Home » Entomology » Sowbug


Scientific Name: genus Isopoda

Common Names:Sowbug, aquatic sowbug


Click thumbnail for enlarged version


SIZE: 10-18 mm (3/8 to 11/16 in)

COLOR: Back: Gray, pink-gray, black, brown. Belly a lighter color.

OTHER CHARACTERISTICS: Flattened appearance. Seven pairs of legs.


About Sowbugs

Every fly angler knows or soon learns about scuds, yet in some rivers sowbugs are a much bigger food source than scuds.

One reason sowbugs dwell in figurative obscurity is because they dwell in literal gravel. Anglers don't often see them, even when they are present. But where large populations occur, sowbugs are an important part of trout diets and are associated with deep-bellied fish.

They can flourish in slow, unpolluted tailwaters, springs, creeks, and small ponds, where they feed on weeds and leafy debris. Sowbugs often--but not always--occupy the same habitat as scuds. Populations tend to be spotty: a lot in one place, but very few in another.

Imititations are usually fished with trout indicator or tight line tactics in slow runs of weedy streams. Where they occur, they can be available all year.

Articles About Sowbugs

Click headline to read entire article

Aquatic Sowbugs Aquatic sowbugs thrive in many tailwaters, and trout grow fat on them. So why are most Western fly anglers unaware of their existence? Jeff Morgan


Sowbug. (photo © 2006 Arlen Thomason. Used by permission.)

Matching Sowbugs







Egg Fly

6-10/Pink, peach, white, purple, many others

Indicator, Tight line


Select Another

Use the pull-down menus below to select one mayfly, caddis, stonefly, or other trout food.



Disclaimer | About Westfly | Contact | Privacy Notice | © Copyright Notice | Daily Email

Click here to learn about advertising

Home Forums Fishing Reports River Levels Tides Fly Patterns Entomology Articles Legacy