Restoration of salmon to Lyall Creek (Gulf Islands National Park Reserve)
Project lead: Parks Canada
Key partners: (see list below)
Location: Gulf Islands National Park Reserve
Natural region: Strait of Georgia Lowlands (see National Park System Plan description)
Ecozone: Pacific Maritime
Timeframe: 2003 to 2006
Project size: 4 km of creek length
Project overview - Natural and cultural heritage values - Defining the problem - Goals and objectives - Project activities - Monitoring - Lessons learned - What’s next? - For more information - Contacts - Key partners
Parks Canada was a partner in the ecological restoration of the Lyall Creek ecosystem on Saturna Island in the Gulf Islands National Park Reserve. The project focused on re-establishing a chum salmon (Oncorhynchus keta) population in Lyall Creek, as well as improving conditions for coho salmon (Oncorhynchus kisutch) and coastal cutthroat trout (Oncorhynchus clarkia clarkii). A small culvert that had blocked upstream migration of salmon was removed and replaced with a larger concrete box culvert. This was followed by restoration of the creek's spawning and riparian (stream bank) habitats. Results of monitoring indicate good numbers of salmon returning to spawn. The Saturna Island community initiated the project in the 1990s, and has remained very engaged. Staff from Parks Canada became involved in 2003 when Gulf Islands National Park Reserve was established.
- effective in restoring and maintaining ecological integrity,
- efficient in using practical and economic methods to achieve functional success, and
- engaging through implementing inclusive processes and by recognizing and embracing interrelationships between culture and nature.
Natural and cultural heritage values
Lyall Creek is recognized as a significant ecosystem within the Gulf Islands National Park Reserve and is the only protected salmon-bearing watershed in the southern Gulf Islands, British Columbia. The surrounding riparian forest bears lush vegetation and supports a diversity of organisms including the red-legged frog, listed under the federal Species at Risk Act as a species of Special Concern (i.e., it could become a threatened or endangered species owing to a combination of biological characteristics and identified threats).
Defining the problem
In the 1970s, a collapsing log bridge over Lyall Creek was rebuilt with a small culvert, which proved to be an obstacle for chum salmon, one of three salmon species found in Lyall Creek. This species is the least successful at jumping over waterfalls and other impediments when returning to the creek to spawn; therefore, their spawning numbers declined. In addition, the culvert restricted peak flows and caused much greater than normal flooding and sediment deposition upstream of the bridge. As a result, the spawning habitat deteriorated for all three salmon species as the gravel stream bed was covered with sediment.
Goals and objectives
In the 1990s, a local group of residents called the Lyall Creek Enhancement Society began a chum fry stocking program, in partnership with Fisheries and Oceans Canada, to re-establish a chum salmon population in the creek. While their efforts were successful, the adult salmon returning to spawn still needed help from the residents to move upstream past the culvert. When Gulf Islands National Park Reserve was established in 2003, Parks Canada added additional scope to this project through its interest in studying, evaluating, and protecting the rare and sensitive features of Lyall Creek. The salmon stocking program needed to be enhanced through restoration of the hydrological and biological functions of the watershed. The goal was to restore the habitat and fish populations in hopes that they would become self-sustaining over the long term.
The Environmental Assessment (EA) process helped identify work practices and mitigation measures so that work involving heavy equipment could be undertaken in sensitive stream habitats without causing adverse environmental effects. A Section 9 permit under the Fisheries Act was also required to alter fish habitat.
Restoration started with the replacement of the two-metre steel culvert, which was an impediment for chum salmon passage. A larger, three-metre, pre-cast concrete box culvert would allow this species to migrate upstream to their spawning areas.
After the culvert was replaced, the creek bed was excavated to its original depth by removing approximately 800 cubic metres of sediment over a stream length of 200 metres. The original streambed re-surfaced 1.2 metres below the impounded creek elevation – representing 40 years of sediment deposition.
Several steps were taken to restore the structural complexity and hydrological regime (variations in the water cycle) of the creek. Approximately 40 cubic metres of boulders, cobble and spawning gravel were installed. This was followed by installation of over 20 large logs and root wads in the banks of the creek.
Re-grading and re-vegetation of the stream banks allowed for seasonal spill-over and flooding at normal levels.
Before restoration began, baseline survey data were collected to identify restoration priorities and long-term monitoring goals. These data have tremendous value not only as baseline inventory but also as the framework for other projects and for site interpretation. Riparian data can be integrated with other data to provide a full model of the basin.
To prevent accidental spread of invasive species, all large woody debris and structures were collected locally and cleaned prior to placement.
Logistics alone were a considerable accomplishment on Saturna Island, involving coordination with BC Ferries and all utility suppliers (telephone, hydro, fire service, ambulance, etc.) for deployment of an 80 tonne crane and excavation of the only vehicle access road across the island.
The restoration of Lyall Creek was initiated by the local community on Saturna Island. In the 1990s, the Lyall Creek Enhancement Society, in partnership with the Department of Fisheries and Oceans, obtained salmon eggs from a hatchery on Vancouver Island and grew them using in-stream incubation boxes. The young salmon were released into the creek each spring.
In 2005, the incubation program was replaced by a fry release program, which allowed local residents to work directly with hatchery staff. In addition, Saturna Island Elementary School initiated an annual project to raise salmon eggs and release the fry into the creek in the spring.
Various groups worked in partnership to restore the biological and hydrological functions of the creek’s watershed. In addition to the Lyall Creek Enhancement Society and the Department of Fisheries and Oceans, project work also included the British Columbia Ministry of Environment, British Columbia Ministry of Transportation and Highways, and the support of local volunteers and neighbours.
Information obtained from ongoing monitoring programs will assist the park in management of this watercourse. A detailed habitat inventory and monitoring program was implemented for the creek and riparian areas, including low water juvenile salmon surveys, reptile and amphibian inventories, groundwater monitoring and vegetation surveys. More formal assessment and reporting structures such as Environmental assessment and State of the park reporting also help monitor the outcome of the restoration. (Learn more about Monitoring in national parks) Juvenile salmon numbers indicate that the restoration efforts have resulted in increases in all salmon species. Based on salmon biomass, this small creek has become one of the highest production creeks, for its size, in the region.
- Restoration in complex landscapes can be challenging and costly.
- The challenges in this landscape were offset by the dedication, energy and knowledge of the local community.
- It is essential to learn by doing. Be able to adapt to changing circumstances and expanding knowledge.
- You need clear objectives with measurable outcomes; the technical work follows easily once the objectives are clear.
- Although it seems invasive to use heavy equipment, a good equipment operator can work wonders.
- Taking action is easy, but long-term commitment to monitoring is often more challenging.
As Lyall Creek continues to recover, follow-up work will be adapted to assist in the process. In addition, long-term monitoring will help determine where future work is required.
For more information
These case studies are intended to provide general information about ecological restoration projects. For more detailed or technical information, please consult the following sources or the contacts provided below.
- Gulf Island National Park Reserve of Canada
- The Lyall Creek Story: Gulf Islands National Park Reserve of Canada
- The Salmon Species of Lyall Creek
- Saturna Island
- Ecological research and monitoring in Gulf Islands National Park Reserve
For more detailed or technical information about this restoration project, please contact:
Tara Sharma, Ecologist Team Leader
Gulf Islands National Park Reserve
2220 Harbour Road
Sidney BC V8L 2P8
- BC Ministry of Environment
- BC Ministry of Transportation and Infrastructure
- Fisheries and Oceans Canada, Stewardship and Community Involvement Program
- Lyall Creek Enhancement Society
- Lyall Creek Stewardship Group
- Residents of Saturna Island
If you wish to comment on this case study, please contact Parks Canada at email@example.com