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Representation of natural vegetation in protected areas: Capturing the geographic range
J. M. Scott, M. Murray, R.G. Wright, B. Csuti, P. Morgan, R.L. Pressey
2001, Biodiversity and Conservation (10) 1297-1301
Current conservation strategies for plant and animal species rarely address the need to protect the species throughout its geographic range thereby capturing potential genetic and ecological variation. We examined the degree that existing protected areas in the western United States satisfied this goal for four widespread vegetation cover types. We...
Magmatic gas scrubbing: Implications for volcano monitoring
R.B. Symonds, T.M. Gerlach, M.H. Reed
2001, Journal of Volcanology and Geothermal Research (108) 303-341
Despite the abundance of SO2(g) in magmatic gases, precursory increases in magmatic SO2(g) are not always observed prior to volcanic eruption, probably because many terrestrial volcanoes contain abundant groundwater or surface water that scrubs magmatic gases until a dry pathway to the atmosphere is established. To better understand scrubbing and...
Trends in long-period seismicity related to magmatic fluid compositions
M.M. Morrissey, B. A. Chouet
2001, Journal of Volcanology and Geothermal Research (108) 265-281
Sound speeds and densities are calculated for three different types of fluids: gas-gas mixture; ash-gas mixture; and bubbly liquid. These fluid properties are used to calculate the impedance contrast (Z) and crack stiffness (C) in the fluid-driven crack model (Chouet: J. Geophys. Res., 91 (1986) 13,967; 101 (1988) 4375; A...
Declining scaup populations: A retrospective analysis of long-term population and harvest survey data
A. D. Afton, M.G. Anderson
2001, Journal of Wildlife Management (65) 781-796
We examined long-term databases concerning population status of scaup (lesser [Aythya affinis] and greater scaup [A. marila] combined) and harvest statistics of lesser scaup to identify factors potentially limiting population growth. Specifically, we explored evidence for and against the general hypotheses that scaup populations have declined in association with declining...
Survey protocol for assessment of endangered freshwater mussels the Allegheny River, Pennsylvania
D. R. Smith, R.F. Villella, D. P. Lemarie
2001, Journal of North American Benthological Society (20) 118-132
The United States Endangered Species Act (ESA) requires a biological assessment of any activity that is authorized, funded, or carried out by a federal agency and likely to affect a federally listed endangered species or its critical habitat. We developed a standardized survey protocol for biological assessments of the effects...
Distribution of oxygen-18 and deuteriun in river waters across the United States
Carol Kendall, Tyler B. Coplen
2001, Hydrological Processes (15) 1363-1393
Reconstruction of continental palaeoclimate and palaeohydrology is currently hampered by limited information about isotopic patterns in the modern hydrologic cycle. To remedy this situation and to provide baseline data for other isotope hydrology studies, more than 4800, depth- and width-integrated, stream samples from 391 selected sites within the USGS...
Mapping crustal heterogeneity using Lg propagation efficiency throughout the Middle East, Mediterranean, Southern Europe and Northern Africa
D.E. McNamara, W.R. Walter
2001, Pure and Applied Geophysics (158) 1165-1188
In this paper we describe a technique for mapping the lateral variation of Lg characteristics such as Lg blockage, efficient Lg propagation, and regions of very high attenuation in the Middle East, North Africa, Europe and the Mediterranean regions. Lg is used in a variety of seismological applications from magnitude...
Mars Color Imager (MARCI) on the Mars Climate Orbiter
M. C. Malin, J.F. Bell III, W. Calvin, R.T. Clancy, R.M. Haberle, P.B. James, S.W. Lee, P.C. Thomas, M.A. Caplinger
2001, Journal of Geophysical Research E: Planets (106) 17651-17672
The Mars Color Imager, or MARCI, experiment on the Mars Climate Orbiter (MCO) consists of two cameras with unique optics and identical focal plane assemblies (FPAs), Data Acquisition System (DAS) electronics, and power supplies. Each camera is characterized by small physical size and mass (∼6×6×12 cm, including baffle; <500 g),...
Conservation status and recovery strategies for endemic Hawaiian birds
Paul C. Banko, Reginald E. David, James D. Jacobi, Winston E. Banko
2001, Studies in Avian Biology (22) 359-376
Populations of endemic Hawaiian birds declined catastrophically following the colonization of the islands by Polynesians and later cultures. Extinction is still occurring, and recovery programs are urgently needed to prevent the disappearance of many other species. Programs to recover the endemic avifauna incorporate a variety of conceptual and practical approaches...
Uncertainty, learning, and the optimal management of wildlife
B. Kenneth Williams
2001, Environmental and Ecological Statistics (8) 269-288
Wildlife management is limited by uncontrolled and often unrecognized environmental variation, by limited capabilities to observe and control animal populations, and by a lack of understanding about the biological processes driving population dynamics. In this paper I describe a comprehensive framework for management that includes multiple models and likelihood values...
Movements and survival of lark bunting fledglings
A. A. Yackel Adams, S. K. Skagen, R.D. Adams
2001, The Condor (103) 643-647
We quantified post-fledging pre-independence behavior and survival in Lark Buntings (Calamospiza melanocorys) using radio-telemetry. Brood division was recorded in six broods and was maintained throughout the observed fledgling care period. Chicks were capable of short flights (up to 25 m) by fledgling day 6 and longer flights (to 100 m)...
Snow cover and snow goose Anser caerulescens caerulescens distribution during spring migration
Jerry W. Hupp, Amy B. Zacheis, R. Michael Anthony, Donna G. Robertson, Wallace P. Erickson, Kelly C. Palacios
2001, Wildlife Biology (7) 65-76
Arctic geese often use spring migration stopover areas when feeding habitats are partially snow covered. Melting of snow during the stopover period causes spatial and temporal variability in distribution and abundance of feeding habitat. We recorded changes in snow cover and lesser snow goose Anser caerulescens caerulescens distribution on a...
Demonstration of significant abiotic iron isotope fractionation in nature
T.D. Bullen, A. F. White, C.W. Childs, D.V. Vivit, M.S. Schultz
2001, Geology (29) 699-702
Field and laboratory studies reveal that the mineral ferrihydrite, formed as a result of abiotic oxidation of aqueous ferrous to ferric Fe, contains Fe that is isotopically heavy relative to coexisting aqueous Fe. Because the electron transfer step of the oxidation process at pH >5 is essentially irreversible and should...
Accumulation of 2,3,7,8-tetrachlorodibenzo-p-dioxin by rainbow trout (Onchorhynchus mykiss) at environmentally relevant dietary concentrations
Paul D. Jones, Kurunthachalam Kannan, John L. Newsted, Donald E. Tillitt, Lisa L. Williams, John P. Giesy
2001, Environmental Toxicology and Chemistry (20) 344-350
Rainbow trout were fed a diet containing 1.8, 18, or 90 pg/g 3H-2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for up to 320 d. Concentrations of TCDD were determined in muscle, liver, and ovaries at 100, 150, 200, and 250 d. Concentrations of TCDD reached an apparent steady-state concentration in liver after 100 d of...
Performance of a proposed determinative method for p-TSA in rainbow trout fillet tissue and bridging the proposed method with a method for total chloramine-T residues in rainbow trout fillet tissue
J.R. Meinertz, G. R. Stehly, W.H. Gingerich, Shari L. Greseth
2001, Journal of AOAC International (84) 1332-1336
Chloramine-T is an effective drug for controlling fish mortality caused by bacterial gill disease. As part of the data required for approval of chloramine-T use in aquaculture, depletion of the chloramine-T marker residue (para-toluenesulfonamide; p-TSA) from edible fillet tissue of fish must be characterized. Declaration of p-TSA as the marker...
International collaboration: The cornerstone of satellite land remote sensing in the 21st century
G. Bryan Bailey, Donald T. Lauer, David M. Carneggie
2001, Space Policy (17) 161-169
Satellite land remotely sensed data are used by scientists and resource managers world-wide to study similar multidisciplinary earth science problems. Most of their information requirements can be met by a small number of satellite sensor types. Moderate-resolution resource satellites and low-resolution environmental satellites are the most prominent of these, and...