K.now Y.our M.acro I.nvertebrates!

A small collection of resources for the macro’s. 

• Hudson Basin Quiz (Excellent Detailed Information)
• Macro Match Game (Simple, Fun)
• Iowater Quiz (It’s ok)

Finished work today and took another quick run to a stream almost in town. I did essentially the same routine as yesterday but yesterday being my first time taking samples today I found it easier to find what I was looking for. 

Things I found interesting:

-The curious amount of both Scuds and the Cased Caddis found in the picture above on the rock next to the mason jar. 

-The amount of another insect that I haven’t seen in a stream before, rather I used to see these in basements and under rocks outside. I’m curious if these were around due to the amount of decaying leaves in the water.  I compared them to scuds I found but they really are different. 

Answer: Sowbug – Research, Learn, Fish Smarter. 

- I found more stonefly and Baetis nymphs today as well as Trico’s I think… Am I correct in thinking these two below are two types of Baetis? Same shape, size, tail, gills just a different color. 

I’m still working on the best way for me to take better images with what I have at hand. I do want to learn about this, I just would rather save for a new rod or something along those lines. So, thats another afternoon tromping in the water. I found so many scuds it was crazy 10-1 for sure. I just had to state that again, I was surprised.

After work I dawned a set of hip-waders and a rain coat, no rod, no reel, and no fly box just a backpack, camera, and items for research. I drove to a stream that I spent much of my summer on. I figured this would be a good place to start gathering samples. The rain poured down as I walked the stream searching for the areas I wanted to sample. I brought several small mason jars to hold the captives until they could be more closely inspected at home. I stumbled through the water not really able to see the bottom because of the rain obscuring the surface of the water, as a result I almost stepped on a few trout that were held up in places that I hadn’t seen them in the summer months. I used a strainer, the handle broke almost instantly and I was forced to used my arm as a replacement to gather samples from shaken aquatic plants and kicked up substrate. The stream water and rain made me rather cold and wet but I had a hard time quitting. Two hours of taking samples, looking for the specifics I’ve been reading about and I decided to pack it in before catching something nasty.

I wanted to take a semi-scientific approach to this so I labeled my samples with the types of substrate or plant they came from, this to help in the future determine what lives where. I also started a field log with date, time, weather conditions and location. I plan to continue this behavior.

I brought my jars home and after gathering a few house hold supplies I was ready to begin my investigation. I did a rough count of each type of insect caddis, mayfly, scud, and what I believe to be midge pupa (maybe not). I measured in mm. many of the subjects and tried to figure out each species. I was pleased to see that my little stream camera takes decent close up images. 

In addition to the pictures above I found several examples of scuds and non-cased caddis. I believe that the picture labeled Nymph 2 is a Baetis. I compared it to images I have and I am pretty sure, it fits the right size in mm, and the right attribute with regards to the slightly shorter middle tail. I found no burrowers but I think I found both an example of a fast swimmer (Nymph 2 above), and a feeble legged crawler (Nymph 1 above). I found several types of caddis both cased and non. The image on the bottom right is of a caddis larva removed from its protective rock built shell. Note: this is not a tubular shell, it is the kind that looks like a tiny pile of pebbles stuck to a rock.

This was a good time.

p.s. After looking the photo’s over I think Nymph #3 is a Stonefly nymph, thoughts?

Caddis Fly Entomology Series Coming Soon

After reading Hatches 2 I was alittle dissapointed that I chose to research Mayflies first. I guess while fishing this summer was too intent on the fish to notice much else, including what they were really doing and eating, that I didn’t see a single mayfly. Honestly, I don’t want to admit that but hey, I’m going to be honest. I should say that I might have seen one in passing but not noticed it as such. So now after reading Hatches 2 and noting the majority of the relevant information I am moving on to Gary LaFontaine’s famous Caddisflies, because when I was slowed to the point where I would pick up a rock I found caddis larva. Also, while fishing late in the season I saw insects, white, two winged and with two very long spotted antennae circling over riffles. I spent twenty minutes and got rather wet getting a few of these to inspect . This I now know was a Caddisfly. Next season is going to be so different. 

Tying to Imitate

The following is a list of all the species of Mayfly that inhabit the waters around me and hopefully a comprehensive list of size and color for both surface dries and subsurface nymphs. The one major piece of advice that Hatches 2 presents is that the best way to catch a trout is to have accurate imitations tied for size first, shape second and color third. The book really emphasizes this point. I hope this helps myself and others. If there is a major discrepancy let me know please.

Dark Hendrickson (Ephemerella subvaria) Reddish brown to tan.  April-May

Natural 10-12mm Dry Flies: 10-12, Nymphs 10-12 Std. length.

Light Hendrickson (Ephemerella invaria) Tan with olive and yellow cast. Late May-June

Natural 7 1/2-9 1/2mm Dry Flies 12-14, Nymphs 12-14 Std. Length

Iron Blue Quill (Paraleptophlebia) Dark gray with maroon cast. Late May-June

Natural 6-8mm Dry Flies 16-18, Nymphs 14-16 Std. Length

Sulfur (Ephemerella dorothea) Orange to cream. Late May-Early July

Natural 6 1/2-7 1/2mm Dry Flies 16-18, Nymphs 16 Std. Length

White-winged Blacks a.k.a. Trico’s (Tricorythodes) Charcoal. July-Sept

Natural 3-5mm Dry Flies 20-26, Nymphs 18 Std. 24-26 Turned Up Eyes.

March Brown (Macaffertium vicarium) Mottled tan and brown. June-Mid July

Natural 14-16mm Dry Flies 8-12 4x long, Nymphs 10 Std. and 10 3x long.

Light Cahill (Macaffertium ithaca) Cream to tan. June-Mid July 

Natural 10-12mm Dry Flies 10-12 2x Long, Nymphs 10-12 Std.

The Hex (Hexagenia limbata) Tan-Dark Brown Late June-July

Natural 16-35mm Dry Flies 6-8 4x Long, Nymphs 4-6 3x Long

Yellow Drake (Anthopotamus distinctus) Creamy yellow Late June-Early August

Natural 13-16mm Dry Flies 8-10 Std, Nymphs 10 Std. & 10 3x Long

White Fly (Ephoron leukon) White Late August-Sept.

Natural 9-14mm Dry Flies 8-12 2x Long, Nymphs 10-12 Std. & 10 3x Long

Little Blue-winged Olive (Plauditus punctiventris) Pale yellow olive Late June-Oct.

Natural 3-5mm Dry Flies 20-28 Turned Up Eye, Nymphs 20-28 Turned Up Eye

Blue-winged Olive (Baetis) Grayish olive to dark olive March-May & Sept.-Oct.

Natural 6-9mm Dry Flies 14-18 Std, Nymphs 14-18 Std.

The Swimmers

The Darting Swimmers Families Baetidae, Siphloridae and Metretopodidae.

The two main species found in S.E. MN are two forms of the ever popular BWO. We have the Baetis and the Plauditus punctiventris. These are both found in the Baetidae family when identifying these nymphs from the other two families size is the best indicator. Siphloridae and Metretopodidae fall into the Large Swimmers while Baetidae fall into the much smaller size category. All have gills on the abdomen sections 1-7. One more overall comment about the Swimmers, they are the most varied group in the mayflies and emerge in cases all year round based on water temperature. One will find swimmers in almost every stream.

Little Blue-winged Olive (Plauditus punctiventris) 20-22 Pale yellow olive Late June-Oct.

In Hatches 2 this is listed as Pseudocloeon anoka but has changed since publication. These are still swimmers and so they will have similar nymphal traits to the other swimmers but one quick way to distinguish these from other Baetis is the tail. Plauditus punctiventris has only two tails while Baetis has three, also the abdomen is thicker on these nymphs. These nymphs are 4-5mm in length, I’m noting this size for my own reference. These nymphs will most likely crawl on grass or other items to get out of the water during a hatch. They are less likely to swim to the surface and then hatch. Fish downstream of extensive weed beds.

Blue-winged Olive (Baetis) 16-22 Grayish olive to dark olive March-May & Sept.-Oct.

These nymphs will be found in underwater foliage. The slender bodies as well as legs make them ideal for swimming through aquatic plant life. The baetis nymphs have three tails like most other but the center tail is much shorter than the outer two. Note that the baetis will emerger early in the season and late in the season. One thing I’m finding is that the exact species of Baetis is not listed and as there are several this will be a task for me this coming year to determine which exact species inhabit the waters around me. The greatest numbers of these nymphs are found in alkaline waters with a ph. of 7.5 or greater. Hatching will occur between 11am and 4pm in March-April when water temp exceeds mid 60′s. Typically one will see these on overcast days and as a general rule overcast provides some of the best BWO fishing.

The Hatch

I saw this video on the Moldy Chum’s Blog and on Mountain River Journal’s Blog and found it to be quite informative and very well done. As it is of mayflies I thought it fitting to post it here for my future reference. Note: The nymphs in the beginning are defiantly in the burrowers category note the tusks and if I’m correct these are Ephemera guttulata. My reasons for this identification are the shape of the tusk on the nymphs, and the distinct light yellow gill section and the much darker abdomen. Also the duns appear to match the larger size and color of the guttulata. Unfortunately, these do not inhabit my waters.

The Burrowers

The Slit Dwelling Burrowers Families Ephemeridae, Potamanthidae and Polymitarcyidae

The first thing that should be said about the three species of mayfly I chose to research is that both The Hex, and the White Fly are both excluded from the hatch chart I’ve been using and the reason for that is that in this area The Hex and White Fly produce substantial hatch numbers but in the warmer areas of the Mississippi River and the waters flowing into the river. As a result these two will most likely not be trout fly options but I am planning on trying to find these hatches next year and fish for bass or panfish willing to take the large flies. 

With that said the burrowers can be found by sifting through the silt in the stream. With the flowing water easily able to sweep the nymphs through your fingers Hatches 2 suggests bringing a jar that you can fill and shake to stir up the contents to find the nymphs. Burrowers are easily identified by the two large tusks on the head of the nymph. Looking at photo’s one can clearly see the difference between nymphs with and without the tusks.

The Hex (Hexagenia limbata) 6-8 4x Long Tan-Dark Brown Late June-July

The nymphs and indeed duns of the Hexagenia are among the largest of the Mayflies. Note the hook size recommended for the duns of the Hex in 6-8 4x long. What I know of these for this area is that they tend to emerge only on parts of the Mississippi and that a friend of mine fishes this hatch on the river for all kinds of warmer water fish. Hatches 2 gives one hint as to how to distinguish Hexagenia from other burrowers. The other burrowers tend to have deeply forked tusks while Hexagenia have longer more rounded tusks.  The main reason I believe that this is not a source of trout food is that the Mississippi has a better substrate that can allow them to have their U-shaped burrows in 3-6 inches of frim silt. 

Yellow Drake (Anthopotamus distinctus) 10-12 Creamy yellow Late June-Early August

Hatches 2 has this species identified as Potamanthus distinctus. Looking at the nymphs of this species one can easily identify them by the gills that line both sides of the abdomen of the nymph. They are very long and have bristles spanning the distance between them. Tying these nymphs one might consider using very short ginger hackle to represent the gills on the sides, perhaps trimming the top and bottom feathers leaving only the sides. Hatches 2 suggests using a Light Cahill dry pattern in size 10.

White Fly (Ephoron leukon) 8-12 2x Long White Late August-Sept.

The white fly is most likely not going to be a large part of my fly box but I have heard whispers referring to the Ephoron Leukon and in my efforts to be prepared for next year I will not over look this genus of Mayfly. These white mayflies will emerge just after dusk in August and September. On my Dusk til Dawn run near the end of a long day on the water I watched what I thought at first was Ephoron leukon but turned out to be a white caddis fly. Hatches 2 has little to say about this species but all the more reason for me to try and find it next season. 

The Clingers

The Fast Water Clingers Family Heptageniidae

These nymphs all have flat slender bodies, they also all have stronger legs to hold in fast flowing water. All the nymphs except the Epeorus genus have three tails, epeorus having only two. The mayflies that have substantial hatch numbers in S.E. MN are Macaffertium vicarium the March Brown and Macaffertium ithica the Light Cahill. I should note that the names of both of these species have changed from Stenonema vicarium and ithica to Macaffertium after further research demanded the shift in genus. Hatches 2 has them listed as Stenonema.

March Brown (Macaffertium vicarium) 10-12 Mottled tan and brown. June-Mid July

The March Brown is the larger of the two species that in habit Southeastern MN. According to my research the nymphs of vicarium are easily identified by the long tails in addition to the flattened body and strong legs. The tails on vicarium also splay at nearly 90 degrees. These nymphs are on average 16mm in length and are reddish brown. Vicarium move prior to emergence and one should examine rocks in ankle deep fast-moderate water for their presence. One should fish nymph patterns deep near the bottom as these nymphs either crawl or swim close to the bottom to find their emergence site. 

Hatches 2 makes it a point to note that the duns of Vicarium have a wing that slants more than other varieties at a nearly 45 degree angle. Hatching occurs throughout the day from 10am to roughly 6pm during the proper conditions. 

Light Cahill (Macaffertium ithaca) 12-16 Cream to tan. June-Mid July 

There is no picture of an ithaca dun on troutnut.com. I was however, able to find an image of a nymph. It’s interesting to me that troutnut.com has so little information on this species. I will be excited to find samples of these in the wild. 

Hatches 2 clearly states that the nymphs of both varieties here vicarium and ithaca need only be tied in medium and dark brown. Nymphs for ithaca should be tied in size 10-12. I’ve decided that when the mayfly series is over I will be posting a master list with sizes for nymphs and dries as well as color for all species related to S.E. MN. 

Anglers should note that days in June where the weather is cooler due to overcast or rain can produce day long emergence, on hotter days they will be concentrated in the morning. I like the fact that Hatches 2 notes that during this time of the year water levels are usually going down and that you should be careful while wading. 

I like the second image, making me want to try tying nymph with black thread down the hook shank then using perhaps lighter dubbing to simulate the dark center of the nymph.

Note: This information is as region specific (S.E. MN) as I can tailor it to be. It may be relevant to Northern Parts of Iowa and Southwestern Wisconsin. Also, if I forgot something/made a mistake in my information PLEASE post with what needs to be changed. This is for my benifit as well as visitors to W.F.F.

Looking at the 1st nymphal category “The Crawlers” there are five Mayfly species that have direct relevance to myself as well as other S.E. MN anglers. The following is a list in order by approximate hatch dates with condensed versions of relevant information. Thank You Troutnut.com for the excellent pictures.  

The Crawlers

Dark Hendrickson (Ephemerella subvaria ) 12-14 Reddish brown to tan.  April-May

Look for nymphs in the gravel and vegetation of slower meandering water. These nymphs tend to swim for a longer time and can be twitched upon retrieval. Hatching begins at 50-55 degrees. Hatches 2 points out the importance of poor weather slowing the duns down and providing for optimum fishing dun patterns. 

Light Hendrickson (Ephemerella invaria) 12-16 Tan with olive and yellow cast. Late May-June

These nymphs tend to prefer medium-fast water and like subvaria the nymphs use the current to choose an optimum emergence site. So they make for good nymph fishing because they are movin’! Hatching occurs in water from 50-60 degrees. Hatches 2 makes a big point of noting the size and color differences by a hook size or more between invaria, rotunda and dorothea. Meaning to me that I should tie these slightly larger because I’m looking specifically at invaria. 

Iron Blue Quill (Paraleptophlebia) 18-20 Dark gray with maroon cast. Late May-June 

My book says that the hook size for a dry is supposed to be 16-18. The nymphs tend to prefer quieter water. The gills are much larger on these nymphs than those of ephemerella.

Sulfur (Ephemerella dorothea) 16-18 Orange to cream. Late May-Early July

So my research in telling me that dorothea has typical ephemerella features and will spend time finding a spot to emerge. The book really makes a big point to note that dorothea differs from invaria by a full hook size and color. 

White-winged Blacks a.k.a. Trico’s (Tricorythodes) 20-24 Charcoal. July-Sept

I fished during trico action so I’ve seen these and they are small. The book and other info is right on for a 20-24 size hook. The nymphs thrive in streams with a p.h. of 7.5 and above. Nymphs live in the silt, sand and gravel in slow to medium current. As well as the aquatic plant life. Hatching between 52-56 degrees. Trico’s also have typically a very long period of emergence spanning over months.

Trying to keep this short but very useful. Hope my goal is accomplished. Also, I picked dun photos because I’m tying Compara-Dun Dries at the moment. Pictures coming soon.