Lower Madison — Hatch Chart

Madison · Below Beartrap Canyon / Ennis Dam to Three Forks (confluence with Jefferson and Gallatin)

Mayfly Stonefly Caddis Midge Terrestrial | darker = peak activity

Insect Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Size

BWOs (Spring)

#16-20

BWOs (Fall)

#16-20

PMDs

#14-20

Tricos

#18-22

Salmonflies

#4-8

Golden Stones

#6-8

Caddis

#12-20

October Caddis

#8-10

Midges

#22-26

Hoppers

#8-14

Ants

#14-18

Beetles

#14-18

Mayflies

BWOs (Spring) May–Jun · #16-20

BWOs (Fall) Sep–Nov · #16-20

PMDs Jun–Aug · #14-20

Tricos Aug–Sep · #18-22

Stoneflies

Salmonflies Jul–Jul · #4-8

Golden Stones Jul–Jul · #6-8

Caddis

Caddis Jun–Aug · #12-20

October Caddis Sep–Oct · #8-10

Midges

Midges Nov–Mar · #22-26

Terrestrials

Hoppers Jul–Sep · #8-14

Ants Jul–Sep · #14-18

Beetles Jul–Sep · #14-18