There is this absolutely fantastic fly fishing episodic period every season here on the upper Yakima that too many anglers just don’t know about. I’ve been selfishly indulging myself in it every single season for almost 12 years now. The Golden Stonefly Hatch of the Yakima River.
I’ve been in the upper, save for last evening big bust of a float in the LC, and the fish in the upper Yak have begun their annual key in to these big delicious golden treats. Every season sometime in June and the first few weeks of July, we get our Golden Stonefly Hatch. A large yellow and gold Stonefly species that is much like the Salmonfly. The females are typically 2-3 inches with males a little smaller. They hatch nocturnally or early in the morning, by climbing up onto rocks, the bank, and debris and popping out of their shuck. The change from nymph to adult can take a few minutes to hours depending on conditions. They’ve been in the nymph stage for a few years at this point. Once they hatch they retreat to the trees and brush to find a mate and get down to business.
Once they’ve completed their funky fun time dance, the males die off, and 5 females hang out and develop an egg sac. Then as the heat of the day comes on, right now around 2-3 pm the females migrate back to the river by flying down to the surface and depositing eggs back into the river for the next generation of trout food. The eggs, dense little grains of sand sized waiting Stonefly larva, work their way down into the substrate of the rove bottom where they will reside for the next few years feeding and growing. The annual stonefly migration refers to the time when the nymphs come out of the substrate, get their last bit of feeding in by veraciously eating everything in sight before finally pushing to the surface to hatch.
I gauge this migration timeframe by seining the river at various depths and looking to see how many golden nymphs show up. When they are in the knee deep water in great numbers it means shits about to go down. We had that last week and things are starting to go down this week.
Even though there are not a vast number of them on the river surface these fish know they are hatching and they act appropriately. Especially cutties. Fish will seek out, chase down, gobble up, skyrocket for, and absolutely smash the crap out of them. And there’s a reason why. A Golden is a big meal. Could feed a fish for a day kinda meal. So when they decide to eat it… they EAT it. That big bug can fly, it is super fast on the river swimming, it’s big and crunchy with a hard shell and spiked legs…it takes work to eat it. So fish like to make sure they get it in the first try…so they smack it hoard!!!
That time is upon us. Fish in the upper are keyed in on the Golden’s and are starting to regularly smack them. Which is awesome. Earlier than last year but with the way this spring and early summer has went, I’ll take what the river gives me and I’ll roll with it.
Come get in on some sweet big dry action before it’s over.