Integrating accessibility and intactness into large-area conservation planning in the Canadian boreal forest

- Integrates human accessibility and intactness within spatial conservation tools.
- Reserve compactness (i.e., reserve size) greatly influences reserve efficiency.
- Prioritizing only intact areas reduces reserve flexibility and efficiency.
- Accessibility cost surrogate enables the prioritization of remote areas.
- Approach is useful for aiding conservation planning at a boreal-wide scale.

The creation of large protected areas from naturally functioning ecosystems that are largely without anthropogenic activity is viewed as an important option for maintaining the persistence of biodiversity and for allowing natural ecological and evolutionary processes to continue. Using the Canadian boreal forest as a case study, we demonstrate how biological elements, intact forest landscapes (e.g., dominantly forested areas largely unaffected by recent anthropogenic disturbance); cost (e.g., area and accessibility), and size considerations can be incorporated within spatial conservation planning tools to propose and, following transparent criteria, prioritize potential conservation opportunities within the boreal. We explore the trade-offs between reserve size and different area-based representative targets for three scenarios, two of which preferentially prioritize areas without competing land use. Consistent with other findings, the level of compactness (i.e., reserve size) greatly influences the reserve efficiency. Priority areas restricted to only intact forest landscapes were less flexible and efficient, particularly as target and compactness level increased. Nevertheless, priority areas using accessibility (distance from road and human settlement) as a cost surrogate were able to satisfy a range of conservation targets and compactness levels while remaining remote from human influence. These findings indicate the abundant intact areas within the Canadian boreal provide suitable areas for conservation investment and that this coarse-scale approach is useful for aiding conservation planning.