Matching Fly Size to Nymph Size?

ts47

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I'm trying to get my fly boxes better organized. I've been through hatch charts and memory to create a written list of what fly patterns and what sizes I need to keep in my boxes for my waters. So here's my question, and I hope it's not too dumb...

If the hatch is for a size 14-16 dry fly, how can I determine the size of the matching larvae, nymph, or emerger I should have in my box?
 

LePetomane

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I am not a believer in the big, "buggy" nymphs. I like them small and streamlined. That is how the bugs in the water look. I use the same size as the dry.
 

silver creek

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I'm trying to get my fly boxes better organized. I've been through hatch charts and memory to create a written list of what fly patterns and what sizes I need to keep in my boxes for my waters. So here's my question, and I hope it's not too dumb...

If the hatch is for a size 14-16 dry fly, how can I determine the size of the matching larvae, nymph, or emerger I should have in my box?

Not a dumb question at all. I wondered the same thing early on.

Rule of thumb is that the nymph is about the same size as the adult.

Even if it is slightly larger or smaller, the same sized nymph (for example, a size 14 nymph for a size 14 adult) will match it better than a larger size 12 or smaller size 16. The same goes for emergers.

Follow this rule of thumb: For sizing: Nymph = emerger = adult = spinner

So it is easy. For sizing: Nymph = emerger = adult = spinner

One caution on small flies and especially patterns tied on "big eye" hooks is that fish include the hook eye as being part of the insect.

Although we fisher consider a size 18 hook to imitate an insect with the body length of a size 18 hook, the fish interprets the size 18 as a larger size 16 insect. So with small patterns, go one size smaller since the hook eye makes the pattern one size larger. For a size 12 fly the length of the hook eye makes no difference but for a size 18 it does.

http://www.garyborger.com/2012/10/08/all-hooks-are-not-created-equal/

“Many anglers had noted over the years that if the fish doesn’t take the fly that seems to be the right size, then try one a size smaller. However, what I had not understood, and what everyone else had not understood it seems, is that the eye is a very important component of the overall imitation, especially in smaller sizes. Because of the hook eye, a fly dressed on a size 18 looks the same size as a natural that measures a size 16. So, I no longer measure the hook in the traditional manner, from back of the eye to bend. I now measure them from the front of the eye to the bend.
 

ts47

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Not a dumb question at all. I wondered the same thing early on.

Rule of thumb is that the nymph is about the same size as the adult.

Even if it is slightly larger or smaller, the same sized nymph (for example, a size 14 nymph for a size 14 adult) will match it better than a larger size 12 or smaller size 16. The same goes for emergers.

Follow this rule of thumb: For sizing: Nymph = emerger = adult = spinner

So it is easy. For sizing: Nymph = emerger = adult = spinner

One caution on small flies and especially patterns tied on "big eye" hooks is that fish include the hook eye as being part of the insect.

Although we fisher consider a size 18 hook to imitate an insect with the body length of a size 18 hook, the fish interprets the size 18 as a larger size 16 insect. So with small patterns, go one size smaller since the hook eye makes the pattern one size larger. For a size 12 fly the length of the hook eye makes no difference but for a size 18 it does.

http://www.garyborger.com/2012/10/08/all-hooks-are-not-created-equal/

“Many anglers had noted over the years that if the fish doesn’t take the fly that seems to be the right size, then try one a size smaller. However, what I had not understood, and what everyone else had not understood it seems, is that the eye is a very important component of the overall imitation, especially in smaller sizes. Because of the hook eye, a fly dressed on a size 18 looks the same size as a natural that measures a size 16. So, I no longer measure the hook in the traditional manner, from back of the eye to bend. I now measure them from the front of the eye to the bend.
Thank you Silver!

This is very helpful and answers my question. I added your rule to my list of flies.
 

silver creek

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Rather than estimate the size of the naturals, I use a sampling net to catch the naturals which are floating by or flying in the air. It is like a small butterfly net. I can extend to catch flying insects out of the air. I can extend under water to the river bottom to collect samples, or collect sample right at the surface.

I have posted on how to build the net before BUT it seems the link I tried to my actual post no longer goes directly to my post. It goes to the the start of the original thread. So here is how to build a telescoping seine/sampling net that will fit into your vest pocket:

You need an aquarium net, 2-part epoxy, and a telescoping handle. You can get one at Harbor Freight which has a magnet on the end for picking up lost metal objects. OR you can use an expanding antenna from an old broken transistor radio or a telescoping pointer.









1. Bend the net hand back over the front of the net. The handle in the photo would then be folded back over the opening in the photo above and pointing to the left side rather than to the right side. This seems strange but I will explain why later.

2. Take the end off of the retractable magnet. Put it next to the net handle. Measure how long the net and the telescoping handle can be for the net to fit easily into one of your large vest pockets even with a fly box in the same pocket.

Now you know why you folded the handle back - so the telescoping handle is bent over the net so it can fit into a vest pocket.

If the net is too wide to fit into your vest pocket, you will need to cut off the frame and make a smaller frame out of coat hanger wire and put the net on it. That is what I had to do.

3. Cut the end of the net wire handle and take the plastic coating off of the one of the frame wires of the net. Now try to figure out how many sections of the telescoping handle you have the remove so that the wire will fit into the hollow end section. If you make your own frame out of coat hanger wire, use the coat hanger wire to figure out how many hollow sections of handle your will need to remove.

You can tell by the photo that the second or third section is large enough for the net wire frame to slip into it.

4. From the measurement you made in instruction (2), cut back the net handle so it it is 2 inches longer. Shorten one of the plastic coated wires by 2 inches. Remove 2 inches of the plastic from the other net handle wire, straighten the wire, and put it into the handle.

Check to see if the net will fit into the vest with a fly box in the same pocket. Adjust the handle length as needed.

If you are sure everything is right, then epoxy the the cut end of the handle wire to make it smooth. Pull out only about 1 inch of the wire from the hollow end of the tube, coat it with epoxy, and insert it back into the hollow tube of the retractable handle. Remove the excess epoxy.

Be careful with the epoxy. DO NOT USE TOO MUCH EPOXY or some of it will come out of the bottom of the hollow tube and it will glue the handle tubes together.

Now you have a telescoping sampling net that can be used to catch flying insects as well as floating ones. I find it especially useful to sample things floating below the surface film and also to sample insects living in weed beds or aquatic vegetation. With net downstream of the vegetation, shake or kick the underwater vegetation with your foot and insects will be captured by the net. I have found scuds, aquatic worms, pupa that you would not know were present if you did the traditional turn-over-the rock-and-look ploy. Not all fish food crawls around on the stream bottom. In Wisconsin it is also useful for sifting through the muck for Hexagenia nymphs and other burrowing nymphs.

I also carry a nylon 5 gallon paint bucket nylon strainer bag. Buy it at Lowes or Home Depot.

Put it over your landing net for a DIY Quick Seine.





 

old timer

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I try to make my best guess on what the trout are feeding on but it's always just a guess. I do my best to catch a fish and then pump it's stomach. Only then can I be sure what the fish are feeding on and I can match it. It can be pretty surprising sometimes what we find in the stomach. It's almost always a variety of bugs and sizes.

Over the years I found it more important to work on presentation than trying to figure out the perfect fly to use.
 

KenBrown

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I try to make my best guess on what the trout are feeding on but it's always just a guess. I do my best to catch a fish and then pump it's stomach. Only then can I be sure what the fish are feeding on and I can match it. It can be pretty surprising sometimes what we find in the stomach. It's almost always a variety of bugs and sizes.

Over the years I found it more important to work on presentation than trying to figure out the perfect fly to use.
I am quickly learning the same thing. The other night a sulphur hatch was going off at the stream. I had a size 14 black dry fly while the sulphurs where whitish about a 16-18. A rainbow slurped it off the top right at the top of a sandbar. Many previous casts in that same area with nothing.
 

ts47

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Looking at Silver's post above, I have the same Home Depot paint strainer/seine that fits over my landing net. I also built a seine out of two broomsticks and an apx. 4' x 4' piece of window screen. I wrapped duct tape on the edges of the screen material just to give the edges more strength - in case anyone decides to build something similar. I have taken to looking at the hatch charts and using my seine to sample the bugs in the water before attempting to fish. This has helped with some of my bug selection and will continue to do so as I spend more time on the water.

My current challenge is that I've never taken the time to write down a list of what bugs and what sizes should be in my fly boxes/I need for my waters. Sitting in my office, I'm using hatch charts and memory as a start. Now that I have an actual list started, I will grow it by watching what I see on the water and sampling bugs with a seine.

EDIT: I'm pretty sure that another of Silver's posts some years back is what got me started on seines and bug sampling.
 
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silver creek

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I try to make my best guess on what the trout are feeding on but it's always just a guess. I do my best to catch a fish and then pump it's stomach. Only then can I be sure what the fish are feeding on and I can match it. It can be pretty surprising sometimes what we find in the stomach. It's almost always a variety of bugs and sizes.

Over the years I found it more important to work on presentation than trying to figure out the perfect fly to use.
I am quickly learning the same thing. The other night a sulphur hatch was going off at the stream. I had a size 14 black dry fly while the sulphurs where whitish about a 16-18. A rainbow slurped it off the top right at the top of a sandbar. Many previous casts in that same area with nothing.
I am not following the logic of presentation being the difference in this case when "Many previous casts in that same area with nothing."

If the logic of presentation trumping the fly is correct, it follows that all the previous casts were ineffective because ALL had poor presentation! I seriously doubt that is true. So the odds are that in this case, the fly had something to do with the success of that cast.

Here's what Gary Borger said when I asked him about "presentation" vs the "fly" conundrum.

It is ALL presentation. In other words, the "presentation" vs the "fly" conundrum is an artificial construct.

Gary argues that everything, from the clothing we wear, the way we wade, the place we stand, the cast we make, the mends we perform, the fly we choose, etc, etc...... it is ALL PRESENTATION. In fact, even the knowledge we have influences our "presentation."

This argument of presentation vs imitation probably started the moment the first angler showed his buddies how his artificial fly fooled the first fish ever caught on a fly.

Here is a somewhat tongue in cheek article the delves into this never ending saga of presentation vs imitation

http://www.sexyloops.com/carlos/age-old1.shtml
 

KenBrown

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What I meant was that my presentation was not good. I either 'flopped' the cast or it wasn't quite where the fish was. I referenced the black fly because the hatch was actually white flies..thusly my point is that when the fish took the fly, it was because of the presentation and not the color/size of the fly

From my newbie point of view, this will always be a reoccurring topic in terms of fly fishing.
 

dennyk

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One of the fun things I enjoy doing is turning over some stream bed rocks, and tree branches and collecting some bug samples. I carry a small container with me to keep them in until I get home where I try to replicate the size and coloration. This stuff is just fun!

Good Luck Todd!

Denny
 

ts47

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To the presentation vs. imitation argument, I have been in waters where I get bump after bump of my fly with little catching going on. Then realizing that I have improperly matched the fly the fish are keyed in on, switched that fly to "match the hatch" so to speak, and had hookup after hookup.

I believe as has been stated in posts above that presentation trumps fly selection "always". I also believe that fly selection is a part of it. In my example above, presentation was not the problem, fly selection was. The answer all too often is... "It depends".

To take things a step further, part of the reason I'm putting together a list of flies and fly sizes is to reduce the number of patterns in my boxes. As an example: A parachute adams mimics a great number of hatches. Where it does in basic color and shape, I do not plan to carry other patterns. Where it doesn't, as in a sulphur hatch where the bug is a much lighter color, that would be another pattern I would carry. I'm trying not to "overthink things" but rather get "better organized", and in doing so simplify my boxes. Time will tell if I have any idea what I'm doing or not.
 
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ts47

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One of the fun things I enjoy doing is turning over some stream bed rocks, and tree branches and collecting some bug samples. I carry a small container with me to keep them in until I get home where I try to replicate the size and coloration. This stuff is just fun!

Good Luck Todd!

Denny
Me too... I should have added that to my post talking about bug sampling.
 

ts47

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I am quickly learning the same thing. The other night a sulphur hatch was going off at the stream. I had a size 14 black dry fly while the sulphurs where whitish about a 16-18. A rainbow slurped it off the top right at the top of a sandbar. Many previous casts in that same area with nothing.
Here is the question that can't be answered... With everything else being equal, would you have caught more fish if you had a white size 16 fly instead of a black size 14 fly? Fish do have some sense of color - assuming the fish were actually feeding on the sulphurs. Your fish could have been one that was feeding opportunistically rather than keyed in on a particular bug. THIS is where my, "It depends" comment comes from. If there is a hatch going on/the fish seemed keyed in on a particular bug - matching the size and general shape is what I do first. Then, if I can, I try to match the color. Sure. Presentation matters most. Bug selections matters too.

If fish are feeding opportunistically, the above statements are out the window.
 
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old timer

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Of course, the fly has to be considered. If I fished a hopper in the middle of winter, no matter how ell I presented it I wouldn't have any success. On the other hand. If I presented the perfect fly for the conditions poorly I wouldn't have much luck either. The fly is important but maybe not as important in most situations as some think. Sometimes trout are very picky and need close to the right fly. However, I think some get carried away with imitation. Will the wrong shade of olive keep you from catching the fish if you presented it well? I have my doubts.

I'm a big fan of the North Country Spiders. They aren't an imitation of anything but have worked for hundreds of years. I've gotten them to work when nothing else is working. Even during an obvious hatch. How is that explained? I believe it's because the fly shows life with the soft hackle. It looks like something to eat to the fish, so they do. How are attractor flies explained? They don't match anything. Have you ever got a Royal Wulff to work during a BWO hatch or a Caddis hatch? I have.

Until we can get a trout to talk. We don't know what they're thinking when they take or don't take a fly. Meanwhile we use what works.
 

ts47

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Of course, the fly has to be considered. If I fished a hopper in the middle of winter, no matter how ell I presented it I wouldn't have any success. On the other hand. If I presented the perfect fly for the conditions poorly I wouldn't have much luck either. The fly is important but maybe not as important in most situations as some think. Sometimes trout are very picky and need close to the right fly. However, I think some get carried away with imitation. Will the wrong shade of olive keep you from catching the fish if you presented it well? I have my doubts.

I'm a big fan of the North Country Spiders. They aren't an imitation of anything but have worked for hundreds of years. I've gotten them to work when nothing else is working. Even during an obvious hatch. How is that explained? I believe it's because the fly shows life with the soft hackle. It looks like something to eat to the fish, so they do. How are attractor flies explained? They don't match anything. Have you ever got a Royal Wulff to work during a BWO hatch or a Caddis hatch? I have.

Until we can get a trout to talk. We don't know what they're thinking when they take or don't take a fly. Meanwhile we use what works.
Another good example of, "It depends". ;) I agree with you, not that my opinion should carry any weight.

Soft hackles are something I'm only just beginning to get into, want to learn more about and would like to dedicate a fly box to carrying.

With Royal Wulffs, this is the only thing I use when fishing for brookies.
 

old timer

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Yes, brookies are easy to please. I mostly fish for browns and they can be a bit more stubborn to please.

I've seriously thought of fishing the North Country Spiders exclusively all year long. Just to see how well they'll do. I know there are fishermen still doing that in the UK on the freestone north country waters. Very similar rivers to mine.
 

trev

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I am curious if you have tried fishing a 'hopper in mid winter? And how do you present the spiders relative to how you present the dry or emerger patterns during the hatch? all dead drift on/in the film, or some with a retrieve or swing?
 

old timer

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I am curious if you have tried fishing a 'hopper in mid winter? And how do you present the spiders relative to how you present the dry or emerger patterns during the hatch? all dead drift on/in the film, or some with a retrieve or swing?
No, I never tried a hopper in the winter but I don't think it's a good choice. Actually, I don't fish in the winter anymore. The older I got the more my hands get so cold I lose all strength in them. I remember getting my hands cold once and didn't have the strength to turn the key to start my Jeep. Now, I just fish in warm weather.

I mostly fish Spiders upstream like a dry. Maybe a bit up and across. I never use the across and down method but it does work. The flies are right under the surface and sometimes in the film. If I decide to fish them exclusively I may expand to different methods to decide what works best. I also just fish one fly. A bit more challenging. I may experiment with that too and use the traditional 3 fly cast. I hate tangles, so i'm not sure I can stay with droppers but i'll try it.
 

trev

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I don't think the fish recognize a 'hopper pattern as a warm weather terrestrial any more than they recognize a mouse pattern as a mammal. Instinctive opportunists they simply react to lifelike silhouette and movement, if I don't forget I shall try one next winter. I think I have used a beetle, but can't recall specifics, may have been for bass.

Back on the topic of relative size, it seems to me that the traditional hooks used built in a difference in length, I believe most books I read called for a standard length for dries and a 2XLong for nymphs of the same species?
My thought is that nymphs of different age groups and sizes might exist in a stream at any given time and a relatively younger smaller version might be more familiar to the fish on a daily basis.
Do the fish also perceive the tippet knot as part of the fly length?
 
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