Shrimp anatomy for the fly tyer
Having seen, tied and fished shrimp flies for many years, Martin feels a need to do a little lecture on the real appearance of shrimp, especially targeted at fly tyers.
But having seen and fished shrimp for so many years, I feel a need to do a little lecture on the appearance of shrimp, because the different interpretations of this small but important food item, brings us all the way from huge things that look like paint brushes on steroids to small things that look more like colorful earrings than a natural animal.
I know that many of these flies work just fine, and that there are no set rules that say that flies have to be perfect imitations. But just to set the record straight and to inspire fly tyers, here's a small lecture on shrimp anatomy.
My local shrimp
I will not venture into a lot of Latin names or discuss variations of the local species in detail or spend lots of time on differences between cold and warm water and many other aspects of the world of shrimp.
My lecture is very general, and deals with the average, small shrimp. There are local variations regarding color and other things, but in general the shrimp that I cover are quite alike apart from some color differences.
The observations below are made on the basis of my local Baltic shrimp. I am fully aware that there is a colossal variation in shrimps if you traverse the world, but this is primarily about the kind of shrimp that I need to imitate to fish for my local seatrout. This will also cover shrimp in many tropical flats as well as shrimp found in colder waters on Pacific and Atlantic coasts.
Size
The shrimp I'm covering are small animals, typically in the 2-5 centimeter range or about an inch or two. Shrimp can grow up to 30 centimeters or 12 inches or so, but such monsters are hardly interesting to imitate with a fly.
They are in general quite uniform in size, and although there are smaller and larger specimens, even of the same species, there are no "baby shrimp" or gigantic individuals. Like most crustaceans, fully grown shrimp do not grow from small ones, but they come from larvae that molt and grow in steps until they reach a certain size. They cannot grow continuously due to their exoskeleton.
Look in your local water to assess the average size of shrimp, and use that as a measure for your imitations.
These are very delicate animals with slim bodies, thin legs and antennae and just a few bright and obvious features like egg sacks, internal organs, colored bands, segmentation on the shell and oftentimes very visible eyes.
But as a whole the animal is very glassy and almost transparent.
Color
Color varies tremendously, but in keeping with the above, isn't very dense or dominant. Some tropical species are very brightly colored with orange, pink and other "non-earth" colors. If you look at cleaner shrimps you will find really bright neon colors. Their aim is to be seen!
The bright colors and obvious patterns are more common in warmer waters, while cold water shrimp are less visible.
But our local cold water shrimp and many tropical shrimp living on sand and silt flats have colors that come from the earth-tone specter like dull brown, gray, olive and the like maybe with a bit of brighter green, blue, red or orange mixed in.
From the back we have a flat fan-shaped tail, a tapered and very clearly segmented abdomen often with a "hump" in the center and a row of smaller swimming legs underneath, a thorax with some visible internal structures and front walking legs as well as some mouth parts attached underneath and a tapered head with a rostrum (thorn), obvious eyes and the antennae. Some shrimp also have a predominant egg sack underneath.
The basic shape is that of a very elongated and very flat N. Some are flatter, and some have an obvious hump and a very bent shape.
Imitating a shrimp
As fly tyers we can choose to worry about various parts of the shrimp anatomy. I see a number of significant characteristics that I think define shrimp to the predator:
- Color and transparency
- Overall size and body shape
- Legs and antennae
- Eyes and other "dark structures"
- Movement
1) Color and transparency
A shrimp imitation has to be transparent! At least if it's going to look the least like one of the shrimp that I see almost every time I fish.
The glassy appearance of the animals is the first thing to notice, and an obvious trait to imitate. The best looking shrimp patterns do exactly that, and you see a couple of examples on the adjacent pictures. A shrimp body like that is an obvious part to build with epoxy, hot melt glue or light cured resins - LCR's. All of these allow for shaping the body and all end up translucent like the natural animal.
Shape is hardly as critical, but the hump on the abdomen of our local shrimp is a very important feature and all shrimp also have a thorn on the forehead, a rostrum, which is very characteristic. Select a curved shank hook, and the body shape is helped on the way.
Many shrimp patterns feature a loose shell on the top of the animal. On the real shrimp it wraps around the whole body and completely encloses it, looking as one, smooth unbroken piece. The segmentation is also more obvious in color than it is in shape, with no clear dents or creases in the outer shell. So segments should be visible, but the outside of our fly should be smooth.
3) Legs and antennae
A shrimp sometimes seem to be all legs and antennae. On most animals these features are very distinct and very visible and both antennae and legs are often very shiny and with colored bands that make them quite visible. Placement and orientation of these appendices is also important.
The shrimp also has different mouth appendages as well as claws, but for the sake of imitating these limbs, we don't need to worry much since they look like and are positioned much like the walking legs, and hard to tell apart from these.
Feather barbs are an obvious choice for the small swimming legs while rubber legs are the right choice for the walking legs.
Antennae can be made from stripped feathers, rubber, flash straw or other similar thin, almost clear materials. On most of our local shrimp, the antennae are in fact not that long or visibly dominant.
4) Eyes and other "dark structures"
Most shrimp have some obvious "dark structures": eyes, intestines and an egg sack.
The eyes on the side of the head are mostly black and pretty visible. They vary in size, but are quite large on many species. On some species the eyes are flush with the body on others they stand on "stalks". Black monofilament eyes are the perfect imitation in both cases.
Inside the thorax we see some internal organs and many shrimp have an egg sack underneath between the swimming legs, oftentimes colorful and at least very visible. Both these features can be imitated with dubbing, but some tyers actually make small balls to imitate the eggs.
5) Movement
The movement can be hard to imitate, but is never the less an important part of the animal. The swimming legs oscillate in rhythmic and wave-like motions, the front legs and antennae work in more erratic patterns.
The animal as a whole has a slow forward swimming or walking motion and a very quick and sudden backwards escape motion.
Regarding movement, we have to induce this by stripping in the fly in a pattern that mimics the natural. Slow, even strips interchanging with sudden jerks will make the shrimp fly act more shrimpy. You can also let the fly dive to the bottom and rest there before stripping. Shrimp will spend most of their time moving on the bottom, on rocks, on weed or on some other structure.
Creating an imitation
With outset in the above you can start making an imitation. There's a whole bunch of these already, but only few that really imitate (like in look like) a real shrimp. I know very well that the fish don't care much about the precision in our imitative flies. After all they do take Glitter Shrimps and Pink Pigs, which only with a wild stretch of imagination look like a shrimp. But if you want to fish with something that you say look like a shrimp, you need a correct size, proper translucency, fairly short legs and antennae and eyes that sit close to the body.
Should we imitate?
Now, I have said it before, and I'll gladly say it again: I'm much more for the suggestive than the imitative. 95% of my flies look very little like any natural. Magnus, Red Tag, Klympen, CDC&Elk and all the flies that I like, suggest more than they imitate. Still they are definitely perceived as something edible by the fish, but definitely not because they perfectly imitate anything the fish eat.
And that's fine with me. I'm very pragmatic. When it works, I'm happy.
I'm much more for the suggestive than the imitative
But if you want to imitate, and find that it's important to do so, please make your flies look like the real thing - just a little. Look at tyers like Oliver Edwards or our own Radoslav Kiskinov whose flies are very good imitations, tied to look like the real thing and still be useful in practical fishing.
Thanks to Thomas Madsen from flueopskrifter.dk, Rune Westphal from Seatrout flyfisher, and photographer and author Michael Jensen for use of their pictures and thanks to Kern Lund, Kasper Mühlbach, Henning Eskol, Ken Bonde Larsen, Jesper Malmberg and many more for use of flies and/or pics.
No patterns!
There will be no recipes for any of these many shrimp flies in connection with this article. The aim of the article is not to provide a materials list for the perfect (or imperfect) shrimp fly, but to inspire you to look at your shrimp flies with new eyes.
We have tonnes of shrimp flies on GFF, and there will undoubtedly be more in the future - maybe even some of the many new flies shown on this page. Below you see links to shrimp patterns on this site, including some of the ones shown above.
More shrimp on GFF
A shrimp theme page.
Comments
all the flys on this
all the flys on this site are really good,what I would like to know is if and were I can buy the materials to tye these patterns,i love to tye flys that look like they are supposed to be, realistically,can you give me any ideas on were to get these material,s thank you
I tied some near per
I tied some near perfect patterns last year for the Bahamas using normal materials and Loon UV Clear. Nada. They were ignored by herds of bones. I went back to gotcha's and crazy charlies (tan arctic fox wing with pink head) in size 6 and... Those flies look like nothing that I have seen in the ocean but are amazing! My guess is that the movement of the fox wing suggested life whereas the "perfect" flies did not.
And, almost all of my hookups were not on the strip but when the fly stay on the bottom with the current moving the wing. I kept a tight line and could feel the take and missed very few strikes.
What color wing to use? I suggest using the color that best matches the bottom/sand where you are fishing. I found that my darker Keys flies were useless as the sand in our area was an almost white beige. We also discovered, at low tide, the flats were covered with this color crabs just larger than a US dime. We moved to size 6 and 8 flies and had much more success. Match the hatch! Just like when fishing a new stream and turning over rocks to assess insect life to match, spend some time on the flats determining the color and size of the prey and your luck will increase.
I am not a marine biologist but assume that prey in an area spawn at about the same time and their offspring grow from very small to full size at a fairly uniform rate. So, determine what size is predominant at the TIME you are there and match that size.
I hope that a biologist reads this and opines on my assumption!
Roger
Great and very inspiring
Great and very inspiring article Martin. One of the things I have come to think about when it comes to shrimp flies is that these very realistic imitations often look entirely different when they get wet which - after all - is how the seatrout sees our flies.
The realistic shrimps tied with a bunch of materials (some of them quite expensive) and a lot of details like rostrum, antennae, segmented back, legs etc. does look convincing when they sit in our vice. However when they are put in water, and even more when they are retrieved through the water, they do, in my opinion, not always look that realistic. Don't get me wrong: the are off course able to catch fish, and occasionally I tie them my self because I simply like to tie flies. However - and quite in line of your Mundane Fly project - I like to keep it simple, and I haven't yet come across a fly which is more realistic in the water than the STF shrimp - at least when you take into consideration how simple it is.
It goes like this:
"Tail": small bunch of STF dubbing.
Eyes: 2 pcs. of burned nylon line.
Body: STF dubbing in a dubbing loop wrapped around the hook.
Brush the whole thing up - and go fishing.
When it's wet the brushed dubbing gives the fly a transparent look, wich in my opinion resembles a shrimp very well.
Tight lines.
Søren.
Some great info and
Some great info and flies here. It appears that the hook position/orientation is widely varied among all shrimp patterns. Any input on this aspect of hook orientation with respect to the shrimps body on how the shrimp will move/sink throughout the water column? Can you correct weight imbalance after one is tied, or are you sometimes left with a wonderful looking yet useless shrimp?
Great imitations Mar
Great imitations Martin! I am tying some shrimps for the caribbean waters and this article is perfect.
Theory
I love these fly-tying theory articles. I find them much more useful to my development as a tyer and fisherman than simply memorizing a few specific patterns. Thank you.