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[Display omitted] • Species distribution models (SDMs) combine data on species occurrence and environment. • The SDM performance predicting species occurrence can be measured as the goodness-of-fit. • We compared the goodness-of-fit (GOF) of SDMs among 56 breeding bird species. • GOF was unrelated to species home-range, body mass, detectability or diet-specialization. • SDMs were more accurate for habitat-specialist species, mainly for grassland species. Species distribution models (SDMs) are numerical tools that combine species occurrence (or abundance) data with environmental variables, to predict the species' distribution spatially. SDMs are increasingly used for purposes of conservation planning and management of ecosystems. The model performance can be measured as the goodness-of-fit (GOF), which describes how well it fits (e.g., the discrepancy between the statistical model and the data observed). However, there is still a need for a deeper understanding of the ecological characteristics of the modelled species which can affect the accuracy of those models. Here, we compared the goodness-of-fit of SDMs, considering several ecological characteristics of 56 bird species: Most frequently used environment, body mass, home-range, species specialization index (SSI), diet specialization and detectability. All SDMs were performed on the same dataset, and the relative frequency of each species was also incorporated to account for occurrence heterogeneity. GOF of SDMs was not significantly correlated with species' frequency, home-range, body mass, degree of detectability or level of diet specialization. Overall, the birds with more accurate SDMs (GOF) were species of grasslands and the GOF was positively associated with SSI, indicating that more habitat-specialized species are better predictable. Our findings suggest that is important to focus not only on statistical issues potentially related to model performance but also on ecological characteristics of single species because can improve the performance of modellistic procedures, increasing their predictive power. [ABSTRACT FROM AUTHOR]

With increasing infrastructural development along Brazil's coast, environmental regulation measures are becoming increasingly necessary in the face of the damage caused by large projects that impact tropical forests. Brazilian legislation supports implementation of translocation programs for impacted fauna, especially threatened species such as the thin-spined porcupine Chaetomys subspinosus (Rodentia, Erethizontidae). Thus, we present a case study of a pioneer translocation program for the thin-spined porcupine in southeastern Brazil. We aimed to analyze the home-range and habitat selection of three translocated porcupines and one resident individual. In addition, we analyzed the success of the translocations. The porcupines were monitored by radiotelemetry for 3–16 months from October 2015 to March 2017 in a mosaic landscape of restinga forests (sandbank forest vegetation) within a eucalyptus matrix. The translocated porcupines had considerably larger home-ranges (14.29–18.36 ha, minimum convex polygon method – MCP) than did the resident animal (1.22 ha – MCP). We observed stabilization in the home-range size curves of the translocated females in the 7th − 9th month of monitoring. All translocated individuals achieved permanence within a preselected area, indicating adaptation to the new area. In addition, individuals showed a clear preference for restinga forests over drained eucalyptus plantations. Thus, our results demonstrate the feasibility of thin-spined porcupine translocations and the importance of maintaining restinga forest remnants outside of protected areas for the conservation and permanence of viable populations of this rodent. [ABSTRACT FROM AUTHOR]

Urbanization and agricultural intensification resulting in habitat loss is having a profound negative effect on grassland and farmland birds worldwide. Barn owls ( Tyto furcata ), as a species, have been affected by this intensification. To evaluate how urbanization and agricultural intensification affects barn owls we sought to address: 1) how human land use influences barn owl hunting behavior and diet, and 2) do habitat and prey choice influence the likelihood of barn owls consuming anticoagulant rodenticide (AR) exposed prey. We radio tagged 11 owls across the rural-urban landscape gradient in the Lower Mainland, British Columbia, and collected sufficient location data on 10 barn owls. We found that the 95% kernel home-ranges ranged from 1.0 to 28.5 km 2 ( n = 10) and were positively correlated with the proportion of urban land use within home-ranges. Barn owls across all landscapes selected roadside grass verges significantly more than other habitat types within home-ranges, which may reflect the loss of grassland associated agriculture in the region. The risk of consuming AR exposed prey was highest in roadside grass verges compared to other habitat types. However, the overall likelihood of consuming AR exposed prey significantly decreased when the proportion of grass patches within home-ranges increased, which suggests smaller linear grass sections are more likely to contain AR exposed small mammal prey. These results highlight the need to retain and enhance hunting habitat for barn owls during urban development and to mitigate the risk of barn owl road mortality along major highways. [ABSTRACT FROM AUTHOR]

The Timber Rattlesnake ( Crotalus horridus ) is a species of conservation concern throughout much of the Midwestern United States. While the habitat preferences of Timber Rattlesnakes have been studied throughout much of its range, little empirical data is available on the effects of forest management on this species. During 2007–11, we monitored movements of 47 adult Timber Rattlesnakes using radio telemetry in southcentral Indiana. Snakes were tracked during one or more seasons (April-October) for two years prior to, and three years following scheduled timber harvests (4-ha clearcuts and 4-ha understory removal as the first stage of shelterwood harvests). Annual home range estimates (100% Minimum Convex Polygon [MCP]) for both sexes combined ranged from 1.6 ha to 271.3 ha. The average home range for males (68.8 ha) was larger than for either non-gravid females (22.7 ha) or gravid females (11.7 ha). Mean home range size using MCPs or kernel density estimates did not change from pre- to post-harvest in control sites or even-aged sites for either sex. The daily distance traveled by snakes and their proportional use of areas within harvest boundaries did not differ between treatment periods. Canopy and understory removal on a small scale (approx. 4 ha) in a forested landscape did not affect seasonal or fine-scale movements of adult Timber Rattlesnakes 1–3 years post-harvest. Our results suggest that this scale of timber harvesting is compatible with Timber Rattlesnakes. [ABSTRACT FROM AUTHOR]

Urbanization impacts on the composition and distribution of wildlife. The tawny frogmouth ( Podargus strigoides ) is an endemic, nocturnal bird species widespread throughout Australia with recent research highlighting high densities within urban environments. The aim of this study was to investigate home-range size and land-use in response to a gradient of urbanization by determining (a) the key land-use types influencing home-range size and location in the urban landscape; (b) whether urbanization impacts on home-range size; and (c) whether the response to urbanization is gender specific. Twelve birds, seven male and five female were radio-tracked within a study zone located in Melbourne, Australia. We used minimum convex polygons (MCP) 95% and 50% fixed-kernel isopleths to calculate home-range size and areas of core use within each home-range. In both the landscape and core areas of their home-range, birds positioned their home-range in areas with more trees, avoiding impervious surfaces and utilizing grassed areas. Male mean kernel home-range was 17.65 ± 4.35 ha and female 6.55 ± 1.40 ha. Male home-ranges contained higher levels of impervious surfaces than females. Modelling demonstrated that as urbanization intensified the home-range size of males increased whereas female home-ranges remained static in size. This research identifies land-use selection and highlights the possibility that spatial behaviour in the species is sex-biased in response to a gradient of urbanization. [ABSTRACT FROM AUTHOR]

Abstract: Wide-ranging, landscape-level movements by terrestrial herbivores are increasingly threatened globally. Understanding the ecology of spatio-temporal movement patterns is critical for conservation of wide-ranging terrestrial species and the ecosystems on which they rely. The range of the Gourma elephant population inhabiting the Sahelian eco-region near Tombouctou (Timbuktu), Mali encompasses the largest areal extent in this species (29% greater than range sizes reported in other populations). Over the course of a year, the Gourma elephants (Loxodonta africana) move in a coordinated north–south movement pattern that is relatively unique for the species. We apply two new approaches to this system to characterize space use patterns; a time-density algorithm that provides a probability surface of normalized time spent per unit grid cell of GPS tracked animals and a velocity-grid algorithm that summarizes linear movements (directions, speeds and directional similarity) in cartographic form. The derived movement vector raster was analyzed using standard clustering methods to categorize areas by movement properties. Using these techniques we inferred regions of relative ecological importance to the Gourma elephants, protection of which is essential for the preservation of this unique terrestrial movement system. Analysis suggests the observed spatio-temporal pattern is a complex function of availability of surface water, vegetation productivity (as measured using the Normalized Difference Vegetation Index, NDVI) and possibly vegetation nutrient content. The approaches and applications demonstrated here can further our understanding of the movement ecology of other wildlife landscapes and facilitate the identification of crux points for their improved management. [Copyright &y& Elsevier]

Abstract: Statistical models that describe species-environmental relationships are important components within many wildlife conservation strategies. These models are typically developed from studies conducted on small geographic scales (hundreds of square kilometres), representing a relatively small range in environmental conditions. Such local models from local studies are often then extrapolated to predict the suitability of other unsampled regions. The value of many models would be increased by considering larger-scale processes that might be structuring spatial patterns across species distributions. We examined home-range habitat selection by burrowing owls throughout the mixed prairie grassland region of western Canada (180,000km2) to determine whether owl selection for biotic factors changes along abiotic gradients. Specifically, we classified 37 explanatory variables into five categories (geography, grassland fragmentation, land-use, soil, and climate), created models for each set of variables, and evaluated the predictive ability of each model. We then examined interaction effects to determine if the relationship between land cover variables and the probability of owl home-range selection varied within large-scale abiotic criteria. Our results showed that soil and climate produce the most predictive models of burrowing owl home-range selection and create unique environmental conditions for owls which are independent of land cover at this scale. This study provides new insight into burrowing owl habitat requirements, and strengthens the case for considering large-scale abiotic gradients when prioritizing areas for species conservation. [Copyright &y& Elsevier]

Abstract: For most carnivore populations, territoriality is the regulating social system ultimately determined by food abundance and/or strife. However, in some food-based territorial felid species such as the jaguar (Panthera onca), the influence of food availability on territoriality remains unclear and may be lessened because of a tendency for individuals to occur at high densities across the landscape. We examined spatial organization and use of food in a population of jaguars in the southern region of the Pantanal, Brazil (2003–04). We predicted that if territoriality plays an important role in determining jaguar population dynamics, exclusive use of territories should be observed and thereby influence prey selection patterns. We determined that home range sizes were comparable between sexes and overlapped little at the core area level. Line transect surveys revealed that large mammals comprised the bulk of available wild prey for jaguars, and scat analysis indicated that jaguars relied mostly on large mammalian prey. The most common wild species killed by jaguars were capybara (Hydrochaeris hydrochaeris) and caiman (Caiman yacare). We estimated that the wild prey base was adequate to support the jaguar population. Larger wild prey species were considerably more likely to die from predation than from other causes, and predation was more likely to occur in jaguar core areas than in areas of home range overlap. Modest cattle depredation rates had little demographic importance to the local jaguar population. We conclude that spacing patterns in the local jaguar population were likely based on exclusion through territoriality rather than food limitation. [Copyright &y& Elsevier]

We monitored the survival, dispersal, and home-range establishment of captive-bred, reintroduced puaiohi Myadestes palmeri, a critically endangered thrush endemic to the island of Kauai. Fourteen captive-bred, juvenile birds were released from hacktowers in January–February 1999 and monitored for 8–10 weeks using radiotelemetry. All 14 birds (100%) survived to 56 days post-release. Two birds (14.3%) dispersed greater than 3 km from release site within 1 day of release. The remaining birds settled within 1 week and established either temporary home-ranges (mean area=7.9±12.0 ha, range 0.4–31.9) or breeding home-ranges (mean area 1.2±0.34 ha, range 0.8–1.6). Temporary home ranges were abandonded by the beginning of the breeding season, and ultimately 6 of the 14 birds (43%) established breeding home ranges in the release area. The high survival rate bodes well for establishing additional populations through captive breeding and release; however, the 57% dispersal rate out of the target area means that several releases of birds may be necessary in order to repopulate a given drainage. Furthermore, observed dispersal and gene flow between the reintroduced and wild populations have important implications for management of the captive flock. [Copyright &y& Elsevier]