Restoring native biodiversity within urban landscapes: A community restoration initiative to remove invasive species from an urban forest ecosystem in Esquimalt Gorge Park in Victoria, BC
AbstractUrbanization continuously threatens native biodiversity through natural habitat alteration, decreased connectivity between remnant native habitats, and the introduction of exotic species. Urbanization’s ongoing pressures on remnant natural environments makes ecological restoration critical for the conservation of urban biodiversity. The purpose of this study was to remove invasive species, specifically English ivy (Hedera helix) and Daphne laurel (Daphne laureola), from an urban forest within Esquimalt Gorge Park in Victoria, BC. Invasive species removal from the western margin of the forest would hopefully increase species diversity and reduce future invasive spread into adjacent invasive free areas. A thorough terrestrial biophysical inventory was conducted of the entire forest study site, which included identification of all plant species present on site and a 1x1m quadrant analysis to determine species ground cover abundance. Observations along ten alternating belt transects resulted in identification of 41 species; eight of which were non-native/invasive species. Most abundant species were English ivy (Hedera helix), grass (various species), and trailing blackberry (Rubus ursinus) and the most widely distributed species were English ivy (Hedera helix), Himalayan blackberry (Rubus armeniacus), grass (various species), Oregon beaked moss (Eurhynchium oreganum), and trailing blackberry (Rubus ursinus). Following the biophysical inventory, the treatment site was selected based on the highest densities of invasive species. A Community Restoration Event was developed and on March 11, 2018, 11 volunteers gathered to remove invasives from the marked 360m2 treatment site. Following the invasives removal, it is recommended that native plants be seeded and planted within the treatment site and repeated removal of invasives occur to minimize potential species regrowth. Revegetation and reseeding with native plant species, as well as repeated treatments, are all viable options moving forward with the continued partnership and support of the Township of Esquimalt and the Gorge Waterway Action Society.