Modelling connectivity of boreal forest across Unama'ki (Cape Breton, Nova Scotia) to inform conservation and restoration efforts
Forests in Unama’ki (Cape Breton, Nova Scotia) have undergone significant changes in recent decades. Boreal forest succession in Unama’ki is largely influenced by naturally-occurring cyclical spruce budworm (Choristoneura fumiferana (Clemens)) outbreaks which defoliate and kill trees (Franklin et al., 2015). The most severe outbreak of spruce budworm was seen in the late 1970s (Ostaff & MacLean, 1989). Followed by an increase in moose populations, heavy moose browse prevented boreal forest in several areas of Unama’ki from regenerating, which have since converted to grasslands (Franklin et al., 2015; Smith, 2007). In addition to spruce budworm and heavy moose browse, the landscape is further impacted due to forestry. The integrity and connectivity of forests are invaluable for biodiversity, habitat, carbon sequestration and water cycle regulation. Ecological connectivity is the ability of a landscape to support the movement of species and ecological processes. The era of Anthropocene has witnessed mass, rapid changes in landcover and maintaining landscape connectivity is a major concern. Quantifying connectivity is therefore an important component in guiding protected area planning, habitat restoration and resource extraction (Hilty et al., 2019). This research seeks to quantify where and at what time forests loss or conversion has occurred throughout the northwest arm of Unama’ki. I am using forest cover data produced by Cape Breton Highlands National Park (CBHNP) from Landsat imagery at 30m resolution, at incremental time steps (1972, 1989, 1999, 2009, 2019), prior to and after the spruce budworm outbreak of the 1970s. I have quantified the loss of forest area and change in average patch size and boundary length at each time step both within and outside of CBHNP. Further, using Zonation software I have produced a model of structural connectivity of coniferous-dominant forests at each time step. An understanding of where forest loss has occurred and where connectivity has diminished over time will highlight areas of high priority for restoration. CBHNP will use these findings to guide their restoration and tree planting program within the national park. Future protected area planning and extraction activities will also benefit from this understanding of landscape connectivity. Preserving forest connectivity in Unama’ki will prove necessary in mitigating the impacts of climate change and future resource extraction.