Thursday, May 30, 2013


(jgmiller@---- Gray  Drake spinner)
(spinner flight yesterday morning..msupinski@)
Siphlonurus mayflies hatch from May thru late July in Michigan-with some of the biggest hatches in the country occurring on the Muskegon and Pere Marquette- they also hatch out west on spring creeks and eastern tailwaters.They just started in earnest yesterday on the Muskegon and have been hatching for a week on the PM. They are a perfectly formed and a true looking mayfly that has a very complex lifestyle with its three species:rapidus,alternatus and quebencensis-rapidus are the largest and the ones hatching now- a true size 10-12.
Though the eggs are laid in the riffles by the spinners, the nymphs mature there and start migrating towards shore as early as February. They are very fast swimming nymphs-like minnows- and crawl up on vegetation strands, trees,rocks and any backwater/slough area bank structure to hatch- rarely do trout see the nymphs since they are crawlers. Once they hatch in the woods/banks and are drwan to lights by the dwellings, they molt and come back as spinners- again!- almost never do  trout see the adult duns!Emergence takes place when water temps are 55 to 66 F.

( ridiculous mating swarm at 6:00pm in 2009)

It is a very frustrating and complicated hatch since their are nights where their are so many spinners and the water turns to sawdust that the fishing is impossible. Then there are the countless nights where spinners appear and then vanish because it gets cold or there are too many of one gender and not a good equal mix of both male and female for copulating- thus no mating. Also they are drawn to heat of boats and anglers standing in them -thus always a swarm above your head.Often on very cold or very warm days- the extremes are not to the liking of drakes- the spinner flights occur in the morning-vs. the more traditional evening. The ideal conditions are an overcast warm situation with lots of moisture in the air-humidity is to their liking.
( notice the curved body shape of the spinner and the body banding so important for selective/reflective fish)
Michigan trout taking drakes can become ultra selective/reflective when the hatch is on for weeks. The first few nights brings a feeding frenzy-quickly subdued once the fish get satiated. Then they feed for short intervals often targeting clusters- two males hooked up with one female in the mating act that fall to the water surface and the males brake up and fly away. Or the fish will target slender , curved, burnt-up spinners only. Position yourself in a long flat below the riffles for consistent action that will last for longer periods of time. If the spinner fall doesn't happen at night- sure bet it will in the morning between 8 and 11 depending on air temps.Also, there can be great spinner flights just before thunderstorms since the change to dark and moist conditions, coupled with cooler air signals night and the bugs are duped into spinner mating. Note: that on years like this one when we have record rainfall, cool air and the water levels are high, the gray drakes are all over. Last year';s drought and heat wave saw almost no drakes since they dried up along the shorelines or burnt up because of the heat- when the mosquitoes are like elephants like this year- its drake time!- besides; their bodies have similar banding's and look alike except for the mayfly wings!
Also , sulpher and caddis hatches precede the drake spinner fall and the fish will focus on them...but once the drake appears, the selectivity bi-polar switch will occur and the fish will target every last scrumptious spinner. If the mating spinner fall doesn't materialize like it should, the trout will switch back to the caddis/sulpers immediately since chow time is of the essence.
Enjoy!- but be prepared to pay your dues with this finicky hatch!