Taking the upper Riverdale Trail is a casual, Sunday afternoon hike for many Whitehorse-residents, a stroll along the clay cliffs that overlook the Yukon River, cars coming and going, children walking down the street on their way home from school.
Taking the trail all the way to the end, however, will take you to Hidden Lakes, a sudden and unexpected jewel nestled in the hills in the heart of Whitehorse. These pothole lakes are long, stretching out two fingers fringed by the remains of a 1970s forest fire.
With a pair of resident bald eagles, a plethora of wildflowers, crocuses in spring, followed by yarrow and Jacob’s ladder in the summer, wild roses in the fall, it makes a gorgeous walk any time of year.
It’s also extremely popular with local anglers, many of whom spend afternoons fishing along the water’s edge. The lake is abundant with kokanee salmon and rainbow trout, thanks to Environment Yukon’s stocked lake program, which creates fishing opportunities in 18 lakes across the territory.
Selecting a lake for stocking is a careful process, says Oliver Barker, a fisheries biologist with Environment Yukon. Only pothole lakes — that is, lakes that have an inflow but not an outflow — are eligible, so that introduced fish can’t make it into rivers, where they might become invasive.
The lakes also have to be deep enough that they don’t freeze completely in the winter, because a totally frozen lake means totally frozen fish. The lake is then surveyed for productivity, which is a measure of how many fish it can support based on water temperature, depth elevation and available resources.
If a lake is deemed suitable, the department then carefully considers which type of fish to include, says Barker.
“We try to think about which fish are most suited for which lake,” he says. “And we try to create a bit of variety.”
Stock fish are then “built.” It’s a process of growing fishing fry in tanks at the Whitehorse Fish Hatchery, then transporting them to stock sites via trucks where they are released into the lake. The size of the fish at this point can vary, says Barker. Smaller fish means are more vulnerable to predators, resulting in higher loses, but raising fish larger is more costly and time consuming.
“Our hatchery is very good at building fish…. Compared to mammals, (raising fish) is more like making a batch.”
Previously, the department had been bringing in tiny fish sourced from British Columbia, Barker says, but as of this year, it will be raising fish and releasing them directly from the hatchery.
The fish are usually released in the last week of May or the first week of June, because that’s when the water is closest to the temperature they’re grown in, Barker says, which is best for the fish.
Releasing them into water that is too cold or too warm can shock them, just like when you bring home a goldfish and find it floating belly up because the environment was too different from the pet store.
At Hidden Lakes, the fry release is often a public event, which kids enjoy, says Barker.
“We like to have the kids help.”
Currently, the program stocks mainly rainbow trout and kokanee. Cantalie Lake, accessible only by snow machine, mountain bike or ATV, boasts a population of arctic char which was originally introduced, but is now self-sustaining, says Barker. Those fish haven’t had to be restocked since the 1990s.
Long Lake is also home to a stocked population of bull trout, those green-backed, heavier beauties which are cousins to the smaller and arguably tastier rainbow trout. As many frustrated anglers will tell you, however, there are “fewer and fewer” of them in the lake, and the last time they were restocked there was in 2009, says Barker.
The department is transitioning that lake to be stocked only with kokanees, a favourite with families out for a casual weekend outing, he says.
“Kids especially love kokanee, they’re a very active fish, easy to catch,” he says.
Perhaps most importantly, the program takes pressure off of wild fish species, such as lake trout, which reproduce extremely slowly. A female lake trout can take between nine and 12 years to reach sexual maturity, and only lays eggs once every three years.
Marcella Lake, for example, is stocked with rainbows, which helps take pressure off of the lake trout population in nearby Tarfu Lake. Lake trout fishing in that area is presently limited to catch and release only due to concerns for that population.
“It’s hard to reproduce more slowly than a lake trout,” Barker says with a laugh.
The lakes not only provide fishing opportunities, says Barker, but have important cultural uses as well. People who have never fished before often start with the stocked lakes, and it provides recreation close to home, he says. Many of the stocked lakes are also fishable from the shore, meaning people don’t need to have expensive boats or fancy gear to participate.
“This is a tool that gets at both these mandates,” he said. “It’s an easy way to get into fishing that’s low-cost.”
“There’s increasing interest in making sure we have good stocked lakes and we respond to that.”
Contact Lori Fox at firstname.lastname@example.org