Pteronarcys californica (Salmonfly) of Gunnison County, Colorado

Plecoptera: Pteronarcyidae

Pteronarcys californica
Salmonfly, Giant Salmonfly, Willowfly, Giant Stonefly

Newport 1848

Updated 15 Jan 2010
TSN 102473

Habitat

Nymphs are found in medium sized rivers, usually in trash piles and leaf packs or under large stones in eddies near shore.

Life History

Richardson and Gaufin noted this species ate detritus. All of the specimens they examined had sand in their guts. No sand was found in the hind gut so they assume the nymphs regurgitate the sand as required. Algae was found in many specimens. Traces of animal matter were found in some guts. Laboratory observations of feeding habits on leaf packs led to the observation that P. californica is occasionally cannibalistic. Usually nymphs lie hidden with antennae protruding and waving side to side. When food contacts their antennae the nymphs rush out and sieze the food with their maxillae. While searching for food, P. californica nymphs move slowly with their antennae continuously moving back and forth.

Locations Collected

Gunnison River at Soap Creek and McCabe Lane, Black Canyon, Lake Fork of the Gunnison.

References

Colburn,T 1986 The use of the stonefly Pteronarcys californica Newport as a measure of biologically available cadmium in a high altitude river system Colorado, USA. Water Quality Bulletin 11, 141-147.
Concerned about the heavy metal Cadmium in water often used for human consumption in Gunnison County, Colorado, the author exposed P. californica in cages to the water and accompanying sediments in various rivers in the upper Gunnison Basin. She found Cadmium concentrations lowest in the highest elevation cages. An interesting result was that sometimes the stoneflies had higher concentrations of Cadmium that the water samples might indicate. She said this showed that stoneflies indicate the cadmium present in the sediments. She suggests P. californica metal concentrations may be a better way to monitor stream levels of Cadmium than water samples.

Gregory,J.S., Beesley,S.S. and Van Kirk,R.W. 2000 Effect of springtime water temperature on the time of emergence and size of Pteronarcys californica in the Henry's Fork catchment, Idaho, U.S.A. Freshwater Biology 45(1) 75 Abstract

Hornig,CE and Brusven,MA 1986 Effects of suspended sediment on leaf processing by Hesperophylax occidentalis (Trichoptera: Limnephilidae) and Pteronarcys californica (Plecoptera: Pteronarcidae). Western North American Naturalist 46 (1)
Abstract: "The effects of suspended sediments on stream invertebrate detrital processing were investigated under replicated conditions in light and temperature-controlled chambers in the laboratory. The leaf-shredding insects Pteronarcys californica and Hesperophylax occidentalis were studied. Mean daily ingestion rates were lower among insects subjected to suspended sediments (1.5 and 3.0 g/l) than insects held in suspended sediment-free environments for seven of the eight trials. In five of the eight trials, mean ingestion rates were suppressed by ?41% when compared to insects held in suspended sediment-free environments. Feeding inhibition was typically greater at the end of the feeding trials (14 days) than at the beginning (0–4 days). The effects of suspended sediments on ingestion were apparently related to the feeding status of the insects at the time of a trial. Insects in an active feeding mode were less influenced by suspended sediment than those in an inactive feeding mode. We conclude that, depending on the season and the duration of impact, suspended sediment can suppress processing of coarse particulate organic matter and thus adversely influence important nutrient and energy pathways in low-order streams. "

Illinois Natural History Survey (INHS) accessed 15 Jan 2010 http://www.inhs.uiuc.edu/

Cat. #	Species	Stream	Location	County	State	Country	Date
5805	Pteronarcys californica	Gunnison River	Gunnison	[Gunnison]	Colorado	United States of America	7 June 1954
5806	Pteronarcys californica	Gunnison River	Gunnison	[Gunnison]	Colorado	United States of America	7 June 1954
5807	Pteronarcys californica	Gunnison River	Gunnison	[Gunnison]	Colorado	United States of America	7 June 1954

Needham,JG; Claassen,PW 1925 A Monograph of the Plecoptera of North America. Entomological Society of America, Lafayette, Indiana. 397 pages.

Nehring,RB 1976 Aquatic insects as biological monitors of heavy metal pollution. Bulletin of Environmental Contamination and Toxicology 15 2, 147-154.
The author established TL50s of 10.1 - 13.9 mg/l for Copper, greater than 19.2 mg/l for Lead, .004 -.009 mg/l for Silver and greater than 13.9 for Zinc. A TL 50 is the median lethal concentration at which half the population dies. This is a standard laboratory toxicity test used for chemicals (among other things). [Yikes, these are such handsome animals, this would be a difficult experiment to do.] Nehring also measured bioaccumulation of the metals. Clean Pteronarcys that were placed in artifical streams with various amounts of metals concentrated those metals 100 times and more over background levels. The author suggests using bioaccumulation in these animals or others to estimate small amounts of metals in water. Analysis of metals in aquatic insects may help figure out what happened if collected shortly after a fish kill.

Newport,G 1848 On the anatomy and affinities of Pteronarcys regalis Newman; with a postscript containing descriptions of some American Perlidae, together with notes on their habits. Transactions Linnean Society of London 20: 425-452.

Richardson,JW; Gaufin,AR 1971 Food habits of some western stonefly nymphs. Transactions of American Entomological Society 97, 91-121.
     They examined the guts of 275 nymphs from the Provo River in Utah and the Gunnison River in Colorado. Thier results were that on average, P. californica guts contained 79.7% detritus. 99.6% of the animals they looked at had sand particles in their guts as well. Filamentous green algae was 6.6% of the diet while diatoms were only 2.1 percent. Traces of animal material were found in 149 of the 275 nymphs. Baetidae and Ephemerella sp. were the most common mayflies found in the guts.

Ruesink,JL and Srivastava,DS 2001 Numerical and per capita responses to species loss: mechanisms maintaining ecosystem function in a community of stream insect detritivores. Oikos (93) 2: 221-234. Abstract Sanders,HO and Cope,OB 1968 The relative toxicities of several pesticides to naiads of three species of stoneflies. Limnology and Oceanography 13(1) 112-117. First page

Schultheis,AS; Booth,JY; Vinson,MR; Miller,MP 2008 Genetic evidence for cohort splitting in the merovoltine stonefly Pteronarcys californica (Newport) in Blacksmith Fork, Utah. Aquatic Insects: International Journal of Freshwater Entomology, 1744-4152, 30(3) 187 – 195.

Sutton, M.Q. 1985. The California salmon fly as a food source in northeastern California. J. Calif. & Great Basin Anthropol. 7(2): 176-182.
     The Modoc, Wintu, Achumawi and Atsugewi Indians along the Pit River and other rivers in Northeastern California ate lots of salmonflies. References within this paper said the Wintu people collected adults in the morning and then boiled them to eat now or dried them for later use. The Atsugewi people also collected Salmonflies in the morning and removed their wings before boiling the bodies.

Townsend,GD; Pritchard,G 2000 Egg development in the stonefly Pteronarcys californica Newport (Plecoptera: Pteronarcyidae) Aquatic Insects: International Journal of Freshwater Entomology, 1744-4152, V22(1)19 – 26.

Ward,JV; Kondratieff,BC; Zuellig,RE 2002 An Illustrated Guide to the Mountain Stream Insects of Colorado. 2nd ed. University Press of Colorado, Boulder, Colorado. 219 pages.
     Illustration of P. californica nymph on page 66, figure 26. This figure is reproduced on the website: http://waterknowledge.colostate.edu/pteronar.htm.

Brown, Wendy S. 2004 Plecoptera or Stoneflies of Gunnison County, Colorado
www.gunnisoninsects.org