Bird-assisted Restoration Using Snags at Grand Manan Island Migratory Bird Sanctuary

  • Courtney J. Cameron University of Victoria


The Nature Conservancy of Canada (NCC) is starting a multi-phase restoration project on their Grand Manan Island, New Brunswick conservation property. This report describes a component of the restoration which aims to expedite succession through avian seed vectors, by erecting snags on the site that will serve as bird perches and wildlife trees. NCC site restoration goals include improving ecological value of the degraded former homestead, farm, and gravel quarry; this bird-snag component aims to connect restoration efforts to the site’s status as a Migratory Bird Sanctuary and Important Bird Area. The site is part of the Fundy Coastal Ecodistrict within the Atlantic Martitime Ecozone. Through previous site inventory, ecosystems surrounding the gravel quarry were classified as Alder Thicket, Lowland Barrens, and Wet Coniferous forest. Barren, soil-stripped portions of the site would have supported coastal spruce-fir (Picea-Abies) forests. Field work took place between September 2022 and March 2024 and included spatial/gap assessment to inform snag placement, site vegetation and bird surveys, snag installation, and monitoring set up through baseline inventory. Within the old gravel quarry, vegetation structure was found to range from Sparse-cryptogam to Shrub/Herb; tiny tamarack (Larix laricina), balsam fir (Abies balsamea), and spruce (Picea sp) trees are scattered in with shrubs like white meadowsweet (Spiraea alba) and herbaceous grasses and goldenrod (Solidago sp); terrain texture within the quarry comprises angular shale, rubble, and gravel and lacks soil structure. Six whole trees (two balsam fir, two tamarack, and two spruce) were transported to the site and planted with the help of machinery in open areas of the quarry; these are meant to decay and effectively serve as wildlife tree snags. Measuring from 7.2-9.1 metres tall, the snags are beacon-like within the area. Fifty-six bird species were observed at the conservation property during field work surveys; of those, at least 27 species were observed within or near the edges of the quarry, and 3 species were observed landing on the snags after installation, including Northern Flicker (Colaptes auratus). Citizen science data (eBird) has recorded a total of 184 species visiting the site (year-round, all years). In order to boost the probability that birds’ seed rain might help plant vegetation under that snags, Coarse Woody Debris was scattered underneath, and forest topsoil was spread around three of the snags. Long-term monitoring will include photopoint monitoring, vegetation surveys in 5-metre radius circle plots around each snag, and bird surveys. Adaptive management recommendations include options for adding more CWD around the snags, and planting shrub islands, specifically native berry-producing shrubs that could attract more birds.

Technical Papers