Flood control endangers fish
March 7, 1997
We could lose half this year’s population of shore spawning Kokanee due to attempts to prevent serious flooding around Okanagan Lake this year says Dr. Peter Dill, biology professor at Okanagan University College.
Already the lake is 2.5 cm lower than it was at this time last year says Brian Symonds, head of the hydrology branch at the environment ministry’s district office.
That draw-down of the lake’s level, to allow the deeper-than-normal snowpack at higher elevations to flow in without overfilling the lake, has already left some of those fragile Kokanee eggs exposed on the shore, says Dill.
It’s particularly problematic this year because the lake is colder than normal for March, so development of the fish has slowed, leaving them even more vulnerable.
However, if the snowmelt begins soon, input from swollen creeks will alleviate the effects of the larger releases of water from the system, he noted.
“If the weather stays cold it could be very serious for the fish,” said Dill.
Ironically, the loss would occur just as scientists such as Dill are learning about the optimum incubation conditions of these shore-spawning Kokanee.
With his students, he will continue to study the shore-spawners as they emerge this year.