Drivers of change in the temperate-boreal refugium of Cape Breton Highlands National Park

Kosick, Hannah (2023) Drivers of change in the temperate-boreal refugium of Cape Breton Highlands National Park. Masters thesis, Memorial University of Newfoundland.

[English] PDF - Accepted Version Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Download (11MB)

Abstract

The Acadian-Maritime boreal ecotone of Cape Breton Highlands National Park contains low-elevation temperate species (Wabanaki-Acadian forest), and isolated patches of highland boreal stands at their northern and southern geographic extremes, respectively. The cumulative effects of moose herbivory, continued warming, and an imminent spruce budworm outbreak are expected to increase ecological pressures on the boreal forest, further isolating at-risk species. In addition to these stressors, climate change could induce range shifts of Acadian forests, constraining boreal species distributions. Our study identified if/where Acadian forest range shifts are occurring, examined if moose constrain species expansion, and assessed the availability of species-specific seedbeds. Despite the potential for Acadian range expansion, we did not find evidence of range shifts. Our findings suggest multiple constraints on Acadian forest range expansion, including moose herbivory and lack of suitable Acadian seedbeds at higher altitudes. We observed red maple (Acer rubrum) succession at moose meadows (historic boreal habitat), indicating persistent transitional stages of the boreal forest. Although range shifts have yet to occur, red maple success at moose meadow sites could facilitate Acadian forest expansion if herbivory pressures are reduced. Our research contributes to understanding Acadian-boreal forest dynamics at geographic extremes and establishes a foundation for long-term monitoring.

Actions (login required)

View Item