The influence of clearcut harvesting on bird communities in an adjacent protected area in Nova Scotia: Implications for buffer implementation

Human activities adjacent to protected areas have been intensifying as human population grows, with protected areas in some regions effectively becoming islands within a sea of human development. Studies examining the effects of forest harvesting and deforestation on the biodiversity of adjacent protected areas have primarily focused on study areas within the tropics. Due to concerns about impacts of low-retention or clearcut harvesting on biodiversity in adjacent protected areas, the province of Nova Scotia implemented interim harvesting guidelines adjacent to all parks and protected areas in 2019. To examine the effectiveness of these guidelines, we designed a study to quantify the relative influence of previous clearcut harvesting immediately adjacent to Cloud Lake Wilderness Area based on changes in bird communities along transects beginning 100 m inside clearcuts and extending 300 m into the protected area. Ordinations revealed clear differences in the bird communities among transect points; clearcut and edge bird communities differed significantly from those 200 and 300 m inside the protected area and those 100 m inside the protected area comprised of a blend of species from the other 4 transect point locations. Overall species richness and many individual species abundances reflected this pattern as well - 13 species with clear responses across transect point locations were intermediate in abundance at sites 100 m into the protected area. The weight of evidence from our study supports other research showing that the zone of influence from clearcut harvesting on passerine birds in adjacent forest is at least 100 m for many species. These results suggest that a minimum harvesting and development buffer adjacent to protected areas of between 100 and 200 m would be a reasonable management approach if the objective is to minimize the effects of these activities on the bird communities within protected areas. To determine if a partial harvest within the buffer would maintain biodiversity within a protected area will require additional research that directly compares the influence of partial harvesting to no-harvest prescriptions on a variety of taxa. Additional studies in other protected areas that vary in size and have dissimilar landscape contexts, habitat conditions, and bird communities could provide further insight.