Ruthanne Henry

Natural green spaces provide many benefits to urban dwellers, but are vulnerable to the pressures of increasing use. Natural parklands are also prone to ecological degradation where operational and capital management are not minimizing impacts from increasing use. Approximately 7.2% of Toronto is natural parkland distributed throughout the city area. Since 1981 many of Toronto’s highest quality natural areas have been identified as Environmentally Significant Areas (ESAs) based on field inventories of flora, fauna and ecological functions. Unofficial trails have been established within these ESAs and more trails continue to be established by users of these areas and on other natural parkland. Dog walkers, hikers, off-road cyclists, as well as schools, camps and other recreational programs are the primary trail users. In this project, spatial analysis was used to evaluate the changes in core area habitat, or those areas outside the disturbance zone of trails, within four of Toronto’s priority ESAs.
Additionally, Vector based Landscape Analysis Tools (V-LATE) and ArcGIS software was used to both visualize and quantify changes to ESAs based upon future management scenarios. Results indicate that between 19 and 49% of high quality habitat (core areas) of these ESAs may be lost in the near future, (within the next 10-20 years) under a “no management” scenario where ad-hoc trails and existing uses progress unrestricted. The outcomes to ESAs resulting from a “no management” approach are contrasted with a scenario of “increased management” (e.g., restrictions on use, trail redesign and outreach to users). The discussion considers the results within a natural resource municipal decision-making framework. This research provides a parks planning precedent for other cities seeking to maintain ecological resilience within
urban natural areas under increasing recreational pressures.

Keywords: (6 listed alphabetically) Core Area, Ecological Degradation, Management, Recreation, Trails, Vector-based Landscape Analysis Tools (V-LATE)