Sex differences in territorial behavior exhibited by the spotted hyena (Hyaenidae, Crocuta crocuta)
Erin E. Boydston, Toni Lyn Morelli, Kay E. Holekamp
2001, Ethology (107) 369-385
Spotted hyenas (Crocuta crocuta) are gregarious carnivores that defend group territories against encroachment by neighboring conspecifics. Here we monitored the behavior of members of one clan of free-ranging spotted hyenas during border patrols, ‘wars’ with neighboring clans, and other interactions with alien intruders, to document differences between the sexes in...
Recent formation of arroyos in the Little Missouri Badlands of southwestern North Dakota
M.A. Gonzalez
2001, Geomorphology (38) 63-84
In the Little Missouri Badlands of southwestern North Dakota, the channels of ephemeral streams are incised 2 to 10 m or more into mid-to-late Holocene alluvium. The objectives of this study were to determine the timing and cause(s) of the most recent episodes of fluvial incision and to develop a...
Lack of selection for resistance to whirling disease among progeny of Colorado River rainbow trout
E.K.N. Ryce, A.V. Zale, R.B. Nehring
2001, Journal of Aquatic Animal Health (13) 63-68
We compared the resistance to whirling disease of two groups of Colorado River rainbow trout Oncorhynchus mykiss and a domestic strain of rainbow trout in a controlled laboratory challenge. These three groups represented the progeny of wild rainbow trout known to have recruited (1) during the early years of infestation...
From open to closed canopy: A century of change in Douglas-fir forest, Orcas Island, Washington
D. L. Peterson, R.D. Hammer
2001, Northwest Science (75) 262-269
During the past century, forest structure on south-facing slopes of Mount Constitution, Orcas Island, Washington, has changed from open-grown Douglas-fir (Pseudotsuga menziesii) mixed with prairie to primarily closed canopy forest. Density of open-grown Douglas-fir was approximately 7 stems/ha in the 19th century, while current density of trees in closed-canopy mature forest is 426 stems/ha....
Landscape determinants of nonindigenous fish invasions
R. M. Ross, W.A. Lellis, R. M. Bennett, C.S. Johnson
2001, Biological Invasions (3) 347-361
Much has been written about the influence of exotic or nonindigenous species on natural habitats and communities of organisms, but little is known of the physical or biological conditions that lead to successful invasion of native habitats and communities by exotics. We studied invasivity factors in headwater streams of the...
Decline of disjunct green salamander (Aneides aeneus) populations in the southern appalachians
Jeffrey D. Corser
2001, Biological Conservation (97) 119-126
Coincident with other amphibians around the world Aneides aeneus, a terrestrial plethodontid salamander, suffered a population collapse in a disjunct portion of its range in the mid-late 1970s. Long-term monitoring of seven historical green salamander populations throughout the 1990s showed a 98% decline in relative abundance since 1970. Three out...
Physiography and late Quaternary-Holocene processes of Northeastern Gulf of Mexico outer continental shelf off Mississippi and Alabama
J.V. Gardner, P. Dartnell, K. J. Sulak, B. Calder, L. Hellequin
2001, Gulf of Mexico Science (19) 132-157
High-resolution multibeam mapping of the mid- and outer continental shelf and upper slope off Mississippi and Alabama reveals a complex bathymetry that reflects conditions during the last eustatic rise and the present high stand of sea level. The most prominent bathymetric features are pinnacles and hardgrounds that are scattered throughout...
Chlorine-36, bromide, and the origin of spring water
S.N. Davis, L.D. Cecil, M. Zreda, S. Moysey
2001, Chemical Geology (179) 3-16
Natural ratios of chlorine-36 (36Cl) to stable chlorine (i.e., 36Cl/Cl ?? 10-15) vary in shallow groundwater of the United States from about 50 in coastal areas to about 1400 in the northern Rocky Mountains. Ratios lower than these indicate the presence of chloride (Cl-) that has been isolated from the...
Pesticides and amphibian declines in California, USA
Donald W. Sparling, Gary M. Fellers, Laura McConnell
2001, Environmental Toxicology and Chemistry (20) 1591-1595
Several species of anuran amphibians have undergone drastic population declines in the western United States over the last 10 to 15 years. In California, the most severe declines are in the Sierra Mountains east of the Central Valley and downwind of the intensely agricultural San Joaquin Valley. In contrast, coastal...
A comparison of susceptibility to Myxobolus cerebralis among strains of rainbow trout and steelhead field and laboratory trials
Christine L. Densmore, V. S. Blazer, Deborah D. Cartwright, W. B. Schill, J. H. Schachte, C. J. Petrie, M.V. Batur, T.B. Waldrop, A. Mack, P.S. Pooler
2001, Journal of Aquatic Animal Health (13) 220-227
Three strains of rainbow trout and steelhead Oncorhynchus mykiss were evaluated for the presence of whirling disease in field and laboratory trials. In the field exposures, fingerling Salmon River steelhead and Cayuga Lake and Randolph strains of rainbow trout were placed in wire cages in an earthen, stream-fed pond in New York...
Guidance of yearling shortnose and pallid sturgeon using vertical bar rack and louver arrays
B. Kynard, Martin Horgan
2001, North American Journal of Fisheries Management (21) 561-570
Some populations of shortnose sturgeon Acipenser brevirostrum and pallid sturgeon Scaphirhynchus albus have been divided by hydroelectric dams, and migration downstream past the dams likely continues. No protection for downstream migrants is presently available, and the behavior of sturgeon to guidance structures has not been studied. We conducted experiments in a 5.4-m-long × 1.5-m-wide...
Disturbance to wintering western snowy plovers
Kevin D. Lafferty
2001, Biological Conservation (101) 315-325
In order to better understand the nature of disturbances to wintering snowy plovers, I observed snowy plovers and activities that might disturb them at a beach near Devereux Slough in Santa Barbara, California, USA. Disturbance (activity that caused plovers to move or fly) to wintering populations of threatened western snowy...
Utility of stable isotope analysis in studying foraging ecology of herbivores: Examples from moose and caribou
Merav Ben-David, Einav Shochat, Layne G. Adams
2001, Alces (37) 421-434
Recently, researchers emphasized that patterns of stable isotope ratios observed at the individual level are a result of an interaction between ecological, physiological, and biochemical processes. Isotopic models for herbivores provide additional complications because those mammals consume foods that have high variability in nitrogen concentrations. In addition, distribution of amino...
Some simple guides to finding useful information in exploration geochemical data
D.A. Singer, R. Kouda
2001, Natural Resources Research (10) 137-147
Most regional geochemistry data reflect processes that can produce superfluous bits of noise and, perhaps, information about the mineralization process of interest. There are two end-member approaches to finding patterns in geochemical data—unsupervised learning and supervised learning. In unsupervised learning, data are processed and the geochemist is given the task...
Experimental repatriation of boreal toad (Bufo boreas) eggs, metamorphs, and adults in Rocky Mountain National Park
E. Muths, T. L. Johnson, P.S. Corn
2001, Southwestern Naturalist (46) 106-113
The boreal toad (Bufo boreas) is an endangered species in Colorado and is considered a candidate species for federal listing by the United States Fish and Wildlife Service. Boreal toads are absent from many areas of suitable habitat in the Southern Rocky Mountains of Colorado presumably due to a combination...
Geologic coal assessment: The interface with economics
E. D. Attanasi
2001, Natural Resources Research (10) 189-195
Geologic resource assessments describe the location, general characteristics, and estimated volumes of resources, whether in situ or technically recoverable. Such compilations are only an initial step in economic resource evaluation. This paper identifies, by examples from the Illinois and Appalachian basins, the salient features of a geologic assessment that assure...
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...
Physiological variation among native and exotic winter annuals associated with microphytic soil crusts in the Mojave Desert
Lesley DeFalco, James K. Detling, C. Richard Tracy, Steven D. Warren
2001, Plant and Soil (234) 1-14
Microbiotic crusts are important components of many aridland soils. Research on crusts typically focuses on the increase in soil fertility due to N-fixing micro-organisms, the stabilization of soils against water and wind erosion and the impact of disturbance on N-cycling. The effect of microbiotic crusts on the associated plant community...
Evolution of the December 14, 1989 precursory long-period event swarm at Redoubt volcano, Alaska
C.D. Stephens, B. A. Chouet
2001, Journal of Volcanology and Geothermal Research (109) 133-148
The intermittency pattern and evolution in waveforms of long-period (LP) seismic events during the intense, 23-h swarm that preceded the December 14, 1989 eruption of Redoubt volcano are investigated. Utilizing cross correlation to exploit the high degree of similarity among waveforms, a substantially more complete event catalog is generated than...
Statistical self-similarity of hotspot seamount volumes modeled as self-similar criticality
S.F. Tebbens, S.M. Burroughs, C.C. Barton, D. F. Naar
2001, Geophysical Research Letters (28) 2711-2714
The processes responsible for hotspot seamount formation are complex, yet the cumulative frequency-volume distribution of hotspot seamounts in the Easter Island/Salas y Gomez Chain (ESC) is found to be well-described by an upper-truncated power law. We develop a model for hotspot seamount formation where uniform energy input produces events initiated...
New digital magnetic anomaly database for North America
C. A. Finn, M. Pilkington, A. Cuevas, I. Hernandez, Jaime Urrutia
2001, The Leading Edge (20) 870-872
The Geological Survey of Canada (GSC), U.S. Geological Survey (USGS), and Consejo de Recursos Minerales of Mexico (CRM) are compiling an upgraded digital magnetic anomaly database and map for North America. This trinational project is expected to be completed by late 2002....
Smectite diagenesis, pore-water freshening, and fluid flow at the toe of the Nankai wedge
K. M. Brown, D.M. Saffer, B.A. Bekins
2001, Earth and Planetary Science Letters (194) 97-109
The presence of low-chloride fluids in the lowermost sediments drilled at Ocean Drilling Program Site 808, at the Nankai accretionary wedge, has been considered as prime evidence for long-distance, lateral fluid flow from depth. Here, we re-evaluate the potential role of in situ reaction of smectite (S) to illite (I)...
A portfolio approach to evaluating natural hazard mitigation policies: An application to lateral-spread ground failure in coastal California
R. L. Bernknopf, L.B. Dinitz, S.J.M. Rabinovici, A.M. Evans
2001, International Geology Review (43) 424-440
In the past, efforts to prevent catastrophic losses from natural hazards have largely been undertaken by individual property owners based on site—specific evaluations of risks to particular buildings. Public efforts to assess community vulnerability and encourage mitigation have focused on either aggregating site—specific estimates or adopting standards based upon broad...
Salmonberry and salal annual aerial stem production: The maintenance of shrub cover in forest stands
J. C. Tappeiner II, J. Zasada, D. Huffman, L. Ganio
2001, Canadian Journal of Forest Research (31) 1629-1638
Annual sprouting of aerial stems and ramets enables populations of salmonberry (Rubus spectabilis Pursh), salal (Gaultheria shallon Pursh), and probably other forest shrubs to maintain dense covers (>20 000 stems/ha). We studied annual stem production of salmonberry on cut (all stems cut within 15 cm of the ground) and uncut...
Distribution of fine-scale mantle heterogeneity from observations of Pdiff coda
P.S. Earle, P.M. Shearer
2001, Bulletin of the Seismological Society of America (91) 1875-1881
We present stacked record sections of Global Seismic Network data that image the average amplitude and polarization of the high-frequency Pdiff coda and investigate their implications on the depth extent of fine-scale (~10 km) mantle heterogeneity. The extended 1-Hz coda lasts for at least 150 sec and is observed to...
