July 24, 2008
2008 Kokanee Egg-to-Fry Survival Rate – Best on Record
(WEST KOOTENAY) The numbers are in and the news is good. This year's egg-to-fry survival rate for kokanee at the Hill Creek Spawning Channel is estimated to be 69.4%, making it the best survival rate on record. In 1985 the egg-to-survival rate was 69.2% and for the last two decades, survival rates for kokanee eggs have averaged about 42% so the results for 2008 are exceptional.
"High egg-to-fry survival shows that channel flow controls and annual gravel cleaning have been very well done," says FWCP Steering Committee Co-Chair Wayne Stetski of the Ministry of Environment. In real terms, this means that about 6.96 million fry have emerged from the spawning channel, operated by the Fish & Wildlife Compensation Program (FWCP), and will continue growing and maturing in the Arrow Lakes Reservoir.
In 2006, 36% of the eggs in the spawning channel survived to the fry stage, and in 2007, the survival rate was 51.5%. By comparison, about 15% of the eggs deposited by spawning kokanee in natural streams survive.
This good news comes after lower survival rates in 2004 and 2005 when the egg-to-fry survival rates where 0.8% and 2.8% respectively. Record-breaking rainfalls, an upstream beaver dam, unusually cold weather and compacted gravel may have contributed to the these low survival rates "Since then we've made a number of changes to our operations to reduce the chances of having such low survival rates again," says James Baxter, FWCP senior fisheries biologist. Given the results this spring, the changes seem to be working.
"We will continue to monitor the spawning channel regularly," says Baxter. "An adequate number of kokanee fry in the reservoir is good for the entire ecosystem as well as local anglers."
The Hill Creek Spawning Channel contributes the majority of kokanee production in the upper basin of Arrow Lakes Reservoir. The FWCP, together with the B.C. Ministry of Environment (MOE), also operate the Meadow Creek Spawning Channel at the north end of Kootenay Lake which contributes significantly to the total kokanee production in that system. Egg-to-fry survival at the Meadow Creek Spawning Channel this spring was 53.8% which is an above-average survival rate.
The FWCP works on behalf of its program partners MOE, BC Hydro and Fisheries and Oceans Canada to conserve and enhance local fish and wildlife impacted by the construction of BC Hydro dams. By adding nutrients to the Arrow Lakes Reservoir and Kootenay Lake the FWCP, together with the MOE and others, are compensating for upstream dams that trap nutrients. The spawning channels compensate for streams and natural spawning habitat that was flooded during dam construction.
Fish & Wildlife Compensation Program
103-333 Victoria St. Nelson, BC V1L 4K3 Canada
Tel (250) 352-6874 Fax (250) 352-6178