Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Predation (2)
- Predation risk (2)
- Pronghorn (2)
- Antilocapra americana (1)
- Asian tapeworm (1)
-
- Aspen (1)
- Birds (1)
- Blue tilapia (1)
- Bonytail chub (1)
- Bothriocephalus acheilognathi (1)
- Brachylagus idahoensis (1)
- Canis latrans (1)
- Catastrophic disturbance (1)
- Colorado pikeminnow (1)
- Cover (1)
- Cover type (1)
- Coyote (1)
- Dendroctonus rufipennis (1)
- Distribution (1)
- Disturbance (1)
- Eastern pipistrelle (1)
- Edge (1)
- Elk (1)
- Ethanol (1)
- Flooding (1)
- Frontalin (1)
- Golden Eagle (1)
- Hells Canyon (1)
- Herbivory (1)
- Humpback chub (1)
Articles 1 - 30 of 81
Full-Text Articles in Entire DC Network
Weed Control And Soil Amendment Effects On Restoration Plantings In An Oregon Grassland, Russell T. Huddleston, Truman P. Young
Weed Control And Soil Amendment Effects On Restoration Plantings In An Oregon Grassland, Russell T. Huddleston, Truman P. Young
Western North American Naturalist
The restoration of perennial grasslands in western North America often depends on effective weed control. We took advantage of a grassland restoration site on the Nature Conservancy's Agate Desert Preserve in southern Oregon (TNC 1997), where 3 sites had been previously burned, mowed, or both. At these sites we carried out a series of controlled, replicated experiments designed to test the effectiveness of 3 weed control measures: (1) sawdust, (2) glyphosate herbicide, and (3) herbicide plus an alfalfa mulch. All plots were seeded with a mix of 3 native perennial grasses. The soils of the 3 areas differing in previous …
Habitat Use Patterns Within The Home Range Of Pygmy Rabbits (Brachylagus Idahoensis) In Southeastern Idaho, Laura T. Heady, John W. Laundré
Habitat Use Patterns Within The Home Range Of Pygmy Rabbits (Brachylagus Idahoensis) In Southeastern Idaho, Laura T. Heady, John W. Laundré
Western North American Naturalist
Pygmy rabbits (Brachylagus idahoensis) are a small sagebrush (Artemisia tridentata) obligate lagomorph found within the Great Basin of northwestern United States. Because of its reliance on sagebrush, this species is thought to be experiencing a major range reduction as a result of loss of sagebrush habitat. To aid in conservation of this species, we need to better understand its use of the sagebrush environment. We estimated summer home range use patterns by relocating 5 radio-collared pygmy rabbits (3 females and 2 males) over a 24-hour cycle. We then compared soil texture, shrub density, height, and canopy …
Distributional Changes And Population Status Of Amphibians In The Eastern Mojave Desert, David F. Bradford, Jef R. Jaeger, Seth A. Shanahan
Distributional Changes And Population Status Of Amphibians In The Eastern Mojave Desert, David F. Bradford, Jef R. Jaeger, Seth A. Shanahan
Western North American Naturalist
Several amphibian species historically inhabited sparsely distributed wetlands in the Mojave Desert of western North America, habitats that have been dramatically altered or eliminated as a result of human activities. The population status and distributional changes of amphibians were investigated over a 20,000-km2 area in the eastern Mojave Desert in 2 ways. For upland sites (i.e., sites outside of major valleys and river floodplains), where wetland habitat is almost exclusively springs, encounter surveys were conducted at 128 sites in 1997–1999, and results were compared to historical (pre-1970) locality records. For lowland sites (i.e., sites within major valleys and river …
Cedar Hollow, An Early Holocene Faunal Site From Whidbey Island, Washington, George E. Mustoe, C. Richard Harington, Richard E. Morlan
Cedar Hollow, An Early Holocene Faunal Site From Whidbey Island, Washington, George E. Mustoe, C. Richard Harington, Richard E. Morlan
Western North American Naturalist
Coastal erosion at central Whidbey Island reveals a cross-section view of dune sands that contain the only known record of animals that inhabited the Pacific Northwest coast during the early Holocene. Mammal fossils include bones and teeth of deer, wolf, brown bear, and several species of rodents. A deer vertebra from basal beds yielded a 14C age of 8840 ± 50 yr BP. The faunal diversity suggests that the region was repopulated relatively quickly following the final retreat of the Cordilleran sheet. This paleofauna was quite different from that of the late Pleistocene, when the region was inhabited by …
Natural History Of A Retreat-Building Midge, Pagastia Partica, In A Regulated Reach Of The Upper Colorado River, Jeremy B. Monroe, N. Leroy Poff, Richard A. Thorp
Natural History Of A Retreat-Building Midge, Pagastia Partica, In A Regulated Reach Of The Upper Colorado River, Jeremy B. Monroe, N. Leroy Poff, Richard A. Thorp
Western North American Naturalist
The retreat-building midge Pagastia prob. partica (Roback) is an abundant and conspicuous member of the benthic community of the upper Colorado River. We investigated the ecology and behavior of P. partica in this regulated stream using both qualitative observations and quantitative surveys. Our studies revealed that P. partica foraged primarily by grazing algae from their retreats and adjacent surfaces and exhibited territorial behavior toward other P. partica larvae. Pagastia partica were widely distributed among streambed surfaces but preferred those with higher biomasses of periphyton and swifter currents. The retreats of P. partica were composed largely of silk and colonized algae …
Index [And Table Of Contents To] Volume 65
Index [And Table Of Contents To] Volume 65
Western North American Naturalist
No abstract provided.
Soil Impacts Of Bristlecone Pine (Pinus Longaeva) Tree Islands On Alpine Tundra, Charleston Peak, Nevada, Laura Weiss, Aaron B. Shiels, Lawrence R. Walker
Soil Impacts Of Bristlecone Pine (Pinus Longaeva) Tree Islands On Alpine Tundra, Charleston Peak, Nevada, Laura Weiss, Aaron B. Shiels, Lawrence R. Walker
Western North American Naturalist
No abstract provided.
Great Basin Summer Range Forage Quality: Do Plants Nutrients Meet Elk Requirements?, Jeffrey L. Beck, James M. Peek
Great Basin Summer Range Forage Quality: Do Plants Nutrients Meet Elk Requirements?, Jeffrey L. Beck, James M. Peek
Western North American Naturalist
Understanding the relative ability of forages to meet the needs of prime-age females, the productive component of elk (Cervus elaphus) populations, is necessary to decipher reasons for declines and potential for population growth. Information on forage nutrient dynamics for elk on Great Basin summer–fall ranges is lacking. Our primary objectives were to estimate nutrient levels in common elk forage species in northeastern Nevada at 3 time periods and evaluate whether nutrient levels met good requirements for lactating cow elk at time periods across summers. We compared crude protein, digestible energy, and macromineral levels in 2 forbs, 6 grasses, …
Morphology And Taxonomy Of Klamath Basin Suckers (Catostomidae), Douglas F. Markle, Martin R. Cavalluzzi, David C. Simon
Morphology And Taxonomy Of Klamath Basin Suckers (Catostomidae), Douglas F. Markle, Martin R. Cavalluzzi, David C. Simon
Western North American Naturalist
We examined morphology of 4 sucker species (Catostomidae) from Klamath and Rogue River basins, Oregon and California. Different pairs of these species have been suspected of hybridizing, and field biologists have experienced difficulty identifying individuals in some areas. The suite of morphological characters used for initial identification was poorly supported by other morphometric characters but well supported by meristic characters, especially when analyses were restricted geographically. In some species sexual dimorphism was evident, with males having longer pectoral fins and females having longer pre-anal counts and measurements. Each species showed geographic differentiation, either between the Lost River subbasin and other …
The Moxee City (Washington) Mammoth: Morphostratigraphic, Taphonomic, And Taxonomic Considerations, Karl Lillquist, Steve Lundblad, Bax R. Barton
The Moxee City (Washington) Mammoth: Morphostratigraphic, Taphonomic, And Taxonomic Considerations, Karl Lillquist, Steve Lundblad, Bax R. Barton
Western North American Naturalist
A nearly complete, but highly fractured, proboscidean tusk was unearthed during parking lot construction near Moxee City in central Washington in May 2001. Schreger angle analysis revealed that the tusk was from a mammoth. AMS radiocarbon dating of the tusk established that the mammoth died 14,570 14C yr BP. The age, combined with the biogeography of proboscidean finds in the Pacific Northwest, suggests the tusk is from a Columbian mammoth (Mammuthus columbi). The condition of the tusk and its association with basalt and crystalline erratics suggest that a locally derived tusk was swept up in the advancing …
Behavioral Activities And Breeding Success Of Willow Flycatchers In The Sierra Nevada, Denise E. Soroka, Michael L. Morrison
Behavioral Activities And Breeding Success Of Willow Flycatchers In The Sierra Nevada, Denise E. Soroka, Michael L. Morrison
Western North American Naturalist
Observing survival and how individuals allocate time can provide insight into a species' ability to tolerate environmental constraints. We studied the Willow Flycatcher (Empidonax trallii) in the Sierra Nevada to determine if there were behavioral differences between pairs that successfully produced offspring and those that did not. This information will advance understanding of why these birds are declining in the Sierra Nevada and contribute to recommendations that may help to conserve them. We studied birds in 13 meadows in 2000 and 2001 using continuous focal-animal observations. Of the 43 territories we observed, 11 were occupied by males who …
Relationship Of Diurnal Habitat Use Of Native Stream Fishes Of The Eastern Great Basin To Presence Of Introduced Salmonids, Darren G. Olsen, Mark C. Belk
Relationship Of Diurnal Habitat Use Of Native Stream Fishes Of The Eastern Great Basin To Presence Of Introduced Salmonids, Darren G. Olsen, Mark C. Belk
Western North American Naturalist
Introduced brown trout, Salmo trutta, are common to many streams of western North America. However, the ecological interactions between brown trout and native stream fishes are not well understood, particularly the nature and extent of antipredator responses of native species. We examined the effects of brown trout presence on diurnal habitat use by 2 small native fishes at a mesohabitat scale (e.g., pool, riffle, run, backwater, etc.). Adult and juvenile southern leatherside chub (Lepidomeda aliciae, formerly Gila copei) and juvenile mountain sucker (Catostomus platyrhynchus) were located in main channel pools in the absence of …
Systematic Relationships Of Pityopus Californicus Inferred From Large Ribosomal Subunit (26s) Rrna Gene Sequences, Ray Neyland
Systematic Relationships Of Pityopus Californicus Inferred From Large Ribosomal Subunit (26s) Rrna Gene Sequences, Ray Neyland
Western North American Naturalist
Pityopus californicus is a rare mycoheterotrophic herb that occurs in coniferous and mixed forests of western North America. Previous authors have speculated that Pityopus californicus is not a true species but is a recurring hybrid. The reputed parental candidates of P. californicus include the closely related Pleuricospora fimbriolata, Hemitomes congestum, and Monotropa hypopithys. However, a phylogenetic analysis of large ribosomal subunit (26S) rRNA gene sequences suggests that Pityopus californicus is sister to Monotropa hypopithys and not a recurring hybrid.
Nutritional Condition Of Elk In Rocky Mountain National Park, Louis C. Bender, John G. Cook
Nutritional Condition Of Elk In Rocky Mountain National Park, Louis C. Bender, John G. Cook
Western North American Naturalist
We tested the hypothesis that elk in Rocky Mountain National Park (RMNP) were at ecological carrying capacity by determining herd-specific levels of nutritional condition and fecundity. Ingesta-free body fat levels in adult cows that were lactating were 10.6% (s = 1.7; range = 6.2–15.4) and 7.7% (s = 0.5; range = 5.9–10.1) in November 2001 for the Horseshoe and Moraine Park herds, respectively. Cows that were not lactating were able to accrue significantly more body fat: 14.0% (s = 1.1; range = 7.7–19.3) and 11.5% (s = 0.8; range = 8.6–15.1) for the Horseshoe and Moraine …
Archaeological Record Of Native Fishes Of The Lower Colorado River: How To Identify Their Remains, Kenneth W. Gobalet, Thomas A. Wake, Kalie L. Hardin
Archaeological Record Of Native Fishes Of The Lower Colorado River: How To Identify Their Remains, Kenneth W. Gobalet, Thomas A. Wake, Kalie L. Hardin
Western North American Naturalist
Archaeological sites in the Salton Basin of southeastern California and along the lower Colorado River provided opportunities to determine which fish species were present prior to extirpations, environmental degradation, and the recession of Lake Cahuilla. These remains also represent the fishes exploited by Native Americans. Bonytail (Gila elegans), razorback sucker (Xyrauchen texanus), Colorado pikeminnow (Ptychocheilus lucius), striped mullet (Mugil cephalus), and machete (Elops affinis) have been recovered from 117 sites in the Salton Basin, once filled by the Colorado River forming Lake Cahuilla. Bonytail and razorback sucker comprise nearly 99% …
Pollination Needs Of Arrowleaf Balsamroot, Balsamorhiza Sagittata (Heliantheae: Asteraceae), James H. Cane
Pollination Needs Of Arrowleaf Balsamroot, Balsamorhiza Sagittata (Heliantheae: Asteraceae), James H. Cane
Western North American Naturalist
Arrowleaf balsamroot, Balsamorhiza sagittata (Pursh) Nutt, is a common, sometimes dominant, long-lived forb that flowers early in spring from the foothills to upper-montane areas of the northern Rocky Mountains and Intermountain West. Public land managers desire its seed for rangeland rehabilitation. Through manual pollination field trials, the species was found to have a mixed pollination system. It is primarily xenogamous (46% of ovules yielded plump achenes) but partially self-compatible (31% of achenes were plump). Unvisited flower heads formed virtually no mature achenes; only plump achenes contained seeds with endosperm. Freely visited flower heads in 2 populations produced as many achenes …
Modeling Global Warming Scenarios In Greenback Cutthroat Trout (Oncorhynchus Clarki Stomias) Streams: Implications For Species Recovery, Scott J. Cooney, Alan P. Covich, Paul M. Lukacs, Amy L. Harig, Kurt D. Fausch
Modeling Global Warming Scenarios In Greenback Cutthroat Trout (Oncorhynchus Clarki Stomias) Streams: Implications For Species Recovery, Scott J. Cooney, Alan P. Covich, Paul M. Lukacs, Amy L. Harig, Kurt D. Fausch
Western North American Naturalist
Changes in global climate may exacerbate other anthropogenic stressors, accelerating the decline in distribution and abundance of rare species throughout the world. We examined the potential effects of a warming climate on the greenback cutthroat trout (Oncorhynchus clarki stomias), a resident salmonid that inhabits headwater streams of the central Rocky Mountains. Greenbacks are outcompeted at lower elevations by nonnative species of trout and currently are restricted to upper-elevation habitats where barriers to upstream migration by nonnatives are or have been established. We used likelihood-based techniques and information theoretics to select models predicting stream temperature changes for 10 streams …
Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, Erik A. Beever, David A. Pyke, Jeanne C. Chambers, Fred Landau, Stanley D. Smith
Monitoring Temporal Change In Riparian Vegetation Of Great Basin National Park, Erik A. Beever, David A. Pyke, Jeanne C. Chambers, Fred Landau, Stanley D. Smith
Western North American Naturalist
Disturbance in riparian areas of semiarid ecosystems involves complex interactions of pulsed hydrologic flows, herbivory, fire, climatic effects, and anthropogenic influences. We resampled riparian vegetation within ten 10-m × 100-m plots that were initially sampled in 1992 in 4 watersheds of the Snake Range, east central Nevada. Our finding of significantly lower coverage of grasses, forbs, and shrubs within plots in 2001 compared with 1992 was not consistent with the management decision to remove livestock grazing from the watersheds in 1999. Change over time in cover of life-forms or bare ground was not predicted by scat counts within plots in …
Collection Of Asian Tapeworm (Bothriocephalus Acheilognathi) From The Yampa River, Colorado, David Ward
Collection Of Asian Tapeworm (Bothriocephalus Acheilognathi) From The Yampa River, Colorado, David Ward
Western North American Naturalist
No abstract provided.
Inland Fishes Of California By Peter B. Moyle, Andrew L. Sheldon
Inland Fishes Of California By Peter B. Moyle, Andrew L. Sheldon
Western North American Naturalist
No abstract provided.
Variation In Lewisia Kelloggii (Portulacaceae) With Description Of A New Species Endemic To Idaho, Barbara L. Wilson, Valerie D. Hipkins, Edna Rey-Vizgirdas, Thomas N. Kaye
Variation In Lewisia Kelloggii (Portulacaceae) With Description Of A New Species Endemic To Idaho, Barbara L. Wilson, Valerie D. Hipkins, Edna Rey-Vizgirdas, Thomas N. Kaye
Western North American Naturalist
Lewisia kelloggii has been understood as a rare plant with a disjunct range in California and Idaho. Examination of herbarium specimens and analysis of isozymes in 6 Idaho and 7 California populations revealed consistent differences between plants of the 2 states. Fixed differences in alleles at 2 loci (AAT2 and PGI1) distinguished Idaho from California plants. Genetic identities based on isozymes between Idaho and California populations averaged 0.58, lower than the average for congeneric plant species. Idaho plants were smaller than most California plants, but California plants were variable. The most consistent morphological difference between Idaho and California specimens was …
Comparing The Effects Of Granivorous Rodents On Persistence Of Indian Ricegrass (Oryzopsis Hymenoides) Seeds In Mixed And Monospecific Seed Patches, Joseph A. Veech, Stephen H. Jenkins
Comparing The Effects Of Granivorous Rodents On Persistence Of Indian Ricegrass (Oryzopsis Hymenoides) Seeds In Mixed And Monospecific Seed Patches, Joseph A. Veech, Stephen H. Jenkins
Western North American Naturalist
In desert environments seeds are often heterogeneously distributed in small patches that vary in number of seed species and in seed density. Because seed harvest by rodents is often density dependent (a larger proportion of seeds is removed from high-density seed patches than from low-density patches), the proportion of residual or post-harvest seeds should be greater in low-density patches. In addition, seed preference can affect harvest. We tested whether the residual proportion of a highly preferred seed (Indian ricegrass, Oryzopsis hymenoides) was less when in a seed patch with a 2nd species (mixed-species patch) than when in a monospecific …
Evaluating Lek Occupancy Of Greater Sage-Grouse In Relation To Landscape Cultivation In The Dakotas, Joe T. Smith, Lester D. Flake, Kenneth F. Higgins, Gerald D. Kobriger, Collin G. Homer
Evaluating Lek Occupancy Of Greater Sage-Grouse In Relation To Landscape Cultivation In The Dakotas, Joe T. Smith, Lester D. Flake, Kenneth F. Higgins, Gerald D. Kobriger, Collin G. Homer
Western North American Naturalist
Greater Sage-Grouse (Centrocercus urophasianus) have been declining in many states and provinces of North America, and North and South Dakota hold no exception to these declines. We studied effects of cultivated land on Greater Sage-Grouse lek abandonment in North and South Dakota. Landscape-level data were assessed using satellite imagery within a geographic information system. Comparisons were made of 1972–1976 and 1999–2000 percent cultivated and noncultivated land. These comparisons were made between land uses surrounding active leks versus inactive leks, active leks versus random locations, and abandoned regions versus active regions. The 1999–2000 imagery illustrated that percent cultivated land …
A Comprehensive Ecological Land Classification For Utah's West Desert, Neil E. West, Frank L. Dougher, Gerald S. Manis, R. Douglas Ramsey
A Comprehensive Ecological Land Classification For Utah's West Desert, Neil E. West, Frank L. Dougher, Gerald S. Manis, R. Douglas Ramsey
Western North American Naturalist
Land managers and scientists need context in which to interpolate between or extrapolate beyond discrete field points in space and time. Ecological classification of land (ECL) is one way by which these relationships can be made. Until regional issues emerged and calls were made for ecosystem management (EM), each land management institution chose its own ECLs. The need for economic efficiency and the increasing availability of geographic information systems (GIS) compel the creation of a national ECL so that communication across ownership boundaries can occur. ECOMAP, an 8-level, top-down, nested, hierarchical, multivariable approach designed to solve this problem has been …