Winter can be a tough stretch for some. Short days and damp, dreary weather is the norm for a lot of us riding it out north of the sunshine belt. Many others must contend with freezing temperatures on a daily basis. If the combination of these prevents you from enjoying the outdoors, the dreaded "cabin fever" soon sets in and the calendar watch is on.
Many folks will watch with great anticipation for those indicators that spring is approaching; American Robins returning to our lawns, Crocuses pushing through the turf, or hopes that a large Western PA rodent will not see his shadow. For the angler though, there is only one true harbinger of spring – and that would be the Blue-winged Olive. Baetis tricaudatus, B. vagans (reclassified), or any other members of the Baetis mayfly clan that are preparing to emerge en masse during late winter/early spring really get the fly fishing blood flowing and every angler needs to be prepared… NOW!
First off it pays to know your local rivers and streams as to the presence of Baetis and the timing of the hatch. In many instances the peak activity is sometime between early March and mid April, but latitude and altitude each play a role as does the type of flowing water (freestone stream, tailwater, limestone spring, other). Baetis are fairly easy to identify on the water or the wing; small mayflies, two tails, grayish/brownish/olive bodies and prominent "blue dun" wings (hence the common name often applied to them). They may be clumsily flopping on the surface or floating for long periods. Even those that do get airborne will be flapping by at nose level heading for what greenery there may be along the stream edges.
Secondly pattern size – in my experience hook size 18 is the right size for spring Baetis most of the time. Carrying additional patterns in sizes 16 and 20 is not a bad strategy however. Water fertility and amount of elapsed time between the fall brood and spring emergence help dictate the size of the naturals.
As far as preparing for - and covering - the hatch itself, I like to carry an assortment of nymphs, emergers, dry flies, and wet flies to mimic any stage the trout may be focused on. Let's look at them in sequence during typical Baetis activity.
NYMPHS:
Waters that have high fertility and accompanying weed growth produce tremendous numbers of these diminutive mayflies. Where present in large numbers, a good nymph imitation will produce fish year round. In tailwaters for example: you could do a lot worse than a standard 2-nymph rig with a Baetis imitating nymph and midge pupa imitation on point. And by "good" imitation I mean a pattern that fits the mold and you have confidence in fishing. Baetis nymphs are small, slim in profile, and active swimmers. A standard Pheasant Tail Nymph (Sawyer's version) in sizes 16-20 will serve the purpose most of the time. Keep in mind that heavily-pressured C&R trout are sometimes tuned into the stinging pain associated with gold beads, so carrying bead-free imitations for these types of waters is recommended. There are probably as many suitable Baetis nymph patterns as there are subspecies of the natural insect itself, so carrying and fishing a properly sized imitation that fits the slender profile should suffice.
No real secrets to fishing these imitations other than to say I recommend keeping the weight off the fly. It is difficult to weight this fly enough to reach holding trout during the high flows of spring without bulking up the pattern – although Charlie Craven's 2-Bit Hooker does a decent job of this. Otherwise just use split shot to get your imitations in front of waiting fish.
EMERGERS:
The only emerger pattern that I carry/fish specifically for this hatch is John Barr's Barr Emerger (BWO). If you are tuned into the hatch during peak season and slaying them mid morning with a nymphing rig only to have the fish suddenly turn off… snip off the point fly, lose the split shot, and tie on the Barr Emerger (BWO). More often than not the fish are moving up in the water column and intercepting the emerging nymphs. In fact you may start to see porpoise-like rise forms that should reinforce this selection.
DRY FLY:
I cannot think of another mayfly hatch where the trout willingly accept floating dun imitations more consistently than during early spring Baetis hatches. It really could be a combination of things that cause this to occur:
--First mayfly hatch of the season so the fish haven't been repeatedly pounded with dry fly imitations for several months.
--The "stunned dun" is commonly in full effect. Be it the cool weather, precipitation, biting winds, or all three combined… Blue-winged Olives tend to float for long periods of time after escaping their nymphal shucks – as opposed to summer hatches where mayflies blast from the surface causing trout to target those struggling to break through the surface tension.
It is a rare occurrence that I cannot dupe a trout with a flush floating dun imitation, so therefore the only dry fly I check into fly box inventory are Comparaduns, sizes 16-20 (again 18 being the most dominant), with a body of Superfine BWO dubbing. Comparaduns have two things going for them that make them a personal favorite; they float like a cork (no need even to apply flotant), and they are nearly indestructible when tied correctly. Even the best mayfly hatches are limited events, so the last thing you want to be doing is messing around with your fly to keep it floating, or (god forbid) changing flies while noses are poking through the surface.
WETS:
There are two wet flies that I must have with me at all times; some type of olive flymph (or soft hackle), and the RS2 dressed in Baetis colors. If trout stop taking the dry (and they will at some point), and are not vigorously accepting nymphs – I am tying on one, or both of these flies. Let's have a look at each:
*FLYMPH – Not everyone is familiar with this term coined by Pete Hidy. And fewer still will be carrying or fishing them. Use this to your advantage. This is the only other fly I would put in the emerger category as a challenger to the Barr Emerger and it sometimes will take trout on every swing following a hatch. Fish it like a typical wet fly or soft hackle and hang on! In fact after "the swing" let it dangle downstream and throw a few small mends to get some action into it. Be sure your rod is at an angle to the fly line position however as the takes will be sharp and can easily snap a tippet if the rod tip is pointed directly at the fly.
*RS2 – One of the most consistent search patterns outside of hatch activity. There are debates whether the RS2 imitates; a) an emerging nymph, b) a crippled dun, or c) a drowned adult (spinner)… I select "d"… all of the above!
True spinnerfalls are rare for this species as the females land on protruding rocks and crawl underwater to deposit their eggs. After their eggs have been jettisoned the females release themselves and drift off into the waiting jaws of trout. Once the spring hatch is well underway trout are accustomed to seeing these spent females in the drift and the RS2 does an excellent job of imitating this stage.
If I am certain that I am in the midst of Baetis activity, my nymphing "tandem" when arriving early-to-mid morning will be a standard nymph pattern followed by an RS2 on point. More often than not, I will begin the day with these two and end the day the same way after cycling through the hatch sometime between 11:00a and 2:00p (most occasions).
PATTERNS: – As mentioned, the "olives" of spring can range from hook size 16 through 20, but size 18 will be predominant in most cases.
One nymph pattern that I have a lot of confidence in is a no-name, Pheasant Tail spin-off as follows:
--Hook: Mustad 3906B – 3X HVY, 2X LG
--Thread: Veevus 14/0, brown
--Tail: Partridge fibres - brown
--Abdomen: 2-3 olive-dyed pheasant tail fibres
--Rib: fine gold or copper wire, counter-wrapped
--Wingpad (top): medium, black, holographic tinsel
--Wingpad (under)/Legs: 6 strands, black Krystal Flash, pulled forward-split-pulled back-and clipped
--Thorax: 4-5 natural pheasant tail fibres
Barr Emerger (BWO)
--Hook: TMC 2488 (scud hook), size 16
--Thread: UTC 70 - gray
--Tail (shuck): brown hackle fibres, tied in clump and clipped short
--Abdomen: Superfine dubbing, olive-brown
--Wingpad/Legs: dark dun hackle fibers, pulled forward-split-pulled back-and clipped
--Thorax: Superfine dubbing, Adams Gray
--Wingcase (optional): Holographic tinsel, small or medium (to match hook size)
Comparadun (BWO)
--Hook: standard dry fly hook
--Thread: UTC 70, rusty brown
--Tail: light or dark dun Microfibbets, splayed or split
--Body: Superfine dry fly dubbing, Blue-winged Olive
--Wing: fan of coastal deer hair, can be natural or dyed dun
Baetis Flymph
--Hook: Mustad 3906B – 3X HVY, 2X LG
--Thread: Veevus 14/0, brown
--Tail: Partridge fibres - brown
--Abdomen: 1-strand, DMC floss Nº 935, olive
--Thorax: natural hare's ear dubbing
--Hackle: 3.5-4 wraps of blue dun hen
--Optional soft hackle version: lose the tail and limit the hackle to 2 wraps just behind the head.
RS2 – Baetis style
--Hook: Mustad 3906B – 3X HVY, 2X LG
--Thread: UTC 70, rusty brown
--Tail: 2 Microfibbets, light dun, split
--Abdomen: 1-strand, DMC floss Nº 935, olive
--Wing: Hi-Viz, light dun (Nº 9), clipped short
--Thorax: Superfine dubbing, Adams Gray
These patterns have worked well for me; however, there are many others that are very effective as well in all of the above categories. If you've got good intel or just plain have more confidence in other imitations, by all means make the substitution.
Although this public service announcement is focused on the early spring clan of Baetis species. There are many subspecies of this family that can (and do) emerge almost year round. Winter hatches are unusual, but not unheard of. Over the summer however, and then again in the fall, you can expect to see these small "olives" at any time – especially during overcast and/or rainy conditions. In fact the second largest wave of Baetis activity arrives in the fall. These are actually the second brood from those hatching in spring. General rule of thumb is that the second brood will be a hook size smaller than the spring hatch, but nothing is set in stone. Carry an assortment of sizes.
I can't stress weather conditions enough. More so than other mayfly species (it seems), Baetis are particularly fond of lousy weather. If you're the type to look out the window and bail on a trip to the river because of leaden skies, rain, snow, or wind… you may be missing out on some absolute blizzard hatches of Blue-winged Olives.
Now you will have no excuses not to be prepared when the Blue-winged Olives suddenly appear in the coming weeks. Rafts of tiny gray sailboats pass by as noses start to poke through the surface. You do not want to be out there helplessly tossing the midge pupa patterns of winter when the trout throw caution to the wind to greedily gobble down the first major mayfly hatch of the season.
Tight lines!
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