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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

A Study of the Ring-Necked Pheasant (Phasianus Colchicus Torquatus Gmelin) in Northern Utah

McKean, William T. 01 May 1942 (has links)
Purpose of Study. The ring-necked pheasant (Phasianus colchicus torquatus Gmelin) is well enough known to need no introduction. It is at present undoubtedly the most abundant and most important gallinaceous game bird in northern Utah. Its abundance and its occurrence in agricultural areas has stimulated much general interest. Yet, aside from two food habits studies, both conducted in Utah County, no intensive research has been made into its ecological relationships or its general life history in Utah. In order to formulate sound management plans for the pheasant in Utah, the Utah Cooperative Wildlife Research Unit has felt the need for basic information regarding its mortality phases, movements, food habits, habitat preferences, interspecific relationships, and its effect on cultivated crops and the effect of farm practices upon its numbers and distributions.
232

The spatial distribution of the nests of the black-crowned night heron (Nycticorax nycticorax) and the snowy egret (Leucophoyx thula) in central Utah

Isham, Randall S. 02 August 1974 (has links)
Nests of the Black-crowned Night Heron and the Snowy Egret were examined in five central Utah colonies in 1973 to determine the spatial distribution within the colony. Nest locations of the 1085 nests of the two species were plotted to the nearest foot with an alidade and plane table. Tests of randomness, clump size, association, segregation, and T distribution were utilized. No differences between species were noted for the distance to the nearest and the next nearest nest. The Night Heron nested closer to other Night Herons and more often than did the Snowy Egret which non-significantly selected either species to nest closest. The Snowy Egret nests were 1.7 times higher than the Night Heron nests. Both species nests were aggregated within the colony. The association between the species within the habitat was positive but were segregated within the colony. Nest succession within a colony indicates that the Snowy Egret becomes more selective as time progresses but that the Night Heron remains selective throughout the entire season.
233

Nesting ecology of the double-crested cormorant (Phalacrocorax auritus auritus) on Utah Lake

Mitchell, Ronald M. 01 April 1974 (has links)
Research on the nesting of the Double-crested Cormorant (Phalacrocorax auritus auritus) was undertaken to determine the nesting ecology of the bird on Utah Lake, Utah County, and the possible effects that diking Provo Bay would have on the cormorants breeding there. In 1973, two colonies in Provo Bay were visited weekly to determine laying dates, incubation period, clutch size, and hatching dates. Another colony, located on the dike of the Geneva Steel Reservoir, was visited daily during the spring and summer of 1973. At this colony, egg-laying occurred from 13 April to 17 May. The average clutch size was 3.8, and the egg length and width averaged 60.50 mm x 39.05 mm. An average egg volume of 49.0 cc is first reported for the subspecies. The average period of incubation was 28 days, and 29.5 percent of the eggs hatched, beginning on 20 May and ending 9 June. The young weighed an average of 36 gm at hatching with a beak length of 17 mm and tarsometatarsal length of 11 mm. These increased to 1543 gm, 73 mm, and 58 mm, respectively, in 23 days. The cormorant population on Utah Lake may be severely reduced by the diking of Provo Bay.
234

Small rodent populations and biomass in three sagebrush communities of Rush Valley, Utah

Nichols, David W. 17 February 1972 (has links)
Three desert Artemisia tridentata communities in Rush Valley, Utah were trapped for small rodents during the summer of 1970 in a mark-recapture study. Population densities were estimated using several indices for each population category. Animals were weighed and rodent biomass calculated for each species throughout the summer. Populations, biomass, and other data were then analyzed to gain a better understanding of A. tridentata community types of the Great Basin. Peromyscus maniculatus, Eutamias minimus, and Reithrodontomys megalotis were common to area 1. Peromyscus maniculatus, E. minimus, and Perognathus parvus were common to areas 2 and 3. The peak estimated standing crops were 182.8, 143.1, and 129.7 g/acre for areas 2, 1, and 3 respectively. The population and biomass of area 2 peaked in mid-summer, area 1 in early summer, and area 3 in late summer. Results from a similar study indicate mountain A. tridentata communities may be less productive, in terms of rodent biomass, than desert A. tridentata communities at lower elevations.
235

A study of the channel catfish, ictalurus punctatus (rafinesque), in Mud Lake, Utah

Siewert, Horst Friedrich 01 August 1968 (has links)
From June to November 1967, a study on channel catfish, lctalurus punctatus (Rafinesque), in Mud Lake, Utah Co., Utah was undertaken. The objectives were (I) to estimate if channel catfish are increasing or decreasing in Mud Lake, (2) to estimate the mean size of adult channel catfish in Mud lake, (3) to determine which environmental factors effect the catch of channel catfish, and (4) to determine if the channel catfish in Mud lake are residents year round. A total of 310 mature channel catfish and 920 carp were collected with four hoop nets. Two fingerling were captured by seining. Ratios between carp and channel catfish over a 17 year period had been established which indicated a possible increase in the channel catfish population. With the exception of the fingerIings all channel catfish captured were at least 36.8 cm long with an average of 50.2 cm. A comparison between environmental factors (water temperture, turbidity, water level, and barometric pressure) and the catch showed that only water temperature changes had a statistically significant influence. Large catches during June, July, August, and September were recorded. In later months the numbers of fish captured decreased and no channel catfish could be seen when tho water cleared. It appears that channel catfish utiIize Mud Lake only during the summer.
236

The reproductive biology of the leech Helobdella stagnalis (Linnaeus) in Utah Lake

Tillman, David L. 01 May 1972 (has links)
The reproductive biology of the brooding leech Helobdella stagnalis (Linnaeus) in Utah Lake was studied for an 18 month period from June 1970 to December 1971. In determining the annual reproductive cycle, the number of adult leeches carrying eggs or young were counted at weekly intervals during the reproductive season and monthly during the rest of the year. Gonadal staging data from histological sections were correlated with the field collection data. It was found that two broods of young were produced by the adult animals during the reproductive season. Continuous water temperatures were recorded at the study site throughout the period of this investigation. Temperature was found to have an effect on the rate of gametogenesis, development, and the number of broods produced. The gonads have an off-on type of activity. When the testes are active, the ovaries are dormant and vice-versa.
237

A survey of the helminth parasites and coccidia of cattle and sheep in Utah Valley

Fox, Joseph Carl 13 May 1970 (has links)
A survey of gastro-intestinal parasites in cattle and sheep in Utah Valley was conducted. Cattle in the valley were not seriously parasitized by helminths, whereas sheep usually had heavy helminth infections. Ten genera of helminths and 8 species of coccidia were identified in cattle in the valley, and 14 genera of helminths and 8 species of coccidia were identified in sheep. In conjunction with the survey, meteorologic studies were conducted May through September, 1909, to ascertain the effects which irrigation had upon micro-environments on grass pastures in relation to the development of free-Iiving stages of gastro-intestinal nematodes of ruminants. The effects of irrigation were such that soil moisture remained high throughout the pasture season, and moisture released from the soil to the atmosphere was redeposited as dew almost every night during the study period. Temperature and moisture conditions were conducive for development and survival of gastro-intestinal nematodes during the entire 1969 pasture season.
238

The effect of insect damage on Indian ricegrass (Oryzopsis hymenoides) in western Utah

Guerra, Luis S. 22 December 1972 (has links)
Indian ricegrass at the Desert Range Experiment Station forty-seven miles west of Milford, Utah, is damaged by the larvae of Coenchroa illibella, Diatrae sp. and Typoceris ceraticornis, the latter being the most destructive. The biology of the insects and the extent of damage inflicted are discussed. Uninfested plants produced more new stems than infested plants. Plants having a basal diameter of 4 to 6.9 cm and 7 to 9.9 cm were the most frequently infested and, consequently, the most severely damaged.
239

The snowy egret (Egretta thula Brewsteri) a life history study at Utah Lake with comments on the subspecies status

Gunnell, Gerald Leigh 30 August 1976 (has links)
This study was conducted to augment the limited information available regarding the Snowy Egret in the Utah Lake area of Utah. Field observations included the following: nesting habits; egg and clutch sizes; sexual, defense, and feeding behaviors. Analysis was made of the distinguishing subspecies characteristics (culmen, tarsus, and wing length) of the Snowy Egrets and of the distribution of the birds. Field observations showed that growth measurements of the young varied from 16.75 g at hatching to 260.58 g after 17 days. Culmen and tarsus measurements were 15.41 mm and 14.12 mm to 53.18 mm and 62.18 mm, respectively, after 17 days. The average clutch size was 2.93 eggs per clutch. The average egg measured 43.85 mm by 32.44 mm. Hatching success was 50.85% in the two major periods of hatching noted. The lack of distinct lines of differentiation between existing subspecies leads the author to question the validity of the current subspecies designations.
240

An ecological study of a sphagnum lake in the subalpine forest of the Uinta Mountains of Utah

Stutz, Howard C. 01 June 1951 (has links)
A study was made of the ecology and floristics of a small bog lake referred to as Moss Lake, in the Grandaddy lakes region of the Uinta Mountains , Utah . Three consecutive summers, 1948, 1949, and 1950, were spent in collecting the data presented in this study. Throughout the study the following ecological measurements were made: 1. Water 2. Soil 3. Macroscopic vegetation 4. Plankton 5. Macroscopic animal forms.

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