Climate-informed forecasts reveal dramatic local habitat shifts and population uncertainty for northern boreal caribou.

Most research on boreal populations of woodland caribou (Rangifer tarandus caribou) has been conducted in areas of high anthropogenic disturbance. However, a large portion of the species' range overlaps relatively pristine areas primarily affected by natural disturbances, such as wildfire. Climate-driven habitat change is a key concern for the conservation of boreal-dependent species, where management decisions have yet to consider knowledge from multiple ecological domains integrated into a cohesive and spatially explicit forecast of species-specific habitat and demography. We used a novel ecological forecasting framework to provide climate-sensitive projections of habitat and demography for five boreal caribou monitoring areas within the Northwest Territories (NWT), Canada, over 90 years. Importantly, we quantify uncertainty around forecasted mean values. Our results suggest habitat suitability may increase in central and southwest regions of the NWT's Taiga Plains ecozone but decrease in southern and northwestern regions driven by conversion of coniferous to deciduous forests. We do not project that boreal caribou population growth rates will change despite forecasted changes to habitat suitability. Our results emphasize the importance of efforts to protect and restore northern boreal caribou habitat despite climate uncertainty while highlighting expected spatial variations that are important considerations for local people who rely on them. An ability to reproduce previous work, and critical thought when incorporating sources of uncertainty, will be important to refine forecasts, derive management decisions, and improve conservation efficacy for northern species at risk.

Accounting for system dynamics in reserve design.

Systematic conservation plans have only recently considered the dynamic nature of ecosystems. Methods have been developed to incorporate climate change, population dynamics, and uncertainty in reserve design, but few studies have examined how to account for natural disturbance. Considering natural disturbance in reserve design may be especially important for the world's remaining intact areas, which still experience active natural disturbance regimes. We developed a spatially explicit, dynamic simulation model, CONSERV, which simulates patch dynamics and fire, and used it to evaluate the efficacy of hypothetical reserve networks in northern Canada. We designed six networks based on conventional reserve design methods, with different conservation targets for woodland caribou habitat, high-quality wetlands, vegetation, water bodies, and relative connectedness. We input the six reserve networks into CONSERV and tracked the ability of each to maintain initial conservation targets through time under an active natural disturbance regime. None of the reserve networks maintained all initial targets, and some over-represented certain features, suggesting that both effectiveness and efficiency of reserve design could be improved through use of spatially explicit dynamic simulation during the planning process. Spatial simulation models of landscape dynamics are commonly used in natural resource management, but we provide the first illustration of their potential use for reserve design. Spatial simulation models could be used iteratively to evaluate competing reserve designs and select targets that have a higher likelihood of being maintained through time. Such models could be combined with dynamic planning techniques to develop a general theory for reserve design in an uncertain world.

Potential spatial overlap of heritage sites and protected areas in a boreal region of northern Canada.

Under article 8-J of the Convention on Biological Diversity, governments must engage indigenous and local communities in the designation and management of protected areas. A better understanding of the relationship between community heritage sites and sites identified to protect conventional conservation features could inform conservation-planning exercises on indigenous lands. We examined the potential overlap between Gwich'in First Nations' (Northwest Territories, Canada) heritage sites and areas independently identified for the protection of conventional conservation targets. We designed nine hypothetical protected-area networks with different targets for woodland caribou (Rangifer tarandus caribou) habitat, high-quality wetland areas, representative vegetation types, water bodies, environmentally significant area, territorial parks, and network aggregation. We compared the spatial overlap of heritage sites to these nine protected-area networks. The degree of spatial overlap (Jaccard similarity) between heritage sites and the protected-area networks with moderate or high aggregation was significantly higher (p < 0.001) than random spatial overlap, whereas the overlap between heritage sites and the protected-area networks with no aggregation was not significant or significantly lower (p < 0.001) than random spatial overlap. Our results suggest that protected-area networks designed to capture conventional conservation features may protect key heritage sites but only if the underlying characteristics of these sites are considered. The Gwich'in heritage sites are highly aggregated and only protected-area networks that had moderate and high aggregation had significant overlap with the heritage sites. We suggest that conventional conservation plans incorporate heritage sites into their design criteria to complement conventional conservation targets and effectively protect indigenous heritage sites.

Reconciling salvage logging of boreal forests with a tural-disturbance management model.

In North American boreal forests, wildfire is the dominant agent of natural disturbance. A natural-disturbance model has therefore been promoted as an ecologically based approach to forest harvesting in these systems. Given accelerating resource demands, fire competes with harvest for timber and there is increasing pressure to salvage naturally burned areas. This creates a management paradox: simultaneous promotion of natural disturbance as a guide to sustainability while salvaging forests that have been naturally disturbed. The major drivers of postfire salvage in Canadian boreal forests are societal perceptions, overallocation of forest resources, and economic and policy incentives, and postfire salvage compromisesforest sustainability by diminishing the role of fire as a critical, natural process. These factors might be reconciled through consideration of fire in resource allocations and application of active adaptive management. We provide novel treatment of the role of burn severity in mediating biotic response by examining its influence on the amount, type, and distribution of live, postfire residual material, and we highlight the role of fire in shaping spatial and temporal patterns in forest biodiversity. Maintenance of natural postfire forests is a critical component of an ecosystem-based approach to forest management in boreal systems. Nevertheless, presentpracticesfocus heavily on expediting removal of timber from burned forests, despite increasing evidence that postfire communities differ markedly from postharvest systems, and there is a mismatch between emerging management models and past management practices. Policies that recognize the critical role of fire in these systems and facilitate enhanced understanding of natural system dynamics in support of development of sustainable management practices are urgently needed.