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• Restoring seismic lines is a priority for caribou conservation efforts. • We linked seismic line characteristics to vegetation composition and growth. • Wet seismic lines adjacent to open stands had more cover of wildlife forage. • Maps of vegetation cover and growth could be used to target seismic line restoration. • Restoration should target the proximate and ultimate causes of caribou decline. Linear disturbances impact ecosystems and species worldwide. These impacts are perhaps most profound in forest ecosystems like the Canadian boreal forest which has been fragmented by an extensive network of seismic lines which affect a number of boreal species. Of particular concern are the impacts of seismic lines on boreal and mountain woodland caribou (Rangifer tarandus caribou), which are declining across Canada primarily because of an increase in anthropogenic habitat disturbance including seismic lines, within their ranges. Restoring seismic lines is a focus of conservation efforts for caribou, however their extensive footprint implies that restoration efforts will need to be prioritized to target the ultimate (habitat disturbance, early seral stage vegetation), and proximate (wolf predation) causes of caribou declines. To help inform restoration efforts we used field data collected in 2014 and 2015 from 291 seismic lines in west-central and north-western Alberta, Canada, and GIS-derived and remote sensing (LiDAR) data to model and map vegetation recovery (growth, structure, and composition) on seismic lines and along seismic line edges. Although we found differences among regions and taxa, generally we found that wet seismic lines and seismic lines adjacent to open forest stands were more likely to have more early seral stage vegetation that is attractive wildlife forage. We also found that in west-central Alberta, wet seismic lines had less vegetation growth and cover, while in north-western Alberta, wet seismic lines were more likely to have more vegetation cover, but there was no relationship between vegetation growth on seismic lines and seismic line wetness. Using field data we predicted that vegetation on seismic lines within our study area had grown between 1 and 2 m between 2007 and 2015; however as our models of vegetation growth did not validate well other techniques (e.g. UAVs) and studies focused at smaller scales are likely to provide accurate data on current vegetation height and cover on seismic lines. Our results combined with results from previous research provide further evidence that seismic lines, particularly wet seismic lines, need active restoration to re-establish natural vegetation trajectories. Overall, targeting seismic line restoration treatments to change vegetation composition, as well as structure and height, will likely help to restore ecosystem function for caribou and other boreal species. [ABSTRACT FROM AUTHOR]

• Mountain Pine Beetle (MPB) and MPB control methods affect the abundance of plant-foods important to threatened caribou and grizzly bear populations in Alberta, Canada. • Many plant-food taxa had positive responses to MPB and/or fire, indicating adaptation to these natural disturbances. • Less-intensive MPB control and prescribed fires might be effective management options which balance the threat of MPB to forestry operations while maintaining food resources for threatened grizzly bear and caribou populations. In Alberta, Canada, mountain pine beetle (MPB) infestations overlap with threatened caribou and grizzly bear ranges. While MPB is a natural part of the ecosystem, increased intensity of infestation due to fire suppression and a changing climate has required mitigating actions in the form of MPB control treatments, including accelerated forest harvesting, prescribed burns, and single-tree cut and burn. However, little is known on how MPB and MPB treatments affect understory shrub and forb forage taxa important to threatened caribou and grizzly bear populations. Using data collected in west-central and north-west Alberta, we investigated how the occurrence and abundance of 25 shrub and forb taxa varied among MPB kill, MPB treatments: single-tree cut and burn, harvesting, fire, and uncut forest strata. We determined that MPB kill and MPB treatments impacted 13 forage taxa preferred by threatened caribou and grizzly bear populations. These caribou and grizzly bear forage taxa generally had a positive response to MPB kill and single-tree cut and burn, a positive response to fire, or a positive response to MPB kill, single-tree cut and burn, and fire. Our results suggest that less-intensive MPB treatments like single-tree cut and burn might balance the threat of MPB against maintaining food resources and habitat for threatened species. As MPB continues to be a significant problem in Alberta and across the boreal forest, the results from our study, combined with ongoing assessments on the impact of MPB on wildlife species will provide essential information for evidence-based landscape management. [ABSTRACT FROM AUTHOR]

• Context for pipeline corridors as potential ecological sinks for wildlife populations. • Quantitative analysis of plant taxa foraged by woodland caribou and grizzly bear. • Species composition and cover varied between pipelines versus adjacent forest. • High cover of graminoids on pipeline corridors as compared to adjacent forest. • Prioritizing ecosites within caribou ranges may be a beneficial restoration strategy. The construction of pipeline rights-of-way (ROWs, hereafter 'pipeline') involves mechanical site clearing, which impacts soil and ground cover vegetation and has implications for forage availability and predation risk for threatened wildlife, including woodland caribou (Rangifer tarandus) and grizzly bear (Ursus arctos). However, there has been no quantitative evaluation of vegetation communities on open pipelines as compared to the adjacent intact forest. We compared the cover of ground vegetation by vegetation type, and the cover and composition for plant taxa known for their importance as woodland caribou and grizzly bear forage, between plots located on pipeline corridors, near the edge of the pipeline corridor, and in the adjacent undisturbed forest across six different boreal forest ecosite types in west-central and north-western Alberta, Canada. Pipeline corridors were characterized by higher total ground vegetation cover, and cover of low shrubs, lichens, bryophyte and of targeted forage species of low shrubs, bryophytes, and lichens. In contrast, pipelines had higher graminoid cover and cover of target forage species of tall shrubs and graminoids, as compared to adjacent forest. Despite the substantive differences in cover and composition of ground vegetation among the ecosite types, differences between pipelines and the adjacent forest were quite consistent, with a few exceptions. For instance, forb cover was higher in the adjacent forest compared with pipelines in shrubby ecosite types, but was similar across plot locations in other ecosites. Species composition also varied among ecosites and differed between the adjacent forest and on pipelines; with pipelines dominated by graminoids, particularly Carex species. Our results demonstrate that pipelines influence ground vegetation communities, and cover and composition of wildlife forage species, across the boreal forest landscapes of Alberta; we suggest this results in pipelines being a potential ecological sink for wildlife populations, including threatened caribou. To ensure pipelines can recover, restoration strategies that promote natural recovery or purposeful re-planting may be required to accelerate forest re-establishment and put inactive pipeline corridors within caribou ranges on a recovery trajectory. Our results suggest that ecosites can be used to prioritize pipelines where restoration or management actions may be the most beneficial. [ABSTRACT FROM AUTHOR]