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331.
Five new species of Harasupia in the tribe Teruliini are described and illustrated. These include austini, baja, mexicana, retrorsa , and ungula , all from Mexico. A revised key to 12 known species is also given.  相似文献   
332.
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   
333.
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   
334.
Macroinvertebrate communities were examined on 4 winter dates over a 4-yr period in 2 high-altitude Rocky Mountain streams to document overwintering assemblages potentially experiencing spring acid pulses. Taxa richness values were comparable to other published lists for alpine and montane stream systems despite the fact that most literature reflected summer collections. Mean benthic density ranged from 1406 to 19,734 organisms/m 2 , and drift rates ranged from 0 to 1740 organisms/100 m 3 . Benthic collections showed higher taxa richness than drift collections while the Ephemeroptera and Plecoptera occurred in greater proportions in drift than in benthos. The Nemouridae (Plecoptera), Ephemerellidae and Heptageniidae (Ephemeroptera), Chironomidae (Diptera), and Hydracarina were the numerically dominant taxa in benthic collections. Grazer/scrapers and shredder/detritivores were always the numerically dominant functional feeding groups at all sites, composing 60-90% of the benthos. Predators, constituting approximately 15% of the community, occurred in the same relative proportion at all sites on all dates. Winter macroinvertebrate communities in these low-order, montane streams exhibit high taxonomic richness and benthic densities as great as lower-elevation mountain streams in the West.  相似文献   
335.
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   
336.
A bite by Chiracanthium mildei L. Koch is described.  相似文献   
337.
Yellow pine chipmunks ( Tamias amoenus ) scatter-hoard food during summer and autumn but must form a larder as a winter food source before winter begins. Yellow pine chipmunks do not larder-hoard large quantities of food during the summer, apparently because a summer larder could not be defended from pilferers. We tested the assumption that the rate of pilferage from an unguarded larder would be significantly greater than the rate of pilferage from surface caches (which are also unguarded by yellow pine chipmunks) during the summer and autumn. Buried plastic buckets were used as artificial nests containing larders of 1000 sunflower seeds or 200 Jeffrey pine ( Pinus jeffreyi ) seeds. The pilferage of larder contents was monitored daily and compared to pilferage of surface caches. Animals (yellow pine chipmunks and deer mice, Peromyscus maniculatus ) removed sunflower seeds from caches much faster than from larders, but caches of Jeffrey pine seeds disappeared much more slowly than pine seeds in larders. Further, animals removed pine seeds from larders more quickly than they did sunflower seeds from larders. The difference between seed species was probably because sunflower seeds have much stronger odors, which rodents readily detect, and because chipmunks prefer pine seeds over sunflower seeds. Yellow pine chipmunks must spend a considerable portion of their time foraging for seeds and may not be able to defend a large larder during summer.  相似文献   
338.
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;} In 1973 a timber harvest of ponderosa pine ( Pinus ponderosa ) was conducted in an area southeast of Monticello, Utah, that is inhabited by Abert squirrels ( Sciurus aberti ). Abert squirrel dietary habits, foraging patterns, and population densities were compared in the timber harvest area and in an adjacent nonharvested area. Squirrel feeding patterns and preferences were visually determined by physical evidence of past feeding. Live-trapping and field-marking of animals were used to determine population density and trends in the two areas. Squirrels fed in only 26.3% of sampled plots on the timber harvest areas, while 42.7% of the uncut area plots showed use (P 50 acres) by clear-cut methods commonly employed by management agencies.  相似文献   
339.
Seeds of two halophytes, Atriplex triangularis, which grows in a mesic saline marsh environment, and Atriplex confertifolia, which grows in a xeric desert environment, were analyzed by energy-dispersive X-ray microanalysis for the distribution of elements. The highest concentration of sodium, chlorine, potassium, and calcium was present in seed coats of A. triangularis. All of the elements detected were at low concentrations in the endosperm. Embryos contained the highest amount of phosphorus that is probably associated with organophosphate compounds. Potassium was also high in embryos. The total amount of elements in all regions of A. confertifolia was low as compared to A. triangularis. In a similar pattern sodium, chlorine, potassium, and calcium were the highest in seed coats of A. confertifolia. Elemental concentration was also low in the endosperm. Likewise, the phosphorus level was the highest in the embryo. The results support the concept of elemental compartmentalization in seeds of these halophytes.  相似文献   
340.
Ponderosa pine cones from 10 areas in Arizona were collected prior to natural seed dispersal and dissected to determine the number of sound, hollow, and insect-damaged seeds in each cone. Total and sound seed yields per cone did not vary significantly among areas but did vary significantly among trees within each area. Numbers of hollow and Megastigmus -infested (Hymenoptera: Torymidae) seeds varied significantly among areas and trees within areas. Numbers of sound seed increased significantly with increasing cone length but did not change with increasing numbers of cones per cluster. The percentages of Megastigmus -infested seed did not change significantly with increasing cone length or number of cones per cluster.  相似文献   
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