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DigitalCommons@USU
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This review summarizes the state of knowledge regarding herbivory in stream ecosystems by quantitatively analyzing the results of 89 experimental studies published between 1972 and 1993. Our primary objective was to determine if general patterns...
1995-01-01
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We examined how condition (weight at length) of rainbow trout Oncorhynchus mykiss varied in relation to availability of drifting invertebrates and temperature at two locations over four seasons in the Green River, Utah. Food availability (daytime...
1995-01-01
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Tadpoles of the tailed frog (Ascaphus truei) are common in riffles within many small, high-gradient streams of the Pacific Northwest (United States and southern Canada), where they typically graze periphyton from exposed cobbles. We conducted...
1994-01-01
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We propose a hierarchical system of classifying stream habitats based on three increasingly fine descriptions of the morphological and hydraulic properties of channel geomorphic units. We define channel geomorphic units as areas of relatively...
1993-01-01
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1. In four separate field experiments near Mount St Helens (Washington, U.S.A.) during 1986, the grazing effects of two large benthic herbivores, tadpoles of the tailed frog Ascaphus truei and larvae of the caddisfly Dicosmoecus gilvipes, were...
1992-01-01
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To test the hypothesis that a general relationship exists between morphology and developmental temperature, we quantified morphological variation in six species of aquatic insects. We examined three holometabolous species (Trichoptera:...
1991-01-01
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Streams normallv consist of mosaics of habitat patches (Pringlc et al. I9BB). each of l,hich provides cronditions and rcsourccs suitable for different Ipes of lliola. We t1''picalh intlude rilfles. pools. and runs as stream habitais. but these...
1991-01-01
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The role of woody debris in nutrient cycling was investigated in two catastrophically disturbed streams in the Pacific Northwest that had been subjected to large inputs of wood. One study site in each catchment had all woody debris removed (take...
1990-01-01
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Habitats or environmental factors that convey spatial and temporal resistance and/or resilience to biotic communities that have been impacted by biophysical disturbances may be called refugia. Most refugia in rivers are characterized by extensive...
1990-01-01
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Root (161) defined a guild as "a group of species that exploit the same class of environmental resources in a similar way." With this intuitively appealing, seductively simple definition, he commenced the development of what has become a Gordian...
1989-01-01
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Current theory in stream ecology posits a strong linkage between watershed or riparian vegetation and structure of consumer communities in streams (Cummins et al. 1984, Minshall et al. 1985, Vannote et al. 1980). In this view, degree of vegetative...
1988-01-01
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Streams near Mt. St. Helens, Washington, differ in degree of watershed disturbance caused by the 1980 eruption. Summer densities of tailed frog tadpoles (Ascaphus truei) varied considerably both within and between several of these streams....
1988-01-01
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The major objectives of this paper are to summarize and synthesize what we know about the energetics of lotic systems, to identify some of the major gaps in our knowledge, and in so doing to provide guidance for new research directions. We...
1988-01-01
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Juga silicula (Gould) is an omnivorous pleurocerid snail that inhabits many streams in NW USA. In some streams it comprises over 90% of invertebrate standing crop bio-mass. Analysis of benthic samples from 20 stream reaches showed that densities...
1987-01-01
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1. Macroinvertebrate abundance and production were compared between an open and shaded site of a stream in the Wasatch Mountains, Utah. Mean biomass was significantly higher at the open site for midges (Chironomidae), 4.6x; Baetis bicaudatus,...
1986-01-01
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Data on food habits were obtained for 20 species in the mayfly family Ephemerellidae. Diet of a species often varied with site, habitat and size, but such variation did not completely mask differences among species. Adaptive radiation in diet is...
1985-01-01
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The imagines of Ephemerella verruca Allen and Edmunds are described and the taxonomic relation of males to other species of the genus is discussed. Brief notes on the species' natural history are included.
1984-01-01
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Substrate associations and longitudinal distributions are described for 12 species of Ephemerellidae. Habitat specialization seems to have been a major means of adaptive radiation within this family. All species showed restrictive use of available...
1984-01-01
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Relationships between density of fish and salamanders, riparian canopy, and physical habitat were investigated by studying 10 pairs of streams. Among vertebrate taxa, salmonids and sculpins were more abundant in streams without riparian shading...
1983-01-01
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The relative importance of surrounding riparian vegetation and substrate composition on invertebrate community structure was investigated in six streams in Oregon, USA. We found that canopy type was more important than substrate character in...
1982-01-01
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The relative importance of surrounding riparian vegetation and substrate composition on invertebrate community structure was investigated in six streams in Oregon, USA. We found that canopy type was more important than substrate character in...
1981-01-01
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Fish are important components of the Mount St. Helens aquatic system. Historically, no other region of Washington State supported as many native freshwater and anadromous species (anadromous fish mature in the ocean but spawn in freshwater) as did...
2005-01-01
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