共查询到20条相似文献,搜索用时 15 毫秒
1.
Sage-grouse ( Centrocercus spp.) were abundant in all of Utah's 29 counties at the time of European settlement wherever sagebrush ( Artemisia spp.) occurred. Greater Sage-Grouse ( C. urophasianus ) inhabited areas north and west of the Colorado River, and Gunnison Sage-Grouse ( C. minimus ) occupied suitable habitat south and east of the Colorado River. The largest Greater Sage-Grouse populations in Utah are currently restricted to suitable habitats in Box Elder, Garfield, Rich, Uintah, and Wayne Counties. A remnant breeding population of Gunnison Sage-Grouse occurs in eastern San Juan County. We stratified Greater Sage-Grouse populations (1971-2000) by counties where the 1996 to 2000 moving average for estimated spring breeding populations was > 500 (GT500) or < 500 (LT500). Males per lek declined in all populations from 1971 to 2000; however, there were consistently more males observed on GT500 than on LT500 leks. Juveniles per adult hen (including yearling hens) Greater Sage-Grouse in the 1973-2000 fall harvest in Box Elder, Rich, and Wayne Counties did not differ from 2.25, a ratio suggesting sustainable or increasing sage-grouse populations. Declines are attributed to loss, fragmentation, and degradation of sagebrush habitat. Sage-grouse conservation ultimately depends on management and enhancement of remaining sagebrush rangelands in Utah. 相似文献
2.
James V. Robinson 《西北部美国博物学家》2011,44(1)
Of the eight most frequently collected spiders at a northern Utah study site, each of two species employed one of the following hunting strategies: pursuing, web building, jumping, and ambushing. Within each pair, size differences between species were substantial for all but the ambushers. The ambushers had different seasonal activity patterns, as did the web builders. 相似文献
3.
Jack D. Brotherson 《西北部美国博物学家》2011,47(2)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Patterns of zonation along a saline meadow slope were studied. Different species associations were distributed in five zones along the slope which paralleled Utah Lake. The five zones, distinguished on the basis of dominant species and/or life form, were: saltgrass–annual weed, saltgrass-alkaligrass, saltgrass-forb, saltgrass, and spikerush. Soil, vegetation, and plant species data were taken. Patterns of change with respect to these factors were observed along the downslope gradient. Soil pH and soluble salts decreased downslope, while organic matter and moisture increased. Individual ions showed varying patterns. Vegetation and species patterns also varied with slope position. Annuals dominated the ridge tops, while sedge and rush cover were restricted to the slope base. Perennial forb distribution was shown to be correlated with elevated levels of micronutrients in the soil. 相似文献
4.
Phytoplankton studies during the summer of 1974 in Utah Lake, Utah, demonstrated the development of disjunct distributions of Aphanizomenon flos-aquae and Ceratium hirundinella. Differential response to environmental factors and competitive displacement are proposed as probable explanations for this phenomenon. 相似文献
5.
Dorald M. Allred 《西北部美国博物学家》2011,42(4)
A man bitten on the finger by a wolf spider, Lycosa sp., experienced temporary bleeding and tingling of the finger, but no other symptoms occurred. 相似文献
6.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Presently, information pertaining to migration and daily movement patterns of big game in relation to overland conveyors or large diameter pipelines is sparse. A literature review showed that moose ( Alces alces ), caribou ( Rangifer tarandus granti ), reindeer, and dall sheep ( Ovis dalli dalli ) will pass beneath or over large diameter pipeline systems. But no information was found relative to big game crossing coal conveyor systems. Mule deer ( Odocoileus hemionus ) passage beneath an overland coal conveyor in Carbon County, Utah, was studied during spring 1981. Deer avoided crossing at underpass opportunities where the clearance was less than 50 cm. Clearances between 50 and 90 cm were selected for crossing. Deer passed beneath the conveyor during day and nighttime conditions and while the conveyor was either operating or idle. Recommendations are discussed for designing conveyors and pipelines to facilitate big game passage. 相似文献
7.
David M. Armstrong 《西北部美国博物学家》2011,37(4)
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Based on a synthesis of recent work on distribution of mammals in Utah, the hierarchy of ecogeographic distributional units proposed by Durrant (1952) is reevaluated by numerical methods. Areographic faunal elements, distinguished on the basis of shapes of distributional ranges in North America, are identified. Relationships are shown between ecogeographic faunal units and areographic faunal elements, and their historical implications are discussed. 相似文献
9.
Bird species density, diversity, and species richness in relation to habitat and seasonal variations were studied in the Betatakin Canyon area of Navajo National Monument, Arizona. The two most prominent habitat types are a riparian forest deep in the canyon bottom and a mature pinyon-juniper woodland on the mesas and slopes above the canyon. One hundred thirty-five species of birds were encountered during the study and recorded by season and habitat. The avifauna assemblages demonstrate definite habitat selection into groups associated with the riparian and pinyon-juniper woodland communities. Diversity, density, and species richness were greatest in the riparian habitat during the spring and summer months. The differences in bird community composition were greater between seasons than between habitats. Pinyon pine and Gambel oak were highly selected as perch sites in the pinyon-juniper and riparian areas, respectively. 相似文献
10.
11.
12.
13.
Stanley L. Welsh 《西北部美国博物学家》2011,40(1)
This paper is the third in a series dealing with a revision of the flora of Utah. Treated herein are 9 genera and 23 species, including both commonly cultivated, escaped, and indigenous representatives. Proposed new taxa include Sphaeralcea grossulariifolia (H. and A.) Rydb. var. moorei Welsh, Sphaeralcea leptophylla (Gray) Rydb. var. janeae Welsh, and Sphaeralcea psoraloides Welsh. 相似文献
14.
15.
16.
17.
18.
19.
Eric A. Rickart 《西北部美国博物学家》2011,47(4)
A detailed list of holotypes of Recent mammals housed in the Utah Museum of Natural History is presented. 相似文献
20.
Locations of 73,219 vascular plant vouchers representing 2438 species were digitized from the Atlas of the Vascular Plants of Utah (Albee et al. 1988). Source maps consist of 1:6,000,000-scale shaded relief maps of Utah with points representing collection locations by species. Location points, representing 1 or more specimens, were transposed onto these maps from the approximately 400,000 herbarium records of 3 major universities and federal land management agencies. These source maps were digitized into an ARC/Info TM database in order to reproduce the atlas in digital form. Analysis of all locations revealed a mapping bias of the original authors to avoid placing sample locations on county boundaries and over major river corridors. A comparison between ecoregions and elevation showed that the Colorado Plateau and Wasatch/Uinta Mountains have the highest species diversity, and that areas of low elevation (1000-2000 m) have the highest number of unique species in the state. Further, species richness is related to elevation and to ecoregion boundaries. 相似文献