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New Records Of The Eastern Pipistrelle (Pipistrellus Subflavus) In Colorado, David M. Armstrong, Rick A. Adams, Karen E. Taylor May 2006

New Records Of The Eastern Pipistrelle (Pipistrellus Subflavus) In Colorado, David M. Armstrong, Rick A. Adams, Karen E. Taylor

Western North American Naturalist

No abstract provided.


Yellowstone Country: The Photographs Of Jack Richard By Mark Bagne And Bob Richard, Don G. Despain May 2006

Yellowstone Country: The Photographs Of Jack Richard By Mark Bagne And Bob Richard, Don G. Despain

Western North American Naturalist

No abstract provided.


Hawks Rest: A Season In The Remote Heart Of Yellowstone By Gary Ferguson, Jordan C. Pederson May 2006

Hawks Rest: A Season In The Remote Heart Of Yellowstone By Gary Ferguson, Jordan C. Pederson

Western North American Naturalist

No abstract provided.


Community Response Of Nontarget Species To Herbicide Application And Removal Of The Nonindigenous Invader Potentilla Recta L., R. L. Sheley, M. Kirk Denny Feb 2006

Community Response Of Nontarget Species To Herbicide Application And Removal Of The Nonindigenous Invader Potentilla Recta L., R. L. Sheley, M. Kirk Denny

Western North American Naturalist

Our main objective was to improve understanding of herbicide effects on community dynamics to refine the use of technology and advance the development of ecologically based weed management strategies. We hypothesized that native grasslands would exhibit reductions in culturally sensitive forb cover, biomass, and density relative to the rate of application of selective rangeland herbicides, and that hand-removal of sulfur cinquefoil (Potentilla recta L.) would increase indigenous species cover, biomass, density, species richness, and diversity. Treatments consisted of 3 rates each of 2,4-D + clopyralid (0.28 kg ai · ha−1 + 0.0532 kg ai · ha−1, …


Aspects Of Sacramento Pikeminnow Biology In Nearshore Habitats Of The Sacramento–San Joaquin Delta, California, Matthew L. Nobriga, Frederick Feyrer, Randall D. Baxter Feb 2006

Aspects Of Sacramento Pikeminnow Biology In Nearshore Habitats Of The Sacramento–San Joaquin Delta, California, Matthew L. Nobriga, Frederick Feyrer, Randall D. Baxter

Western North American Naturalist

We documented distribution, relative abundance, diet composition, and body condition of Sacramento pikeminnow Ptychocheilus grandis during 2001 and 2003 at 5 sites in the Sacramento–San Joaquin Delta, California. Sacramento pikeminnow densities in nearshore habitats were higher in 2003 than 2001. In both years, spatial distribution of beach seine densities was similar. There were no significant differences in density among sampling sites except for the southernmost site where the catch was near zero. Based on rotary screw-trap data from a 6th site, we found relative abundance of Sacramento pikeminnow entering the Delta via an artificial floodplain was positively correlated with flow. …


Recovery And Germinability Of Native Seed Fed To Cattle, Marina K. Whitacre, Christopher A. Call Feb 2006

Recovery And Germinability Of Native Seed Fed To Cattle, Marina K. Whitacre, Christopher A. Call

Western North American Naturalist

Using livestock as seed dispersal agents may be an effective method for increasing species diversity on degraded and previously seeded rangelands. We quantified seed passage and recovery rates, and post-passage germinability of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young), bottlebrush squirreltail (Elymus elymoides [Raf.] Swezey), and gooseberry globemallow (Sphaeralcea grossulariaefolia [H. & A.] Rydb.) by feeding Holstein heifers seeds of each species at 3 levels (15,000; 30,000; and 60,000 seeds) over a period of 3 weeks. One-kg fecal samples were collected 1, 2, 3, and 4 days after seed ingestion. Undamaged seeds were …


Introducing The Dragonflies Of British Columbia And The Yukon By Robert A. Cannings, C. Riley Nelson Feb 2006

Introducing The Dragonflies Of British Columbia And The Yukon By Robert A. Cannings, C. Riley Nelson

Western North American Naturalist

No abstract provided.


Long-Term Fire History In Great Basin Sagebrush Reconstructed From Macroscopic Charcoal In Spring Sediments, Newark Valley, Nevada, Scott Mensing, Stephanie Livingston, Pat Barker Feb 2006

Long-Term Fire History In Great Basin Sagebrush Reconstructed From Macroscopic Charcoal In Spring Sediments, Newark Valley, Nevada, Scott Mensing, Stephanie Livingston, Pat Barker

Western North American Naturalist

We use macroscopic charcoal analysis to reconstruct fire history in sagebrush (Artemisia tridentata var. wyomingensis and A. tridentata var. tridentata), in Newark Valley, Nevada. We analyzed charcoal at continuous 1-cm intervals (~7–127 years), and pollen at 2- to 10-cm intervals (~70–263 years) in a core spanning the last 5500 cal yr BP (calendar years before present). A charcoal peak in the historic period was associated with a >1400-ha fire dated to 1986 that burned in the watershed. We reconstructed the prehistoric fire history by inferring fires from similar charcoal peaks that were significantly greater than the background charcoal …


Front Matter, Vol. 66 No. 1 Feb 2006

Front Matter, Vol. 66 No. 1

Western North American Naturalist

No abstract provided.


Occurrence, Persistence, And Expansion Of Saltcedar (Tamarix Spp.) Populations In The Great Plains Of Montana, Jason P. Sexton, Anna Sala, Kevin Murray Feb 2006

Occurrence, Persistence, And Expansion Of Saltcedar (Tamarix Spp.) Populations In The Great Plains Of Montana, Jason P. Sexton, Anna Sala, Kevin Murray

Western North American Naturalist

Saltcedar (Tamarix spp.), a shrub native to Eurasia, is associated with major alterations to wetland and riparian systems in the southwestern United States. Since the 1960s saltcedar has been naturalized in northern states of the U.S. where its growth potential and impacts are not well known. Here, we describe the occurrence, age, size, and relative cover of saltcedar populations in several river basins in central eastern Montana, USA, to identify potential patterns of spread across the region and changes in individual populations as they age. Stands were aged according to the oldest saltcedar individuals and were sampled for dominant …


Behavioral And Physiological Responses Of Eared Grebes (Podiceps Nigricollis) To Variations In Brine Shrimp (Artemia Franciscana) Densities, Joe N. Caudell, Michael R. Conover Feb 2006

Behavioral And Physiological Responses Of Eared Grebes (Podiceps Nigricollis) To Variations In Brine Shrimp (Artemia Franciscana) Densities, Joe N. Caudell, Michael R. Conover

Western North American Naturalist

Eared Grebes (Podiceps nigricollis) use the Great Salt Lake (GSL) primarily as a fall staging area. They feed on brine shrimp (Artemia franciscana) to build up energy reserves to complete their southward migration. Whereas it has been speculated that timing of grebe departure from the GSL is due to declining shrimp density, this hypothesis has not been tested. We monitored grebe weight, behavior, and departure dates to test this hypothesis and to determine the effects of declining shrimp densities on Eared Grebes during 1999, 2000, and 2001 when there were different shrimp densities. Despite differences in …


Vegetation, Soils, And Hydrogeomorphology Of Riparian Patch Types Of A Dryland River, K. J. Bagstad, S. J. Lite, J. C. Stromberg Feb 2006

Vegetation, Soils, And Hydrogeomorphology Of Riparian Patch Types Of A Dryland River, K. J. Bagstad, S. J. Lite, J. C. Stromberg

Western North American Naturalist

From a landscape perspective, riparian corridors can be viewed as mosaics of vegetation patches. We delineated 10 patch types within the floodplain of the San Pedro River (Arizona) on the basis of physiognomy, dominant overstory species, and tree size class; and we assessed differences in hydrogeomorphology, vegetation structure, plant species richness, and soil chemistry and texture. Patches of tamarisk (Tamarix), an introduced species, fell within the continuum of variation shown by other patch types in the landscape mosaic. Among the tree-dominated types, cottonwood-willow (Populus-Salix) and tamarisk patches were inundated more frequently than mesquite (Prosopis) …


Composition And Distribution Of The Milliped Tribe Pachydesmini West Of The Mississippi River (Polydesmida: Xystodesmidae), Rowland M. Shelley, Chris T. Mcallister Feb 2006

Composition And Distribution Of The Milliped Tribe Pachydesmini West Of The Mississippi River (Polydesmida: Xystodesmidae), Rowland M. Shelley, Chris T. Mcallister

Western North American Naturalist

The xystodesmid milliped tribe Pachydesmini is supported by the autapomorphic absence of bold aposematic pigmentations and possibly also by relative somatic inflexibility; it comprises 3 component genera: PachydesmusCook, 1895; Dicellarius Chamberlin, 1920; and Thrinaxoria Chamberlin and Hoffman, 1950. Three representatives occur west of the Mississippi River—P. clarus (Chamberlin), P. crassicutis crassicutis (Wood), and T. lampra (Chamberlin). New localities are documented in Louisiana and Texas, and literature records are summarized for these states and Arkansas; records of P. clarus from Cherokee County, Texas, are the westernmost in this state for the east-Nearctic xystodesmid fauna. An apparently allopatric population of …


Transverse And Longitudinal Variation In Woody Riparian Vegetation Along A Montane River, Jonathan M. Friedman, Gregor T. Auble, Edmund D. Andrews, Gwen Kittel, Richard F. Madole, Eleanor R. Griffin, Tyler M. Allred Feb 2006

Transverse And Longitudinal Variation In Woody Riparian Vegetation Along A Montane River, Jonathan M. Friedman, Gregor T. Auble, Edmund D. Andrews, Gwen Kittel, Richard F. Madole, Eleanor R. Griffin, Tyler M. Allred

Western North American Naturalist

This study explores how the relationship between flow and riparian vegetation varies along a montane river. We mapped occurrence of woody riparian plant communities along 58 km of the San Miguel River in southwestern Colorado. We determined the recurrence interval of inundation for each plant community by combining step-backwater hydraulic modeling at 4 representative reaches with Log-Pearson analysis of 4 stream gaging stations. Finally, we mapped bottomland surficial geology and used a Geographic Information System to overlay the coverages of geology and vegetation. Plant communities were distinctly arrayed along the hydrologic gradient. The Salix exigua Nuttall (sandbar willow) community occurred …


Evaluating Plant Invasions From Both Habitat And Species Perspectives, Geneva W. Chong, Yuka Otsuki, Thomas J. Stohlgren, Debra Guenther, Paul Evangelista, Cynthia Villa, Alycia Waters Feb 2006

Evaluating Plant Invasions From Both Habitat And Species Perspectives, Geneva W. Chong, Yuka Otsuki, Thomas J. Stohlgren, Debra Guenther, Paul Evangelista, Cynthia Villa, Alycia Waters

Western North American Naturalist

We present an approach to quantitatively assess nonnative plant invasions at landscape scales from both habitat and species perspectives. Our case study included 34 nonnative species found in 142 plots (0.1 ha) in 14 vegetation types within the Grand Staircase–Escalante National Monument, Utah. A plot invasion index, based on nonnative species richness and cover, showed that only 16 of 142 plots were heavily invaded. A species invasive index, based on frequency, cover, and number of vegetation types invaded, showed that only 7 of 34 plant species were highly invasive. Multiple regressions using habitat characteristics (moisture index, elevation, soil P, native …


Dietary Overlap In Giant Salamanders (Dicamptodon): Applying Null Models To Resource Partitioning, Craig A. Steele, Colin Brammer Feb 2006

Dietary Overlap In Giant Salamanders (Dicamptodon): Applying Null Models To Resource Partitioning, Craig A. Steele, Colin Brammer

Western North American Naturalist

We examined stomach contents of preserved specimens of larval Pacific giant salamander (Dicamptodon tenebrosus) and Cope's giant salamander (D. copei) collected from sympatric and allopatric stream populations. The dietary components of these specimens were used to calculate dietary overlap between the 2 species and to determine if changes in overlap existed between sympatric and allopatric populations. To statistically test overlap values, a randomization algorithm was used to construct a simulated data matrix (i.e., null model) in order to compare observed values of dietary overlap to a distribution of overlap values from the null model. Significant levels …


Use Of Artificial Basking Substrate To Detect And Monitor Pacific Pond Turtles (Emys Marmorata), Jeff A. Alvarez Feb 2006

Use Of Artificial Basking Substrate To Detect And Monitor Pacific Pond Turtles (Emys Marmorata), Jeff A. Alvarez

Western North American Naturalist

No abstract provided.


Transborder Associations Of Terrestrial Isopods (Crustacea, Isopoda, Oniscidea) Of Mexico And The United States, Joan P. Jass, Barbara R. Klausmeier Feb 2006

Transborder Associations Of Terrestrial Isopods (Crustacea, Isopoda, Oniscidea) Of Mexico And The United States, Joan P. Jass, Barbara R. Klausmeier

Western North American Naturalist

No abstract provided.


Band-Tailed Pigeon: Wilderness Bird At Risk By Worth Mathewson, Clayton M. White Feb 2006

Band-Tailed Pigeon: Wilderness Bird At Risk By Worth Mathewson, Clayton M. White

Western North American Naturalist

No abstract provided.


End Matter, Vol. 66 No. 1 Feb 2006

End Matter, Vol. 66 No. 1

Western North American Naturalist

No abstract provided.