• The ecology of eulachon (Thaleichthys pacificus) in Twentymile river, Alaska

      Spangler, Elizabeth Ann Kitto (2002-12)
      The ecology of eulachon (Thaleichthys pacificus) was studied at Twentymile River, a tributory of Turnagain Arm located in southcentral Alaska. In 2000 and 2001, we investigated the environmental factors associated with the migration of adult eulachon and downstream drift of larval eulachon. We assessed run timing, freshwater duration, length, weight, age, presence or absence of teeth, fecundity, and gear selectivity for dip and gill nets. Catch per unit effort of migrating adult fish were correlated with water temperature, tide height, river discharge, light intensity, and the density of bald eagles (Haliaeetus leucocephalus). Water temperature, river discharge, tide height, and light intensity were related to downstream drift intensity of larvae. Radio telemetry was used successfully to study the migratrion movements of adult eulachon. Clusters of the upstream limits of migration identified four common spawning areas in both years.
    • Ecology Of Juvenile Pink Salmon In The North Gulf Of Alaska And Prince William Sound

      Boldt, Jennifer Lynn; Haldorson, Lewis J. (2001)
      Increased production of salmon in Alaska has been accompanied by a decrease in average body size and decreased wild stocks, indicating a possible density-dependent response to increases in salmon populations and hatchery releases. Pink salmon have a short two-year life cycle and most post-hatch mortality is thought to occur during their first months at sea; therefore, processes in the early marine residence period may determine abundance. Geographic and seasonal patterns in distribution, growth, and condition of juvenile pink salmon during their first months at sea were examined in Chapter 1. The migration of pink salmon from Prince William Sound (PWS) occurred over several months. Fish lengths, weights, and energy contents varied geographically and seasonally. Pink salmon energy content was highest on the Gulf of Alaska (GOA) shelf in July and August and lowest in PWS in July, indicating that growth conditions were better on the GOA shelf. Spatial and temporal variation in growth and condition is indicative of disparate feeding opportunities for juvenile pink salmon. An unusual aspect of this study was the concurrent collection of zooplankton and fish in PWS and on the GOA shelf. Geographic and seasonal changes in juvenile pink salmon diets were examined during their first six months at sea in Chapter 2. Pink salmon diets varied geographically and seasonally, and prey size increased as fish grew. A unique opportunity existed to compare the energy content of thermally marked hatchery pink salmon to their wild counterparts in PWS (Chapter 3). Fish condition varied geographically, however, there were no differences among hatchery groups and/or wild pink salmon at any one location. This indicates that fish were staying together as a group. In Chapter 4, pink salmon consumption was estimated to represent a small fraction of the production but potentially a large proportion of the available standing stock of zooplankton in PWS. Geographic variations in fish condition, diet, and zooplankton densities were observed in this study. This supports the hypothesis that local processes, including food depletion and/or zooplankton availability are important to juvenile pink salmon.
    • Ecology of mountain sheep: effects of mining and precipitation

      Oehler, Michael William (1999-12)
      We examined effects of mining on mountain sheep (Ovis canadensis nelsoni) in California. Size of home range, forage quality, and diet did not differ between populations in mined and nonmined areas. During summer, we observed the greatest disparity in time spent feeding and diet quality. Because of their dependence on a spring adjacent to the mine, sheep may have spent more time vigilant, and less time feeding. Reducing mining during summer may benefit sheep. We also compared ecology of two female mountain sheep populations from different areas (xeric vs. mesic) in the Mojave Desert. The more xeric Panamint Range was typified by more bare ground, less shrubs, less grass, and larger home ranges than at Old Dad Peak. Females from Old Dad foraged on grasses, whereas those from the Panamints consumed shrubs. We concluded that sheep from the Panamints required larger home ranges because of lower-quantity and quality of forage.
    • Ecology of Prince of Wales spruce grouse

      Nelson, Aleya R. (2010-12)
      Recently, spruce grouse on Prince of Wales Island (POW) in southeast Alaska have been proposed as a separate subspecies. Furthermore, life-history of spruce grouse on POW, which is temperate coastal rainforest, varies sufficiently from birds in mainland areas, mostly boreal forest, to warrant specific management. Therefore, I examined the ecology of spruce grouse on POW to determine how timber harvest influences their survival and habitat selection and ultimately to provide recommendations for their conservation. During 2007-2009, we found that the greatest variation in survival probability was attributed to breeding status. The annual survival of non-breeding birds was 0.72±0.082 (S±) while for breeding birds it was 0.08±0.099. Logging did not adequately predict survival, with no differences among habitats. Conversely, I found differences in selection among habitats. At the watershed scale, spruce grouse preferred unharvested forest. At both watershed and homerange scales, spruce grouse avoided edges and preferred roads. Road-related mortality was the largest known source of death. POW spruce grouse and mainland subspecies exhibit sufficiently different survival rates and habitat preference to warrant specific management. We recommend limited road closures during periods when POW spruce grouse are most vulnerable due to the high rates of mortality associated with this preferred habitat.
    • Ecology Of Reindeer On Hagemeister Island, Alaska

      Stimmelmayr, Raphaela (1994)
      The objective of this study was to investigate and characterize the factors driving the Hagemeister Island reindeer population. A total of 144 reindeer were introduced to Hagemeister Island in 1965 and 1967. The herd initially increased in size to about 1,000 head and then fluctuated around 800 animals. In 1991-1992, a moderate winter die-off of primarily adult bulls ($>$90%) occurred. Adverse snow conditions and poor post rut conditions of bulls appeared to have facilitated the die-off. No conclusive evidence was found that the herd experienced effects of density-dependent food limitation despite poor winter lichen range. In 1993, conception was documented in calves and overall pregnancy rate was approximately 70%. Body size and condition was comparable to other arctic island reindeer herds. This suggests that reindeer on Hagemeister Island do not solely depend on lichen during winter but utilize other forages. <p>
    • Ecology of slimy sculpin (Cottus cognatus) in the Chena River, Alaska

      Sonnichsen, Sandra K. (1981-12)
      The purpose of this study was to gather information on the ecology of slimy sculpin (Cottus cognatus) in the upper Chena River. Three major topics were examined: age and growth, food habits, and habitat preferences. Age of fish was analyzed by length frequency and otoliths. Chena River sculpin were slow growing, reaching a maximum length of 86 mm in 7 years. Stomach contents were examined to determine contribution of different prey to the diet. Chironomids and large mayflies were most important in the diet; electivity indices indicated positive selection for them. Habitat preferences were examined by capturing fish, and measuring habitat variables at the point of capture. These data were analyzed using multiple regressions on principal components. No significant correlation was found between number of sculpin caught and habitat variables of depth, velocity, and substrate type.
    • The ecology of the Arctic char and the dolly varden in the Becharof Lake drainage, Alaska

      Scanlon, Brendan P. (2000-12)
      Becharof Lake is home to both Arctic char (Salvelinus alpinus) and the closely related Dolly Varden (Salvelinus malma), two species known not only to be similar in appearance but also to exhibit similar life histories. The body morphometry, otolith microchemistry, and stomach contents of both species were studied in fish collected from May to September 1998. Morphometric and meristic analysis revealed clear separation in body structure between the two species, as well as potential sub-populations within each species. Otolith microchemistry revealed incidences of anadromy and non-anadromy in both species. Stomach content analysis revealed a broad feeding niche but smaller ranges in food types in individual Arctic char with little seasonal preference, whereas Dolly Varden showed seasonality in food choices. Data suggest that both species can move in and out of the lake system, and that little competition for food or habitat occurs between the two species in the summer months.
    • The ecology of the inshore marine zooplankton of the Chukchi Sea near Point Barrow, Alaska

      Redburn, Douglas Ray (1974-05)
      The temporal variability in abundance, composition, and production of an arctic-marine inshore zooplankton community was investigated near Point Barrow, Alaska from May through August, 1972. Significant temporal differences (P^ < 0.05) in population abundance over the summer were noted for 29 of 30 species. Changes in community composition resulted from the summer intrusion of Bering Sea water into the study area; southern copepods were observed during July and August. This intrusion imposes a temperature regime favorable for the rapid development and high production of meroplankton, particularly barnacle larvae. The meroplankters were largely responsible for creating a more diverse and productive community than that occurring in the epipelagic zone of the central arctic. Extensive recruitment of meroplankton was correlated with periods of high phytoplankton standing stock. Community dry weight ranged from 4 to 41 mg/m , with the maximum occurring under the ice in late June one week after the phytoplankton bloom.
    • The ecology of wolverines in southcentral Alaska

      Gardner, Craig L. (1985-05)
      A study of wolverine (Gulo gulo) ecology was conducted within the upper Susitna Basin in south central Alaska between May 1980 and April 1982. The study was initiated in an attempt to identify potential impacts of hydroelectric development on the wolverine populations. Twelve wolverines (10 males) were fitted with radio transmitters and relocated 153 times. The mean winter and summer home ranges for adult males were 353 km2 and 385 km2, respectively. Adult male home ranges were primarily mutually exclusive, having an average overlap of 4.2% between neighbors. On an annual basis, wolverines appeared to select spruce cover types; this selection was strongest during the winter. The most important foods to wolverines were carrion of ungulates (winter) and ground squirrels (summer). The wolverine population in the Susitna Basin during the study period was not heavily exploited by man and was secure.
    • An econometric analysis of global salmon market prices and its implications for the Alaska wild salmon industry

      Holzinger, Abby C. (2007-05)
      The Alaska wild salmon industry has gone through a period of low prices and changing markets in the past two decades. Average exvessel prices have dropped from $1.46 per pound in 1988 to $0.35 per pound in 2005, due in large part to increased volume of farmed salmon and marine-reared rainbow trout. This thesis examines the potential price and revenue effects from the interaction between wild Alaskan salmon and anticipated production increases of farmed salmon from Chile. To investigate these linkages I developed an international simultaneous equilibrium market model for wild and farmed salmon and marine-reared rainbow trout. While world-wide farmed salmon (and trout) and the various wild Alaskan salmon species are not identical products, they are close substitutes. Changes in the volume of aquaculture production substantially affect the market-clearing prices of wild salmon. This model will then be used to simulate potential changes in Chilean farmed salmon production and Alaska wild salmon production on salmon exvessel prices in Alaska.
    • Economic Analysis Of Alternatives For Railroad Vegetation Control

      Chouinard, Jill Suzanne (1990)
      A survey was distributed to 174 railroads throughout the United States and selected foreign countries. The purpose of the survey was to determine which methods of vegetation control were used along railroad rights-of-way. Cost data were gathered from the railroads responding to the survey and the data were analyzed and compared to an independent cost analysis. Vegetation control by herbicide application, brush cutting, ballast regulating, reballasting, undercutting, and hand clearing were examined. The least expensive alternatives (in average U.S. data base, 1991 dollar base) were vegetation control with a ballast regulator at a cost of $330 per mile, herbicide application at \$485 per mile, and brush cutting with a cost of $554 per mile. An integrated vegetation management program should be developed using a combination of these methods to get the most effective and economic vegetation control. <p>
    • An economic analysis of the market for Alaska wild salmon protein concentrate in China

      Xu, Pei (2004-08)
      The Alaska wild salmon industry has been in economic turmoil for many years. Plagued by increased production of farmed salmon, wholesale and ex-vessel prices for nearly all Alaska wild salmon species and products are at all time lows. The incentive to harvest the flesh of the lower-valued wild salmon species, such as the Alaskan pink and chum salmon, have led to discard problems. There are no seafood products currently made from the late season roe-stripped carcasses and the meat cannot be readily sold due to its perceived poor quality. The fishers and the processors are now faced with a problem of selling wild salmon products of little economic value. This study reports on an effort to investigate a potential Chinese market for Alaskan salmon protein concentrate (a powder product derived from Alaskan wild pink and Chum salmon). Personal surveys of Chinese consumers were conducted in five Chinese cities (Beijing, Tianjin, Baoding, Shijianzhuang, and Wangdu) to determine if this newly developed product would be valued by Chinese consumers. The relative important characteristics of wild salmon protein concentrate made from pink and chum salmon are compared to the existing protein concentrate consumed in China, made from Chinese grass carp, utilizing conjoint analyses.
    • An economic appraisal of hole cleaning using hydraulic horsepower and jet impact force

      Wright, James Alfred (2001-12)
      In today's competitive business environment, reducing operating cost means dollars to the bottom line. One way that a drilling company can reduce operating cost is by optimizing energy use at the mud pumps. The mud pumps are massive pieces of equipment that are the backbone of the cutting's removal system. Optimizing the hydraulics program is one way to reduce mud pump operating cost. Big hydraulics play an important role in the drilling process. The beneficial action of the fluid's cleaning the bottom hole and the bit teeth, and carrying particles into the annulus is well-established. A variety of hydraulic optimization designs are available, however, in this study the efficiency and cost effectiveness of two methods are compared: Jet Impact force and Hydraulic Horsepower. Both methods have a fundamental objective to maximize the available hydraulics to provide optimum cleaning but Jet Impact method optimizes drilling cost better than Hydraulic Horsepower.
    • Economic assessment of Alaska North Slope hydrate-bearing reservoir regional production development schemes

      Nollner, Stephanie P.; Dandekar, Abhijit; Patil, Shirish; Ning, Samson; Khataniar, Santanu (2015)
      The objective of this project was to evaluate the economic feasibility of producing the upper C sand of the Prudhoe Bay Unit L Pad gas-hydrate-bearing reservoir. The analysis is based on numerical modelling of production through depressurization completed in CM G STARS by a fellow UAF graduate student, Jennifer Blake, (2015). A staged field development plan was proposed, and the associated capital and operating costs were estimated using Siemens's Oil and Gas Manager planning software and costing database. An economic assessment was completed, incorporating the most common royalties, the current taxes laws applicable to conventional gas development, and most recent tariff estimates. The degree of vertical heterogeneity, initial average hydrate saturation, well spacing and well type had a significant impact on the regional gas production profiles in terms of cumulative volume produced, and more importantly, the expediency of gas production. The volume that is economically recoverable is highly dependent on how the field is developed. A field that has higher vertical heterogeneity and corresponding lower average initial hydrate saturation is most economically produced using horizontal wells at 160 acre spacing; the acceleration of gas production outweighs the increased drilling costs associated with the longer wells and tighter well spacing. The choice of development scenario does not impact the project economics significantly given a field that has lower vertical heterogeneity; however, development using horizontal wells at 320 acre spacing is marginally more economic than the alternatives. Assuming a Minimum Attractive Rate of Return of 20%, the minimum gas price that would allow economic production of ANS gas hydrates was found to be $29.83 per million British thermal units; this value is contingent on the reservoir having high average initial hydrate saturation and being developed with horizontal wells at 320 acre spacing. A slightly higher gas price of $36.18 per million British thermal units would allow economic production of a reservoir having low average initial hydrate saturation that is developed with horizontal wells at 160 acre spacing.
    • Economic evaluation of gas to liquids (GTL) product transportation through the Trans Alaska Pipeline Systems (TAPS)

      Ejiofor, Nkemakonam (2003-05)
      The Alaska North Slope is a potential candidate for the Gas to Liquid (GTL) technology. With over 38 Tcf of natural gas reserves stranded on the Alaska North Slope, the GTL technology is considered as a possible method of harnessing the abundant resources. GTL fuels are environmentally friendly (sulfur free) with better ignition and burning properties than conventional petroleum products from crude oil. Evaluating the options of transporting GTL products through the existing Trans Alaska Pipeline System (TAPS) together with crude oil either as a blend of crude oil and GTL (commingled) or as alternate slugs of each product (batching) is the main focus of this study. Economic evaluation using Rate of Return analysis to identify the most favorable mode of transportation of the GTL products was performed. Batching, using the modem tracking and sensor techniques was found to be the most economic method yielding the highest return on investment.
    • Economic evaluation of gas to liquids (GTL), crude oil commingled product transportation through the Trans Alaska Pipeline System (TAPS)

      Ibironke, Adejoke Motunrayo; Patil, Shirish L.; Chukwu, Godwin A.; Khataniar, Santanu A.; Reynolds, Douglas B.; Dandekar, Abhijit (2004-12)
      The Alaska North Slope is a potential candidate for the Gas to Liquid (GTL) technology. With over 38 TCF of natural gas reserves stranded on the Alaska North Slope, the GTL technology is considered as a possible method of harnessing the abundant resources. GTL fuels are environmentally friendly (sulfur free) with better ignition and burning properties than conventional petroleum products from crude oil. Economic evaluation using Rate of Return analysis and the Net Present Value (NPV) to identify the most favorable commingled mode for the transportation of the GTL products was performed. The Crystal Ball software was also used to run sensitivity analysis by using the probabilistic approach to give a clear view of the various scenarios on the project economics. Evaluating the options of transporting GTL products as a blend (Commingled) with the Alaska North Slope Crude Oil through the existing Trans-Alaska Pipeline System (TAPS) is the main focus of this study.