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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.
11

The Feeding Value of Certain Duck Food Plants of the Bear River Migratory Bird Refuge As Determined By Chemical Analysis

Christensen, Dale Clair 01 May 1938 (has links)
Chemically analyzed a variety of plants from the Bear River Migratory Bird Refuge at intervals throughout the growing season to determine the following constituents: carbohydrates, nitrogen, crude fat, crude fiber, total ash, and the following ash constituents: Ca, P, Mg, Na, K, and Cl.
12

Muskrat and Waterfowl Production and Harvest on Dingle Swamp, Bear Lake County, Idaho

Reeves, Henry M. 01 May 1954 (has links)
The Dingle Swamp Wildlife Study was initiated in 1952. The main objective of the project was determining means for increasing wildlife production and utilization of the Dingle Swamp near Bear Lake. The investigation was a general survey of muskrat and waterfowl populations and environments.
13

Overwinter Mortality of Trout in Temple Fork of the Logan River

Cerven, Daniel Richard 01 May 1973 (has links)
The objectives of this study were to determine the mortality rates of trout in Temple Fork of the Logan River during the winter of 1970-1971 and to identify factors related to trout mortality. Trout in seven 100-m sections of the 7 3-km stream were sampled by electroshocking in October, December, February, and April. Captured trout were weighed measured and tagged or fin-clipped. Scale samples were taken for age determinations and the fish were returned to the creek. Water temperature, snow cover, and anchor ice were monitored. Three species of trout were found in Temple Fork: brown, rainbow, and cutthroat trout. Daily instantaneous mortality rates were calculated for both marked trout and estimated numbers in the stream.
14

Resource Partitioning Among Brown Bears at Brooks River in Katmai National Park and Preserve, Alaska

Olson, Tamara L. 01 May 1993 (has links)
A quantitative study of the behavior of brown bears (Ursus arctos) was undertaken in areas of differing human activity at Brooks River in Katmai National Park and Preserve, 1988-1990. The research was conducted to determine whether the activity of any particular classes of bears using the river were differentially affected by human activity, activity of conspecifics, or availability of salmon. Approximately 1643 hours of systematic observation were recorded, 781 between June 26 and July 29 and 862 hours between August 26 and October 12 of all three years. Comparisons of fish capture rates by bears and distributions of bear use among observation zones were made by grouping individually identified bears according to both their age-sex class and tolerance of people (habituation). Differences in distributions of use among age-sex classes were apparent only during June-July; during that time subadults and females with young favored use of the river below Brooks Falls to a greater degree than other bears. Fish capture rates recorded during July 1990 showed a more than three-fold increase over those observed 1988-1989. The apparent increase in fish availability to bears that year was accompanied by the only observed differences in fish capture rates among age-sex classes. During July 1990 salmon availability in the observation zones near Brooks Camp increased significantly over the previous two years; habituated bears (tolerant of people at <50 >m) showed nearly three times as much use of those zones as in 1988-1989. In contrast, nonhabituated bears (61.5%-76.3% of all adult bears observed among observation years and seasons) showed minimal use of these areas despite the high availability of salmon. During the fall of each year fish capture rates appeared highest in the observation zones near Brooks Camp. Habituated bears used these zones significantly more than did nonhabituated bears, and overall rates of river use were higher for habituated than nonhabituated bears. Depending on their habituation class, females with young showed distinctly different use patterns through the fall season and across observation zones. All nonhabituated females with young (50.0% of females with young of known habituation class) favored use of the observation zone nearest Brooks Camp, and their activity was highest late in the season when human activity was minimal. The implications of patterns of use by age-sex class and degree of habituation to people are discussed.
15

Models for Estimating Energy and Protein Utilization for Feeds

Wardeh, Muhammad Fadel 01 May 1981 (has links)
Data on the proximate nutrient content of feedstuffs , digestibility and energy utilization available from the International Feedstuffs Institute (Utah State University) were used to develop mathematical models for estimating energy and protein utilization of five classes of feedstuffs for various kinds of animals. Classes of feedstuffs were subdivided into more related subclasses. Furthermore, data from all feeds were pooled together then subgrouped into more related subgroups in an attempt to gain high precision in prediction of digestible proximate nutrients and TDN from a single chemical entity by the use of simple regression models (Y = bo + b1x1). Digestible percentages (Y) of crude protein , ether extract, crude fiber and nitrogen free extract were highly correlated with their proximate contents (Xs) of most classes, subclasses and subgroups of feedstuffs for various kinds of animals. However, the use of linear multiple regression equation resulted in more precision in estimating each digestible nutrient (Y) from proximate analysis (Xl ; CP%, Xz ; EE% , x3 ; CF% and X4 ; NFE%) of the different classes of feedstuffs for various kinds of animals. Prediction of digestible proximate nutrients made it possible to calculate Tn~ by the conventional equation: TDN ; DCP% + DCF% + DNFE% + 2.25 x DEE%. And to calculate digestible energy (DE) from the following equation : DE(Mcal/kg); 5.72 (DCP%) + 9.5 (DEE%)+ 4.79 (DCF%) + 4. 03 (NFE%)/100 TDN, DE and ME (Ys) were highly correlated with the digestible proximate nutrients (X1 ; DCP%, x2 ; DEE% , X3 ; DCF% and X4 = DNFE%) and with proximate analysis (upon the use of multiple regression models). However, TDN, DE and ME (Ys) were not predictable with high precision from any one single chemical entity (Xs) in most cases of the different classes of feedstuffs for various kinds of animals. DE (Y) was highly correlated with TDN values (X), and ME (Y) was highly correlated with DE and TDN (Xs) values of t he different classes of feedstuffs for various kinds of animals. The inclusion of physical descriptions (qualitative factors) of feedstuffs along with chemical analysis (quantitative factors) gave promising results predicting TDN content of feedstuffs. MEn and NEP for poultry were highly correlated with proximate analysis of the different classes of feedstuffs. NEP was also estimated with high precision from MEn. However, both MEn and NEP were not highly associated with single chemical entities. The dissertation contains an extensive literature review on systems of evaluating nutritive value, and factors affecting digestibility of feedstuffs. This dissertation also contains numerous equations which predict each digestible nutrient from its proximate content and from proximate analysis; TDN, DE and ME from each proximate nutrient, digestible proximate nutrients and proximate analysis; DE and~~ from TDN; and ME from DE contents of different classes of feedstuffs for various kinds of animals. Moreover, there are complex equations to predict TDN from proximate analysis and their interactions and from proximate analysis plus physical descriptions of feedstuffs for various kinds of animals.
16

Influence of Breed Type, Milk Production Potential and Cow Size Upon Maintenance Requirements

Kennedy, Jacqueline Lee 01 May 1984 (has links)
Two biological types of cows, straig htbred Herefords (HxH) and Simmental-Hereford cros ses (SxH), of similar body condition were individually fed over a 10 week period to compare the biological types for maintenance and to determine the influence of milk production potential and of size. Cows were nonlactating and in the last part of the first trimester of pregnancy. During the first 5 weeks of the feeding experiment, one-half of each type was fed 75% of est imated maintenance while the other half was fed 125% of estimated maintenance. During the last 5 weeks of the experiment those fed at 75% of maintenance in the first 5 weeks were now fed 140% of maintenance while those fed 125% of maintenance in the first 5 weeks were now fed 65% of maintenance. Maintenance requirement was estimated by two methods. The first method, regression of gain or loss on energy intake, showed a higher, but non-significant maintenance requirement for SxH (137.5 vs. 128.3 kcal ME/kg.75/day for SxH and HxH, respectively). The second method, which involved estimating maintenance as the residual when energy associated with gain or loss in weight was subtracted or added to the total energy intake, gave maintenance values of 117.6 and 145.9 kcal ME/kg.75/day for HxH and SxH cows, respectively. A comparison of gain in weight for amount of energy consumed, for cows having equal energy intake per unit of metabolic size, indicated that HxH cows used energy more efficiently than SxH cows (P<.20). The SxH cows were higher in milk production but when the effects of biological type were removed milk production potential was not significant. Size had a linear, negative effect upon maintenance requirement even though weight was expressed as wkg.75. When the .75 exponent was replaced by either .7, .73, or .78, size was still significant and negative.
17

Range Beef Cattle Productivity in Southern Utah

Maiga, Mouslim A. 01 May 1984 (has links)
Twenty-six range beef cattle ranches in southern Utah were surveyed by personal interview to obtain production data. The data were used to characterize the level of production efficiency in terms of calving rate, weaning rate, weaning weight, and net weaning weight in these operations; and to identify factors associated with differences in productivity. The data revealed that productive efficiency was generally lower than the potential. Mean calving rate of cows exposed for breeding was 83.4%. Stepwise regression involving calf death losses at or shortly after birth and heifer replacement rate accounted for 98.3% of the variance in calving rate. Calving rate differed (p< .05) with cow condition and herd type. Crossbred herds averaged the highest calving rate (90.3±6.3) compared to the straight bred herds (76.1±9 .9 ). Mean weaning rate was 80.1%. The difference of 3.2% between calving rate and weaning rate reflects pre-weaning death losses. Mean calving date, age of replacement heifer at first breeding and calving assistance influenced weaning rate but only for 31.5% of the total variance of weaning rate (p < .25). Crossbred herds had higher weaning rates (86.7±7.3) vs. straightbred herds (72.6±12.5). Also cows in moderate condition during lactation had higher weaning rates (83.0±10.2) compared to cows in borderline condition (76.2±12.9). An average weaning weight of 20 1.6 kgs was obtained by the herds surveyed. Weaning age (p < .05) herd size, (p < .175) and herd type (p < .25) were important source of variation in weaning weight. Mean net weaning weight of calves (pounds of calf weaned per cow exposed) was 178 kgs. Mean calving date and cow condition affected (p < .05) net weaning weights. Crossbred herds averaged net calf weaning weight 70.1 lbs higher than straightbred herds. Positive correlations (.18 < r < .32) were observed between cow condition, range condition, and calving rate, weaning rate, weaning weight and net weaning weight. Correlations between calving rate, weaning rate, length of breeding season, number of cows per bull and heifer replacement were negative (-.25 < r < -.08). A flowchart of a range beef cattle production system was conceptualized. The chart may be used to examine management alternatives.
18

Influence of Disturbance on Greater Sage-Grouse Habitat Selection in Southern Utah

Hansen, Erica P. 01 May 2016 (has links)
The greater sage-grouse (Centrocercus urophasianus; sage-grouse) is a species of conservation concern that occupies sagebrush-dominated (Artemisia spp.) landscapes across the western United States and southern Canada. The U. S. Fish and Wildlife Service (USFWS) reviewed the status of the sage-grouse in September 2015 and determined that it did not warrant protection under the Endangered Species Act due to collaborative efforts between numerous public and private stakeholders. However, this decision hinged on federal and state commitments to continue science-based management of sagebrush habitats. As human development increases across the west, there is an increasing need for understanding the impacts of disturbance on sage-grouse. Filling this knowledge gap is important because it will allow us to predict how sage-grouse populations may respond to changes in the future. I assessed how two types of disturbance (wildfire and transmission line construction) influenced habitat use of a population of sage-grouse in southern Utah. I deployed Global Positioning System (GPS) transmitters on 26 (21 male and 5 female) sage-grouse in the Bald Hills Sage-Grouse Management Area in 2014 and 2015 to record what habitat sage-grouse were using during the summer and winter seasons. I compared these used locations to habitat that was seasonally available to the birds using resource selection functions. My models showed that in the summer, birds showed preference for areas burned and reclaimed within the last 10 years. I suggest that this may be occurring because the birds are seeking out vegetation that was seeded by the Bureau of Land Management (BLM) during wildfire reclamation. In the winter, my models showed an overall 3% decrease in predicted probability of use for winter habitat in the vicinity of the transmission line corridor, but this change did not immediately result in increased avoidance by sage-grouse when comparing spatial distributions for sage-grouse locations within winter habitat near the transmission line. I suggest that this is because the new transmission line was paired with a preexisting line which was already avoided by sage-grouse. However, the construction of the new line could have long-term consequences outside the two year scope of my study. These impacts could be delayed because sage-grouse are strongly tied to historic habitats and may not change habitat use immediately in spite of landscape changes. Additionally, the presence of the new line could cause indirect landscape changes which may only manifest over longer time periods such as increasing human activity in the area or changing the distribution of avian predators of sage-grouse that use the transmission line for perching. I recommend continued monitoring of sage-grouse in the area to determine if any changes in habitat use manifest in future years.
19

Selected Parameters of Reproduction in Rambouillet and St. Croix Ewes

Evans, Ronald Cole 01 May 1987 (has links)
Experiments were conducted to determine the genetic reproductive potential of Rambouillet and St. Croix ewes . Ovulation rate (monthly) and estrus (daily) were observed for two years on 10 ewes of each breed to establish seasonal patterns . Both breeds demonstrated seasonal anestrus from May through July. Ovulation rates reached 2.0 or greater for both breeds during September to November, and decreased to 1.25 by March. Breeding groups for St. Croix and Rambouillet ewes were bred each February and August for five years to establish lambing performance at six month intervals. Age at first lambing was earlier for St. Croix than Rambouillet (89% vs 0.0% lambing at 12 months of age). Both breed and age influenced lambing rate. Fifty-two of 108 (48%) lambings from mature St. Croix ewes occurred at six month intervals, compared to 1 of 85 for Rambouillet ( 1.2%}. No Rambouillet under 36 months lambed at 6 month interval, while 8 of 61, 12 month St. Croix ewes lambed at a 6 month interval (13.1%). Mature St. Croix ewes that lambed at six month intervals produced 3.44 lambs per year, compared to 2.03 for ewes that lambed once a year. Parturition interval was 262 days for mature and 302 days for 24 month and younger St. Croix ewes on a six month lambing schedule. Parturition interval for mature Rambouillets was 355 days. Blood samples were taken twice weekly and serum progesterone measured by RIA in 17 St. Croix and four Rambouillet ewes that lambed during the normal breeding season, to determine occurrence of postpartum ovulation. Average days to first postpartum ovulation was 35.8 and 35.6 for St. Croix and Rambouillet, respectively. Thirteen of seven teen (76.5%) St. Croix ewes showed estrus with first ovulation, while none of the Rambouillet showed estrus with first or second postpartum ovulation. The shortened postpartum period for St. Croix compared to Rambouillet (40 .2 vs > 70 days) was a result of estrus accompanying the first or second postpartum ovulation.
20

Foraging Behavior and Habitat Use Patterns of Brown Bears (Ursus arctos) in Relation to Human Activity and Salmon Abundance on a Coastal Alaskan Salmon Stream

Crupi, Anthony P. 01 May 2003 (has links)
Over the past decade, demand for recreation has increased as part of Alaska's doubling growth in tourism. Along the Chilkoot River, near Haines, fishing and bear viewing have become increasingly popular. I investigated the ecological and behavioral interactions there between two brown bears, salmon, and humans between 2000 and 2002. My objectives were to: (1) determine if specific human activities differentially influenced bear activity and foraging behavior, (2) identify temporal and spatial habitat use patterns, (3) evaluate brown bear response to natural and human disturbances and quantify related flight distances, (4) investigate changes in bear foraging behaviors in response to prey abundance and human activity to find if bears selectively forage to maximize energy intake, and (5) assess the role of individual tolerance for human proximity in relation to specific foraging behaviors. Evidence clearly indicated that temporal and spatial brown bear activity patterns were influenced by human activity. Bears were most active and spent the longest periods of time fishing when the numbers of anglers and vehicles were below threshold levels. Adult female bears disproportionately preferred (73%) non-roaded riparian habitat, while subadults were less selective. I classified over 1000 disturbance responses and found human activity accounted for 46% of bear departures with a mean flight response distance of 97 meters. When humans were either absent or at distances greater than or equal to 100 meters from bear activity, bears captured fish at higher rates, captured 2.65 times as many fish, and caught greater proportions of live fish (71%). The greatest predictors of capture rate were the time of day when bears fished, the proximity of human activity, and the individual's tolerance level. Bear tolerance for human proximity helped explain variation in capture rates, foraging bout lengths, and total salmon captured. This suggests nutritional rewards for bears adapting to human disturbance. These analyses depict clear relationships with simple interpretation of the dynamic relationships between people, bears, and their environment. With improved understanding of the Chilkoot River's natural resources, managers can work to reduce bear-human conflicts and plan for continued growth in tourism and recreation.

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