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Space use is a fundamental characteristic that informs our knowledge of social relationships and the degree to which individuals are territorial. Until recently, relatively little was known about the spatial ecology and social organization of swift foxes (Vulpes velox (Say, 1823)). We investigated space use of swift foxes on shortgrass prairie in northeastern Colorado. Our first objective was to evaluate sizes of seasonal and annual home ranges and core areas of 13 radio-collared swift foxes monitored continuously for 2 years. Our second objective was to compare home-range and core-area overlap of breeding pairs to that of neighboring foxes, including male-male, female-female, and nonbreeding female-male dyads. Home-range size in our study population was among the smallest previously reported for swift foxes. Males tended to have slightly larger home ranges and core areas than females, and home-range size was significantly larger in the breeding season than in both the pup-rearing and the dispersal seasons; sizes of core areas did not differ seasonally. Spatial overlap between breeding pairs was substantial, whereas spatial overlap between neighbors, particularly males, was low, suggesting territoriality. Key words: Vulpes velox, home range, core area, seasonal, overlap, territoriality. L'utilisation de l'espace est une caracteristique fondamentale qui permet de connaitre les relations sociales et l'importance de la territorialite chez les individus. Jusqu'a recemment, on savait relativement peu de choses sur l'ecologie spatiale et l'organisation sociale des renards veloces (Vulpes velox (Say, 1823)). Nous avons etudie l'utilisation de l'espace chez les renards veloces dans la prairie d'herbes courtes du nord-est du Colorado. Notre premier objectif etait d'evaluer les domaines vitaux saisonniers et annuels et les aires centrales de 13 renards veloces porteurs de colliers radio suivis continuellement pendant 2 annees. Notre second objectif etait de comparer le chevauchement des domaines vitaux et des aires centrales des couples reproducteurs a celui de renards voisins, incluant des dyades male-male, femelle-femelle et femelle-male non reproducteurs. La taille du domaine vital observe dans la population etudiee est parmi les plus petites jamais signalees chez le renard veloce. Les males ont tendance a posseder un domaine vital et une aire centrale plus etendus que ceux des femelles; la taille du domaine vital est significativement plus grande durant la saison de reproduction que durant les deux saisons d' elevage des petits et de dispersion. La taille des aires centrales ne varie pas en fonction de la saison. Le chevauchement spatial est considerable entre les couples reproducteurs, alors que le chevauchement spatial entre les voisins, particulierement les males, est faible, ce qui laisse croire a l'existence de territorialite. Mots-cles : Vulpes velox, domaine vital, aire centrale, saisons, chevauchement, territorialite. [Traduit par la Redaction], Introduction Space use is a fundamental behavioral and ecological characteristic that informs our knowledge of an animal's interactions with its environment, including relationships with others in the population and the [...]

Space use and movements of Canada lynx (Lynx canadensis) are difficult to study with very-high-frequency radiocollars. We deployed global positioning system (GPS) collars on 11 lynx in Minnesota to study their seasonal space-use patterns. We estimated home ranges with minimum-convex-polygon and fixed-kernel methods and estimated core areas with area/probability curves. Fixed-kernel home ranges of males (range = 29-522 [km.sup.2]) were significantly larger than those of females (range = 5-95 [km.sup.2]) annually and during the denning season. Some male lynx increased movements during March, the month most influenced by breeding activity. Lynx core areas were predicted by the 60% fixed-kernel isopleth in most seasons. The mean core-area size of males (range = 6-190 [km.sup.2]) was significantly larger than that of females (range = 1-19 [km.sup.2]) annually and during denning. Most female lynx were reproductive animals with reduced movements, whereas males often ranged widely between Minnesota and Ontario. Sensitivity analyses examining the effect of location frequency on home-range size suggest that the home-range sizes of breeding females are less sensitive to sample size than those of males. Longer periods between locations decreased home-range and core-area overlap relative to the home range estimated from daily locations. GPS collars improve our understanding of space use and movements by lynx by increasing the spatial extent and temporal frequency of monitoring and allowing home ranges to be estimated over short periods that are relevant to life-history characteristics. Key words: Canada lynx, core area, global positioning system, home range, Lynx canadensis, movements, telemetry

To control invasive species and prioritize limited resources, managers need information about population size to evaluate the current state of the problem, the trend in population growth through time, and to understand the potential magnitude of the problem in the absence of management actions. This information is critical for informing management actions and allocating resources. We used two national-scale data sets to estimate historical, current, and future potential population size of invasive wild pigs (Sus scrofa; hereafter wild pigs) in the United States. Between 1982 to present, the Southeastern Cooperative Wildlife Disease Study mapped the distribution of wild pigs in the United States. In addition, recent research has predicted potential population density of wild pigs across the United States by evaluating broad-scale landscape characteristics. We intersected these two data sets to estimate the population size of wild pigs in 1982, 1988, 2004, 2010, 2013, and 2016. In addition, we estimated potential population size if wild pigs were present at equilibrium conditions in all available habitat in each state. We demonstrate which states have experienced recent population growth of wild pigs and are predicted to experience the greatest population increase in the future without sufficient management actions and policy implementation. Regions in the western, northern, and northeastern United States contain no or few wild pig populations, but could potentially support large numbers of these animals if their populations become established. This information is useful in identifying regions at greatest risk if wild pigs become established, which can assist in prioritizing management actions aimed at controlling or eliminating this invasive species across broad to local scales. [ABSTRACT FROM AUTHOR]

Although mammalian carnivores are vulnerable to habitat fragmentation and require landscape connectivity, their global patterns of fragmentation and connectivity have not been examined. We use recently developed high-resolution habitat suitability models to conduct comparative analyses and to identify global hotspots of fragmentation and connectivity for the world's terrestrial carnivores. Species with less fragmentation (i.e. more interior high-quality habitat) had larger geographical ranges, a greater proportion of habitat within their range, greater habitat connectivity and a lower risk of extinction. Species with higher connectivity (i.e. less habitat isolation) also had a greater proportion of high-quality habitat, but had smaller, not larger, ranges, probably reflecting shorter distances between habitat patches for species with restricted distributions; such species were also more threatened, as would be expected given the negative relationship between range size and extinction risk. Fragmentation and connectivity did not differ among Carnivora families, and body mass was associated with connectivity but not fragmentation. On average, only 54.3 per cent of a species' geographical range comprised high-quality habitat, and more troubling, only 5.2 per cent of the range comprised such habitat within protected areas. Identification of global hotspots of fragmentation and connectivity will help guide strategic priorities for carnivore conservation.