FOR IMMEDIATE RELEASE: Restoring habitat for juvenile Chinook - an at risk species: Scientific monitoring informs restoration efforts in the Squamish River Estuary
(Squamish B.C., 2019-05-29) The Squamish River Watershed Society (SRWS) is currently leading the Central Estuary Restoration Project in partnership with Fisheries and Oceans Canada and Squamish Nation. Through this project the SRWS is monitoring how the Squamish River training berm, known locally as the Spit road, continues to impact juvenile Chinook salmon access, and habitat function in the Squamish River estuary. Visitors to the area this summer may notice scientific equipment installed at various locations throughout the estuary collecting data to inform habitat restoration measures.
The Squamish River training berm was built in the 1970s to ‘train’ the river to the west side of the valley, and allow for the development of a coal port in the central part of the estuary. This sparked public concern over the continued industrialization of Squamish’s waterfront, and initiated the Squamish Estuary Management Planning process to realize a balanced approach to waterfront development. While the coal port was not permitted, the river training berm remained effectively isolating the Squamish River from its estuary flood plain. Juvenile salmon emerging from the river systems spend their rearing life stage in the estuary, as they prepare for life at sea, and the brackish habitat quality of estuaries is realized by mixing of freshwater and marine environments. SRWS Executive Director Edith Tobe states:
“The Squamish River training berm is an industrial relic from the 1970s that continues to limit both fish access, and habitat function in the Squamish River Estuary, despite ongoing restoration over the last 20+years.”
Chinook salmon are considered to be an at-risk species on the South Coast according to Fisheries and Oceans Canada, and these same populations are a primary food source for the endangered Southern Resident Killer Whale population. By the mid-1970s less then 500 returning Chinook salmon spawners were being counted annually in the Squamish River, compared to counts of 15,000 in the 1950s. Starting in the 1990s a series of nine culverts were installed across the training berm to bring freshwater back to restored estuary channels, and provide fish access from the river to the estuary. In 2013 the SRWS embarked on a three-year study to assess if juvenile Chinook were accessing the estuary through the culverts as intended.
Between 2013 & 2016, 200 fish nets and traps were set, and despite extensive effort only 239 juvenile Chinook were found in the estuary. For comparison, an average of 135,000 juvenile Chinook annually emerged from the Cheakamus River during the three-year estuary study. The Cheakamus River is one of many large tributaries to the estuary, which suggests that the actual number of juvenile Chinook emerging from each of these rivers, and flushed by the training berm directly into the Howe Sound may be much higher.
In 2018 juvenile salmon were tagged with passive integrated transponder (PIT) tags, and tag receivers were placed on select culverts in the training berm. The PIT tagging results supported the finding that juvenile Chinook salmon are not accessing the estuary through the existing culverts. Building on ongoing fish sampling efforts, the SRWS has added acoustic telemetry monitoring to the 2019 program with receivers placed in the river and the estuary. Acoustic telemetry is the best available technology for tracking fish movement in estuaries, and will further inform restoration efforts.
If you see something new or different in the estuary this summer, there is a good chance it is part of SRWS’s scientific monitoring program. It could be pin sticking out of the marsh measuring sediment accretion, perhaps an acoustic receiver or pit tag reader measuring fish movement, or a Hester-Dendy trap collecting invertebrate samples as the tides rise and fall. All of the SRWS’s equipment is tagged with the society’s contact information, and the data that it collects is vital to the continued restoration of the estuary, and survival of Chinook salmon – an at-risk species.
The Squamish River Watershed Society (SRWS) is a registered, charitable environmental non-profit that , formed in 1998 and takes a holistic approach towards watershed management, examining the headwaters down to the estuary and into Howe Sound. We are a projects-based organization that engages in watershed restoration, education and outreach, community stewardship, and monitoring programs.
For more information please contact Kimberly Armour, Assistant Project Manager (email@example.com)
Comments are closed.