If the drought didn’t kill the salmon, humans might
Goldstream Hatchery results were a mixed bag this year
Spawning salmon have had a hard year. They contended with the usual threats of the open ocean; fishing boats, predators, disease, and changing ocean conditions. And those who survived long enough to come home to spawn started swimming upstream only to find recklessly low water levels from the unseasonable hot and dry fall. Thousands of salmon suffocated on their way up streams on Vancouver Island.
Yet, the Goldstream Hatchery has one thing in its favour: its water is augmented with regular, controlled releases from the Capital Regional District reservoir. With that one variable eliminated, thousands more chum salmon returned than in an average year.
The official count hasn’t been published yet, but Peter McCully, a long-time technical advisor to the Goldstream Hatchery, said between 33,000 and 34,000 chum salmon made their way upstream—way above the 15,000 chum escapement target set by the Department of Fisheries and Oceans for Goldstream River. (Only after 15,000 chum have “escaped” into their spawning stream will DFO even think about allowing commercial or recreational fishing.)
Meanwhile, rivers and streams on Vancouver Island’s east coast had dismal chum spawning this year, according to McCully’s colleagues.
So does the above average return in the one river protected from drought mean the ocean conditions were in the chum’s favour?
That is a million dollar question for any salmon researcher. Last year’s chum returns were one of the lowest on record at the Goldstream Hatchery, so McCully said he can’t begin to suppose what caused this year to be so successful.
“It's one of those mysteries. We just don't have enough information about what's going on in the ocean,” he said.
It wasn’t a great year for all species of salmon at the hatchery, though.
Coho salmon returns were below average, but enough for the hatchery to collect their target number of eggs to be protected and released next year.
Chinook, however, are all but extirpated from the Goldstream water system. Also called spring salmon, or king salmon, Chinook are by far the largest of the genus. They weigh nine kilograms on average (for a lucky fisherman) compared to a 3.6 kg average for chum. If you’re fishing for a tyee (a salmon that weighs 13.6 kg (30 lbs) or more), it’s a Chinook you’re after.
Goldstream Hatchery counted no more than six Chinooks this year. For a river of Goldstream’s size, that means the tyee species is virtually gone, McCully said. There never was a large Chinook population in the Goldstream River, but the hatchery’s efforts had built up the population to a reasonably sustainable amount in the mid 1990s.
“Since then it's just been slowly picked away until it's virtually nothing,” he said.
Since Goldstream’s waterway is largely within provincial parks, the development that so often affects streams and spawning areas isn’t really a factor. Instead McCully points again to the ocean conditions we don’t know enough about, and one thing we can see plainly: an explosion of pinnipeds.
“The [Chinook] start coming back about August and they don't come into the river immediately because the river is pretty warm. So they're loitering off the mouth of the river and it only takes about 10 habituated seals, and they just really wreak havoc with them,” McCully said.
Humans and salmon compete for resources: ‘We don't play nice with salmon’
When chum salmon come up the Goldstream, they used to take a week or less to spawn and die (sorry if you didn’t know that; it’s all part of the cycle). But in the last few years McCully and his colleagues at the hatchery have observed chum salmon stay “in residence” for two weeks, sometimes more.
He suspects this behaviour change is a response to climate change, as the fish attempt to adjust to new conditions—or it could just be a blip on the horizon.
“That's what we're trying to figure out.”
Coho don’t seem to be staying longer, but then they already were staying for up to six weeks. They’re a totally different creature, McCully points out.
What all five Pacific salmon species have in common is something they also have in common with humans: the need for water and habitat.
“We don't play nice with salmon. We're in competition for the same resources that they need. Good, clean, cold water, and habitat: we're always in competition for that,” McCully said.
“If we're willing to make the sacrifices and spend a bit of extra money, we can coexist with these creatures, we really can.”
When students come to the hatchery for the salmon enrichment curriculum, McCully always asks them to think about ways to use less water—something he’d also like their parents to consider. Using clean water to hose down a driveway is a particular pet peeve of his.
Another easy thing to point to is our habit of using non-permeable surfaces, like concrete parking lots.
Rain that falls on soil (or other permeable surfaces) is slowly absorbed, filtered, and gradually seeps back out into lakes and streams. But rain on a non-permeable parking lot flows straight to the storm drain and into the water system, which causes irregular highs and lows in water levels and temperature, not to mention contamination.
“Let's be more concerned about the management of our resources,” McCully asks of us. “We can develop parking lots and hard surfaces that are permeable that the water can go through. It just takes a little bit more effort and a bit more money. I think most people are willing to accept those sorts of conditions if they understand.”