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Wildlife Use Of Douglas-Fir Dwarf Mistletoe Witches' Brooms In The Southwest, Shaula J. Hedwall, Robert L. Mathiasen Dec 2006

Wildlife Use Of Douglas-Fir Dwarf Mistletoe Witches' Brooms In The Southwest, Shaula J. Hedwall, Robert L. Mathiasen

Western North American Naturalist

We evaluated wildlife use of witches' brooms associated with infection by Douglas-fir dwarf mistletoe (Arceuthobium douglasii) in 6 mixed-conifer study areas in Arizona and 2 areas in New Mexico. We climbed 153 infected Douglas-firs (Pseudotsuga menziesii) and examined 706 witches' brooms for evidence of wildlife use. Even though we observed evidence of use by birds, most wildlife use was by small mammals, particularly red squirrels (Tamiasciurus hudsonicus). Red squirrels used witches' brooms for nesting, foraging, caching, and as latrines. Witches' brooms classified as Type II or III brooms, located close to the main bole …


Characterization Of The Dorsal Skin Gland Of The Texas Kangaroo Rat, Dipodomys Elator (Rodentia: Heteromyidae), Frederick B. Stangl Jr., Jim R. Goetze, Michael M. Shipley, Desiree A. Early Dec 2006

Characterization Of The Dorsal Skin Gland Of The Texas Kangaroo Rat, Dipodomys Elator (Rodentia: Heteromyidae), Frederick B. Stangl Jr., Jim R. Goetze, Michael M. Shipley, Desiree A. Early

Western North American Naturalist

The dorsal skin gland appears to be a sexually dimorphic character for all species of Dipodomys; however, this feature has not been characterized for most taxa. Previous studies of several species have demonstrated the histological uniqueness of the gland in D. spectabilis. Other attempts to correlate seasonal variation in gland size with reproductive patterns have met with mixed success. An examination of the dorsal skin glands of 333 museum study skins of adult Dipodomys elator demonstrated a July–August size decrease in both sexes, although the glands of males were larger and more variable in size than those of …


End Matter, Vol. 66 No. 4 Dec 2006

End Matter, Vol. 66 No. 4

Western North American Naturalist

No abstract provided.


Serologic Survey Of The Island Spotted Skunk On Santa Cruz Island, Victoria J. Bakker, Dirk H. Van Vuren, Kevin R. Crooks, Cheryl A. Scott, Jeffery T. Wilcox, David K. Garcelon Dec 2006

Serologic Survey Of The Island Spotted Skunk On Santa Cruz Island, Victoria J. Bakker, Dirk H. Van Vuren, Kevin R. Crooks, Cheryl A. Scott, Jeffery T. Wilcox, David K. Garcelon

Western North American Naturalist

Two rare endemic carnivores occur on California's northern Channel Islands: island spotted skunks (Spilogale gracilis amphiala) and island foxes (Urocyon littoralis). As insular carnivores, both may be particularly vulnerable to novel pathogens. We tested sera from 31 island spotted skunks on Santa Cruz Island, where both skunks and foxes occur sympatrically, to establish their exposure to disease agents. One skunk (3%) tested positive for canine heartworm, and 3 skunks (10%) tested positive for canine parvovirus. None showed evidence of exposure to canine adenovirus, canine distemper virus, canine herpesvirus, Leptospira bacteria (serovars pomona, canicola, and …


Stand-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman Dec 2006

Stand-Level Herbivory In An Old-Growth Conifer Forest Canopy, David C. Shaw, Kristina A. Ernest, H. Bruce Rinker, Margaret D. Lowman

Western North American Naturalist

Herbivory is an important ecological process in forest canopies but is difficult to measure, especially for whole stands. We used the Wind River Canopy Crane in Washington State to access 101 randomly-located sample points throughout the forest canopy. This provided a relatively quick and convenient way to estimate herbivory for a whole stand. The overall level of herbivory was estimated at 1.6% of leaf area. The distribution was strongly skewed to the lower canopy where broad-leafed species experienced higher levels of herbivory. Herbivory averaged 0.3% in conifers and 13.5% in broad-leafed species. Fully half of the sample points had no …


Populations And Habitat Relationships Of Piute Ground Squirrels In Southwestern Idaho, Karen Steenhof, Eric Yensen, Michael N. Kochert, Kenneth L. Gage Dec 2006

Populations And Habitat Relationships Of Piute Ground Squirrels In Southwestern Idaho, Karen Steenhof, Eric Yensen, Michael N. Kochert, Kenneth L. Gage

Western North American Naturalist

Piute ground squirrels (Spermophilus mollis idahoensis) are normally above ground from late January until late June or early July in the Snake River Birds of Prey National Conservation Area in southwestern Idaho. In 2002 they were rarely seen above ground after early May. Because of the ecological importance of ground squirrels for nesting raptors and other species, we sought to determine the reasons for their early disappearance. We sampled 12 sites from January 2003 through March 2003 to determine if a population crash had occurred in 2002. Tests indicated that Piute ground squirrels had not been exposed to …


Testing Hypothesized Evolutionary Shifts Toward Stress Tolerance In Hybrid Helianthus Species, Larry C. Brouillette, Maheteme Gebremedhin, David M. Rosenthal, Lisa A. Donovan Dec 2006

Testing Hypothesized Evolutionary Shifts Toward Stress Tolerance In Hybrid Helianthus Species, Larry C. Brouillette, Maheteme Gebremedhin, David M. Rosenthal, Lisa A. Donovan

Western North American Naturalist

We examined how plant traits related to growth and resource use have evolved during hybrid speciation and specialization into stressful habitats. Two desert sunflower species of homoploid hybrid origin are endemic to habitats with lower soil nutrient levels than those of their ancestral parent species. We hypothesized that the hybrid species would exhibit greater tolerance to low levels of soil nutrients than their parental species. The 2 hybrid species, Helianthus anomalus and H. deserticola, and their parental species, H. annuus and H. petiolaris, were compared for plant traits and growth through reproduction under 3 nutrient levels in a …


Long-Term Effects Of Tebuthiuron On Bromus Tectorum, Dana M. Blumenthal, Urszula Norton, Justin D. Derner, Jean D. Reeder Dec 2006

Long-Term Effects Of Tebuthiuron On Bromus Tectorum, Dana M. Blumenthal, Urszula Norton, Justin D. Derner, Jean D. Reeder

Western North American Naturalist

Use of herbicides to thin dense stands of Artemisia spp. (sagebrush) can free up resources for herbaceous plants and increase forage production, but may also facilitate weed invasion. We revisited a sagebrush thinning experiment in a north central Wyoming big sagebrush–grassland 11 years after application of tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N-N′-dimethylurea) to determine the long-term responses of shrubs, available soil resources, perennial grasses, and Bromus tectorum L. (downy brome). Tebuthiuron reduced shrub cover by more than half, from 31% in untreated plots to 15% in treated plots (P = 0.002), and increased downy brome cover approximately 4-fold, from 0.9% in untreated plots …


Microhabitat-Specific Controls On Soil Respiration And Denitrification In The Mojave Desert: The Role Of Harvester Ant Nests And Vegetation, Jeremy B. Jones, Diane Wagner Dec 2006

Microhabitat-Specific Controls On Soil Respiration And Denitrification In The Mojave Desert: The Role Of Harvester Ant Nests And Vegetation, Jeremy B. Jones, Diane Wagner

Western North American Naturalist

Seed harvesting ants (Pogonomyrmex rugosus) concentrate organic matter and nutrients near their nests and create biogeochemical hotspots in desert soil. We examined factors regulating denitrification and soil respiration in a Mojave Desert ecosystem to determine the role harvester ant colonies play in nitrogen loss and carbon mineralization. Organic matter and nutrient storage were significantly greater in colonies than under the dominant vegetation (i.e., Pleuraphis rigida, a bunch grass) and in bare soil, with standing stocks of inorganic nitrogen in colonies nearly 4-fold greater than in the other microhabitats. Soil respiration, measured with laboratory incubations, was below detection …


Effects Of Temperature On The Survival And Growth Of Age-0 Least Chub (Iotichthys Phlegethontis), Eric J. Billman, Eric J. Wagner, Ronney E. Arndt Dec 2006

Effects Of Temperature On The Survival And Growth Of Age-0 Least Chub (Iotichthys Phlegethontis), Eric J. Billman, Eric J. Wagner, Ronney E. Arndt

Western North American Naturalist

Larval and juvenile stages of many fishes require nursery habitats that provide optimal conditions for growth. Loss or degradation of these habitats limits recruitment, causing population and species declines. Least chub (Iotichthys phlegethontis), an endemic cyprinid in the Bonneville Basin, is currently restricted to a few spring complexes in Utah. This species utilizes the warm shallow spring margins as spawning and rearing habitat throughout the summer. This study was conducted to determine effects of temperature on survival and growth of age-0 least chub to understand the importance of temperature in selection of spring margins as rearing habitat. Age-0 …


Correlation Of Neighborhood Relationships, Carbon Assimilation, And Water Status Of Sagebrush Seedlings Establishing After Fire, Katherine Dicristina, Matthew Germino Dec 2006

Correlation Of Neighborhood Relationships, Carbon Assimilation, And Water Status Of Sagebrush Seedlings Establishing After Fire, Katherine Dicristina, Matthew Germino

Western North American Naturalist

Interactions of Artemisia tridentata ssp. vaseyana (mountain big sagebrush) and neighboring herbs may affect community development following fire in sagebrush steppe. Dry mass, photosynthesis, and water relations were measured for seedlings of A. tridentata ssp. vaseyana occurring at different distances from neighboring herbs in the initial growing seasons following fire, when herbs dominate plant community cover. Seedling mass significantly increased as distance to neighboring herbs increased, although a low r2 indicated that mass was also affected by other sources of variation. Carbon assimilation (Anet) was also greater for A. tridentata ssp. vaseyana seedlings in microsites farther …


Long-Term Interactions Of Climate, Productivity, Species Richness, And Growth Form In Relictual Sagebrush Steppe Plant Communities, Neil E. West, Terence P. Yorks Dec 2006

Long-Term Interactions Of Climate, Productivity, Species Richness, And Growth Form In Relictual Sagebrush Steppe Plant Communities, Neil E. West, Terence P. Yorks

Western North American Naturalist

Vegetation trends due to climatic changes are difficult to separate from disturbances caused by varying land uses. To separate climatic influences from livestock grazing and fire disturbances within sagebrush steppe, we compared vegetation structure and productivity during 2 periods (10-year sequences of data from the late 1950s to the late 1960s and 3 years in the early 1990s) at 12 stands within 3 relict areas in or near the Great Rift of southern Idaho. Year-to-year fluctuations in annual net aboveground phytomass accumulation (ANAPA) were considerable in response to varying climate during both periods. More importantly, an apparently significant increase in …


Birds Of Washington: Status And Distribution Edited By Terence R. Wahl, Bill Tweit, And Steven G. Mlodinow, Clayton M. White Dec 2006

Birds Of Washington: Status And Distribution Edited By Terence R. Wahl, Bill Tweit, And Steven G. Mlodinow, Clayton M. White

Western North American Naturalist

No abstract provided.


Ontogenetic And Habitat-Related Changes In Diet Of Late Larval And Juvenile Suckers (Catostomidae) In Upper Klamath Lake, Oregon, Douglas F. Markle, Kale Clauson Dec 2006

Ontogenetic And Habitat-Related Changes In Diet Of Late Larval And Juvenile Suckers (Catostomidae) In Upper Klamath Lake, Oregon, Douglas F. Markle, Kale Clauson

Western North American Naturalist

We describe ontogenetic patterns in the diets of shortnose and Lost River suckers (15.8–92.8 mm standard length) from Upper Klamath Lake in summer 1999. Both species made a transition from surface and planktonic prey to benthic prey at about 20–30 mm standard length, corresponding to the approximate size of the juvenile morphological transition. Surface prey was dominated by adult chironomids and undigestable pollen, while benthic prey was dominated by larval chironomids, chydorids, and ostracods. In the 15–20-mm size class, pollen made up >75% of food particles in 68% of specimens, and only 2 specimens in this size class lacked any …


A Longevity Record For Canada Lynx, Lynx Canadensis, In Western Montana, Jay A. Kolbe, John R. Squires Dec 2006

A Longevity Record For Canada Lynx, Lynx Canadensis, In Western Montana, Jay A. Kolbe, John R. Squires

Western North American Naturalist

No abstract provided.


Reviewers For 2006 Dec 2006

Reviewers For 2006

Western North American Naturalist

No abstract provided.


Index [And Table Of Contents] To Volume 66 Dec 2006

Index [And Table Of Contents] To Volume 66

Western North American Naturalist

No abstract provided.


Front Matter, Vol. 66 No. 4 Dec 2006

Front Matter, Vol. 66 No. 4

Western North American Naturalist

No abstract provided.


Invasion Biology: Critique Of A Pseudoscience By David Theodoropoulos, Howard Clark Dec 2006

Invasion Biology: Critique Of A Pseudoscience By David Theodoropoulos, Howard Clark

Western North American Naturalist

No abstract provided.


The Female Of Cnodocentron (Caenocentron) Yavapai Moulton And Stewart (Trichoptera: Xiphocentronidae), David E. Ruiter Dec 2006

The Female Of Cnodocentron (Caenocentron) Yavapai Moulton And Stewart (Trichoptera: Xiphocentronidae), David E. Ruiter

Western North American Naturalist

No abstract provided.


Raptors Of California By Hans Peeters And Pam Peeters, Clayton M. White Dec 2006

Raptors Of California By Hans Peeters And Pam Peeters, Clayton M. White

Western North American Naturalist

No abstract provided.


Ecology Of Owens Valley Vole (Microtus Californicus Vallicola), Fletcher C. Nelson, Michael L. Morrison, Roel R. Lopez, Fred E. Smeins, Nova J. Silvy Dec 2006

Ecology Of Owens Valley Vole (Microtus Californicus Vallicola), Fletcher C. Nelson, Michael L. Morrison, Roel R. Lopez, Fred E. Smeins, Nova J. Silvy

Western North American Naturalist

No abstract provided.


Fish Remains Dominate Barn Owl Pellets In Northwestern Nevada, Raymond J. Bogiatto, Jack M. Broughton, Virginia I. Cannon, Kevin Dalton, Shannon Arnold Aug 2006

Fish Remains Dominate Barn Owl Pellets In Northwestern Nevada, Raymond J. Bogiatto, Jack M. Broughton, Virginia I. Cannon, Kevin Dalton, Shannon Arnold

Western North American Naturalist

No abstract provided.


Survival And Reproduction Of Translocated Eastern Wild Turkeys In A Sparsely Wooded Landscape In Northeastern South Dakota, Roger D. Shields, Lester D. Flake Aug 2006

Survival And Reproduction Of Translocated Eastern Wild Turkeys In A Sparsely Wooded Landscape In Northeastern South Dakota, Roger D. Shields, Lester D. Flake

Western North American Naturalist

We studied the survival and reproduction of a newly introduced population of Eastern Wild Turkeys (Meleagris gallopavo silvestris) during 1999 and 2000 to determine the adaptability of this subspecies to a minimally wooded (<10%) region located north of their recorded historic distribution in South Dakota. During 1999 and 2000, the South Dakota Department of Game, Fish and Parks (SDGFP) released 111 female and 25 male turkeys from Iowa and Kentucky onto a study area in northeastern South Dakota. We used radio telemetry to monitor survival and reproduction of the females for 2 years after their initial release. Annual survival for 71 females averaged 67%. Seasonal survival was lowest in fall and highest in winter. Mortality agents included avian and mammalian predators, haying equipment, automobiles, and unknown causes. Nesting rate for the 2 years averaged 93%, and renesting rate of turkeys with failed 1st-nest attempts averaged 45%. Nest success for all nests was 50%, and 62% of females attempting to nest each year were successful in at least 1 attempt. Predation was the primary cause of nest failure during both years. Overall, 72% of brooding females successfully raised ≥1 poult to 4 weeks post-hatch while individual poult survival to 4 weeks post-hatch averaged 36%. Despite <10% woodland cover, Eastern Wild Turkeys appeared to thrive in a glacial escarpment topography north of their historic range in the northern plains.


Reviewers Needed Aug 2006

Reviewers Needed

Western North American Naturalist

No abstract provided.


Effects Of Anthropogenic Land Use On Odonata In Playas Of The Southern High Plains, K. M. Hernandez, B. A. Reece, N. E. Mcintyre Aug 2006

Effects Of Anthropogenic Land Use On Odonata In Playas Of The Southern High Plains, K. M. Hernandez, B. A. Reece, N. E. Mcintyre

Western North American Naturalist

Playas are ephemeral wetlands that are the only source of aboveground freshwater in the southern Great Plains, making them of vital importance to aquatic and amphibious animals. Playas are also highly threatened from anthropogenic land use (chiefly agriculture, which decreases hydroperiod through increased sedimentation). We examined community structure of adult odonates (dragonflies and damselflies) in playas differing in the 2 main regional forms of surrounding land use (cropland vs. grassland). Analysis of odonate diversity revealed high overlap between cropland and grassland playas. Traditional species-area theory did not fit observed patterns, as there appears to be a threshold playa size that …


Selection Of Dwarf Mistletoe–Infected Ponderosa Pines By Ips Species (Coleoptera, Scolytidae) In Northern Arizona, Shawn C. Kenaley, Robert L. Mathiasen, Carolyn M. Daugherty Aug 2006

Selection Of Dwarf Mistletoe–Infected Ponderosa Pines By Ips Species (Coleoptera, Scolytidae) In Northern Arizona, Shawn C. Kenaley, Robert L. Mathiasen, Carolyn M. Daugherty

Western North American Naturalist

Following an Ips bark beetle outbreak in 2002, mortality of ponderosa pine (Pinus ponderosa Douglas ex C. Lawson) was evaluated in 2 study areas infested with southwestern dwarf mistletoe (Arceuthobium vaginatum [Willd.] Presl subsp. cryptopodum [Engelm.] Hawksw. & Wiens) in the Coconino and Tonto National Forests, Arizona. A pairwise comparison of dwarf mistletoe ratings for live and dead ponderosa pines was conducted to determine whether dead ponderosa pines had higher dwarf mistletoe ratings than pines that were not attacked. In both study areas, dead ponderosa pines had significantly higher dwarf mistletoe ratings, indicating an association between the severity …


Rclus, A New Program For Clustering Associated Species: A Demonstration Using A Mojave Desert Plant Community Dataset, Stewart C. Sanderson, Jeffrey E. Ott, E. Durant Mcarthur, Kimball T. Harper Aug 2006

Rclus, A New Program For Clustering Associated Species: A Demonstration Using A Mojave Desert Plant Community Dataset, Stewart C. Sanderson, Jeffrey E. Ott, E. Durant Mcarthur, Kimball T. Harper

Western North American Naturalist

This paper presents a new clustering program named RCLUS that was developed for species (R-mode) analysis of plant community data. RCLUS identifies clusters of co-occurring species that meet a user-specified cutoff level of positive association with each other. The "strict affinity" clustering algorithm in RCLUS builds clusters of species whose pairwise associations all exceed the cutoff level, whereas the "coalition" clustering algorithm only requires that the mean pairwise association of the cluster exceeds the cutoff level. Both algorithms allow species to belong to multiple clusters, thus accommodating both generalist and specialist species. Using a 60-plot dataset of perennial plants occurring …


Naturalization Of Plains Cottonwood (Populus Deltoides Subsp. Monilifera) Along River Drainages West Of The Rocky Mountains, J. H. Braatne, S. J. Brunsfeld, V. D. Hipkins, B. L. Wilson Aug 2006

Naturalization Of Plains Cottonwood (Populus Deltoides Subsp. Monilifera) Along River Drainages West Of The Rocky Mountains, J. H. Braatne, S. J. Brunsfeld, V. D. Hipkins, B. L. Wilson

Western North American Naturalist

Historic botanical surveys documented that the natural distribution of the plains cottonwood (Populus deltoides subsp. monilifera) was limited to semiarid drainages east of the Rocky Mountains. Recently, a number of isolated populations of plains cottonwood have been found along the Kootenai, lower Snake, and Columbia Rivers and their tributaries. We used isozyme analysis to assess the genetic structure of these Pacific Northwest (PNW) populations in relation to native cottonwood populations east of the Rocky Mountains. These genetic data along with field surveys (dbh, age estimates) and cadastral field survey notes (mid-1800s) were used to understand the origin of …


Habitat Affinities Of Rodents In Northeastern Nevada Rangeland Communities, J. Kent Mcadoo, Mack R. Barrington, Mark A. Ports Aug 2006

Habitat Affinities Of Rodents In Northeastern Nevada Rangeland Communities, J. Kent Mcadoo, Mack R. Barrington, Mark A. Ports

Western North American Naturalist

From May 1978 through September 1980, baseline data for rodent populations were collected by livetrapping in the Saval Ranch area of northeastern Nevada. The objectives of this study were to determine species composition and relative abundance of rodents for the various range sites. The 3 most abundant and uniformly distributed species were deer mice (Peromyscus maniculatus), Great Basin pocket mice (Perognathus parvus), and least chipmunks (Neotamias minimus). Relative abundance indices and densities reported for most species were similar to those reported in other multiyear studies at similar sites. The composition and relative abundance / …