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This is a question for you koke biologists.
This week we launched at Renegade and in so doing noticed that Indian Creek is sporting dry streambed.
Now the ?.
What happens with the kokes that have been spawning there?
In my mind they don't wander off and find another stream.
Do they go ahead and lake spawn or do they just up and die.
I know some kokes are lake spawners but these have been stream spawners.
After going into spawning mode I can't imagine them returning to pre spawn condition and wait till next year.
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Good question. I sent your question, in an email, to Alan Ward.
In July I caught several cutthroat that were either spewing sperm or eggs and I asked Alan about that. This was his reply.
"Unfortunately, some of those cutthroat will not spawn. We see most of the spawning activity cease by early July. They either simply do not know where to spawn, or more likely this year, they do not have a place to spawn. For instance, Indian Creek is dry, and we typically get more cutthroat spawning there than anywhere. And the Strawberry River was so low that spawning habitat, and access to habitat, was limited. Therefore, we always see some fish that never do release their eggs (and probably more this year), and they end up absorbing them (which is not always healthy for those females)."
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Here is Alan's reply:
"Once a Kokanee goes into spawning mode and turns red, it is dead. There is no going back. Kokanee in Strawberry do not always find a stream to spawn in, and over the years we have observed what appears to be spawning activity in the reservoir. Kokanee have been documented to successfully spawn in lakes and reservoirs elsewhere, and it is fairly apparent that they also attempt this in Strawberry Reservoir as well. We have not initiated any type of study to document the success of stream vs reservoir spawners to date. We looked into it a few years ago through microchemistry, but the chemical signatures among streams and the reservoir were too similar to distinguish among them. However, on average about 45% of our population of kokanee comes from natural reproduction. Some years better, and others worse obviously. I just can't tell you what proportion comes from reservoir spawning as opposed to stream spawning activity. Hope this helps
Alan"
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I've observed kokanee at the mouth of tributaries around the Gorge that they could not ascend. Some of those groups stayed there for the duration of the spawn until they died. Kokanee will definitely pioneer new areas though, and I see that more on years when spawner abundance is high. It's like they want to "get away from the crowds". Sometimes they're in odd locations too, that do not look like quality spawning habitat. In those cases, spawning success is probably low. There's reservoir spawning in the Gorge, and the areas they predominantly use were selected by kokanee (they were not stocked there) and spawning success can be really high. In previous years and studies, the proportion of the fishery from in-reservoir spawning groups was as high as 93%, whereas all the tributary spawning combined was only 7%. Success will obviously vary from year to year due to reservoir elevation, reservoir drawdown in the winter months, and tributary flows, sediment load, and temperature during incubation, etc. Hope it helps, Ryno
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At the time they used genetics from a subsample of fish collected from the reservoir. There's currently a study being finalized that used otolith microchemistry to determine the origin of kokanee in the reservoir, specifically hatchery vs. wild, but should also have the resolution to determine the proportion of tributary vs. reservoir.
