Yellowstone Country Hatch Chart

	Baetis Mayfly	PMD Mayfly	Hydropsyche Caddis	Brachycentrus Caddis
SEASONS	Spring and Fall	Summer	Summer (and Oct on Firehole)	Spring
SIZES	#18-22	#16-18	#14-16	#14-16
NYMPH/LARVA	Pheasant Tail	Pheasant Tail, PMD Nymph	Olive Brown Free-Living Caddis Nymph	Dark Cased Caddis Nymph
EMERGER-DEEP	N/A	N/A	Brown/Yellow Deep Sparkle Pupa	Brown/Bright Green Deep Sparkle Pupa
EMERGER-SURFACE	Sparkle Dun, Baetis Soft Hackle Emerger	Sparkle Dun, PMD Emerger	X-Caddis, Brown/Yellow Emergent Sparkle Pupa	X-Caddis, Brown/Bright Green Emergent Sparkle Pupa
ADULT	Sparkle Dun	Sparkle Dun	Tan X-Caddis	Olive X-Caddis
NOTES	Emerge best in cool, overcast conditions. Light rain or snow is perfect. #18 Tricaudatus - nymphs good swimmers; emerge generally 1-4pm; spinners unimportant #22 Punctiventris - tiny nymphs unimportant; emerge any time 10am-5pm. Look for smooth, slow, moderate flows. Important on Firehole, Madison, and Henry’s Fork	Yellowstone's single most important mayfly; emerge most comfortable time of day (normally 11am); use pheasant tail on Madison, floating nymph on Firehole; spinner falls in morning	Most important caddis; emergence in evenings often lasts several hours June 5 – August 15^th on Madison outside the Park Peak emergences in May, June, and October on the Firehole	"Mother's Day Caddis" is first major caddisfly of year; active in afternoon and evening; egglaying and emergence often coincide Spring emergence everywhere except lasts through July 4 on Firehole, Madison in Park

Special thanks to John Juracek, Craig Mathews, and the late Gary LaFontaine for hatch info

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