The massive flooding and damage caused to streams and rivers in the region is expected to have a significant effect on salmon stocks for years to come.
A state of emergency has been declared in the Canadian province of British Columbia after a major storm earlier this week cut off road and rail links in the region.
The Canadian Department of Fisheries and Oceans is expected to have scientists on the ground at Island rivers and streams over the coming days to watch flows and assess impacts on the spawn.
Meanwhile, thousands of farm animals have died and many more remain trapped by the flood waters after the storm passed through the country’s most agriculturally intensive areas.
Some 18,000 people are yet to return to their homes after an “atmospheric river” – a long strip of moisture in the air that transports water from tropical areas towards the poles – dumped a month’s worth of rainfall in 24 hours.
Eggs swept away
According to a report in Victoria-based newspaper, Times Colonist, the fast running water likely swept away incubating eggs and sent young salmon prematurely out to sea, destroyed critical gravel nesting sites and food sources, and hindered salmon that had yet to spawn.
— Reuters (@Reuters) November 19, 2021
Ian Bruce, a biologist with the Peninsula Streams Society, who was assessing some of the damage caused by overflowing creeks and streams this week, said “It will affect a lot of fish.”
Bruce said the deluge this week washed away gravel beds containing incubating eggs, especially in areas where river banks have been altered for farming and development and the river can no longer spill its banks.
The Goldstream Hatchery in Langford has concerns the chum salmon run might have been wiped out.
Incubating eggs are being smothered in silt and debris. The hatchery’s fish fences and weir used to count fish and collect selected brood stock was completely submerged and weighed down by logs and debris. A hydrometer system used by the Capital Regional District to measure water flows was ripped off its foundation and deposited downstream.
Counting the cost
It had already been one of the lowest returns of chum on record, and the hatchery was only able to collect about 45,000 eggs. In other years, it has collected close to 600,000 eggs.
The Canadian Armed Forces have been deployed to help thousands of stranded residents who have been trapped since the storm hit overnight on Sunday.
As of Thursday, nearly 7,000 properties remained under mandatory evacuation orders, with more than 2,500 others under evacuation advisory.