For overwintering species, individuals' ability to find refugia from inclement weather and predators probably confers strong fitness benefits. How animals use their environment can be mediated by their personality (e.g. risk-taking), but does personality mediate how overwintering species select refugia? Snow cover is a dynamic winter characteristic that can influence crypsis or provide below-the-snow refugia. We explored how wintering ruffed grouse ( Bonasa umbellus ) selected snow roosting sites, a behaviour that reduces stress and cold exposure. We linked selection for approximately 700 roosts with survival of 42 grouse, and showed that grouse generally selected deeper snow and warmer areas. Grouse found in shallow snow were less likely to survive winter. However, individuals that selected deep snow improved their survival, suggesting that demographic consequences of selecting winter refugia are mediated by differences in personality . Our study provides a crucial, and seldom addressed, link between personality in resource selection and resulting demographic consequences.

Decision support systems are now mostly computer and internet-based information systems designed to support land managers with complex decision-making. However, there is concern that many environmental and agricultural decision support systems remain underutilized and ineffective. Recent efforts to improve decision support systems use have focused on enhancing stakeholder participation in their development, but a mismatch between stakeholders' expectations and the reality of decision support systems outputs continues to limit uptake. Additional challenges remain in problem-framing and evaluation. We propose using an outcomes-based approach called theory of change in conjunction with decision support systems development to support both wider problem-framing and outcomes-based monitoring and evaluation. The theory of change helps framing by placing the decision support systems within a wider context. It highlights how decision support systems use can "contribute" to long-term outcomes, and helps align decision support systems outputs with these larger goals. We illustrate the benefits of linking decision support systems development and application with a theory of change approach using an example of pest rabbit management in Australia. We develop a theory of change that outlines the activities required to achieve the outcomes desired from an effective rabbit management program, and two decision support systems that contribute to specific aspects of decision making in this wider problem context. Using a theory of change in this way should increase acceptance of the role of decision support systems by end-users, clarify their limitations and, importantly, increase effectiveness of rabbit management. The use of a theory of change should benefit those seeking to improve decision support systems design, use and, evaluation.

Currently there are few robust techniques being used in New Zealand to assess the results of pest control targeting predatory mammals such as stoats (Mustela erminea), feral cats (Felis catus) and hedgehogs (Erinaceus europaeus), with most operations using capture rates from kill traps as a measure of success. We conducted field trials of camera traps to detect these species at two sites-Macraes Flat and Tasman Valley-where intensive predator trapping is conducted by the New Zealand Department of Conservation. We compared camera traps with kill traps in terms of capture rate per 100 trap nights. Camera traps detected all three target species, as well as various non-target animals. Capture rates of cats and hedgehogs were higher with cameras than with kill traps. Comparisons for stoats were inconclusive due to a low number of detections. We suggest that camera traps are suitable for monitoring relative abundance of cats and hedgehogs, and recommend further testing in areas of higher stoat abundance.

Urbanization causes the simplification of natural habitats, resulting in animal communities dominated by exotic species with few top predators. In recent years, however, many predators such as hawks, and in the US coyotes and cougars, have become increasingly common in urban environments. Hawks in the Accipiter genus, especially, are recovering from widespread population declines and are increasingly common in urbanizing landscapes. Our goal was to identify factors that determine the occupancy, colonization and persistence of Accipiter hawks in a major metropolitan area. Through a novel combination of citizen science and advanced remote sensing, we quantified how urban features facilitate the dynamics and long-term establishment of Accipiter hawks. Based on data from Project FeederWatch, we quantified 21 years (1996–2016) of changes in the spatio-temporal dynamics of Accipiter hawks in Chicago, IL, USA. Using a multi-season occupancy model, we estimated Cooper's ( Accipiter cooperii ) and sharp-shinned ( A. striatus ) hawk occupancy dynamics as a function of tree canopy cover, impervious surface cover and prey availability. In the late 1990s, hawks occupied 26% of sites around Chicago, but after two decades, their occupancy fluctuated close to 67% of sites and they colonized increasingly urbanized areas. Once established, hawks persisted in areas with high levels of impervious surfaces as long as those areas supported high abundances of prey birds. Urban areas represent increasingly habitable environments for recovering predators, and understanding the precise urban features that drive colonization and persistence is important for wildlife conservation in an urbanizing world.

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Threatened species are managed using diverse conservation tactics implemented at multiple scales ranging from protecting individuals, to populations, to entire species. Individual protection strives to promote recovery at the population‐ or species‐level, although this is seldom evaluated. After decades of widespread declines, bald eagles, Haliaeetus leucocephalus, are recovering throughout their range due to legal protection and pesticide bans. However, like other raptors, their recovery remains threatened by human activities. Bald eagle nests are commonly managed using buffer zones to minimize human disturbance, but the benefits of this practice remain unquantified. Within Voyageurs National Park (VNP), Minnesota, USA, managers have monitored bald eagle populations for over 40 years, and since 1991, have protected at‐risk nests from human disturbance using buffer zones (200 and 400 m radius). We aimed to (1) quantify the recovery of bald eagles in VNP (1973–2016), and (2) provide a first‐ever evaluation of the individual‐ and population‐level effects of managing individual nests. To do so, we developed Bayesian Integrated Population Models combining observations of nest occupancy and reproductive output (metrics commonly collected for raptors) to estimate nest‐level probabilities of occupancy, nest success, and high productivity (producing ≥2 nestlings), as well as population‐level estimates of abundance and growth. The breeding population of bald eagles at VNP increased steadily from <10 pairs in the late 1970s to 48 pairs by 2016. At the nest‐level, management significantly improved occupancy and success. At the population‐level, management led to 8% and 13% increases in nest success and productivity rates, respectively, resulting in a 37% increase in breeding pair abundance. Synthesis and applications. There is a clear need to evaluate how management approaches at multiple scales assist in species recovery. Our study uses an Integrated Population Model to reveal the population‐level benefits of a widely used, individual‐based management action (protecting nests using buffer zones) on a recovering raptor.

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Predator-prey systems can extend over large geographical areas but empirical modelling of predator-prey dynamics has been largely limited to localised scales. This is due partly to difficulties in estimating predator and prey abundances over large areas. Collection of data at suitably large scales has been a major problem in previous studies of European rabbits (Oryctolagus cuniculus) and their predators. This applies in Western Europe, where conserving rabbits and predators such as Iberian lynx (Lynx pardinus) is important, and in other parts of the world where rabbits are an invasive species supporting populations of introduced, and sometimes native, predators. In pastoral regions of New Zealand, rabbits are the primary prey of feral cats (Felis catus) that threaten native fauna. We estimate the seasonal numerical response of cats to fluctuations in rabbit numbers in grassland–shrubland habitat across the Otago and Mackenzie regions of the South Island of New Zealand. We use spotlight counts over 1645 km of transects to estimate rabbit and cat abundances with a novel modelling approach that accounts simultaneously for environmental stochasticity, density dependence and varying detection probability. Our model suggests that cat abundance is related consistently to rabbit abundance in spring and summer, possibly through increased rabbit numbers improving the fecundity and juvenile survival of cats. Maintaining rabbits at low abundance should therefore suppress cat numbers, relieving predation pressure on native prey. Our approach provided estimates of the abundance of cats and rabbits over a large geographical area. This was made possible by repeated sampling within each season, which allows estimation of detection probabilities. A similar approach could be applied to predator-prey systems elsewhere, and could be adapted to any method of direct observation in which there is no double-counting of individuals. Reliable estimates of numerical responses are essential for managing both invasive and threatened predators and prey.