Geology topics

T.M. Short

Publications and source records attributed to T.M. Short.

3 recordsLinked to original sources

USGS2006

Relation of fish communities to environmental conditions in urban streams of the Wasatch Front, Utah

Twenty-eight sites along the Wasatch Front, north central Utah, representing the range ot urban land use intensity for wadeable streams of the area, were sampled in September 2000. Fish communities were assessed by single-pass electrofishing, and physical habitat and water-quality characteristics were measured. On average, nonnative species comprised 54% of species richness and 53% of relative abundance, although only Salmo trutta and Pimephales promelas were very abundant at any 1 site. Salmo trutta and Catostomus platyrhynchus, a native species, were the most widely distributed and abundant species captured. Analysis of fish communities using nonmetric multidimensional scaling (NMDS) revealed a community gradient from sites dominated by Salmo trutta and Cottus species (C. bairdi, C. beldingi) to sites dominated by Catostomus platyrhynchus. Sites dominated by C. platyrhynchus were smaller in size and had less habitat cover, smaller average substrate size, higher concentrations of dissolved constituents, and higher water temperature than sites dominated by S. trutta. Sites dominated by C. platyrhynchus were located in more intensely urbanized watersheds at lower elevations. Stream size and associated instream habitat availability appear to limit S. trutta distribution and abundance, while native species appear more tolerant of decreased water quality and increased water temperatures in more urbanized streams. Most of the study sites are affected by development of water infrastructure for human water use (e.g., dams and diversions), and this infrastructure may play a role in dispersal of species.

Western North American Naturalist↗

USGS2003

Response of benthic invertebrate assemblages to metal exposure and bioaccumulation associated with hard-rock mining in northwestern streams, USA

Benthic macroinvertebrate assemblages, environmental variables, and associated mine density were evaluated during the summer of 2000 at 18 reference and test sites in the Coeur d'Alene and St. Regis River basins, northwestern USA as part of the US Geological Survey's National Water-Quality Assessment Program. Concentrations of Cd, Pb, and Zn in water and (or) streambed sediment at test sites in basins where production mine density was ???0.2 mines/km2 (in a 500-m stream buffer) were significantly higher than concentrations at reference sites. Zn and Pb were identified as the primary contaminants in water and streambed sediment, respectively. These metal concentrations often exceeded acute Ambient Water Quality Criteria for aquatic life and the National Oceanic and Atmospheric Administration Probable Effect Level for streambed sediment. Regression analysis identified significant correlations between production mine density in each basin and Zn concentrations in water and Pb in streambed sediment (r2 = 0.69 and 0.65, p < 0.01). Metal concentrations in caddisfly tissue, used to verify site-specific exposures of benthos, also were highest at sites downstream from intensive mining. Benthic invertebrate taxa richness and densities were lower at sites downstream than upstream of areas of intensive hard-rock mining and associated metal enrichment. Benthic invertebrate metrics that were most effective in discriminating changes in assemblage structure between reference and mining sites were total number of taxa, number of Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, and densities of total individuals, EPT individuals, and metal-sensitive Ephemeroptera individuals.

Journal of the North American Benthological Societ↗

USGS1997

Spatial heterogeneity of mercury bioaccumulation by walleye in Franklin D. Roosevelt Lake and the upper Columbia River, Washington

We examined mercury concentration in muscle of walleye Stizostedion vitreum from three reaches in Franklin D. Roosevelt Lake, a reservoir on the Columbia River, and from the upper Columbia River, an area contaminated by wastes from metal mining and associated processing activities. Our objectives were to describe the relation between size and age of walleyes and tissue concentrations of mercury and to compare mercury concentrations within a single reservoir system among spatially segregated cohorts. Overall, mercury concentrations in walleye muscle ranged from 0.11 to 0.44 mg/kg (wet weight) and were positively correlated with age, weight, and length of the fish. Mercury concentrations in walleyes varied spatially within the system; the highest concentrations were in fish from the lower and middle reaches of the reservoir. Condition factor of age-2+ fish was inversely related to tissue concentration of mercury and was lower in fish from the lower and middle reaches than in fish from the upper reach. Spatial patterns in condition factor and mercury in walleyes were unrelated to concentrations of total mercury in surficial bed sediments, which ranged from less than 0.05 to 2.8 mg/kg (dry weight). We suggest that the observed spatial differences in the concentrations of mercury in walleyes may be attributed to the fish preferring to spawn and forage in specific areas where the bioavailability of mercury varies due to local differences in the physical and chemical environment.

Transactions of the American Fisheries Society↗