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Blue Winged Olives

Baetis tricaudatus

Baetis nymphs are active swimmers. They hatch with water temperature as low as 46.
These bugs are multi-brooded  (Three broods per year.) They emerge by crawling.
You will see them in the morning and afternoon with the main activity from noon until evening


Nymphs are streamlined vigorous swimmers. They are light to medium olive-brown, size 18, with a brown head with pale patches on each side of mid-line. Their gills are slender with small gill plates. They have 3 tails; the center is shorter (half the size of the outer 2.) Tails are banded at mid length and the tips.


Baetis nymphs can be imitated with a size 18 hook, standard length. They are tied with an underbody of fine lead. Use olive thread, natural wood duck for the tail and legs, with a body dubbed with olive angora rabbit. The covert is made of iridescent green or blue feather from a pheasant or mallard, or peacock.


A pheasant tail also makes a good imitation.



If you would like to acqujre this pattern, click here.

A properly dressed emerger with no weight will usually out fish a dry fly. Try shallow riffles and weed beds.


The regulars at my fly shop found the following emerger pattern to be deadly.

Hook- sz. 18 94840
Tail-Medium Blue dun CDC or after shaft feathers.

Tie in a clump the length of ½ the hook shank and secure it at the
bend of the hook.

Body- Dub the thread with olive angora rabbit, wind the thread forward to form a thin tapered body. Stop two hook eye lengths behind the eye. Cover the hook eye length of hook shank in front of the body with thread as a base for the wing sprouts.

Wing Sprouts -Tie in a clump of CDC or after shaft feather to form the wing sprouts. They should be ½ the length of the hook shank, form the head and whip finish.



The natural has two tails as an adult.
We tie it on a #18 94840 hook.
Start the olive thread at beginning of hook point, wrap to the eye.
Wind the thread backward to the bend leaving 2 hook eye lengths of
bare shaft behind the eye. (We don't allow the body creep onto the bare hook.)
Over wrap toward the bend of the hook. Stop wrapping 1 thread width from
the bend.

Tie in a hackle clump tail. The 1st turn of thread holding the hackle clump tail (Light Blue Dun Hackle Barbs) goes directly over the last turn on the hook.
Using the finger snap/pinch technique to mount the tails, with thread tension near
the breaking point. Thread torque slides material to top of hook shank.
Tie in. (The tail should be as long as the length of the hook.)

The body is dubbed with olive angora rabbit) to form a
carrot shaped body. Stop the body when you reach the bare hook.
Wrap thread forward one hook eye length, Tie in a size 14 Blue dun hackle.
Wind 5 or 6 winds of hackle and tie off. Figure 8 with dubbed thread
drawing the hackle barbs to the top of the fly forming a hackle barb wing.
Tie off.




Female spinners crawl into the water under debris to lay their
eggs. We use the emerger pattern (above) to imitate drowned spinners.

These bugs are sometimes present without being apparent to the angler. Little Lehigh fly fisherman Gary Pyle has observed nymphs, duns and spinners under the dry side of partially submerged rocks. Apparently the complete life cycle occurred out of sight of the angler

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