Source: Conversations with Norman Anderson, OSU Professor Emeritus of Entomology (andersn@bcc.orst.edu, 541 737 5494)

Date: Spring 2002

Norm Anderson and his students carried out many aquatic entomology studies from the mid-1960's to 1995 in Oak Creek and in Berry Creek, another stream in the McDonald-Dunn Forest, Soap Creek Drainage (near Adair Village). Two classes used Oak Creek for class exercises. The Aquatic Entomology class collected specimens in Oak Creek but tended to focus on identification skills rather than field studies. The Ecological Methods class had a field component that studied a single site on Oak Creek annually for about 30 years (1965-1995). This course was co-taught by Peter McEvoy and Norm Anderson. The site was located about 500 meters above the West Fork of Oak Creek, within McDonald-Dunn Forest. Norm suggests that Peter may have student papers from the class.

Norm made the following comments about changes at the West Fork study site:

"Major changes that have occurred during the study interval are the increase in beaver activity, and the spread of the introduced grass, false brome (Brachypodium sylvaticum). Beavers have extensively modified the riparian area both by building dams and by felling trees; where ponds have filled with sediment or dams have failed plant succession has been reset to the earliest stages of colonization. Brachypodium has become the dominant vegtation not only in the meadow upslope from Oak Creek, but as the understory in the riparian area and in the upland conifer stand."

Another focus of Norm and his student Martin Dieterich was on summer-dry headwater streams. Norm says that one quarter of Oak Creek's aquatic insect biodiversity is in these small headwater streams that go dry annually. These are unpredictable habitats and the organisms are adapted for dispersal. Norm and Martin tried to revisit some study sites about five years after their initial work but the sites were already difficult to locate.

Norm made the following comments about a related on-going study:

"In a companion study for the last ten years, Norm has collected from three temporary streams in his backyard on the Witham Branch of Oak Creek. This work is mostly unpublished as species-level identifications are still required for much of the fauna. (Hopefully, future students will be involved in these biodiversity studies). In this remnant patch of Oak savanna we know of at least two undescribed species of aquatic insects and expect that there are several other new species."

Back to top

Datasets and Class Projects

Ecological Methods (1963-1995), Instructors Peter McEvoy and Norman Anderson, Department of Enotomology

See above for details.

FW456/556 Limnology and FW580 Stream Ecology

Since the 1980's the limnology class has studied the stream and carried out group project on water quality, limnology, fisheries, and entomology. Reports generally make comparisons between three stream reaches : forested, agricultural, and urban. These reports were archived by Kathy Staley's students (OSU Fisheries and Wildlife Department) in the 1990's and are available in the Fisheries and Wildlife Library (Nash Hall, Room #104). There is no digital index of these reports at this time but they are sorted into binders by topic.

Back to top

Available: OSU Valley Library LD4330 1969D .A9

Ball, E. E., 1946, The seasonal succession of stoneflies (Plecoptera) on Willamette valley trout streams [MS Thesis]: Department of Entomology, Oregon State College, 54 leaves, bound p.

Available: OSU Valley Library LD4330 1946 2

Notes: Kerst, 1970 compared the results of this study with new sampling. Norm Anderson commented that it would be great to do another study and have a 30 and 60 year comparison.

Dieterich, M., 1992, Insect community composition and physico-chemical processes in summer-dry streams of Western Oregon [Doctoral Dissertation]: Department of Entomology, Oregon State University, 191 p.

Available: OSU Valley Library LD4330 1993D .D54

Abstract: Seven streams, one of them permanent, were studied in western Oregon, USA. The research was designed to assess the value of summer-dry headwaters for conservation oriented landscape management. Streams were categorized primarily according to exposure (forest versus meadow sites) and secondarily according to flow duration (ephemeral = short-flow versus temporary = long-flow sites). Ephemeral streams have discontinuous flow and last less than three months annually. Temporary streams have continuous flow for more than five months each season.

Ephemeral forest streams were highly efficient at filtering road-generated sediment. Uptake lengths for suspended sediment were short (36 m-105 m) at moderately elevated input concentrations. As a result of the filtration mechanism, filtration efficiency is expected to increase as annual flow duration decreases.

Injection experiments yielded nitrate uptake rates of almost 1% per m of temporary stream channel. Exchange with subsurface flow was the most important route for nitrate removal from the water column. Biological uptake was insignificant in a light-limited forest stream, whereas a considerable amount of nitrate was retained by the biota in a nutrient-limited meadow channel.

At least 207 insect species were collected from the summer-dry streams. Species richness recorded from temporary forest streams exceeded that in an adjacent permanent headwater and there was high overlap between the fauna of the permanent and the temporary streams. Species richness in ephemeral channels was only 1/4 to 1/3 of that in long-flow forest streams.

Multivariate analysis of community structure revealed flow duration and microhabitat pattern (riffle - pool) as the most important environmental factors determining faunal composition in temporary forest streams. Summer drought conditions at the sample sites also were important.

By providing habitat and contributing to water quality in permanent downstream reaches, summer-dry streams have the potential to serve multiple purposes in conservation management. Their value from a conservation perspective is unexpectedly high. Landscape management therefore should be directed toward the preservation and protection of ephemeral and temporary streams.

Furnish, J. L., 1989, Factors Affecting the Growth Production and Distribution of the Stream Snail Juga silicula (Gould) [Doctoral Dissertation]: Department of Entomology, Oregon State University, 216 p.

Available: OSU Valley Library LD4330 1990D .F87

Abstract: The abundant stream snail, Juga silicula, was studied for four years in Oak Creek, a stream draining the eastern foothills of the Coast Range, Benton County, Oregon. A series of field and experimental investigations were conducted to examine how physical and biotic variables interact to determine the snail's growth and abundance. Temperature, population density, and food quantity and quality were of primary importance in determining snail growth rates and activity. Growth rates were depressed by cool water temperatures in the winter, by a high population density, and poor food quality. Positive growth on a variety of foods was observed, however highest growth was achieved on periphyton. Snail abundance was highest at current velocities <30 cm/sec, on coarse substrates and in unshaded patches. Snails of different sizes and ages were also segregated according to these physical variables. When the biomass of J. silicula was reduced by a factor of six, from a normal density of 13.3 to 2.1 grams per square meter, the production:biomass ratio was higher by a factor of about five in the low-density population (0.566 vs. 0.115). Production for the population maintained at high density was 1529 milligrams per square meter per yr compared to 1188 milligrams per square meter per yr for the low density population. These results provide strong evidence that snail growth may be limited through intraspecific, exploitative competition for food. Dispersal was stimulated by warm water temperature, high population density and food limitation. The knowledge gained from these studies of the seasonal abundance and distribution of J. silicula was also used to interpret patterns of distribution for benthic insects and to predict when snails are expected to have a significant impact on food resources and community structure. The snail exerts an impact on stream communities by exploitative competition through its ability to depress the available foods of both autochthonous and allochthonous origin. Its grazing activity results in interference competition, that mainly disturbs sedentary species. Grazing by J. silicula significantly reduced standing crop of chlorophyll a during 7 out of 12 months, and shredding by snails almost doubled the rate of weight loss of alder leaf packs. These studies illustrate how a single, abundant species responds to variation in the physical environment, as well as how it exerts a pervasive influence on the availability of food resources, habitat patches and stream community structure.

Kerst, C. D., 1970, The Seasonal Occurance and Distribution of Stoneflies (Plecoptera) of a Western Oregon Stream [MS Thesis thesis]: Department of Entomology, Oregon State University, 80 p.

Available: OSU Valley Library LD4330 1970 .K47

Abstract: Plecoptera were collected from four sampling stations selected to represent a range of conditions on Oak Creek, a small woodland stream originating in the foothills of the Oregon Coast Range. The elevation of Site I was 700 ft while the lowest site was located at 225 ft. Monthly benthos samples were taken for one year from a riffle and glide section at each site using a stovepipe sampler (6 in. dia.) and a standard tropical fish net. Samples were sorted in the laboratory and Plecoptera identified and placed into 1 mm size classes. Emergence of adults was measured for 13 months using a tent-shaped trap (1 m2) at each site. Traps were checked once or twice weekly.
Forty-two species of Plecoptera were found in Oak Creek. The number of species is very large when compared with other studies. The stonefly fauna is fairly similar to that reported 35 years ago.
Thirty-seven of the 42 species complete emergence during the spring. Temporal separation is marked in the emergence periods of Nemoura and Leuctra. Examples of split emergence periods and early emergence of males were found. Life cycle information is given for a number of species and genera.
Using the Shannon-Wiener function, diversity of emerging adults ranks by season as: Spring > Summer > Winter > Fall. The diversity of the sites on a yearly basis is: II > I > III > IV. Using a percentage of similarity index it is concluded that Sites I and II are very similar. Site III is intermediate while Site IV is quite different.
A number of examples of restricted distributions are cited. These examples illustrate that differences in longitudinal distribution are important in ecological segregation. Herbivorous stoneflies (sub-order Filipalpia) comprise a greater proportion of the fauna at the upper site while predaceous stoneflies (Setipalpia) predominate in the lower areas.
Water depth and amounts of leaves and silt are important factors in determining the distribution of stoneflies. Most species are abundant in leaf drifts. Microhabitat selection does not appear to be rigorous.

Lehmkuhl, D. M., 1969, Biology and downstream drift of some Oregon Ephemeroptera [Doctoral Dissertation]: Department of Entomology, Oregon State University, 110 leaves, bound : p.

Available: OSU Valley Library LD4330 1969D .L44

Muller, H., 1990, The role of sediment abrasion in leaf decomposition processes: A comparison of leaf degradation rates due to mechanica and biological processing in temporary streams: Diplomarbeit am Institut fur Physische Geographie/Hydrologie, Albert-Ludgwigs-Universitat Freiburg, Germany.

Notes: Norm Anderson was the research supervisor

Reed, T. L., 1995, Drift, wood, and grazing cattle : macroinvertebrates in managed streams [M.S. Thesis]: Department of Entomology, Oregon State University, 107 p.

Available: OSU Valley Library LD4330 1978 .P37

Speir, J. A., 1969, Biological and ecological aspects of the black flies of the Marys River drainage system (Diptera: simuliidae) [MS Thesis]: Department of Entomology, Oregon State University, 80 leaves, bound : p.

Available: OSU Valley Library LD4330 1969 .S66

Speir, J. A., 1975, The ecology and production dynamics of four black fly species (Diptera:simuliidae) in western Oregon streams [Doctoral Dissertation]: Department of Entomology, Oregon State University, [17], 297 leaves, bound : p.

Available: OSU Valley Library LD4330 1976D .S68

Wold, J. L., 1973, Systematics of the genus Rhyacophila (Trichoptera:Rhyacophilidae) in western North America with special reference to the immature stages [MS Thesis]: Department of Entomology, Oregon State University, [10], 229 leaves, bound : p.

Available: OSU Valley Library LD4330 1974 .W64

Back to top

Anderson, N. H., 1997, Phenology of Trichoptera in summer-dry headwater streams in western Oregon, USA, in Holzenthal, R.W. and Flint, O.S. Jr (eds) The 8th International Symposium on Trichoptera: Ohio Biological Survey, p. 7-13.

Abstract: Studies of the temporary-stream fauna in western Oregon were expanded by establishing permanent plots in 1992 in two streams draining an oak savanna near Corvallis, Oregon. Drought conditions in 1993-1994 interrupted larval development in the short-flow channel (Outgate Beck) which dried completely. Seeps and hyporheic flow in Oak Burn enabled the caddis community to persist despite a decreased flow period. About 17 species of Trichoptera were recorded from benthos collections and emergence traps. The odontocerid Nerophilus californicus (Hagen) and the hydropsychid Parapsyche almota Ross were two of the relatively common species in the oak savanna streams that were not recorded in our earlier lists from temporary headwaters of forested streams.

Anderson, N. H., and Bourne, J. R., 1974, Bionomics of three species of glossosomatid caddis flies (Trichoptera: Glossomatidae) in Oregon: Canadian Journal of Zoology, v. 52, p. 405-411.

Abstract: The life cycles of three species of caddis flies of the family Glossosomatidae, Anagapetus bernea Ross, Agapetus bifidus Denning, and Glossosoma penitum Banks, are compared based on monthly collections from Oak Creek and Berry Creek, Benton County, Oregon. Glossosoma penitum, the most abundant species, is bivoltine with overlapping summer and winter generations. Anagapetus bernea and A. bifidus is more common in the slower water of glides, whears G. penitum and A. bernea occur chiefly on the riffles. Anagapetus bernea is more restricted to the headwater regions and small side branches than is G. pentium.

Anderson, N. H., and Dieterich, M., 1993, The Trichoptera fauna of temporary headwater streams in Wester Oregon, USA, in Otto, C., ed., Proceeding of the 7th International Symposium on Trichoptera, 1992: Leiden, Backhuys Publishers, p. 233-237.

Anderson, N. H., and Hansen, B. P., 1987, An annotated check list of aquatic insects collected at Berry Creek, Benton County, Oregon 1960-1984: Systematic Entomology Laboratory, Department of Entomology, Oregon State University, Occasional Publication Number 2.

Abstract: This report summarized collection records of aquatic insects from Berry Creek for over 25 years. General collecting and about 20 research projects have resulted in a list of over 325 taxa for the site. Eight orders and 63 families are represented; almost one third of the species are Chironomidae.
Berry Creek is a second-order woodland stream of low gradient in the eastern foothills of the Oregon Coast Range (altitude 120 m). The stream is underlain by basaltic rocks with some sandstone and siltstone. The water is cool (<20 degrees C), low in calcium carbonate and nitrates, and has a pH range of 7.1-7.8.
The check list is based primarily on collections from a reach with flow (0.003-0.015 cubic meters per second) controlled by a dam and bypass canal constructed in 1958. Excluding records of species collected only in an intermittent tributary (about 20 species) and also excluding Trichoptera from black lights (16 species), considered transients rather than a local population, reduced the current taxa list for Berry Creek to slightly under 300 species.

Notes: Berry Creek is another small steam within the McDonald-Dunn forest. It is within the Soap Creek Drainage.

Anderson, N. H., and Lehmkuhl, D. M., 1968, Catastrophic drift of insects in a woodland stream: Ecology, v. 49, p. 198-206.

Abstract: The effect of early fall rains on the downstream drift or displacement of insects was studied for two seasons by collecting the entire streamflow at one point through a drift net. Drift rate increased within 24 hr after the start of each rainy period, with the increase approximately proportional to the increase in stream flow. Freshets due to less than 1 inch (2.5 cm) of rain caused a fourfold increase in numbers and fivefold to eightfold increase in biomass. Major components of the drift were Ephemeroptera, Plecoptera, Diptera and terrestrial insects.

Plecoptera and Ephemerotpera retained the day-night periodicity of behavioral drift during freshets, but drift of Chironomidae (Diptera) was attributed to catastrophic and constant drift. Mean weight per individual of several taxa was greater at night than day, in freshet than nonfreshet periods, and in drift compared with benthos samples.

Though catastrophic drift due to fall freshets displaced large numbers of individuals, the standing crop of the benthos increased during the fall because of hatching. The drift may be beneficial in dispersing aggregations of young larvae. Removal of allochthonous food by increased water flow could be more detrimental to benthos populations than the direct mortality caused by catastrophic drift.

Anderson, N. H., and Wold, J. L., 1972, Emergence trap collections of Trichoptera from an Oregon stream: Canadian Entomology, v. 104, p. 189-201.

Abstract: Adult Trichoptera of 39 species representing 11 families were collected from four emergence traps in Oak Creek, Corvallis, Oregon, between May 1968 and December 1970. Glossosomatidae and Limnephilidae were the most abundant families, but Rhyacophilidae was represented by the most species. Relative abundance, season occurrence, sex ratio, and ecological segreation of related species are discussed.

Azam, K. M., and Anderson, N. H., 1969, Life history and habits of Sialis rotunda and S. californica in Western Oregon: Annals of the Entomological Society of America, v. 62, no. 3, p. 549-558.

Abstract: Comparative ecological studies of Sialis rotunda Banks and S. californica Banks (Megaloptera: Sialidae) were made in western Oregon from 1966 to 1968. Techniques were developed for rearing both species, and the duration of the life cycles was determined in aquaria, in a laboratory stream, and in the natural habitats. It was found by rearing individual larvae that there are 10 larval instars, and measurements were recorded of body length and head width of all stadia. The duration of each of the life stages was determined.

Dieterich, M., and Anderson, N. H., 1995, Life cycles and food habitats of mayflies and stoneflies from temporary streams in Western Oregon: Freshwater Biology, v. 34, p. 47-60.

Dieterich, M., and Anderson, N. H., 1998, Dynamics of abiotic parameters, solute removal and sediment retention in summer-dry headwater streams of Western Oregon: Hydrobiologia, v. 379, p. 1-15.

Dieterich, M., and Anderson, N. H., 2000, The invertebrate fauna of summer dry streams in Western Oregon: Archiv fur Hydrobiologie, v. 147, no. 3, p. 273-295.

Available: OSU Valley Library OSU Valley Library QH301 .A77

Dieterich, M., Anderson, N. H., and Anderson, T. M., 1997, Shredder-collector interactions in temporary streams of Western Oregon: Freshwater Biology, v. 38, no. 2, p. 387-393.

Hawkins, C. P., and Furnish, J. L., 1987, Are snails important competitors in stream ecosystems?: Oikos, v. 49, p. 209-220.

Kerst, C. D., and Anderson, N. H., 1974, Emergence patterns of Plecoptera in a stream in Oregon, USA.: Freshwater Biology, v. 4, no. 3, p. 205-212.

Kerst, C. D., and Anderson, N. H., 1975, The Plecoptera community of a small stream in Oregon, U.S.A.: Freshwater Biology, v. 5, no. 2, p. 189-203.

Lehmkuhl, D. M., and Anderson, N. H., 1970, Observations on the biology of Cinygmula reticulata McDunnough in Oregon: The Pan-Pacific Entomologist, v. 46, no. 4, p. 268-274.

Lehmkuhl, D. M., and Anderson, N. H., 1972, Microdistribution and density as factors affecting the downstream drift of mayflies: Ecology, v. 53, p. 661-667.

Abstract: During high volume of flow in a stream that has considerable seasonal fluctuation, the microdistribution of five species of mayflies was determined by displacement of individual by drift from rapid current areas to those with gentle or no current. The major effect of drift was dispersal, not depletion, of the mayfly population. Occurrence in drift is determined by a species-specific complex of interdependent factors including life cycle, micro-distribution (both before and after the effect of spates), and the behavioral characteristic of individual species.

Home | About | Maps | Research | Management | Search