>>1089751I supervise a kokanee project right now, the organisms are just starting to stage in this area, we go out and seine them up on a boat and then floy tag all of them to do mark/recapture spawning estimations on them in the tributaries.
A strangely variable organism, they go through wild population fluctuations out here and there's not a strong correlation between spawning years as calculated via sibling regression analysis. With a multitude of salmonids, even sockeye (still o. nerka but a sea run version obviously) you can do sibling regression analysis to get an estimation of next years 3 year olds by enumerating this years 2 year olds and then extrapolating that information via historical percent contributions to spawning run relative to age. In most places there is a fairly stable age composition of spawners with a dominant year class. Kokanee still prove difficult to predict though.
We've tried to use SARs too (Smolt to adult returns) in order to calculate the estimated adult return run sizes via enumerating kok smolts via peterson mark/recapture and then comparing that to historical analysis of smolt outmigration numbers and then the adult return size 3 years later (the dominant age at spawning) and still no strong correlation.
Just a pretty strange fish that's hard to predict. We just do same year spawning run prediction to help set fisheries via hydroacoustic analyses, you can pretty well enumerate what's out there at that current time via that methodology.
