This year marks the tenth year that the Upper Columbia White Sturgeon Recovery Initiative (UCWSRI) will be releasing hatchery-raised juvenile sturgeon (from wild-stock adults) into the Columbia River. The public event runs between 2 and 4 p.m., Monday April 18th, at Hugh L. Keenleyside Dam, near Castlegar.
Over the last decade these release events have become very popular among both elementary school children and the public. That’s not the only good news: with many years of data under their belts, biologists know that the survival rates for those fish released are relatively high.
“On average, of all the fish released into the river in the spring, we estimate that approximately one quarter survive the first six months,” says white sturgeon coordinator James Crossman with BC Hydro. “Juvenile sturgeon that survive are growing fast and making use of habitat throughout both the Canadian and US sides of the border.”
Those survival rates go up dramatically once the fish have managed to surpass the six-month mark. During the next year the survival rate jumps to about 80 per cent and then 90 per cent the subsequent year.
Although the survival rate is healthy, the upper Columbia River adult sturgeon population is anything but. There are estimated to be around 1,000 adults between Hugh Keenleyside dam and the US border. What’s more, the population has been virtually unable to reproduce in the river for more than 30 years. This is why this juvenile aquaculture program is so essential.
“During our sampling we have found the odd juvenile from natural reproduction in the river, but in essence there is no successful natural recruitment occurring,” added Crossman. “And we have a long wait to see if our hatchery-raised juveniles successfully reproduce one day – typically a female sturgeon will not reach reproductive maturity until 25 years of age.”
The success of the sturgeon aquaculture program is also showing no detrimental impacts on other native species such as rainbow trout.
“From aerial counts of rainbow spawners and redds - their gravel “nests” - we have seen a consistently upward trend in numbers in the lower Columbia River from 2000 to 2010,” says Gerry Nellestijn, chair of the UCWSRI Community Working Group. In the last decade we have observed main stem counts for both going from about 500 to 2,000 – a four fold increase. In short, the fishing has just got better and better in this stretch of river these last few years.”
Approximately 4,000 ten-month old white sturgeon juveniles will be released into the lower Columbia River.
The sturgeon release event for the public is supported by the Fish & Wildlife Compensation Program (FWCP), BC Hydro, Freshwater Fisheries Society of B.C., Teck, Golder Associates, Poisson Consulting, and Zellstoff Celgar Ltd.
The event is free and registration is not required. For more information contact the FWCP at 250-352-6874 or visit fwcp.ca . For more information about the Upper Columbia White Sturgeon Recovery Initiative visit uppercolumbiasturgeon.org.