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Home » Ebb and Flow Blog » Iso Time!-Big Mayflies for Big Trout

Iso Time!-Big Mayflies for Big Trout

brown trout, Catskill fly fishing, Delaware wild trout, Driftless Area, Dry Fly, emergers, Fly Fishing, Hallowed Waters Journal, Hex Hatch, Isonychia hatch, mayfly, Michigan Fly Fishing, Michigan trout streams, New Zealand style, Nymphing, orvis fly fishing, Pere Marquette, Selectivity book, The Brown Trout-Atlantic Salmon Nexus Book, Trout, trout spey, Uncategorized / June 28, 2021 by Matthew Supinski

(The Compara CDC-Iso Crack is a deadly pattern inspired by Caucci & Nastasi’s “Hatches” book. Their Spectrumized Dubbing allows for the incorporation of all the tonal colors in the hue of the complex Isonychia color spectrum. As the CDC reflects the smokiness of the wings perfectly, yet many still prefer the durable and floatability of Caucci’s Compara- coastal deer hair. The key with CDC is to tie many clumps together to improve floatability, and denote wings fluttering/drying. The best floatant is Loon’s “Lochsa”. The Isonychia hatch is big bug mayfly magic in daylight hours- know this hatch from the benthic nymphs to the surface emergers and dries and you will score with your 20 inch plus dream trout!-authors tie and image)

It’s that “white-gloved howdy” magic time. That gorgeous (can’t help it folks!, I adore mayflies if you haven’t noticed) purple/green/mahogany mayfly with dainty evening reception gloves and smoky wings brings theories on selectivity and fly selection’s hue and tone differential to a colorful fly tier’s conundrum.

(The Beautiful White Gloved Howdy-Iso-JG Miller image)

The magnificent meaty “Iso” : (i.e. Isonychia bicolor, sadleri, harperi) is a big chunky meal for a trout and a mayfly hatch for normal diurnal anglers not interested in growing fangs from a blood thirsty vampire/ night stalking life style as with the all-night chase when it comes to the crazy Hex hatch gig.

( A lower Klamath/California Iso- Utyer image-FlytyingForum,com)

The hatch is an East Coast and Midwest North American staple. It prefers hatching temperatures in the upper 50’s F to the mid-60’s. But is also found in good fishable hatch matching numbers in small pockets in the west , mostly in California and upper Montana, especially on the Klamath River ecosystem and western Canada. They also are found east of the pond to the U.K. and north/central Europe with the Isonychia Eaton, alderensis, arabica and berneri

( Isonychia range globally-c/o www.gbif.org )
( A serious truttasaurus West Branch Delaware brownie taken at gentleman’s hour’s ( 12 noon) by “THE bug dude” himself: Johnny Miller, on an Iso emerging /swimming nymph. Iso’s are prominent all over the east and Midwest and is one hatch you should seriously get to know from June through September-author image)

As I featured the nocturnal Hex hatch in my previous blog, here is an alternative “big bug” fix that can allow you to keep your spouse or significant other you just started dating- a gentleman or lady’s sport as the Brits I love so much would say. Besides darling, poached salmon with a dill sauce, tea and Butter Shortbread cookies with strawberries and crème fraiche, along with sipping fine sherry /cognac doesnt usually properly go down with the servant staff too well at the river estate at a 3 am dinner service eh? Therefore Iso’s are a good alternative big bug after nights on end has you burned-out, groggy and lacking sleep, and your spouse coming into your bedroom and opening the window shades at 3 in the afternoon and saying, “are you going to waste your life away sleeping all day, drinking and fishing all night?- you are not a normal person anymore and need counseling to stop that big trout addiction!” ( I know trust me!… those words sound familiar LOL?)

(Isonychia- the Lead-Winged Coachman is an iconic mayfly of early summer that turns large trout on the hunt in a ravenous manner. Get in on the action now!-JG Miller image)

Isonychia bicolor and sadleri are the two larger versions (#8-12) with the sadleri more a smaller fall emerger from August through October. Their other names are Slate Drake, Lead winged Coachman, Dark Dun Variant and Borchers. They like rocky and gravel rivers and streams and hatch from mid-depth benthic environments towards the shorelines as we will importantly discuss. My first experiences with these beautiful mayflies was while a young boy in western NY state on some of the Alleghany trout streams like the Wiscoy, Cattaraugus Creek and Oatka. I also saw them at dinner hour at our summer cottage along the Canadian shore of Lake Huron/ Georgian Bay area’s wild trout streams. My good Canadian friends Larry Halyk and Jack “the trout” Imhof talk about the brown drakes and other big mayflies in the “Aristocratic Drakes and Hex” piece article in the current issue. But they are truly hallowed and worshiped in my home here in Michigan and are found in prolific numbers and have inspired fly patterns like the famous Borchers.

( Protegee Brett Howard, a very good friend, inspiration for anglers and super fishy trout, salmon and steelhead fly swinging addict, has taken his passion to the highest level and has become a true master of the dry fly and streamer gig. Here is one of the most beautiful Truttasaurus beasts that took an Iso emerger on a northern Michigan trout stream-B. Howard image)
( Th beautiful wild trout streams of my youth of the Niagara Escarpment along Huron/Erie in Canada- big drake water-Imhof/Halyk)
( Prime Drake/Iso water -Imhof/Halyk )
(Original Isocaine wiggle- a devastating pattern swung trout spey style when searching trout streams you are not familiar with-recipes in the spring/summer issue of Hallowed Waters Journal-www.hallowedwaters.com)

Later in life at our family’s summer home in the Catskills , the Iso hatch was a very important event from June through September and brought up big browns on the Neversink and Beaverkill and rainbows on the main Delaware. Here you could enjoy the emergence on the river and have a chance at a big brown and be back at the lodge for dinner in civilized hours.

(Two gorgeous browns from the Neversink ice-cold tailwater on the Isonychia hatch at “happy hour” time- no “things bump in the night” here and a blessing as we get older with some having eyesight issues in daylight, nevertheless darkness!-author images)
(A stunning “ground-zero” wild brown from the Neversink tailwater on the Nexus Isocaine wiggle. This section has an amazing Iso hatch all summer. Fyi: “ground zero” refers to the first plant of brown trout from Germany in the western hemisphere that took place in NY and MI in 1884-1885- happened on my Michigan Manistee forest streams and on the Neversink’s Aden Brook tributary-author images)
(Though you will find very little information on the Neversink, since the other Catskill Rivers get all the attention like the Beaverkill, Delaware and Willowemoc, the article I wrote in “Fly Fisherman Magazine” years ago has all the details and skinny on this iconic historical river where Gordon and Hewitt and its wild browns and brook trout make it one of the finest national treasure rivers in America)

One of the best east coast Iso hatches I’ve experienced was on the Bard-Parker pool of the junction between the west and east branches that my good friend and author of his new book on dry flies, Paul Weamer , would sit on the tailgate, smoke cigars, drink single malt Scotch and listen to Pink Floyd blaring in the parking lot, as we waited for the Iso hatch to occur like clockwork. Here we had many an amazing night on 16-22 inch wild browns and lightning fast rainbows that pealed backing off of large arbor reels like dime bright chrome steelhead.

( Junction Pool (Bard- Parker) and “Second Heaven braids” below- perfect Iso weather-author image)

In true Catskill Delaware style on many a night we locked horns and shoulders with older grumpy curmudgeons that hated any company ( one night an old timer started to give me grumpy lip and “told me to go back to Cairn’s Pool on the Beaverkill!- btw: them is “fight’ in” words and an insult in the Hebrew Himalayas bible fyi , all because I was getting too close to him being only just a mere half-mile away btw-da!,… Boy!, did I let him have it!- in a true Polish warrior fashion 🙂 And one glorious evening I hooked and landed 4 nice browns and bows in the 18-21 ‘inch class when the Iso hatch was on big time time and every “Mr./Mrs. Big” was poking their nose aggressively in the meniscus. That evening I totally out-fished and “Iso-educated” my late-great idol and spiritual Salmo salar mentor: Art Lee. Art was a master at all things Atlantic Salmon and Catskill’s trout and I pray that the younger generations seek his writings out which I have so proudly done in my “Nexus” and “Selectivity” books, and will always mention. If there is anything I feel total regret and sadness with in today’s new “YouTube/social media ” generations, is that we don’t honor, study and learn all we can absorb from the amazing wisdom and writings of the dead sadly.

( My good friend Paul Weamer’s new dry fly opus is being released any day now- look for it to be a new modern masterpiece)
( As my good friend “big Al” Caucci (a.k.a. the Godfather of the mayfly hatch), who was so kind to write the forward for my “Selectivity” book, and said so prominently in the Caucci/Nastasi “Hatches I and II ” books , which describe the Iso nymphs as: ” Our aquarium observations show that these nymphs rank among the swiftest of all mayfly naiads” -JG Miller image)

The Iso hatch matching magic starts at the nymph emergence level. Since they are fast swimming and undulate their bodies and gills quickly, my Isocaine nymphs perfectly imitate that movement which trigger big trout on the look-out. The nymphs swim towards the shoreline seam water and will hatch crawling on rocks, or some emerge from the water’s surface along the bubble line periphery . By using a tungsten head wiggle IsoCaine and swinging down-and-across big trout give-off vicious strikes- set the hook gently and like swinging for steelhead with a slip strike. This is my favorite type of wet fly swinging -trout spey style using 12-13 foot/ 3-5 weight rods and something to be perfected and utilized with deadly efficiency.

( The Isocaine wiggle-incorporates undulating swimming movement. The more classic Iso nymph below is extremely deadly and less complicated also. Both patterns and recipes are in the “Aristocratic Drakes and Hexs” article in this issue of mayfly celebration)

It is important to pay attention to many details during the Iso season. First watch your wading and where your presentations will be fished effectively. Too many anglers wade on the fish feeding tight to shore. I learned that lesson years ago fishing with my Delaware Sensei guru/guide Miller. Here he figured it out New Zealand style as all the “sheep with fly rods” were standing waist deep in the pools and runs and we were hunting the shorelines catching 20 inchers literally behind their backs. Rule is “if you are over your knees wading, you are messing up good Iso water” where eating big trout are looking for swimming emergers near the shoreline”

(Miller points to shore rock structure where Iso’s like to emerge- we caught more 18-20 inch plus trout that day in July in mid-noon hours hunting the shorelines and fishing Iso wiggle nymphs-devastating stuff!-author image)

Iso’s will hatch anytime from noon until midnight, but prime emergence is always around dinner time. They love cloudy days but also emerge in bright sunlight, unlike BWO’S. Swallows love to chow on the meaty helicopters of the flying Iso’s so as soon as you see them swooping near the river the Iso hatch is on and you will we see Iso’s hatch and head for the trees- sometimes those darn swallows will eat every bug, and we wonder why their shortage is getting greater year after year sadly- we often cheer for the Iso’s to make it to shore, as sadly a swallow scoops them up just as they are ready to touch down on a tree.

( In this spring/summer issue, Delaware /Cross Current (Orvis Guides of the Year Service) Anita Coulton shares her secrets and fly patterns for the Isonychia hatch www.crosscurrentguideservice.com. Anita knows her Delaware and booking a trip with her and spending the day with her and her big browns and bows is money well invested – her wisdom is well worth following in the
“Mayfly Aristocracy- Drakes and Hex” mega mayfly piece at www.hallowedwaters.com)

Once they emerge and are on the water, their twisting/fluttering to break loose is quick and takes notice from the trout. But there are days when the trout want them dead-drifted, or with just a little twitch. The bigger the bug, the more finicky trout take them- especially big browns that always show a little caution to big mayflies.

(Author’s Nexus Iso: new materials from Hemingway/Frosty Flies make for a killer selectivity presentation that is deadly to uber-fussy fish. The materials are foam and thin cellophane that don’t twist like stiffer true-form materials- check out www.frostyfly.com, tell them I sent you!)

So…if you want to master the best hatch that is just gearing up for the summer and fall, and need the total in-depth skinny and then some, the new issue of Hallowed Waters Journal is a mayfly powerhouse packed with articles devoted to the dry fly /hatch matching experience. The “Aristocratic Mayflies” piece has it all for each big mayfly, along with patterns and recipes- most importantly tactical analysis you wont find in other magazines out there! Come to www.hallowedwaters.com journal today!, and subscribe. Don’t let the passion and journey have you buried in often meaningless and uninformed cyber information/ social media chatrooms… go to the source and learn from the years of wisdom our experts have!- also put your time in and pay your dues on the water as we at Hallowed Waters Journal do!-it’s the best classroom!

(This 25K article doesn’t leave one stone unturned when it comes to Iso’s and big mayfly hatch matching)

Next blog: “in Search of Summer Silver”

Cheers!

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