Search Results (5)

Cumulative effects of increased forest harvesting, mountain pine beetle (Dendroctonus ponderosae; MPB) outbreaks, and wildfire in low-elevation lodgepole pine (Pinus contorta) forests could limit long-term winter habitat supply for the northern group of southern mountain caribou (Rangifer tarandus). In a 17 year longitudinal study of vegetation remeasurements at eight sites in north-central and west-central British Columbia (BC), we assessed responses of terrestrial caribou forage lichen abundances to nine forest harvesting treatments and one prescribed burn 8–14 years following treatment, as well as to MPB attack. Overall, after initially declining following forest harvesting, mean forage lichen abundance increased between 1 and 2 years post-harvest and 13 and 14 years post-harvest at 10 of 11 site/treatment combinations. Mean forage lichen abundance decreased following MPB attack at all sites. Biophysical factors influencing rates of lichen recovery post-disturbance include site type (transitional vs. edaphic), a reduction in favourable conditions for moss recovery, level of MPB attack, and both seasonal timing and method of forest harvesting. When considering effects of forest harvesting on forage lichens, objectives of silvicultural management strategies should focus on protecting and retaining terrestrial lichens at edaphic sites and on re-establishing terrestrial lichens at transitional sites. Full article

The Moose Horn Pass Caribou Fence site (KjRx-1) consists of three wooden fences located in a remote area of the Mackenzie Mountains in Canada’s Northwest Territories. Situated in the traditional homeland of the Shúhtagot’ine (Mountain Dene), they were used to assist past hunters to harvest northern mountain caribou by channeling multiple animals toward kill zones. The main fence is nearly 800 m in length and terminates in a corral structure after descending from high ground into a valley. The two smaller fences are located north and south of the main fence, and they do not descend into the valley. Standard dendrochronological methods were employed to determine the ages of wood taken from the fence structures. Seventy-five living white spruce (Picea glauca) trees in the area were cored to determine the overall tree-ring growth patterns in the local environment. The chronology of living trees was supplemented by the inclusion of 29 standing-dead trees to establish a longer chronology of dated ring widths. Sixty-two of 89 cross-sections cut from the fence timbers were crossdated and added to the overall chronology, which created a well-replicated chronology of ring-widths from 972 to 2016 C.E. The terminal dates of material from the three fence systems suggest that the complex was built from trees that died over a wide temporal period, spanning the years 1314 to 1876 C.E, with clusters of dates between ca. 1420–1480 and 1580–1750 C.E. The millennial-long chronology developed in this study can now be used as a base to assist in dendroarchaeological dating of many more artifacts from the region. Full article

Northern protected areas guard against habitat and species loss but are themselves highly vulnerable to environmental change due to their fixed spatial boundaries. In the low Arctic, Torngat Mountains National Park (TMNP) of Canada, widespread greening has recently occurred alongside warming temperatures and regional declines in caribou. Little is known, however, about how biophysical controls mediate plant responses to climate warming, and available observational data are limited in temporal and spatial scope. In this study, we investigated the drivers of land cover change for the 9700 km² extent of the park using satellite remote sensing and geostatistical modelling. Random forest classification was used to hindcast and simulate land cover change for four different land cover types from 1985 to 2019 with topographic and surface reflectance imagery (Landsat archive). The resulting land cover maps, in addition to topographic and biotic variables, were then used to predict where future shrub expansion is likely to occur using a binomial regression framework. Land cover hindcasts showed a 235% increase in shrub and a 105% increase in wet vegetation cover from 1985/89 to 2015/19. Shrub cover was highly persistent and displaced wet vegetation in southern, low-elevation areas, whereas wet vegetation expanded to formerly dry, mid-elevations. The predictive model identified both biotic (initial cover class, number of surrounding shrub neighbors), and topographic variables (elevation, latitude, and distance to the coast) as strong predictors of future shrub expansion. A further 51% increase in shrub cover is expected by 2039/43 relative to 2014 reference data. Establishing long-term monitoring plots within TMNP in areas where rapid vegetation change is predicted to occur will help to validate remote sensing observations and will improve our understanding of the consequences of change for biotic and abiotic components of the tundra ecosystem, including important cultural keystone species. Full article

Across Inuit Nunangat, Inuit rely on wildlife for food security, cultural continuity, intergenerational learning, and livelihoods. Caribou has been an essential species for Inuit for millennia, providing food, clothing, significant cultural practices, and knowledge-sharing. Current declines in many caribou populations—often coupled with hunting moratoriums—have significant impacts on Inuit food, culture, livelihoods, and well-being. Following an Inuit-led approach, this study characterized Inuit-caribou relationships; explored Inuit perspectives on how caribou have been managed; and identified opportunities for sustaining the Mealy Mountain Caribou. Qualitative data were collected in Rigolet, Nunatsiavut, Labrador, Canada through 21 in-depth interviews and two community open houses. Data were analyzed using constant comparative methods and thematic analysis. Rigolet Inuit described: how conservation management decisions had disrupted important connections among caribou and Inuit, particularly related to food, culture, and well-being; the socio-cultural and emotional impacts of the criminalization of an important cultural practice, as well as perceived inequities in wildlife conservation enforcement; and the frustration, anger, and hurt with not being heard or included in caribou management decisions. These results provide insights into experiences of historic and ongoing colonial wildlife management decisions, and highlight future directions for management initiatives for the health and well-being of Inuit and caribou. Full article

Pinus contorta-dominated montane forests of western Canada with relatively dense tree canopies have ground layers with abundant bryophytes, especially the feather mosses (Pleurozium schreberi and Hylocomium splendens), while those with more open canopies are dominated by species of reindeer lichens, especially Cladonia arbuscula s.l. and C. rangiferina s.l. Woodland caribou (Rangifer tarandus caribou), which are a threatened species in Alberta, prefer open, Cladonia-dominated forests for their winter food supply. This study investigated if opening the canopy by thinning mature montane forests of the Canadian Rocky Mountain foothills would change the abundance of lichens and bryophytes. In 1997, forests were thinned by removing 20%, 40%, and 60% by volume. In 2016, 19 years after treatment, we re-surveyed a subset of these plots (n = 97) for lichen and bryophyte abundance and species richness by utilizing the amount of canopy opening at the plot level as our prime gradient. We then used ordination to determine the relationship of control plots to treatment plots. In uncut forest, the control plots were highly variable, but were mostly dominated by feather mosses, with little or no bare ground. Feather moss abundance was lower in treatment plots when compared to control plots, while cover of bare ground was greater. Overall, 19 years after treatment, we found that, in treatment plots, lichen abundance remained stable or slightly increased, feather mosses decreased markedly, and unoccupied space was double that of the control plots. We conclude that the canopy opening had little effect on understory and ground layer diversity, but considering species abundance (1) bryophytes have not recovered after canopy opening, (2) populations of reindeer lichens increased marginally, but have not colonized areas left bare from bryophyte dieback, and (3), after 19 years there, remains unoccupied areas of bare ground in plots with a reduced canopy cover. Our study demonstrated that, with canopy cover reduction resulting from forest thinning operations, the ground layer diversity is maintained, but recovery of ground layers in old-growth pine-dominated forests is not promoted. Therefore, timber harvest that partially opens the tree canopy is unlikely to benefit caribou by augmenting or accelerating winter food availability and habitat suitability for caribou. Full article