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1.
Utah prairie dogs were transplanted onto the site of a former colony, located in Capitol Reef National Park, Utah. Shrubs on the site were significantly taller than those found on active colonies in similar habitat located on the Awapa Plateau. Therefore, the transplant site afforded a test of the hypothesis that shrub height is a major inhibitory factor affecting occupation of sites by prairie dogs. Four sites of 5 ha each were used. Vegetation treatments — rotobeating, railing, and 2,4 - D herbicide — were carried out on three of the sites and the fourth was used as a control. Shrub height and percent cover were significantly reduced on all three treatment sites. Posttreatment effects on the vegetation showed that the greatest percent moisture of the herbage was found on the railed site, followed by the herbicide, rotobeaten, and control sites. Measurements of the visual obstructions to prairie dogs showed that the rotobeaten site had the greatest visibility, followed by the railed, herbicide, and control sites. Prior to release of prairie dogs on the study area, 200 artificial burrows per treatment were dug, using a power auger. In early summer, 1979, 200 Utah prairie dogs were live - trapped near Loa, Utah. An equal number by sex and age class were released on each treatment. In 1979 a significantly higher number of animals reestablished on the rotobeaten site. In 1980 and 1981 the rotobeaten and railed sites had significantly higher prairie dog numbers than the other sites. Reproduction occurred on both the rotobeaten and railed sites in 1980 and 1981. Results indicated that, when transplanting animals onto sites of former colonies presently overgrown with shrubs, the chances of a successful transplant could be increased by first reducing shrub height and density.  相似文献   

2.
Counts of Double-crested Cormorants ( Phalacrocorax auritus ) were made at 13 reservoirs and lakes in southwestern Utah during 1989-91 to determine current abundance of that species. Food habits of cormorants were studied at three of the reservoirs in 1989. Data were also collected on trout abundance during standardized gill-netting to make comparisons between cormorant numbers and trout abundance. Cormorants were observed at all waters studied except one and were generally most numerous during the spring as they migrated through the area. Estimated cormorant abundance ranged from 0 to 34 bird-days per ha and was highest at the larger, lower-elevation reservoirs. Cormorants were summer residents at several of the larger reservoirs and nested successfully at Piute Reservoir. Trout accounted for 24-81% of the diet of cormorants, with Utah chubs constituting most of the remainder of the diet. Estimates of the annual consumption of fish by cormorants ranged from 0 to 15.8 kg per ha. The index of trout abundance was inversely related to cormorant abundance ( P < .01) at the waters studied. Cormorants apparently have increased in numbers and extended their range in southwestern Utah during the past decade. This change may be the result of factors that have led to similar changes throughout North America as well as some factors unique to Utah. Methods to mitigate the impact of predation by piscivorous birds of sportfisheries are discussed. The Utah Division of Wildlife Resources has initiated a new management plan at Minersville Reservoir that incorporates piscivorous birds into sportfish management at that reservoir.  相似文献   

3.
During the 1987 deer hunt 4,250 card questionnaires were distributed to Utah hunters at nine checking stations. Return rates varied from a mean 23% when cards were simply handed to hunters, to 50% when hunters' names and telephone numbers were taken. Results concerning methodology suggest that questionnaire surveys conducted from checking stations are efficient and accurate in obtaining hunter opinions. Questionnaire results indicated that most hunters rated the Utah deer hunt as moderately satisfactory, but may prefer alternative options that would result in a higher quality hunt. The majority of hunters indicated that hunter numbers should be limited to current levels or decreased. Unretrieved kill was reported as 21 deer per 100 hunters.  相似文献   

4.
Phragmites australis (Cav.) Trin. ex Steud. (common reed), already one of the world&rsquo;s most widespread plant species, has realized rapid range expansion in coastal wetlands of North America in the past century, but little is known about P. australis range expansion in inland wetland systems. We used genetic analyses, aerial photographs, field surveys, and a greenhouse experiment to study the extent and mechanism of nonnative P. australis invasion of Utah wetlands. We collected and genetically analyzed 39 herbarium samples across the state and 225 present-day samples from northern Utah&rsquo;s major wetland complexes. All samples collected before 1993 and all samples collected outside the major wetlands of northern Utah, including some as recent as 2001, were identified as native (haplotypes A, B, D, and H). Only 10 (4%) of the present-day samples were native, each from small, discrete, low-density stands; the remaining samples were nonnative (haplotype M). Our earliest nonnative sample was collected near the Great Salt Lake in 1993. Around the Great Salt Lake, which contains 40% of Utah&rsquo;s wetlands, P. australis cover has increased from 20% to 56% over the past 27 years&mdash;an increase that appears attributable to the nonnative strain. In a 3-month-long greenhouse experiment, the nonnative haplotype grew taller, had more aboveground biomass, and had a greater above- to belowground biomass ratio than the native haplotypes regardless of nitrogen, phosphorus, or water availability. Nonnative P. australis is rapidly invading the wetlands of northern Utah. Areas in Utah where the native P. australis remains should be identified and protected. Phragmites australis (Cav.) Trin ex Steud (carrizo), una de las especies de plantas m&aacute;s ampliamente distribuida en el mundo, se ha extendido r&aacute;pidamente en los humedales costeros de Norteam&eacute;rica en el &uacute;ltimo siglo, pero se conoce poco sobre la expansi&oacute;n de P. australis en sistemas de humedales del interior. Utilizamos an&aacute;lisis gen&eacute;ticos, fotograf&iacute;as a&eacute;reas, estudios de campo y un experimento en invernadero para examinar el alcance y el mecanismo de la invasi&oacute;n de la variedad no nativa de P. australis en los humedales de Utah. Recolectamos 39 muestras de herbario a lo largo del estado y 225 muestras actuales de los mayores complejos de humedales en el norte de Utah, y las sometimos a un an&aacute;lisis gen&eacute;tico. Todas las muestras recolectadas antes de 1993 y las que se recolectaron fuera de los mayores humedales del norte de Utah, siendo las m&aacute;s recientes del 2001, fueron identificadas como nativas (haplotipos A, B, D y H). Solo 10 (4%) de las muestras actuales fueron nativas, todas de peque&ntilde;os carrizales separados con baja densidad; las restantes fueron nonativas (haplotipo M). Nuestra muestra no nativa m&aacute;s antigua se recolect&oacute; cerca del Gran Lago Salado en 1993. Alrededor del Gran Lago Salado, el cual contiene el 40% de los humedales del estado de Utah, la cubierta de P. australis increment&oacute; del 20% al 56% durante los &uacute;ltimos 27 a&ntilde;os, un aumento que parece atribuirse a la variedad no nativa. En un experimento de invernadero de tres meses, el haplotipo no naivo creci&oacute; m&aacute;s alto, ten&iacute;a m&aacute;s biomasa sobre el nivel de la tierra y una mayor proporci&oacute;n de biomasa sobre el nivel de la tierra por biomasa subterr&aacute;nea que los haplotipos nativos sin importar la disponibilidad de nitr&oacute;geno, f&oacute;sforo o agua. El haplotipo no nativo de P. australis est&aacute; invadiendo r&aacute;pidamente los humedales del norte de Utah. Las &aacute;reas en Utah en donde las variedades nativas permanecen deben ser identificadas y protegidas durante el manejo de carrizos.  相似文献   

5.
In 1979, the walnut spanworm defoliated a 1 ha bitterbrush seed orchard near Nephi, Utah. No seed was produced for two years thereafter due to feeding damage. Life stages were described and illustrated. The female is brachypterous and incapable of flight. First instar larvae readily drop on their silk threads and probably are dispersed by wind. The insect has one annual generation. Moths laid an average of 159 eggs per cluster in April; larvae began to appear in early May and matured by the first week of June. The pupal period extended from June until mid-April. The parasitic bombyliid, Villa faustina (Osten Sacken), was reared from pupae. In April 1980, shrubs contained an estimated average of 1044 eggs each. On 19 May, larvae averaged 1.9 per 7.5 cm of twig and were in the first and second instar. On 20 May the population was controlled by spraying with Sevimol-4. Other potential host plants, as determined from greenhouse tests, are rose, ceanothus, mountain mahogany, serviceberry, and willow.  相似文献   

6.
Productivity and food habits of the Barn Owl ( Tyto alba ) utilizing nest boxes in Juab, Utah, and Salt Lake counties, Utah, During 1979-1984 were examined. Average clutch size was 5.8 eggs for the 6-yr period; mean number fledged was 3.9 young per successful nest. While severe weather during the 1981-82 winter did not result in significant decrease in productivity during the 1982 breeding season, it may have resulted in a significant overproduction of female young. Barn Owls in north central Utah fed almost exclusively on mammalian species, particularly Microtus spp. Difference in clutch size between areas and years may be a response to availability as well as abundance of prey.  相似文献   

7.
An examination of death certificates at the Utah Bureau of Health Statistics from 1900 through 1990 indicates that Utah has a very low incidence of human fatalities due to venomous bites and stings. During this 91-year period, 20 fatalities were recorded from bee (10) or hornet (1) stings, spider bites 94), and rattlesnake bites (5). There were eight additional fatalities during the early part of this century recorded "insect bite," "apparently insect bite," or "unknown agent poisoning," some of which may have included spiders. No deaths were recorded from Gila monster or scorpion evenomizations, although in 1962 one death in San Juan County was recorded as "venom poisoning, unknown agent, possible scorpion." Utah statistics follow the natural pattern, indicating that bee stings cause more fatalities than spider or rattlesnake bites. Raid deaths (within minutes) occurred in the majority of bee sting fatalities, resulting from allergic reactions (anaphylaxis), whereas protracted death times of days or months, resulting from infection, followed most spider or unknown insect bites. Only two spider bite fatalities occurred 1-3 days, suggesting black widow envenomization. Two of the five fatalities from rattlesnake bite resulted from handling the offending snake, one fatality was recorded as a homicide, and one other envenomization occurred in Arizona, with subsequent death in Utah.  相似文献   

8.
Most ornithological literature for Utah reports the status of the Merlin ( Falco columbarius ) as rare or scarce. Only the most recently published checklists (Behle and Perry 1975, Behle et al. 1985) record it as uncommon. Likewise, a 1998 printed checklist (Utah Ornithological Society 1998) list it as uncommon. Also misrepresented in the literature are the status and distribution of the 3 rather distinct subspecies, each of which occupies dissimilar habitats during the breeding season. We made random observations of Merlins in northern Utah beginning in the 1950s and then studied them continuously between 1992 and 1997 in Utah County, Utah. During the 1992-1997 period, we were able to clearly allocate 95 males and 76 females to subspecies, including within our count 58 falcons trapped (some fitted with radio telemetry). The winter habitat in which they occurred was categorized as either urban (mainly dense residential area) or rural (agricultural lands, dairy farms, or scattered homes). There was a statistically significant ( X 2 F. c. columbarius frequenting urban areas 68% of the time, and prairie parkland-breeding F. c. richardsonii frequenting rural habitats 78% of the time.  相似文献   

9.
The Utah taxa of Equisetum were observed with the scanning electron microscope to test for taxonomic significance of stem morphology. The four Utah species of Equisetum were compared. Stem morphology was shown to be taxonomically significant in most cases. The hybrid E. x ferrissii , recognized in the literature as being extant in Utah but heretofore unrecognized in Utah herbaria, was shown to be present in the flora of the state.  相似文献   

10.
Vegetative and atmospheric parameters were evaluated at 16 different nest sites of ring-necked pheasants in Utah County, Utah, to determine which parameters are influential in the nest site selection process. These data indicate that total vegetative ground cover, high amounts of cover immediately surrounding the nest cavity, and drying power of the air are the parameters most influential in nest site selection.  相似文献   

11.
We qualified nest site characteristics, breeding densities, and migratory chronology of Long-billed Curlews at the Great Salt Lake, Utah. The species is apparently declining in Utah, and little is known about their breeding in the eastern Great Basin Desert. This study was designed to provide wildlife biologist with the baseline data useful for their successful management. Curlews arrived in northern Utah in late March and generally departed by mid-August. Nest densities at Great Salt Lake ranged from 0.64 to 2.36 males/km 2 . The habitat at curlew nest sites consisted of significantly shorter vegetation than nearby random locations ( ˉx = 5.7 versus 9.0 cm, respectively; P < .01). Nests tended to be located in small patches of vegetation near barren ground. Maintenance of relatively short vegetation appears to be important in managing curlew habitat. In addition, only 2 of 10 nests we monitored in 1992 were successful, with most lost to mammalian predators. Further research is needed to determine impact of mammalian predators on curlew populations.  相似文献   

12.
The Bonneville cutthroat trout ( Oncorhynchus clarki utah ; BCT) was once abundant throughout the Bonneville Basin. In southwestern Utah, however, only 3 local populations of the subspecies were known to exist in 1977, when conservation efforts to protect and replicate them began. By 1995 remnant populations were known in 6 streams, and replicate populations had been established in an additional 16. Populations of BCT in southwestern Utah streams were survey by electrofishing in 1994 and 1995 to describe the subspecies' status. Estimated densities of age-1 and older BCT ranged from 118 to 546 fish per km. Biomass estimates ranged from 8 to 64 kg per ha. Several age groups of BCT were collected at most locations. Six populations were classified as self-sustaining, 9 as expanding through natural recruitment, 6 as new, and 1 as hybridized. Overall status of BCT in southwestern Utah has improved since 1977, but conservation measures must continue to maintain a positive trend.  相似文献   

13.
Although pinyon-juniper woodland is common throughout most of Utah, it is less so in Utah and Salt Lake valleys. Even so, stands do occur in the valleys and are known to have been there since presettlement times. Three such stands occurring along the eastern sections of the valleys have shown major decreases in area since settlement times, and one has all but disappeared. Their disappearance is attributed to early use for fuel, agricultural, and urbanization purposes. &nbsp;  相似文献   

14.
Named are the following: Astragalus limnocharis Barneby var. tabulaeus Welsh var. nov., from the pass between Boulder Mountain and the Table Cliff Plateau, Garfield County, Utah; A. eremiticus Sheldon var. ampularioides Welsh var. nov. from Washington County, Utah; Lupinus argenteus Pursh var. moabensis Welsh var. nov., from southeastern Utah, validated by inclusion of a Latin diagnosis; Erigeron zothecinus Welsh sp. nov. described from moist alcoves along Lake Powell, eastern Kane County, Utah; Cleomella palmerana Jones var. goodrichii Welsh var. nov. described from Uintah County, Utah; Arabis vivariensis Welsh sp. nov. named from northeastern Uintah County, Utah; Draba kassii Welsh sp. nov. described from material taken in the Deep Creek Mountains, western Tooele County, Utah.  相似文献   

15.
The plant communities and individual plant species in and around a salt playa near Goshen, Utah County, Utah, were studied in relation to gradients for soluble salts, soil moisture, and pH. Forty-eight stands were sampled. Frequency data were taken for all plant species. Soil samples were collected from each site and analyzed to establish the environmental gradients. Results indicate that the vegetational types respond differentially to the three gradients and can be segregated on the basis of one or more of the gradients. The total soluble salts gradient was found to be the most influential of the three sampled. Correlation analysis indicates that 45 percent of the variation in plant diversity can be accounted for by the three gradients. Distributional patterns of individual plant species are strongly influenced by the three gradients. Niche width measurements exhibited no correlation with the measured gradients.  相似文献   

16.
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;} Diel activity and association patterns of white bass ( Morone chrysops ) and carp ( Cyprinus carpio ) in Utah Lake, Utah, were studied over four 24-hr periods during August 1980. Fish were concurrently sampled from two adjacent littoral habitats. Significant differences existed in diel activity patterns in two of three size classes of white bass and in diel association patterns of white bass and carp between the two habitat areas. Differences in habitat structure, and in biological activity between the habitat types, are implicated as the primary determinants of overall diel activity of fish in these littoral areas. &nbsp;&nbsp;  相似文献   

17.
The diatom flora of Beaver Dam Creek, Washington County, Utah, was studied. The study area is in a warm Mojave Desert environment at an elevation between 810 and 850 m. A total of 99 taxa were identified from composite samples taken in the fall, winter, spring, and summer seasons. These taxa are all broadly distributed and no endemic species were encountered. Three new records for the state of Utah were identified: Gomphoneis eriense Skv. & Mayer, Navicula elginensis var. lata. (M. Perag.) Patr., and Nitzschia calida Grun. The most important taxa throughout the study as determined by multiplying percent presence by average relative density (Important Species Index) were Cymbella affinis Kütz., Epithemia sorex Kütz., Navicula veneta Kütz., Nitzschia palea (Kütz.) W. Sm., and Nitzschia microcephala Grun.  相似文献   

18.
The apple maggot, Rhagoletis pomonella (Walsh) is reported from Utah County, Utah, where it has adapted to sour cherries. It has been taken repeatedly from pheromone traps in the vicinity of hawthorn ( Crataegus douglassii ), but there are no Utah data that suggest it has adapted to apples.  相似文献   

19.
Juniperus osteosperma-Pinus monophylla or P. edulis (P-J) woodlands are the most widespread plant community in Zion National Park (ZNP), southwestern Utah. These woodlands dominate nearly half of the park's land area. Our study of this vegetational complex is based on a sample consisting of 115 macroplots (each 0.01 ha in area) objectively distributed across the entire area of ZNP. We recognize 3 subtypes within the P-J complex: Juniperus osteosperma (Utah juniper) alone, juniper with P. monophylla (single-leaf pinyon), and juniper with P. edulis (two-leaf pinyon). The 2 pinyon pines rarely occur together, and thus the foregoing subtypes do not overlap geographically to a significant extent. The first 2 subtypes occur primarily below 1800 m elevation, while the latter is most commonly found above that elevation. Because of the scarcity of sizable expanses (over ~ 10 ha) of well-developed soils in ZNP, the P-J complex occurs primarily on sites where exposed bedrock covers a large portion of the habitat. As a result, over 90% of stands assigned to the P-J complex support less than 50% tree canopy cover (64% have less than 25% tree cover). Shrub cover increases along the woodland successional gradient. Pinyon cover increases faster than juniper cover. Microbiotic soil crust cover is consistently greater in J. osteosperma-P. monophylla woodlands than in J. osteosperma-P. edulis woodlands, but total living cover increases significantly along the successional gradient in both communities. To enhance plant and animal biodiversity, we recommend that pinyon-juniper woodlands of Zion National Park be managed so that late seral stages do not dominate large tracts.  相似文献   

20.
Reported are 158 species of Asilidae (Diptera) in 50 genera from Utah. Keys to subfamilies, genera, and species are given, along with information on seasonal and distributional occurrence in Utah. Seventy-six maps and 56 line drawings show the Utah distribution of each species and illustrate important characters used in the keys. A table summarizes the current status of names used in earlier state lists.  相似文献   

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