Publications
Filter Total Items: 1978
Development of a 10-year limnological study of Crater Lake, Crater Lake National Park, Oregon, USA
This paper summarizes the development of a limnological study of Crater Lake conducted between 1983 and 1992. The program was mandated by Congress in the fall of 1982 after a panel of limnologists found the lake data base (1896–1981) to be inadequate to determine if the phytoplankton community had changed and if the lake was decreasing in clarity as suggested from independent studies between 1978
Authors
Gary L. Larson
Chemical solute mass balance of Crater Lake, Oregon
Crater Lake covers the floor of the caldera at the top of Mount Mazama. Surrounded by steep walls, the water surface of the lake occupies 78 percent of the catchment basin. No major rivers empty into the lake, and there is no surface outlet Based on a chemical solute mass balance model, mass inputs of major solute chemical components (Na, Ca, K, Mg, SO4, Cl, Si, and HCO3) from atmospheric depositi
Authors
Peter O. Nelson, J.F. Reilly, Gary L. Larson
Zooplankton assemblages in Crater Lake, Oregon, USA
The zooplankton community in Crater Lake was comprised of 11 rotifer species and 2 species of cladocerans. Most zooplankton taxa were distributed in winter and spring from the lake surface to a depth of about 200 m, the maximum depth of mixing of lake waters by wind energy. The distribution of zooplankton species was partitioned in the water column to a depth of 200 m during summer and fall, which
Authors
Gary L. Larson, C. D. McIntire, R.E. Truitt, M. W. Buktenica, E. Karnaugh-Thomas
Temperature, water chemistry, and optical properties of Crater Lake
Water temperature, water chemistry, and optical properties of Crater Lake were studied from 1983 to 1991. In winter and spring, wind energy and convection mixed the water column to a depth of 200 to 250 m. The lake was thermally stratified in summer and early fall; however, the epilimnion was only 5 to 20 m thick, and most of the 589 m deep water column was a cold hypolimnion. The lake was slightl
Authors
Gary L. Larson, C. D. McIntire, M. W. Buktenica
Microenvironments and microscale productivity of cyanobacterial desert crusts
We used microsensors to characterize physicochemical microenvironments and photosynthesis occurring immediately after water saturation in two desert soil crusts from southeastern Utah, which were formed by the cyanobacteria Microcoleus vaginatus Gomont, Nostoc spp., and Scytonema sp. The light fields within the crusts presented steep vertical gradients in magnitude and spectral composition. Near-s
Authors
F. Garcia-Pichel, Jayne Belnap
Crested wheatgrass-cheatgrass seedling competition in a mixed-density design
Plant competition experiments have historically used designs that are difficult to interpret due to confounding problems. Recently, designs based on a 'response function' approach have been proposed and tested in various plant mixture settings. For this study, 3 species were used that are important in current revegetation practices in the Intermountain West. 'Nordan' (Agropyron desertorum [Fish. e
Authors
Mark G. Francis, David A. Pyke
Characteristics of mineral licks used by white-tailed deer (Odocoileus virginianus)
Characteristics of mineral licks used by white-tailed deer (Odocoileus virginianus) were examined in the northern Black Hills of South Dakota in May 1992. Concentrations of sodium, nitrogen, phosphorus, potassium, calcium, chloride and magnesium, and soil texture, organic matter and pH for licks and nonlick soils were compared. Black Hills lick and nonlick samples also were compared to 67 other No
Authors
John F. Kennedy, Jonathan A. Jenks, Robert L. Jones, Kurt J. Jenkins
Survival and population size estimation in raptor studies: A comparison of two methods
ABSTRACT.--The Jolly-Seber model is a capture-recapture model that can provide less-biased survival and population size estimates than those produced from simple counting procedures. Parameter estimation by simple counts and Jolly-Seber methods are based on certain assumptions that directly determine the validity of estimates. Evuluation of assumptions for parameter estimation is a focus of this p
Authors
William R. Gould, Mark R. Fuller
Landscape characteristics of fragmented shrubsteppe habitats and breeding passerine birds
We examined the influence of local and landscape-level attributes of fragmented habitats in shrubsteppe habitats on the breeding distributions of Sage (Amphispiza belli) and Brewer's (Spizella breweri) Sparrows, Sage Thrashers (Oreoscoptes montanus), Horned Larks (Eremophila alpestris), and Western Meadowlarks (Sturnella neglecta) in the Snake River Plains of southwestern Idaho. We developed habit
Authors
Steven T. Knick, J.T. Rotenberry
Are red-tailed hawks and great horned owls diurnal-nocturnal dietary counterparts?
Red-tailed Hawks (Buteo jamaicensis) and Great Homed Owls (Bubo virginianus)are common in North America where they occupy a wide range of habitats, often sympatrically. The two species are similar in size and have been portrayed as ecological counterparts, eating the same prey by day and night. We tested the trophic similarity of the two species by comparing published dietary data from across the
Authors
C.D. Marti, Michael N. Kochert
Ecology and breeding biology of the Hawaii elepaio (Chasiempis sandwichensis bryani)
No abstract available.
Authors
Charles van Riper
A comparison of avian hematozoan epizootiology in two California coastal scrub communities
Passerine birds within two California (USA) coastal scrub ecosystems, an island and a mainland site, were examined for hematozoa from 1984 to 1990. Island birds had a significantly lower hematozoan prevalence than mainland birds. This prevalence difference can be related to a lack of appropriate hematozoan vectors on the island. Haemoproteus spp. and Leucocytozoon spp. were the most commonly encou
Authors
Paul E. Super, Charles van Riper