If you are completing a thru-hike, you will require some kind of bear resistant container in order to camp legally at any of Parks Canada’s random camping areas. Some hikers will choose an Ursack over a bear cannister due to the weight difference as it is approved by Parks Canada as a bear resistant container. It is recommended to bring a cannister or Ursack even in areas where it is not legally required to reduce your chances of a negative bear encounter.
If you are only staying at campsites where you know there are bear lockers, food storage poles, or cables, you do not need a bear cannister. However, there is not a complete section of the GDT where this is possible – only for shorter hikes within the national parks such as the Rockwall Trail or Skyline Trail.