Midge
Chironomidae spp.
- Peak week
- Year-round
- Intensity
- Heavy
- Time of day
- Midday
- Water temp
- 32–60°F · peak 40°F
Top flies
Griffith's Gnat #20-24 · Zebra Midge #20-22 · WD-40 #20
Reliable winter fishing
Hatch calendar
South-central PA limestone with the most famous catch-and-release stretch in the state at Allenberry. Reliable Sulphur hatches and a strong year-round midge fishery.
Fishing regulations change every season. This page is a summary maintained by Bield — bag limits, exact dates, and species-specific rules must be verified with TCO Fly Shop before each trip.
What's hatching now
Chironomidae spp.
Top flies
Griffith's Gnat #20-24 · Zebra Midge #20-22 · WD-40 #20
Reliable winter fishing
Baetis spp.
Top flies
Parachute BWO #18-20 · CDC Comparadun #18-20 · Pheasant Tail Nymph #18
Spring emergence
Ephemerella dorothea / invaria
Top flies
Sulphur Parachute #16-18 · Sulphur Comparadun #16-18 · Sulphur Sparkle Dun #16
Hydropsyche spp.
Top flies
Elk Hair Caddis #14-16 · X-Caddis #14 · LaFontaine Sparkle Pupa #14
Ephemerella subvaria
Top flies
Hendrickson Parachute #12-14 · Red Quill Spinner #12-14 · Pheasant Tail Nymph #14
Brachycentrus spp.
Top flies
Elk Hair Caddis #14-16 · Henryville Special #14-16 · LaFontaine Sparkle Pupa #14
Stenacron / Leucrocuta spp.
Top flies
Light Cahill Parachute #14-16 · Cahill Comparadun #14 · Light Cahill Spinner #14
Full year calendar
Each row is a hatch species. Bar color = type, opacity = intensity, peak month outlined. The current month is highlighted on the timeline.
Hatch species on Yellow Breeches Creek
Chironomidae spp.
Water-temperature trigger
Top fly patterns
Year-round food source — the only consistent option on tailwaters in winter. On cold sunny days look for noses sipping clusters in slow water.
Baetis spp.
Water-temperature trigger
Top fly patterns
Most reliable Eastern hatch. Two emergences — spring (March-April) and fall (September-October). Best on overcast, drizzly days.
Ephemerella subvaria
Water-temperature trigger
Top fly patterns
First substantial mayfly hatch on most Eastern rivers. Spinner falls in evening can be as productive as the dun emergence.
Brachycentrus spp.
Water-temperature trigger
Top fly patterns
First major caddis emergence of the year. Look for clouds of small dark caddis above riffles in late afternoon.
Ephemerella dorothea / invaria
Water-temperature trigger
Top fly patterns
The most important mayfly hatch on Eastern rivers. Reliable emergence + spinner fall every evening for 4-6 weeks. Match the spinners with rusty-bodied patterns.
Stenacron / Leucrocuta spp.
Water-temperature trigger
Top fly patterns
Pale yellow-cream mayfly. Less intense hatch than Sulphur but reliable across many Eastern rivers in late spring through early summer.
Hydropsyche spp.
Water-temperature trigger
Top fly patterns
Workhorse summer caddis. Heavy emergences and egg-laying flights at dusk through summer. Drop a soft hackle on the swing during the evening.
(beetles, ants, hoppers)
Water-temperature trigger
Top fly patterns
Not a hatch but the most important summer trout food in many Eastern systems. Fish tight to grassy banks and overhanging trees. Hopper-dropper rigs are deadly July through September.
Tricorythodes spp.
Water-temperature trigger
Top fly patterns
Tiny black-bodied mayfly. The spinner fall — not the dun emergence — is the main event. Look for clouds of spinners over flat water at sunrise.
River info
Bield Fish reads USGS gauges, watches for the trigger window, and pings you when Yellow Breeches Creek hits the temperature for your target hatch.
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