connectivity. Localized efficiencies were apparent in stopover landscapes given prioritization of space use by birds where the proximity of agricultural food resources and flooded wetlands minimized daily movements. Model depictions showing wetland declines from 16% to 18% likely reflect a new normal in landscape drying that could decouple agriculture-waterbird relationships as water scarcity intensifies. Sustaining network resilience will require conservation strategies to balance water allocations preserving agricultural and wetlands on private lands that accounted for 67-96% of habitat use. Study outcomes provide new perspectives of agroecological relationships supporting continental waterbird migration needed to prioritize conservation of landscapes vital to maintaining flyway connectivity.

21Characterizing animal space use is critical to understand ecological relationships. Despite 22 many decades of using radio-telemetry to track animals and make spatial inference, there are 23 few statistical options to handle these unique data and no synthetic framework for modeling 24 animal location uncertainty and accounting for it in ecological models. We describe a novel 25 azimuthal telemetry model (ATM) to account for azimuthal uncertainty with covariates and 26 propagate location uncertainty into ecological models. We evaluate the ATM with commonly 27 used estimators in several study design scenarios using simulation. We also provide illustra- 28 tive empirical examples, demonstrating the impact of ignoring location uncertainty within 29 home range and resource selection analyses. We found the ATM to have good performance 30 and the only model that has appropriate measures of coverage. Ignoring animal location un-31 certainty when estimating resource selection or home ranges can have pernicious effects on 32 ecological inference. We demonstrate that home range estimates can be overly confident and 33 conservative when ignoring location uncertainty and resource selection coefficients can lead 34 to incorrect inference and over confidence in the magnitude of selection. Our findings and 35 model development have important implications for interpreting historical analyses using 36 this type of data and the future design of radio-telemetry studies. 37 Introduction 38 Understanding animal space-use and its implications for population and community dynam-39 ics is a central component of ecology and conservation biology. The need to understand 40 animal spatial relationships has led to the increasing refinement and utility of telemetry de-41 vices (Millspaugh et al. 2001). Traditional telemetry data were solely collected using VHF 42 ("very high frequency") radio signals to track individual animals with radio tags; VHF radio-43 telemetry started around the mid-1960s and is still often employed. These data are collected 44 by observers recording azimuths in the direction of the radio signal from known locations. 45Modern telemetry data are often collected using Argos satellites, aerial location finding (i.e., 46 2 via fixed-winged aircraft), or the global positioning system (GPS). While newer forms of 47 telemetry data are often collected, radio-telemetry devices are still relatively inexpensive. 48They also typically have low energy requirements, which allows for miniaturized and long-49 lasting devices to be fixed to small and volant animals for obtaining high spatial resolution 50 data with minimal risk to incurring costs on survival and movement (Ponchon et al. 2013). 51More so, digital VHF is quickly becoming an important way to monitor the movements of 52 small-bodied species at regional scales (Loring et al. 2017). 53It is well recognized that spatial locations from telemetry devices are not without 54 error and estimation uncertainty (Frair et al. 2004; Patterson et al. 2008). Observed locations ...

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