Old Rupe is "off his feet" for a while, and we will fill in
for him the best we can. If you are knowledgeable about a particular
insect or local hatch, please help us out - contact:
Don't worry about photos, we have good references.
Stoneflies are the creepiest crawlers of the trout world. Well suited for some horror movie on
Stonezilla Engulfs the World! They really are members of the order Plecoptera
but their common name of Stoneflies probably came from where they are found along streams
hiding or crawling in the rocks and stones. They are closely related to cockroaches, indeed very
The lavae is well matched by the Montana Nymph.
Tie them to match, size and color, whatever stones are in your region at various
times of the year. This is an important fly.
Adult stone flies have four wings, which are heavily veined. The wings lie
flat over the back, except when they fly. Auto accidents have been caused
on blacktop highways caused by misguided Stone Flies. They mistake the
blacktop for water and land in such numbers as to make the road slippery.
Most of the stoneflies are restricted to highly oxygenated waters, and are considered
an indicator of the water quality. These are freshwater insects, with around 500 known
North American species, ranging in size from very small to the giant stones like the
Salmonfly. While rivers are the most likely home to salmonflies, some lakes, especially
those with wave action, like Lake Tahoe, have large populations.
Stoneflies are very important food sources for game fishes, and some even emerge in winter.
All stoneflies are fish food in the larvael stage as well. In fact, the first recorded artificial
fly - made over four hundred and fifty years ago - was based on a British stonefly.
The governing factors for emergence of stones is water temperature, altitude and latitude.
The larvae climbs out of the water onto streamside rocks and bushes or structure of some
sort, and then once their wings are dried, fly over the water to deposit their eggs. Some dip
onto the water surface, and other adults crawl back into the water from whence they came.
The males sometimes emerge before the females, and the males of some species actually attract
females by beating their abdomen against a hard surface. A responsive female will return
Stoneflies unlike the mayfly, live as adults from a few days to about five weeks! The emergence
usually starts at the higher altitudes of a stream and continues downstream as the correct
conditions occur. Fishermen get a really great shot at this hatch!
Another favorite of fishermen because it is an early Western
spring hatch, March in some places, is the Gray Stone (called the Nasqually
or Squalla in some regions). Other 'stones' vary in color from the salmon
pink to tan and dark brown.
Knowledgeable fly fishers on rivers like the Madison and Yellowstone in Montana fish the
giant stonefly Pteronarcyidae 'hatch' from it's beginnings to the end downstream,
and may have a couple of weeks of excellent fishing with the size 2 Salmonfly.
Some of the other well-known stonefly patterns include the Golden Stone (also one of the 'giants'),
Yellow Sally (size 12 - 16), Sofa Pillow, Bird's Stonefly, and Artesan Green. Both Woolly
Worms for the nymph, or Elk Hair Caddis tied dark in sizes 14 - 18 are excellent for the little
For the panfishers, Smallmouth Bass also eat stoneflies.
Emerged and egg laying stoneflies ride in the water, they don't float on top of
the water, as do mayflies and caddis. Keep this in mind as you tie or buy flies to imitate
The emergence of the adult stonefly falls into the minor miracle catagory, for a complete
photo history of it check out this Ladyfisher article.
Stoneflies, both the nymph and the adult are under fished in many regions simply because they
don't hatch as mayflies and caddis do, making a visible entry into the fisherman's world.
Check the waters edge for empty shucks and watch for the egg-laying! The fish love 'em
and you will too! ~ LadyFisher
For more on stoneflies check these out:
Photo credits: Stonefly nymph drawings from Aquatic Entomology by
W. Patrick McCafferty, published by Jones and Bartlett, remaining photos by James