What conditions make for a good spinnerfall?

Acristickid

Acristickid

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Suppose the bugs are wired for certain conditions and vary for stream to stream.

Spinnerfalls seem to be kinda of elusive to me. One day I hit it and the next day with similar conditions it was a dud.

Any concensus on this?

For example: olives, would it be several rainy days for the hatching followed by several calm windyless evenings?

Another time on broadwaters on Penn's a swarm of March Brown spinners gathered over the riffled water but just as darkness neared the wind kicked up and put them off.

I really saw a great sulpher spinnerfall about 5 years ago and have not experienced any of that magnitude since. Humm.
 
I am sure it is species dependent, but I tend to look for windless, cloudy days.
 
Well, I think it is species dependent. A downpour between the hatch and the spinner fall can put a hamper on things. Depending on species, that time period can be as short as a few hours, or as long as a week. I'm sure there's critical times within those periods.

For the actual day of, wind is bad. A cool, cloudy day extends the spinner fall, i.e. its not as strong but lasts a long time, which can be better for fishing assuming its still strong enough to get em to rise. A hot sunny day will result in a very heavy spinner fall in a very condensed time frame. This can lead to frantic action, but in some species it occurs after dark, which makes things tough, and sometimes the flies are so dense fishing becomes tough as well.

Also, any water conditions which affect the density of the actual hatch, may also later effect the density of the spinners.

Trico's were always easiest for me to predict. A morning spinner fall. Wet and it'll happen late and sparse, maybe spread out over the late morning and even early afternoon, perhaps only with occasional risers. Cloudy and it'll happen late, maybe 9-10 a.m. Sunny, and it happens early, perhaps as early as 7 a.m. The fun days are the sunny days with fog in the valleys. The moment the sun burns starts burning through the fog, they'll hit the water in ridiculous numbers. Usually 8-9 a.m.

For most evening spinner falls, I want a 2-3 day period with no rain, followed by a dry but cloudy evening with no wind to give me my best fishing. Sun is good if you want the wow factor, but the good fishing will be really condensed into that half hour or so after the sun sets but before the bats fly.

March Browns, especially, seem to team up on me. Several days of hatching with no spinner falls. Then one evening the flies from several days all fly at once. Quite an amazing sight when you catch it, but maddening to try to time it right.
 
pcray1231 wrote:
Well, I think it is species dependent. A downpour between the hatch and the spinner fall can put a hamper on things. Depending on species, that time period can be as short as a few hours, or as long as a week. I'm sure there's critical times within those periods.

For the actual day of, wind is bad. A cool, cloudy day extends the spinner fall, i.e. its not as strong but lasts a long time, which can be better for fishing assuming its still strong enough to get em to rise. A hot sunny day will result in a very heavy spinner fall in a very condensed time frame. This can lead to frantic action, but in some species it occurs after dark, which makes things tough, and sometimes the flies are so dense fishing becomes tough as well.

Also, any water conditions which affect the density of the actual hatch, may also later effect the density of the spinners.

Trico's were always easiest for me to predict. A morning spinner fall. Wet and it'll happen late and sparse, maybe spread out over the late morning and even early afternoon, perhaps only with occasional risers. Cloudy and it'll happen late, maybe 9-10 a.m. Sunny, and it happens early, perhaps as early as 7 a.m. The fun days are the sunny days with fog in the valleys. The moment the sun burns starts burning through the fog, they'll hit the water in ridiculous numbers. Usually 8-9 a.m.

For most evening spinner falls, I want a 2-3 day period with no rain, followed by a dry but cloudy evening with no wind to give me my best fishing. Sun is good if you want the wow factor, but the good fishing will be really condensed into that half hour or so after the sun sets but before the bats fly.

March Browns, especially, seem to team up on me. Several days of hatching with no spinner falls. Then one evening the flies from several days all fly at once. Quite an amazing sight when you catch it, but maddening to try to time it right.
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I've seen this time after time, especially on Penns (during the last few Jams too). The MB spinners begin hovering at tree-top level in the evening, but never come down, they just disappear. Any theories?
 
Last year for the MB spinners at the JAM it rained 3 TIMES! for about 10 minutes right at dusk. The spinners came off the trees, started to descend and then it rained... 3 TIMES! They never hit the water. I was so ticked!

I think you just need consistency. If you have the same weather conditions for a few days in a row it shouldn't damper the spinnerfall. Barring a downpour the insects will do whatever it takes to reproduce.
 
I've also seen coffin flies swarming around like crazy in the eveinings, and you'd think they were gonna fall heavy. Only to go back up in the trees at dusk. I'm guessing that they just weren't ready to do their thing yet

The best conditions are warm, calm eveings IMO.
I've never seen a heavy spinner fall on cold, windy, or rainy days.
Although I have seen spinners on the water that were likely blown, or washed in.
But they don't seem to swarm over the riffles much in those conditions.

The spinners come down earlier in april - have often seen them around 5-6 pm.
But in warmer conditions in may, they usually wait until dusk.

Occassionally you'll find fish sipping spinners in the early morning - besides tricos. These are stragglers from the night before
 
2 springs back on Oil I hit a big spinner fall just after a heavy rain. It was one of those heavy pop up thunderstorms, where its just a ridiculous downpour for 15 minutes, then gone and the sun comes back out.

Fish had just started to rise when the rain hit, in fact, I had a nice 15" brown on and got wet because of it, couldn't get out the raincoat quickly cause I had my hands full, it was that sudden, like someone threw a switch, then threw it back off. But the rain put the fish down. We decided to move a quarter mile or so. Along the wet bike trail, there were march browns trying to lay eggs everywhere! It was darker there due to the trees, and the wet blacktop apparantly looked like water and fooled em. Thought right then that it was gonna be a special night, and it was. When dusk made it out of the woods and to the stream, all heck broke loose...

But I think a decent % of MB's may fall dead on land some evenings. Many mayflies fall exhausted on the water and then the eggs fall off while they float. But MB's make repeated runs at the water to lay the eggs and then take back to the sky (you can see em do this), or else drop them from the air. Next time your under em, check your hat, I've found mine covered in a pollen like substance I believed to be mayfly eggs! But anyway, since they don't die immediately, they end up falling wherever, which isn't always on the water.
 
Just to put 2 cents in , the conditions of the hatch preceding would be the best indicator of what the spinnerfall should be like. If there is a heavy hatch there will be a heavy spinnerfall , has to happen sometime subsequently. I agree on it being species specific. So , if there is a heavy hatch , wait for the conditions that favor a spinnerfall of that mayfly. I think those conditions vary greatly but that's another subject and could be a lengthy one so i'll leave it at that.
 
Number one factor for a good spinnerfall is wind. I think many of the species want to drop their eggs in a particular type of water (head of pool, tail of pool or riffle). When the wind is blowing, it prevents them from gathering at those particular locations in big numbers. I may have only fly fished a short time but fished in some way 5-7 times a week from last April through June. Got to see and learn a bunch.

I've seen killer hatches with no spinners. To argue Osprey's point, a big hatch followed by a big spinner fall would be true if the bugs hatched and then came right back to mate. I think most spend 1-14 days in the trees prior to mating. You could walk up on a pool and see zero hatching insects but there was a large dun emergence for the last 7 days. Odds are that you will see a spinner fall. Luck, homework and time on the water gets you stumbling into big spinner falls.

I haven't noticed much difference between cloudy vs. sunny days. The sunny days may cause the bugs to come down later than on a cloudy day. Rain and cold seem to have an impact on the number of returning bugs. If you get a very cool evening or some light rain, the number of returning spinners is usually less than if it's calm and clear. I'm no expert but that's what I've found so far in my fishing.
 
Rod..........If there is a Hatch , there has to be a subsequent Spinnerfall , sometime. It might occur over several days but it HAS to occur or there wouldn't be any mayflies. You know about the life cycle of a mayfly right? So if there is a hatch , then , they mate , and then , fall. HAS to happen.
 
Osprey agree. I have had this conversation plenty of nights after seeing the spinners way high up and then never see them hit the water. I think they get back to the water to lay their eggs at some point. I think wind, rain, temperature and timing have a lot to do with as discussed.

The dun leaves the water, they eventually and at some point the spinners make their way back to lay their eggs in the water.

I have been up at First Fork for several days in a row when the MB spinners have not landed on the water in the evening. Very frustrating. They have to be getting back on the water sometime in the middle of the night is the only thing I can see.

I have even stayed out just past dark and night fished with big rusty brown spinners to see if this holds true. I have had mixed results. Usually not staying out much later than 9:30 to do so.

Often I have speculated that a good water and air thermal difference can help too during a spinner fall. Warmer water and that same warmer air can ride over a stream. When colder evening air moves in it creates a micro temperature inversion. Spinners then bounce off the water rise up, hit the cold air and bounce down more quickly.

Not saying this creates a spinner fall just effects their behavior during one. Would prefer these conditions over a windy night any time.
 
It might occur over several days but it HAS to occur or there wouldn't be any mayflies.
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1. We're trying to predict a spinner fall for a given day. There are certainly things that happen that delay it. For instance, bugs may have hatched over the last several days in huge numbers, and be slated to fall this evening. But with current weather conditions, they'll all wait till tomorrow. If tomorrow's weather sucks too, they'll wait another day. Yes, they will eventually do their thing. But past hatch performance isn't a great predictor of the intensity of a spinner fall in a given day.

2. There are failures. Huge hatch, spinner fall comes, big wind blows up, and all the bugs are blown off course and fail. Maybe they are killed before mating. Maybe they end up laying in a mud puddle. In any case, nature isn't a perfect science, there will be events which destroy an entire hatch period before they can reproduce. This is why mayflies hatches and spinner falls occur on multiple days instead of just one. Think about it, their strategy is huge numbers so that predators can't have a great effect. The ultimate of that stategy would be if every one hatches on the same day, and mates on the same day. That doesn't happen because its too dangerous, one thunderstorm could ruin the whole thing.

I've even seen occurances of failed spinner flights used to predict the strength and/or timing of next years hatches. I think it'd be very hard to predict, but I don't doubt there's something to it.
 
These things are moot to many anglers- because you go fishing when you have time and not really based on conditions. But it always helps to improve your chances. Not being a local to "good" water I am well aware of this chase.

Happy Monday.
 
because you go fishing when you have time and not really based on conditions.
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Yes, you fish when you have time, but you fish WHERE you expect the conditions to be ripe.

1. Late spring/summer thunderstorms hit one spot and not another 10 miles away.

2. Some streams fish respond well to hatches/spinners, others the bug life is poor or the fish don't respond. Expect a good hatch/spinner fall, go to the dry fly stream. Expect poor bug conditions, go to a nymphing stream or a brookie stream.
 
Don't get me wrong here folks , there might be a huge hatch of duns for days and the spinners/adults may come back slowly and according to weather conditions or the moon phase or whatever , the point i was trying to make was that if they didn't come back at all that would be the end of that. I know the original question was "what conditions make for a good spinnerfall?" my answer would still be the same , a good hatch of duns. I agree the wind and rain and sun put them off , might make them return sporadically or in smaller amounts than the dun hatch but those bugs are hard wired to know when to do their thing , and i mean from the start to the finish. For example , for a few days leading up to a hatch , the nymphs might start to get a little more active , I've even read they make sub-surface migrations , pick up and float to another spot en mass without hatching out , next the duns come , sometimes that is sporadic too , sometimes not , but once they make that move they are on a mission that has to end in a fall eventually. I hope yinz can make sense outta that.
 
I do make sense out of it, and agree to a given point. I just think it is a poor predictor of spinner fall for a given evening.

Several days worth of poor hatches falling all at once will still outnumber 1 day's worth of a strong hatch.

If a hatch has 10 days of spinner falls, only 1 or 2 need to be especially successful to ensure the next generation. I think you overestimate their success rate. Well more than half of the bugs may fail at their 1 mission, and that number can vary greatly year to year.

Like many other species, the mayfly's evolutionary strategy is overkill. i.e. a huge number of bugs in a short time period, each capable of producing a huge number of offspring, but a relatively pitiful individual success rate.
 
YEP!!! That's what i mean when i say there may be a huge hatch of duns for several days and then , the adults coming back to mate may be sporadic but enough to ensure that some eggs make it. The reverse is possible too , in fact i've seen it , the Cahill hatch is often slow/sporadic over several days and then there's a huge spinnerfall. Have you ever noticed that different species of spinners do a different "mating dance" than others? Some do the up and down dance and some do the back and forth. LOL figure that one out.
 
Ok, I'm getting confused.

The original question: What conditions favor a strong spinner fall? Presumably the purpose is to increase one's chances of timing it right.

You hold that a good hatch of duns makes a good spinner fall, but then also agree that local weather conditions can have a great effect on the strength, timing, duration, etc. of the spinner fall.

I don't think that gets anyone any closer to a usable truth. What we want to know is which weather conditions cause what?

FWIW, the one thing we are all agreeing on is wind. Wind is a bad sign for your chance of getting a good spinner fall that day.
 
I'm not an entomologist.......but i did stay at a Holiday in once. Wind would be a good thing to avoid if looking for a spinnerfall , i agree with that 100%. How about humidity? Personally i think bugs like high humidity , but not rain , so high humidity without rain.....????
 
How about a partly cloudy , windless day where it seems like it's gonna rain all day but doesn't?
 
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