Investigating the impact of habitat fragmentation on woodland caribou (Rangifer tarandus) in British Columbia

• Main Author: Armour, Claire
• Language: unknown
• Published: Borealis
• Subjects: Earth and Environmental Sciences; landscape ecology; woodland caribou; habitat quality; Carcross; Muskwa; Rangifer tarandus
• Online Access: https://doi.org/10.5683/SP3/QLNC07

The purpose of this project was to map varying qualities of woodland caribou habitat in BC and quantify fragmentation of different habitat classes between 1985 and 2018. Woodland caribou populations in British Columbia are in steep decline despite extensive intervention efforts by the BC and Canadian Governments. The main drivers behind woodland caribou decline are habitat loss and increased predation. Caribou rely on large, contiguous tracts of mature forest to forage for lichens in the winter, raise their young in the spring, and as protection from predation. Disturbances such as timber harvests, wildfires, and human development fragment these patches, and the young forests and open areas left behind draw deer and moose to the area, exposing caribou to predation. Linear features such as roads, power lines, pipelines, and recreational trails create additional corridors which are used by predators to more easily access caribou herds. By measuring forest fragmentation in caribou herd ranges using landscape metrics, I was able to determine how the landscape configuration and composition in several herd ranges have changed between 1985 and 2018 and compare it to the long-term population trends of those herds. Four herd ranges across British Columbia – Barkerville, Wells Gray, Muskwa, and Carcross – were assessed for road density and habitat suitability for the two time points using a habitat suitability model with slope, biogeoclimatic ecosystem classification (BEC) zone, land cover, and stand age as parameters. Using eight landscape metrics, I was able to quantify the extent of fragmentation between the time points. All herds experienced an increase in road density and overall loss of low and medium-quality habitat. Composition and configuration changes in the high-quality landscapes were variable and ultimately did not strongly correlate with long-term population trends. Integration of cervid habitat suitability was determined to be a critical area for further research.