Thesis (Ph.D.)--University of California, San Diego, 2005. / (UnM)AAI3208810. Advisers: Lisa A. Levin; A. Aristides Yayanos. Source: Dissertation Abstracts International, Volume: 67-03, Section: B, page: 1244.

The Grand Banks commercial fishing industry has been faced with several crises in the past decades. These crises have included the major financial crunch and inflation of the late 1970s and early 1980s, as well as the resources collapse of the Northern cod stock and other groundfish stocks in the 1990s followed by the foreign fishing disputes of the mid 1990s. The thesis examines the evolution of the fishing industry in Atlantic Canada during these critical years with focus on the fisheries of the Grand Banks. A linear programming model of the configuration of the Grand Banks commercial fishing fleet is formulated to describe the post 2000 period. The model is driven using the results of an extensive analysis of historical records for this recent period. The model results are validated by comparing them with historical average annual data over the period 2000-2005. The linear programming model is run under several scenarios emulating changes in government policy and economic conditions affecting the harvesting sector. Based on the results, alternative fishing fleet configurations for the Grand Banks fishery are defined to improve the economic viability of the fishing fleet. The model pointed to changes in fleet configuration including a rationalization of the shrimp and crab fleets and a shift to longline vessels with higher-valued product for groundfish harvesting. Once implemented, these suggestions would advance the goals of the new "Oceans to Plate" approach to fisheries management recently announced by Fisheries and Oceans, Canada.

The purpose of this research is to investigate the environmental remediation and energy potential of anaerobic digesters on pig and dairy farms and to demonstrate how incorporating those benefits into a cost-benefit analysis would make biodigester projects more financially feasible. By assigning dollar values to the emissions and water pollution avoided by this technology, I sought to update the traditional cost-benefit analyses (CBAs) to demonstrate that this technology is more widely applicable. The study took place In the Lake Champlain Drainage Basin, USA and the Lake Tai Drainage Basin, China. Dairy and pork production are high density endeavors and produce large quantities of waste which make them ideal candidates for biodigesters. Using standard emissions estimates and gas production rates from past research and from the current Cow Power Program in Vermont, the methane and nitrous oxide emissions averted by adding a biodigester to a particular farm were estimated. Additionally, using past research, the total nitrogen and phosphorous collected by the biodigesters and diverted from becoming classified as non-point source pollution was calculated, valued, and incorporated into a CBA tool. The results from this study show that the incorporation of environmental benefits in a CBA for Green Mountain Dairy increased profitability by 60% and reduced the payback period by two years. Overall, projects that include environmental benefits are 72% more profitable and the payback period is cut in half. Further development of the CBA tool is needed to strengthen results. This study points to the need for more experimental data on the environmental benefits of biodigesters.

Abstract not available.

Abstract not available.

The Bayou LaBranche wetland system, located 22 miles west of New Orleans, LA, received wastewaters from Norco oil refinery from 1920 to 1995. In 1989, the sediment of one of the waterways, Bayou Trepagnier, was designated contaminated with Pb, Cr, Zn, and polycyclic aromatic hydrocarbons. In 1995, the wastewaters were diverted to the Mississippi River, taking with them the main source of fresh water for the system. After seven years of diversion, it is unclear whether contaminants or a loss of significant freshwater input has been more harmful to organisms in this system, or if the organisms have been impacted at all. The stomach contents of two top predators, spotted gar and largemouth bass, were analyzed to determine if there are seasonal variations in dietary preferences and if these variations are due to contaminants in the water and sediment or changes in water quality. The results indicate that the fish collected in Bayou Trepagnier are eating better and are in better condition than those in the other two waterways / acase@tulane.edu

Master of Science / Department of Biology / Craig Paukert / The zebra mussel is an invasive bivalve that was first confirmed in Kansas in 2003, and has decreased zooplankton abundance and altered the aquatic community in other areas where it has invaded. However, little is known about its effects on the aquatic communities of warm-water Great Plains reservoirs. We analyzed zooplankton, benthic macroinvertebrate, and juvenile and small-bodied fish abundance in the littoral zone of an Eastern Kansas reservoir with an established zebra mussel population (El Dorado Reservoir) and a control reservoir without zebra mussels (Melvern Reservoir) for two years pre-zebra mussel invasion (2001-2002) and two years post-invasion (2008-2009). We found no difference in littoral zooplankton abundance between reservoirs across time, but abundance of some macroinvertebrate taxa increased, and abundance of juvenile Lepomis spp. and red shiners decreased in the littoral zone of El Dorado Reservoir in August of the post-zebra mussel invasion period in comparison to the control reservoir. We also analyzed abundance and condition of six adult reservoir fishes in El Dorado Reservoir and three control reservoirs in Eastern Kansas for ten years pre-zebra mussel invasion (1993-2002) and five years post-invasion (2004-2008). Adult white crappie abundance remained constant in El Dorado Reservoir but decreased in the control reservoirs during the post-zebra mussel invasion period, and condition of adult bluegill, white bass, and white crappie decreased in El Dorado Reservoir in the post-zebra mussel invasion period compared to the control reservoirs. Our findings suggest that zebra mussel invasion in El Dorado Reservoir may have affected some benthic macroinvertebrates, juvenile and small-bodied fishes, and adult fishes. We did not find evidence that zebra mussels have had substantial effects on the zooplankton community of El Dorado Reservoir. However, July-August zebra mussel veliger densities in El Dorado Reservoir averaged less than 12 veligers/L in four of the six post-zebra mussel invasion years. Additional research and long-term monitoring of zooplankton, macroinvertebrates, and fishes will be necessary to determine the full effects of zebra mussels on the aquatic communities of warm-water reservoirs throughout North America.

Waterbirds have died of lead poisoning from ingesting lead sinkers in the United States and Europe. Other tackle and litter has also caused injury and mortality to waterbirds. Despite risks posed to waterbirds, no studies of the abundance of tackle or litter in freshwater systems of the United States have been completed. We tested the effectiveness of a metal detector to search for lost and discarded tackle, and developed a technique to correct densities of sinkers. We then quantified tackle and litter abundance at various sites around the United States. Tackle and litter densities varied among sites, but were generally highest in heavily fished areas. Based on the distribution of tackle in light of known mortalities caused by ingestion of sinkers, restrictive management of lead poisoning from sinkers may not be justified. However, lead is a toxic substance and its continued use when nontoxic alternative are available is not logical.

Gila chub (Gila intermedia) were at lower densities in areas of Sabino Creek with green sunfish (Lepomis cyanellus) than areas without sunfish. No young-of-year (YOY) chub were observed in pools where densities of sunfish were reduced by about 90% or in control pools, but YOY chub were abundant in upstream areas without sunfish. The microhabitat selected by YOY chub was nearly identical to that selected by sunfish (7.5 cm, TL). In predation experiments, sunfish (7.5 cm, TL) consumed YOY chub (2.5 cm, TL). The absence of YOY chub in areas with sunfish may, in part, be due to predation by small sunfish. In winter, chub use of microhabitat did not differ in areas with and without sunfish. In summer, chub used faster currents, areas farther from cover and shallower depths in areas with than without sunfish. In summer, niche shifts by chub may be a response to avoid negative interactions with sunfish.

This dissertation explores the creative ways in which particular individuals and the community in general, responds to economic crisis and perceived marginality. It shows how residents of El Golfo de Santa Clara, a small community in the upper Gulf of California, with their meager incomes, fuller utilization of kinship and other social sources, participation in illegal and informal activities, migration, and political participation, are contesting their marginality and resisting the social and economic outcome of state policies in the area. Residents' feeling of frustration and disempowerment increased during the early 1990s. Because of ecological changes and structural adjustment policies the shrimp industry in the Gulf of California collapsed. Household salaries dropped drastically; fishermen were unemployed and families had to look for different strategies to survive. In the midst of the economic crisis residents of El Golfo were told of the decree of a biosphere reserve, which initially had the objective of restricting fishing activity in the area. People's responses involved individual and collective performances and discursive critiques of state authority as represented by the management team of the biosphere reserve. Residents pressed their rights to get involved in the management of the area as well as their rights to get infrastructural services for the town. People's responses show that marginality and poverty had nothing to do with a 'natural' or 'biological' condition, as presented by some earlier anthropological studies of the Mexican countryside, but with a historical economic inequality and the distribution of wealth within the country. The peoples' responses to their economic and political situation underline a critique to their perceived identity as a "rural community" by the managers of the biosphere reserve and authorities that categorized rural people as backward, isolated, uncivilized, and unimportant in the larger social formation. These local responses to the political and economic context suggest that anthropologists should take a more engaged approach in the study of the Mexican countryside.