Abstract

In the Pacific Northwest, land and resource managers strive to make decisions that benefit both natural and human communities, balancing ecological and economic demands including wildlife habitat, forest products, forage for grazing, clean water, and wildfire control. Climate change adds a layer of complexity to the planning process because of its uncertain effects on the environment. In order to make sound decisions, managers need information about how climate change will affect wildlife habitat, both on its own and in conjunction with management actions.

The goal of this project was to explore how future climate may interact with management alternatives to shape wildlife habitat across large landscapes. Scientists used computer simulations to investigate a range of future climate and management scenarios, focusing on habitat for two iconic species: the northern spotted owl and the greater sage-grouse.

Findings show that increasing wildfire is likely to be the primary threat to owl habitat as a result of climate change. Management actions that reduce the amount of vegetation available as fuel may be helpful at counteracting this threat, at least in southwestern Oregon. In the case of the greater sage-grouse, expected increases in wildfire may actually be helpful for managers, as they help to control the spread of juniper. However, invasive grasses are poised to overtake much of the landscape, creating a new management challenge.While the task of managing habitat in the face of climate change is daunting, this research yielded information that may be useful for setting management priorities and developing strategies that sustain these landscapes for both humans and wildlife.

This study addressed the challenges faced by natural resource management planning in the context of climate change. We explored how future climate may interact with management alternatives to shape wildlife habitat across large landscapes. We studied habitat for the northern spotted owl in coastal Washington and southwestern Oregon, and habitat for the greater sage-grouse in southeastern Oregon.

In coastal Washington, the primary threat to owl habitat is likely to be habitat loss as a result of increasing fire and shifts in vegetation with changing climate. These threats may not be fully mitigated with management. In southwest Oregon, increasing fire frequencies under climate change are also likely to pose the greatest threat to owl habitat. Management aimed at constraining fires is needed, but due to the scope of the problem, strategic fuel treatment management will be vital.

In southeast Oregon, some threats to sage-grouse habitat are more manageable than others. Wildfire increased under all climate scenarios. Climatic constraints to sage-grouse from hotter, drier summers cannot be managed, but some effects of climate change may aid the goals of management. For instance, increasing fire frequency can help control juniper expansion. Unfortunately, invasive annual grasses are poised to invade much of the landscape at a rate that could exceed the capacity of management.

While the task of maintaining and enhancing habitat across large, complicated landscapes in the face of climate change is daunting, this research yields information that is useful in setting management priorities and developing strategies for maintaining habitat and addressing other major goals in all three regions.