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Wildlife models focused solely on a single strong influence (e.g., habitat components, wildlife harvest) are limited in their ability to detect key mechanisms influencing population change. Instead, we propose integrated modeling in the context of cumulative effects assessment using multispecies population dynamics models linked to landscape‐climate simulation at large spatial and temporal scales. We developed an integrated landscape and population simulation model using ALCES Online as the model‐building platform, and the model accounted for key ecological components and relationships among moose (Alces alces), grey wolves (Canis lupus nubilus), and woodland caribou (Rangifer tarandus caribou) in northern Ontario, Canada. We simulated multiple scenarios over 5 decades (beginning 2020) to explore sensitivity to climate change and land use and assessed effects at multiple scales. The magnitude of effect and the relative importance of key factors (climate change, roads, and habitat) differed depending on the scale of assessment. Across the full extent of the study area (654,311km2 [ecozonal scale]), the caribou population declined by 26% largely because of climate change and associated predator‐prey response, which led to caribou range recession in the southern part of the study area. At the caribou range scale (108,378 km2), which focused on 2 herds in the northern part of the study area, climate change led to a 10% decline in the population and development led to an additional 7% decline. At the project scale (8,331 km2), which was focused more narrowly on the landscape surrounding 4 proposed mines, the caribou population declined by 29% largely in response to simulated development. Given that observed caribou population dynamics were sensitive to the cumulative effects of climate change, land use, interspecific interactions, and scale, insights from the analysis might not emerge under a less complex model. Our integrated modeling framework provides valuable support for broader regional assessments, including estimation of risk to caribou and Indigenous food security, and for developing and evaluating potential caribou recovery strategies. © 2021 The Wildlife Society.

Many boreal forest birds, including the Common Nighthawk and Eastern Whip-poor-will, have shown recent steep population declines. Both species are known to use clearcuts as habitat locally; however this relationship has not been tested at a landscape-scale. In this study I addressed the question: Are landscapes with more clearcut associated with higher occupancy of Common Nighthawk and Eastern Whip-poor-will? I selected 49 recent clearcuts (≤ 15 years old) of similar size and placed acoustic recorders on their edges. I measured the proportion of recent clearcut within multiple spatial extents around each bird sample site. I also measured the proportion of open wetland in the landscapes as a covariate. Occurrence of neither species was significantly affected by the proportion of clearcut in the surrounding landscape, at any of the tested spatial extents. However, Common Nighthawk occupancy was lower in landscapes with higher proportions of older (11-15years old) clearcuts, and for both species occupancy was higher in landscapes with higher proportions of open wetland, significantly so for Eastern Whippoor-will. I propose that these species nest on clearcut edges because they seem to be similar to other open habitat like wetland edges. However, clearcuts may not offer the same level of insect prey supply as offered in the open wetlands and therefore do not act as similar foraging habitat. Thus, clearcut edges may act as ecological traps, attracting birds to nest in areas of lower habitat quality. I demonstrated that local-scale habitat associations do not necessarily scale up to a landscape-scale. My results suggest that the conservation of open wetlands will be important for persistence of these boreal bird species. iv