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The objective of this study is to develop a structural analysis of the relationship.  In addition it investigates the capability of the EU in playing an effective role in the region through strengthening security and political cooperation with the Gulf Cooperation states. As a result of the study it seems that economic integration is the most successful in any regional grouping, especially if this assembly includes similar economies and political structures.  Political and security or military integration between regional groupings prove most complex as these issues represent the identity and sovereignty of the State.  States do not wish to let them to be run by an outside constituency as they symbolize the pride of the state individuality.  This could be seen from the failure of the EU in ratifying the Constitution and Lisbon Treaties.  For the GCC their political cooperation is limited to coordination through their annual Supreme Council Summit, the annual consultation meetings of the heads of states and quadrate Ministerial Council meetings.  In the military integration of the GCC formed forces faced obstacles including limited personnel, the quality of training and standardization of procurement of military weapons. The study concluded that cooperation between the GCC and the EU does not reflect the importance of their economic, historical ties and geographical proximity even though the GCC represents a geostrategic magnitude to the European Union reflected in being a source of energy and a pivotal connection between the three continents (Europe, Africa and Asia).

Gravity and magnetic data from cruises by the R/V Yaquina in 1973 and the R/V Wecoma in 1975 provide new data that make possible the construction of a map of the free-air gravity anomalies at sea and simple Bouguer anomalies on lano in Panama, western Colombia, and the eastern Panama Basin. The gravity measurements and a wide angle reflection line provide data to construct a crustal and subcrustal cross section that starts at 6°N latitude, 80°22.7'W longitude in the Panama Basin and extends 800 km along a line which strikes N19°E across the Gulf of Panama and the Isthmus of Panama to the Colombia Basin. Two important features in the gravity map are the -90 and -100 mgal lows, oriented approximately east-west at 7°N and at 1O°N 1atitude. It is postulated that the southern low reflects a downwarp of the oceanic crust and the northern low reflects a shallow subductjon zone. Filtered magnetic anomalies and seismic refraction measurements support the conclusion that a piece of the oceanic crust which originated at the Nazca-Cocos Rift, forms the upper part of the continental shelf in the Gulf of Panama. The northernmost magnetic anomaly, approximately 50 km south of Panama City, is identified as anomaly number 9 in the geomagnetic scale and indicates 30 million years in age for these rocks which form part of the continental shelf of Panama. The model crustal cross section indicates a maximum thickness for the crust of 25 km for the Isthmus of Panama and a thickness of 17 km for the crust of the Gulf of Panama. The data and the model suggest that both a collision and subduction mechanism may be necessary to explain the tectonics and geology of the area. / Graduation date: 1979

Previous work in the Gulf of Lions, France has suggested that significant amounts of sediment may be escaping through the western part of this tectonically passive margin, despite it being far-removed from the primary sediment source (the Rhone river, ~160 km to the NE). It is hypothesized that the westernmost Cap de Creus canyon is intercepting the regional sediment-transport pathway and directing it offshore, allowing significant sediment export through this area. The overall goal of this project is to determine pathways and causes of sediment movement into Cap de Creus canyon to determine its role in off-shelf sediment export within the Gulf of Lions. Box cores were collected within the canyon and on the adjacent shelf on five cruises (2003-2005). Geochronology (210Pb-derived accumulation rates), grain-size distributions, and sedimentary structures (x-radiography) were analyzed to assess sedimentation patterns. Results indicate two mid-depth shelf depocenters (30-90 m water depth) separated by a zone of bypassing created by current acceleration around a headland. Within the canyon, the northern flank and mid-depth thalweg are modern depocenters of fine-grained sediments. The canyon head and southern flank are considered non-depositional for fine grains, although the head may be accumulating sands. Material enters the canyon from the northern rim (via advection of shelf benthic nepheloid layers), the southern rim (via dense-water cascading off the shelf), and through the canyon head (primarily coarse-grains). Budget calculations indicate that 9-23% of the sediment input to the Gulf is sequestered on the shelf and 1-4% is accumulating in upper Cap de Creus canyon. An ephemeral mud layer within the canyon axis indicates rapid deposition and frequent flushing, suggesting that sediment is moving through the upper canyon. This is also supported by high suspended-sediment concentrations associated with off-shelf dense-water flows. This study suggests that Cap de Creus canyon is an important conduit of sediment past the shelf break and the western margin is a primary location of sediment export from the Gulf of Lions.

The response of the Gulf of Alaska (GOA) circulation to large-scale North Pacific climate variability is explored using three high resolution (15 km) regional ocean model ensembles over the period 1950-2004. On interannual and decadal timescales the mean circulation is strongly modulated by changes in the large scale climate forcing associated with PDO and ENSO. Intensification of the model gyre scale circulation occurs after the 1976-1977 climate shift, as well as during 1965-1970 and 1993-1995. From the model dynamical budgets we find that when the GOA experiences stronger southeasterly winds, typical during the positive phase of the PDO and ENSO, there is net large-scale Ekman convergence in the central and eastern coastal boundary. The geostrophic adjustment to higher sea surface height (SSH) and lower isopycnals lead to stronger cyclonic gyre scale circulation. The opposite situation occurs during stronger northwesterly winds (negative phase of the PDO). Along the eastern basin, interannual changes in the surface winds also modulate the seasonal development of high amplitude anticyclonic eddies (e.g. Hada and Sitka eddies). Large interannual eddy events during winter-spring, are phase-locked with the seasonal cycle. The initial eddy dynamics are consistent with a quasi-linear Rossby wave response to positive SSH anomalies forced by stronger downwelling favorable winds (e.g. southwesterly during El Nio). However, because of the fast growth rate of baroclinic instability and the geographical focusing associated with the coastal geometry, most of the perturbation energy in the Rossby wave is locally trapped until converted into large scale nonlinear coherent eddies. Coastally trapped waves of tropical origin may also contribute to positive SSH anomalies that lead to higher amplitude eddies. However, their presence does not appear essential. The model ensembles, which do not include the effects of equatorial coastally trapped waves, capture the large Hada and Sitka eddy events observed during 1982 and 1997 and explain most of the variance of tidal gauges along the GOA coast. In the western basin, interannual eddy variability located south of the Alaskan Stream is not correlated with large scale forcing and appears to be intrinsic. A comparison of the three model ensembles forced by NCEP winds and a multi-century-long integration forced only with the seasonal cycle, shows that the internal variability alone explains most of the eddy variance. The asymmetry between the eddy forced regime in the eastern basin, and the intrinsic regime in the western basin, has important implications for predicting the GOA response to climate change. Eastern boundary eddies transport important biogeochemical quantities such as iron, oxygen and chlorophyll-a into the gyre interior, therefore having potential upscale effects on the GOA high-nutrient-low-chlorophyll region.

The Kemp’s ridley sea turtle, Lepidochelys kempii, is recovering from devastating declines that reduced nesting activity from a single-day estimate of 10,000- 40,000 females in 1947 to fewer than 300 during all of 1985. Nesting beach monitoring is crucial to estimating population size and reproductive activity, but in-water data are essential for understanding population dynamics and evaluating management strategies. Hook-and-line, stranding, and nesting records, satellite telemetry, and diet analyses were used to characterize ridley population dynamics and movements in the northwestern Gulf of Mexico during 2003-2007. Recreational hook-and-line captures comprised approximately one third of non-nesting encounters along Galveston and Jefferson Counties, Texas. The hook-and-line dataset displayed similar geographical and monthly trends to that of strandings, but was devoid of pelagic-stage, subadult, and adult ridleys. Coastal and bay waters along the upper Texas and western Louisiana coasts were utilized by immature ridleys during warmer months. Nesting occurred along Galveston Island on both armored and unarmored beaches. Inter-nesting females exhibited fidelity to Galveston during nesting season and subsequently migrated to federal waters offshore Louisiana. Crabs were important components of benthic-stage (>25 cm SCL) ridley diet, while worm tubes were targeted by some individuals. Short satellite track durations for immature ridleys precipitated examinations of biofouling, attachment protocols, and turtle excluder device (TED) interactions. Antifouling paints drastically reduced fouling of transmitters. A less-rigid neoprene attachment method was developed to increase transmitter retention on fast-growing juveniles, but further trials are necessary. Transmitters were not damaged or lost during TED trials, but turtle escape times increased when transmitters wedged between TED bars. Projected population growth will increase numbers of Kemp’s ridleys utilizing the Gulf of Mexico and interacting with human activities. Future research should examine year-round distribution and abundance of all life history stages and further characterize recreational hook-and-line capture, nesting activity, movements, and diet. Education efforts targeting the beach-going public, beach residents and workers, and the recreational fishing sector should be employed to promote sea turtle reporting and minimize negative interactions. State and federal managers should examine anthropogenic impacts within the region and determine the need for mitigation and/or regulations to promote continued species recovery.

On Mesoscale Population Study cruises during summers 2004 and 2005 aboard the sailboat Summer Breeze, researchers from the Sperm Whale Seismic Study (SWSS) surveyed for sperm whales along the continental slope of the northern Gulf of Mexico. SWSS scientists tracked 35 groups of whales during these two summers, recording locations where they did and did not encounter whales. Whales were encountered during both summers at approximately the same frequency (19 groups in 38 survey days in 2004; 16 groups in 29 survey days in 2005), but fluke photo-identifications indicated that 85% of individuals encountered during summer 2005 had never been previously identified in the Gulf throughout 10 years of cetacean research. Composition and distribution of these groups also varied between summers. Oceanographic conditions at the edge of the continental shelf differed between 2004 and 2005, which may have modified the usual trophic cascade that begins with near-surface primary production to create local aggregations of prey at the depths where sperm whales forage. Sperm whales are apex, mesopelagic predators, but have been shown to associate with surface primary productivity over large spatial scales and time scales of months to years. The purpose of this thesis was to look for relationships between sperm whale presence and surface oceanography on smaller spatial and shorter temporal scales. Surface ocean color from NASA’s Moderate Imaging Spectroradiometer (MODIS) and surface dynamic height from NASA’s Earth orbital altimeters were evaluated to assess habitat occupied by sperm whales. Passive acoustic monitoring along transect lines for sperm whale clicks permitted determination of sperm whale presence and absence. Sperm whale encounters were in general associated with negative sea surface height and enhanced sea surface chlorophyll (SSC), especially in or near areas where local SSC anomaly was produced by cyclone induced upwelling of nutrients or from coastal water advected off-margin. During summer 2004, SSC was generally high all along the upper continental slope whereas summer 2005 saw relatively low SSC along the upper continental slope. Whales encountered in this study were most highly correlated with SSC two weeks after the initial development of locally highest-SSC anomalies.

Vertical structure of the low frequency horizontal currents at the northern edge of the Loop Current during eddy shedding events is observed using concurrent hydrographic, moored, and satellite altimetry data from 2005. Dynamic modes are calculated at three deep (~3000 m), full water-column moorings in the eastern Gulf of Mexico. Time-series of the barotropic and first two baroclinic modes are found using a least squares minimization that fits theoretically derived modes to observed moored velocity data. EOF analyses show that the majority of observed variance is explained by a surface-trapped mode that is highly coherent with the temporal amplitudes of the first baroclinic mode, and a lower, but significant percentage of variance is captured in bottom-intensified modes. Amplitudes of the second empirical mode indicate that currents are more coherent in the ocean interior approaching the Loop Current, as more variance is explained by this mode at the southernmost mooring near the Loop Current. A dynamic mode decomposition of the horizontal currents reveals that the barotropic and first baroclinic modes exhibit low frequency variability and eddy time scales of 10 – 40 days. Second baroclinic mode amplitudes show higher frequency variability and shorter time scales. A model utility test for the least squares fit of modeled to observed velocity shows that the second baroclinic mode is useful to the statistical model during 50 – 85 % of the mooring deployment, and is particularly necessary to the model when cyclonic features are present in the study area. The importance of the second baroclinic mode to the model increases significantly closer to the Loop Current. High-speed currents associated with the Loop Current and anticyclones stimulate a strong first baroclinic response, but the second baroclinic mode amplitudes are found to be similar in magnitude to the first baroclinic mode amplitudes at times. This happens episodically and could be an indication of higher order dynamics related to frontal eddies or Loop Current eddy shedding.

Previous work in the Gulf of Lions, France has suggested that significant amounts of sediment may be escaping through the western part of this tectonically passive margin, despite it being far-removed from the primary sediment source (the Rhone river, ~160 km to the NE). It is hypothesized that the westernmost Cap de Creus canyon is intercepting the regional sediment-transport pathway and directing it offshore, allowing significant sediment export through this area. The overall goal of this project is to determine pathways and causes of sediment movement into Cap de Creus canyon to determine its role in off-shelf sediment export within the Gulf of Lions. Box cores were collected within the canyon and on the adjacent shelf on five cruises (2003-2005). Geochronology (210Pb-derived accumulation rates), grain-size distributions, and sedimentary structures (x-radiography) were analyzed to assess sedimentation patterns. Results indicate two mid-depth shelf depocenters (30-90 m water depth) separated by a zone of bypassing created by current acceleration around a headland. Within the canyon, the northern flank and mid-depth thalweg are modern depocenters of fine-grained sediments. The canyon head and southern flank are considered non-depositional for fine grains, although the head may be accumulating sands. Material enters the canyon from the northern rim (via advection of shelf benthic nepheloid layers), the southern rim (via dense-water cascading off the shelf), and through the canyon head (primarily coarse-grains). Budget calculations indicate that 9-23% of the sediment input to the Gulf is sequestered on the shelf and 1-4% is accumulating in upper Cap de Creus canyon. An ephemeral mud layer within the canyon axis indicates rapid deposition and frequent flushing, suggesting that sediment is moving through the upper canyon. This is also supported by high suspended-sediment concentrations associated with off-shelf dense-water flows. This study suggests that Cap de Creus canyon is an important conduit of sediment past the shelf break and the western margin is a primary location of sediment export from the Gulf of Lions.

The overall goal of this research was to examine the interactions of adult Amblyomma maculatum Koch, the Gulf Coast tick, with respect to their utilization of hosts and to male-female cross strain interaction. Historical data along with two Petri dish experiments were used to understand male-female interaction in the field, and to determine if the aggregation attachment pheromone (AAP) produced by fed males of varying strains is attractive to geographic specific strains of unfed female ticks. It was hypothesized that questing female Gulf Coast ticks are attracted to fed males and can discriminate between grazing cattle with fed males and those without. Archival control data from ear tag studies conducted in 1985, 1987, and 1991 were analyzed to better understand female Gulf Coast tick behavior in the field relative to fed male tick presence. Females were found primarily on hosts with an abundance of male ticks, leading one to conclude that female ticks are attracted to hosts infested with male ticks. It was also discovered that females were more likely to be found on a host as the number of males on a host increased. A female’s ability to detect hosts parasitized by males likely allows them to feed and mate on-host in a fairly limited period of time. A Petri dish bioassay was used to evaluate female preference to varying geographic strains of fed males. One experiment was designed to determine if a female preferred fed males from her geographically specific strain over other males. A second experiment evaluated female response to a non-specific male in the absence of her geographically specific male. While female responses to fed males regardless of strain were higher than to unfed male control ticks, no statistical differences in female response could be determined. The Petri dish bioassay was determined to be inadequate to test female preference over several populations of pheromone producing males, and a more intensive procedure was proposed.