Ecological Indicators (Oct 2023)
In search of evidence-based management targets: A synthesis of the effects of linear features on woodland caribou
Abstract
Effective species management relies on evidence-based goals that address the processes influencing population demography. These goals therefore require understanding how stressors affect the species of interest, and the food web within which the focal species is embedded. For woodland caribou, a conservation priority across much of its range, habitat loss and alteration is a primary cause of decline. Governments have identified maximum disturbance targets whereby a maximum of 35% total disturbance provides a 60% likelihood of self-sustaining caribou populations, but targets specific for linear features such as roads and seismic lines — which play a key role in altering ecological processes and are a primary focus for habitat restoration — have not been established. We created a framework to conceptually link stressors (linear features) to caribou declines via ecological mechanisms, and used this framework to guide a literature review to support the development of a linear feature-based management target for Southern Mountain Caribou. Despite the vast amount of research investigating the mechanisms leading to the negative relationship between caribou demography and linear features, our review of 54 peer-reviewed manuscripts and 99 grey-literature reports found little to no evidence of a threshold in these relationships in which to inform a linear feature-based management target for caribou population growth. Most studies evaluated how linear features modify space use of caribou, their predators, and the primary prey of those predators, whereas few mechanistically linked linear features to caribou demography. Our work provides a foundation in which other systems can conceptualize how stressors are linked to species declines, and to support the development of evidence-based management goals.
