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111.
Common ravens are usually rather shy birds around their nests and avoid nesting too near human activity. We here report the use of overpasses along heavily traveled Interstate Highway 84 in Idaho and Utah for nest placement. Nests are within 6 m of passing vehicles.  相似文献   
112.
Vegetation characteristics of 15 sagebrush community types identified on the Humboldt National Forest, northeastern Nevada, are described. A total of 218 plant species were found over the 372 relatively undisturbed rangeland communities sampled. The dominant plant families encountered were the Asteraceae (45 taxa), Poaceae (32 taxa), Scrophulariaceae (14 taxa), and the Fabaceae (12 taxa). Average annual dry weight production of the community types ranged from about 400 kg/ha/yr on types with Artemisia nova as the dominant sagebrush species to 1,200 kg/ha/yr on some A. tridentata ssp. vaseyana community types. A general increase in species richness and vegetation plus litter ground cover was observed within community types as the dominant sagebrush species changed from A. nova to A. arbuscula to A. longiloba to A. tridentata spp. tridentata to A. tridentata ssp. vaseyana . Major differences in plant species production and constancy exist between the sagebrush community types studied.  相似文献   
113.
New synonomy is proposed as follows: Metacorthylus Blandford (= Paracorthylus Wood), Corthylus spinifer Schwarz (= Corthylus tomentosus Schedl), Cryptocarinus brevicollis Eggers ( = Cryptocarenus coronatus Wood), Dendrocranulus guatemalensis (Hopkins), n. comb. (= Dendrocranulus parallelus Schedl), Dendroterus mexicanus Blandford (= Conophthocranulus umbratus Schedl), Hypothenemus cylindricus (Hopkins) (= Hypothenemus guadeloupensis Schedl), Hypothenemus erectus LeConte (= Stephanoderes discedens Schedl), Hypothenemus javanus (Eggers) (= Stephanoderes pistor Schedl, Stephanoderes prosper Schedl), Xyleborus pseudotenuis Schedl (= Xyleborus tenuis Schedl), and Xyleborus villosulus Blandford (= Xyleborus coccotrypoides Eggers, villosus Schedl). Scolytodes punctiferus n. n. is proposed for Scolytodes punctifer Wood, 1971 (nec Wood 1969). The following species are named as new to science: Amphicranus argutus, A. fulgidus, A. micans, Pityophthorus inops, P. debilis, P. strictus. P. galeritus. P. sobrinus, P. laetus, P. lenis, P. conspectus P. medialis (Costa Rica), P. perexiguus (Costa Rica and Panama), P. scitulus (Panama), P. costatulus, P. costabilis, P. detentus, P. nebulosus, P. melanurus, P. indigens, P. burserae, P. molestus, P. diligens, P. corruptus (Mexico), P. tenax, P. nugalis, P. minutalis (Guatemala), P. nemoralis, P. morosus, P. hermosus (Honduras), Araptus gracilens (Mexico).  相似文献   
114.
A bite by Chiracanthium mildei L. Koch is described.  相似文献   
115.
116.
The known Mountain Plover population breeding on the Myton Bench, Duchesne County, Utah, is small, composed roughly of 30 adults and young after each breeding season. Currently, its location is peripheral to the species main range. This shrub-steppe breeding habitat differs from the shortgrass prairie habitat with which this bird is historically associated. Between 1996 and 1998 we made observations at nesting sites located consistently in 2 concentrated areas surrounded by large tracts of similar habitat. Activity may be focused in these specific areas because of breeding-site fidelity; this behavior is common among most shorebirds and has been documented for the Mountain Plover in Colorado. Also, Mountain Plovers are social and tend to choose nest sites near others. Most nests in Utah were located within close proximity of mounds of white-tailed prairie dogs ( Cynomys leucurus ), and all were situated near roadways or oil well pads. Mountain Plovers were often observed with broods on these bare areas at night. We conclude that Mountain Plovers on the Myton Bench are distributed in clumped breeding colonies within large areas of apparently favorable habitat.  相似文献   
117.
Miloderes allredi, from Utah, and M. tingi, from California, are described as new to science.  相似文献   
118.
Nest-boxes were monitored from 1988 to 1992 on 5 grids in the pinyon-juniper ( Pinus-Juniperus ) woodlands of the White and Inyo Mountains, California, to determine breeding phenology and productivity of cavity-nesting birds, and characteristics of used and non-used nest-boxes. We found a total of 112 nests of 6 species. Bewicks Wrens ( Thryomanes bewicki i; 64 nests), Mountain Chickadees ( Poecile gambeli ; 18), Ash-throated Flycatchers ( Myiarchus cinerascens ; 12), and Juniper Titmice ( Baeolophus ridgwayi ; 11) were the most common species utilizing the boxes. Nest phenology and numbers of young were similar to values reported elsewhere in the literature for the species, although nesting success for Mountain Chickadees appeared lower in our study. Chickadees were associated with relatively dense, mature vegetation on southern slopes. Juniper Titmice used areas with tall juniper shrubs and generally sparse vegetation. Bewicks Wrens used areas with short trees, sparse vegetation, and many stumps. Nest-boxes were underutilized (< 15% use) by most species relative to their availability and relative to detected abundances of the species. We suggest that nest-boxes can provide valuable breeding biology information and can potentially increase the productivity of rare and cavity-limited species.  相似文献   
119.
120.
Thirty-six species of aquatic Oligochaeta (Lumbriculidae, Haplotaxidae, Naididae, Tubificidae) are now known form Utah. Aquatic habitats in 27 counties were sampled, with 32 oligochaete species identified. An additional 4 species were added from other published investigations. The majority of species are cosmopolitan and occur in other areas of North America. Nais barbata, N. alpina, and N. pardalis are reported from the western United States for the first time. Ilyodrilus frantzi was found to be a major component of the oliogochaete fauna in the Great Basin lentic environment. The North American distribution of Telmatodrilus vejdovskyi is extended significantly eastward. Tow undetermined species of Tubificidae are discussed.  相似文献   
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