(L-R) Zoe McMillan and Erin Head are second year students at the Recreation, Fish and Wildlife program at Selkirk College in Castlegar. Photo: Submitted

(L-R) Zoe McMillan and Erin Head are second year students at the Recreation, Fish and Wildlife program at Selkirk College in Castlegar. Photo: Submitted

ECOLOGICAL COMMENT: Where have the white sturgeon gone?

A column by Selkirk College Recreation, Fish and Wildlife students

Submitted by Zoe McMillan and Erin Head, Selkirk College students

The mighty white sturgeon is a living dinosaur, existing on earth for more than 200 million years. These colossal creatures can live over a century, growing up to six metres long and weighing up to 1800 pounds. Historically, these gentle giants were abundant in our Columbia watershed, with healthy populations occurring throughout our major rivers. These shark-like fish have survived in the face of catastrophic events, such as volcanic eruptions, ice ages, major floods and mass extinction events. But is their time coming to an end?

In 2018, the B.C. Conservation Data Centre listed the species as critically imperiled provincially (S1 and red-listed) and endangered federally. Habitat alteration in the Columbia basin such as the construction of hydroelectric dams, drainage and diking projects threaten the species, in addition to declining water quality, over-fishing, and human competition for their food sources (salmon and eulachon).

White sturgeon are anadromous (meaning they migrate between freshwater and saltwater), living most of their lives in the Pacific Ocean and returning to spawn in the freshwaters of the Southern Interior. The construction of the Libby Dam (among others) has landlocked certain populations of sturgeon — trapping them between two dams and preventing them from following their natural migration path to the ocean.

Surveys conducted on the landlocked populations in the Columbia River show that nearly every fish in these areas is greater than 30 years old. Since sturgeon don’t reach sexual maturity until 15-30 years of age, this means an entire generation of sturgeon has been lost. This suggests that either the sturgeon are not reproducing, or the young are not making it into adulthood.

Even for the populations who aren’t trapped, hydroelectric dams block access to essential spawning grounds and can even go as far as eliminating them completely. It’s not only the spawners, either — even the immature sturgeon suffer from the dams, as they reduce downstream turbidity and expose them to predators. White sturgeon cannot sustain their numbers anywhere in the Columbia River system, making the long-term outlook extremely dire.

RELATED: Sturgeon habitat restoration resumes at Arrow Lakes Generating Station

The Canadian government has initiated a recovery plan for the white sturgeon, including maintaining and restoring natural habitats and breeding grounds, as well as monitoring their populations and taking on necessary research projects. Since the recovery plan was revised in 2013, the Spokane and Colville Tribes monitor the survival rates of sturgeon in the upper Columbia River routinely.

“They are quite a charismatic species and it’s a fish that has been around for millions of years. So, you don’t take it lightly when it’s in danger,” biologist Steve McAdam said.

What can we do? Locally, citizens can do their part to ensure water quality does not decline further, support existing pollution control measures and the current ban on sturgeon harvesting, join a clean-up program and report any habitat deterioration they may see.

Due to their long generation time and numerous threats they face, the white sturgeon may be at risk for a long time, but hope is not lost. With the support of the community, the government, and Indigenous groups, it is possible to bring back our mighty white sturgeons.

Zoe McMillan and Erin Head are second year students at the Recreation, Fish and Wildlife program at Selkirk College in Castlegar.



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You can read about a sturgeon habitat restoration project on page 14.

Sturgeon