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Lateral view of a Male Baetis (Baetidae) (Blue-Winged Olive) Mayfly Dun from Mystery Creek #43 in New York

Blue-winged Olives
Baetis

Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.

Mystery Creek # 199 in Washington

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Male Baetidae (Blue-Winged Olive) Mayfly Dun Male Baetidae (Blue-Winged Olive) Mayfly Dun

Lateral view of a Male Baetidae (Blue-Winged Olive) Mayfly Dun from Mystery Creek #308 in Washington

This dun emerged from a mature nymph on my desk. Unfortunately its wings didn't perfectly dry out.

7 Recently Added Photos

27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.

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Trout Streams
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New York
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The West Branch of the Delaware River

Trout Streams
›
New York
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The West Branch of the Delaware River

Landscape & scenery photos from the West Branch of the Delaware River

This fish almost got me into the coveted "20/20 club." It's a 20 inch brown caught on sulphur-flavored Galloup's Cripple tied on a size 18 3X-fine dry fly hook. It's also my biggest fish to date from the Catskills.

An 18-inch Catskill brown trout.

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

This is a common sight on the large Catskill rivers in early May, a mother goose guarding her nest. They like to nest on midstream islands where anglers are prone to walk from one fishing spot to another, and they do not back down. This one was hissing at me and I didn't want to get any closer.

From the West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

A tributary on the left approaches the large Catskill river on the right.

From the West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

Underwater photos from the West Branch of the Delaware River

The West Branch of the Delaware River in New York

The West Branch of the Delaware River in New York

Here's the head of a sea lamprey which migrated up the Delaware River to spawn.

The West Branch of the Delaware River in New York

These are red-spotted newts, Notophthalmus viridescens viridescens. Thanks Gonzo for the ID.

From the West Branch of the Delaware River in New York

Here's the body of a sea lamprey which migrated up the Delaware River to spawn.

On-stream insect photos from the West Branch of the Delaware River

Many beetles of this species were jumping around the rocks like popcorn on a mid-April afternoon. I'm sure they end up in the water for the trout at times.

From the West Branch of the Delaware River in New York

I didn't manage to collect a nymph, but here's the hollow shuck left over from an emerged dun, showing the basic pattern of the nymph.

From the West Branch of the Delaware River in New York

A thick mating swarm of Tricorythodes mayfly spinners hovers the West Branch of the Delaware near Hale Eddy one early fall morning. View the picture full-size and you'll be able to make out the wings and tails on most of those little white dots.

This was one of many such clouds visible all up and down the river. The mayflies were impressive, but the trout did not hold up their end of the bargain -- there was not a rise in sight.

From the West Branch of the Delaware River in New York

Closeup insects by Troutnut from the West Branch of the Delaware River in New York

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Female Ephemera guttulata (Green Drake) Mayfly Dun

Artistic view of a Female Ephemera guttulata (Ephemeridae) (Green Drake) Mayfly Dun from the West Branch of the Delaware River in New York

For years after I started this website, I was eagerly hoping to find a green drake to add to the collection, but I was never in the right part of the world at the right time. It finally happened on June 1st, 2007.

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Brachycentrus appalachia (Apple Caddis) Caddisfly Adult

Lateral view of a Brachycentrus appalachia (Brachycentridae) (Apple Caddis) Caddisfly Adult from the West Branch of the Delaware River in New York

I captured this specimen in the same color as this photograph, during its egg-laying flight. The emergers are much lighter.

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Female Helopicus subvarians (Springfly) Stonefly Adult

Lateral view of a Female Helopicus subvarians (Perlodidae) (Springfly) Stonefly Adult from the West Branch of the Delaware River in New York

I caught this female during her egg-laying flight.

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Female Drunella tuberculata Mayfly Dun

Lateral view of a Female Drunella tuberculata (Ephemerellidae) Mayfly Dun from the West Branch of the Delaware River in New York

I don't know for sure that this is Drunella tuberculata, but that's my best guess for now. It certainly has a different look and much more robust body shape from Drunella lata duns I photographed a couple weeks earlier, so I doubt it's that species. Using distribution records to eliminate other choices narrows this down to Drunella tuberculata or Drunella walkeri. Markings described for the abdominal sternites of the male spinner of Drunella tuberculata are suspiciously similar to those on this female dun. Also, this dun is 9.5mm long (my ruler pic isn't very good, but I'm basing this on measuring the real thing). The size range given in the old Allen & Edmunds keys for walkeri females is 7-8mm, while tuberculata is 9-11mm. For these reasons I'm sticking it in tuberculata for now. This is the only Drunella mayfly I saw all day. I scooped it off the water as it emerged at around 7pm from a big Catskill tailwater.

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Brachycentrus appalachia (Apple Caddis) Caddisfly Adult

Lateral view of a Brachycentrus appalachia (Brachycentridae) (Apple Caddis) Caddisfly Adult from the West Branch of the Delaware River in New York

The wings of this specimen were pale tan, almost white, when I collected it, and the body was of the lighter "apple green" from which this species gets its common name. Everything turned much darker by the time I got it home and under the camera. The wings look even darker in some of these pictures because the background is black and the wings are unusually translucent. You can see that in one of the pictures where the body easily through the wings. They're really a light, translucent gray, which is still far from the pale tan of the same fly when it was freshly emerged.

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Hydropsyche aenigma (Spotted Sedge) Caddisfly Adult

Lateral view of a Hydropsyche aenigma (Hydropsychidae) (Spotted Sedge) Caddisfly Adult from the West Branch of the Delaware River in New York

These big caddisflies were tempting trout as they wriggled out of their shucks, while others skated across the water at a medium pace, probably egg-laying.

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Female Stenonema terminatum Mayfly Spinner

Lateral view of a Female Stenonema terminatum (Heptageniidae) Mayfly Spinner from the West Branch of the Delaware River in New York

I was able to identify this female because I captured her while she was mating with an identifiable male.

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Male Stenonema terminatum Mayfly Spinner

Lateral view of a Male Stenonema terminatum (Heptageniidae) Mayfly Spinner from the West Branch of the Delaware River in New York

I positively identified this specimen under a microscope with a good key. It was one of the more common species in a generally light mixed bag of mayflies over a big Catskill tailwater last night. I swooped this one out of the air while it was mating with a female, so I can be certain about her ID as well.

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Female Ephemera guttulata (Green Drake) Mayfly Spinner

Lateral view of a Female Ephemera guttulata (Ephemeridae) (Green Drake) Mayfly Spinner from the West Branch of the Delaware River in New York

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Male Ephemerella needhami (Little Dark Hendrickson) Mayfly Dun

Lateral view of a Male Ephemerella needhami (Ephemerellidae) (Little Dark Hendrickson) Mayfly Dun from the West Branch of the Delaware River in New York

See the comments for an interesting discussion of the identification of this dun.

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Male Psilotreta labida (Dark Blue Sedge) Caddisfly Adult

Lateral view of a Male Psilotreta labida (Odontoceridae) (Dark Blue Sedge) Caddisfly Adult from the West Branch of the Delaware River in New York

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Male Epeorus (Little Maryatt) Mayfly Dun

Lateral view of a Male Epeorus (Heptageniidae) (Little Maryatt) Mayfly Dun from the West Branch of the Delaware River in New York

This Epeorus dun managed to emerge successfully even though it had apparently long several legs at some point and only partially grown them back.

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