The vast boreal biome plays an important role in the global carbon cycle but is experiencing particularly rapid climate warming, threatening the integrity of valued ecosystems and their component species. We developed a framework and taxonomy to identify climate‐change refugia potential in the North American boreal region, summarizing current knowledge regarding mechanisms, geographic distribution, and landscape indicators. While “terrain‐mediated” refugia will mostly be limited to coastal and mountain regions, the ecological inertia (resistance to external fluctuations) contained in some boreal ecosystems may provide more extensive buffering against climate change, resulting in “ecosystem‐protected” refugia. A notable example is boreal peatlands, which can retain high surface soil moisture and water tables even in the face of drought. Refugia from wildfire are also especially important in the boreal region, which is characterized by active disturbance regimes. Our framework will help identify areas of high refugia potential, and inform ecosystem management and conservation planning in light of climate change.

Disentangling the role of competition in regulating the distribution of sympatric species can be difficult because species can have different habitat preferences or time use that introduce non-random patterns that are not related to interspecific interactions. We adopted a multi-step approach to systematically incorporate habitat preferences while investigating the co-occurrence of two presumed competitors, morphologically similar, and closely related ground-dwelling birds: the brown tinamou (Crypturellus obsoletus) and the tataupa tinamou (C. tataupa). First, we used single-species occupancy models to identify the main landscape characteristics affecting site occupancy, while accounting for detection probability. We then used these factors to control for the effect of habitat while investigating species co-occurrence. In addition, we investigated species present-time partitioning by measuring the degree of overlap in their activity time. Both species were strictly diurnal and their activity time highly overlapped (i.e., the species are not present-time partitioning). The distribution of the two species varied across the landscape, and they seemed to occupy opposite portions of the study area, but co-occurrence models and species interaction factors suggested that the tinamous have independent occupancy and detection. In addition, co-occurrence models that accounted for habitat performed better than models without habitat covariates. The observed co-occurrence pattern is more likely related to habitat preferences, wherein species segregated by elevation. These results provide evidence that habitat characteristics can play a bigger role than interspecific interactions in regulating co-existence of some species. Therefore, exploring habitat preferences while analyzing co-occurrence patterns is essential, in addition to being a feasible approach to achieve more accurate estimation of parameters reflecting species interactions. Occupancy models can be a valuable tool in such modeling.

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Frugivores are key components of Neotropical forests, regulating plant communities, forest structure, and plant diversity; however, they are highly threatened by human impacts worldwide. To effectively conserve this group, maintain their ecological functions, and plan management actions or establish future protected areas, we need to gather information about their relationship with the landscape attributes. Here, we used camera traps and call surveys (April 2013 to March 2014) to estimate the occupancy of seven frugivores (a rodent, two ungulates, two primates and two ground-dwelling birds) at 45 sampling sites distributed within a protected area of Atlantic Forest (35 000 ha) in south-east Brazil. We evaluated the relative effects of anthropogenic landscape variables, environmental attributes and geomorphometry on their occupancy at multiple scales. To achieve this, we measured landscape metrics at three spatial scales (200, 500 and 1000 m) around each sampling site and used multi-season occupancy modeling. Factors related to human presence or disturbance, such as human accessibility, proximity to the reserve, and forest cover, were the main predictors of occupancy by frugivorous game species (paca -Cuniculus paca; brocket deer -Mazama sp.; and collared peccary -Pecari tajacu). Strictly environmental and geomorphometric variables were weaker determinants of frugivore occupancy. Our results also suggest that weather, season and habitat-related variables can equally influence animal detection probability. Moreover, different species of frugivores responded differently to landscape attributes, and their response depended on the spatial landscape scale at which they perceive their habitat. This highlights the importance of a multi-taxa and multi-scale approach when assessing species-habitat relationships and planning wildlife management actions. 520Animal Conservation 20 (2017) 520-531 ª

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