Mystery of dead sturgeon in central B.C. has scientists asking for help

The province is asking for help with a mystery after 11 dead adult white sturgeon were found last week on the Nechako River in central B.C.

The unusually high number has scientists asking people to report and submit photos of dead sturgeon sightings on the Nechako and Upper Fraser Rivers.

Samples of the 11 fish are being tested but provincial scientists say none had visible signs of injury, nor do they believe the fish died because of disease, chemical exposure or fishing activity. 

"It's early days but it's certainly concerning," said Steve McAdam, sturgeon recovery lead with the Ministry of Land, Water and Resource Stewardship.

"At this point we're really at an information gathering stage. The information bulletin went out really to engage the public — they're the ears and eyes on the water. So if people see a fish we want to find it and get it."

The Nechako River flows into the Fraser River near Prince George. Nechako white sturgeon are listed as critically endangered under the Species at Risk Act (SARA). They can live over 100 years, grow up to six metres in length and are considered an iconic animal. 

"The lineage has been around for 250 million years. People call them living dinosaurs ... and I think it's super important to emphasize they're culturally important to First Nations," said McAdam.

WATCH | Couple catches sturgeon at the end of month-long fishing trip in B.C.

How big was the fish?

3 years ago

Duration 0:58

Braeden Rouse felt a tug on his line and after a half-hour struggle landed a sturgeon.

A number of dead white sturgeon have also been observed in the Lower Fraser River this year, but nothing out of the ordinary, according to Sarah Schreier of the Fraser River Sturgeon Conservation Society. The Lower Fraser is the area downstream from Hell's Gate in the Fraser Canyon.

Although not as critical as the Nechako population further north, white sturgeon in the Lower Fraser are considered threatened under the Species at Risk Act with only an estimated 45,000 remaining. 

"Any fish we lose from these abundances — the Nechako population or the Fraser — it's concerning because we want to keep this fish on the right track and get it to recovery," she said. 

White sturgeon have been impacted by a multitude of factors: loss of habitat, decline in food supply like salmon and oolichan, fishing and changing environmental conditions. 

"There's no real smoking gun, to be honest," said Schreier. "It's a hardy, robust fish that survived two ice ages so it is hardwired to survive. But the puzzle is why [these deaths] happen and why isn't recovery happening faster."

People who see and photograph dead sturgeon in the Nechako region are asked to submit the information to Nikolaus Gantner at 250 649-2876, or email nikolaus.gantner@gov.bc.ca.