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The yellow stingray, Urobatis jamaicensis is the most common elasmobranch in the coastal waters of Southeast Florida. Despite their common occurrence the ecology of yellow stingrays remains poorly understood. In particular, yellow stingray daily movements, space utilization, seasonal distribution and population structure have not been described. This study was conducted to address the lack of knowledge of these fundamental life history parameters and to provide further information on the ecology of U. jamaicensis in coastal waters of Broward County, Florida. The activity patterns and space utilization of U. jamaicensis were assessed by manual tracking with ultrasonic telemetry. Telemetry tracking of 17 stingrays was conducted from January 1998 to September 2001 with data presented on eight individuals tracked for a full diel cycle (24 h). Tracking data was analyzed with the Animal Movement Analysis Extension (AMAE) in Arcview® GIS to provide graphical representation of observed movements within the complex series of reef terraces and hardbottom communities of Broward County. Bottom topography had considerable influence on the space utilization of stingrays and observed movements varied with location in relation to proximity from the reef edge/sand interface. Movement was intermittent throughout the day, but displayed a highly significant increase during the nocturnal and crepuscular phases in comparison to diurnal movements. Nearly all stingrays demonstrated confined movements and indicated strong site fixity, which may imply the existence of home ranging behavior. The 95% (total 24h activity space) and the 50% (core area) Kernel Utilization Distributions (KUD) were constructed to visually display the shape and size of activity spaces. The data was pooled together for the eight individuals tracked for a full diel cycle and divided into four 6-h shifts. Statistically significant larger activity spaces for both the 95% KUD and the 50% KUD were observed during the nocturnal activity phase. Seasonal distribution was assessed to determine animal residency within the study site and ascertain the occurrence and temporal patterns of onshore/offshore movements. Stationary visual fish census techniques (point counts) from several studies conducted in Broward County from January 1998 to December 2003 were combined to determine the level of abundance across three reef tracts, throughout the entire length of the county. Data was tested for monthly and seasonal differences and for variation between reefs. Analysis of seasonal distribution established population residency is year-round with no indication of offshore emigration associated with a temperature preference. Population structure analyses were conducted to determine the sex ratio and size distribution of U. jamaicensis to examine any potential gender segregation or ontogenetic partitioning. The sex ratio was compared for differences monthly, seasonally and between reefs for expected vs. observed frequencies. Only spring observations (March, April, May) evidenced a statistically significant difference from a 1:1 ratio, where females dominated the inshore observations 20F:8M. Average size of both genders was 333mm TL, however, females dominated the larger size classes (>350mm TL). Few neonates were observed during this study with most observations occurring in shallow inshore water (depth), suggesting a nearshore nursery. Increased abundance and presence on the offshore reef among intermediate size classes (250-299mm to 300-349mm) suggests a potential ontogenetic shift to deeper water. Observations on the seasonal patterns of the reproductive condition of female yellow stingrays are also provided.

e sea turtle population utilizing habitats within the Kaho‘olawe Island Reserve (KIR) has gone practically unstudied. This baseline assessment (2002-2005) used a combination of aerial and in-water research methodologies designed in conjunction with recording all incidental sightings and opportunistic reports. In addition, cultural insight, previous studies, literature, and other references were reviewed totaling 708 sightings that provided the subsequent information on the occurrence of turtles within the reserve. Overall, the different research assessment techniques produced similar results, suggesting the validity of the observations. All techniques had their separate merits and played significant roles due to the restrictions imposed on operations within a former military bombing range and the ongoing research activities of the Kaho‘olawe Island Reserve Commission (KIRC) Ocean Resources Management Program. The most superior methodology was the aerial survey for island-wide relative abundances and distributions, but in-water surveys were valuable in assessing turtle population characteristics, especially the fibropapilloma rate and site fidelity. Coastal surveys were done to search for signs of nesting or basking, but none were documented. This study found turtles most commonly swimming individually in clear, shallow water (1-6m depth) coral reef habitats 5-20m from shore. Besides one female hawksbill (Eretmochelys imbricata), all were greens (Chelonia mydas) with no evidence of fibropapillomatosis. Immature turtles predominated and were fairly evenly distributed with some areas of higher density around Kaho‘olawe, namely in the Kākā, Hakioawa and Kealaikahiki regions. Using photo-identification techniques, the strongest example of site fidelity was one particular turtle being resighted three times in the same location, with an 815-day interval between the first and last sighting. It was most common to find the turtles swimming as opposed to resting or foraging. The twenty foraging observations that were made occurred primarily in the Hakioawa and Kākā regions (depth mean=6m, SD=3.8m, range 1-11m). All were seen foraging on turf algae, as the abundance of macroalgae within the KIR was limited. General turtle reactions to our presence were quantified roughly. With humans in the water the majority of the turtles kept a safe distance while exhibiting a slow departure from humans; unless approached closer (by free-diving) which typically caused them to flee. Near equal percentages exhibited flight responses versus toleration of our presence. Only one turtle displayed flipper swiping. During aerial surveys, our helicopter flew at ~31m which did not appear to alter turtle behavior as much as expected. As was the case of turtle reactions to our vessel Hākilo, disturbance was difficult to quantify unambiguously. Some turtles dove abruptly and others appeared to be unaffected by our presence, likely due to other variables unknown to us. Abundance estimates were negatively biased due to availability biases (submerged turtles) and our detection limitations of naturally camouflaged, highly alert animals. Twenty-nine standardized aerial surveys averaged 7.2 turtles (SD=3.4, range 1-14, n=209) per ~60-minute circumnavigation survey yielding a mean density of 0.153 turtles per km (0.248/mile). Nineteen north coast surveys averaged 2.3 turtles (SD=1.76, range 0-6, n=43) per ~20 minute survey, resulting in a mean density of 0.131 turtles per km (0.209/mile). Sixty-seven nearly island-wide snorkel transects yielded a 1.31 turtles/hr mean (transect SD=1.8, range 0-8, n=82). Although effort varied widely, it was most common to incidentally witness one turtle at the surface per (~5-hour) day while different research activities within the reserve were conducted (1.29/day mean, SD=1.26, range 0-6, n=76 field days, n=98 turtles). Exploratory analyses of correction factors for submerged turtles during aerial surveys and the collation of all sightings and references roughly estimate that fewer than 500 turtles inhabit the KIR (although these results should be used cautiously). KIR-specific turtle diving behaviors must be determined to enable reliable correction factors to be applied to density abundance estimates. Although these research results are not directly comparable to other studies within the rest of the Main Hawaiian Islands because this is the first island-wide study, these low numbers suggest a rather insignificant contribution to the extant population of Hawaiian sea turtles. This baseline estimate allows for a) future comparisons using these standardized monitoring protocols, and b) the prioritization of restrictions to important KIR habitats, with implications for management on other islands. As the restoration and management of the KIR continues successfully, this reserve has great potential to host a healthy population of sea turtles that would be able to thrive in a non-anthropogenically stressed environment. Therefore this population and nearshore habitat should continue to be monitored and protected.

In 1984, experimental oil and dispersed oil spill sites were established along the Caribbean coast of Panama, in the Province of Bocas del Toro. Baseline biological, chemical, and physical parameters were collected prior to dosing. Over the following 2.6 years, sites were monitored regularly and results presented in a comprehensive report (Ballou et at., 1987). Ten year follow-up surveys were conducted in 1994 (Dodge et al., 1995). Ten years after dosing, sediment core analysis confirmed the presence of degraded hydrocarbons at both the crude oil and dispersed oil treatment sites. At the whole oil treatment, intertidal regions experienced further mortality in mangroves, while subtidal regions experienced few effects. At the dispersed oil treatment, subtidal corals, significantly impacted following initial treatment, appeared to have recovered. The present study is based on site visits during 2001-02', to the original crude oil, dispersed crude oil, and reference sites established in 1984. Despite the degradation of oil over the past 18 years, sheen is still visible leeching from non-dispersed, crude oil treatment sediments. Previously denuded intertidal mangrove regions currently carry a high sapling density, although recent offsite mangrove mortality may be indicative of continued toxicity and mobility of degraded hydrocarbons. Seagrass growth rates, highly variable at all sites over the duration of monitoring, appear to have been little influence by long-term treatment associated effects, while leaf area parameters at the crude oil treatment have significantly increased relative to the reference site. Sea grasses at the crude oil treatment and dispersed oil treatment both exhibit significantly reduced density relative to the reference site. Within coral zone parameters, current data reveal increased coverage of finger coral (Porites furcata) at the crude oil treatment. Since treatment, percent coverage of P. furcata has grown from 25.0%, in November 1984, to 63.5%, in June 2002. Seagrass and coral parameters are investigated for both between-site differences, and long-term within-site trends. Newly established parameters are investigated to help elucidate possible treatment effects.

As we have become more aware of the value of vegetation in the stabilization of coastal sand dunes, there has been an increasing desire to protect valuable native species in coastal habitats. In Florida, introduced exotic species have tended to crowd and eventually replace native vegetation, resulting in the establishment of monocultures. The Australian pine (Casuarina eguisetifolia) introduced to south Florida in 1898 by Fairchild, has become a weed species on beaches, supressing the native grasses associated with dune formation by its exudation of allelopathic substances. A Casuarina eradication project in Jupiter Island (Martin County), Florida was conducted in an attempt to slow beach erosion by allowing reestablishment of native dune forming grasses. Empirical data was obtained from this area to determine: 1. the effects of the loss of a dominant tree species, 2. the changing of the floristics of the area demonstrating subsequent growth of native vegetation, 3. the species reactions to different degrees of soil's salinity and pH. Throughout the study area (Casuarina stand), the elimination of Casuarina resulted in an immediate growth of four species (Ipomoea pes-caprae –railroad vine, Paspalum vaginatum -salt joint grass, Panicum amarulum -panic grass, Uniola paniculata -sea oats ). I. pes-caprae is an opportunistic species representing an early stage of succession while P. vaginatum, P. amarulum, and U. paniculata are members of the climax community. Diversity indices declined after Casuarina eradication due to the initial rapid growth of I. pes-caprae, however significant linear or exponential growth of the native grasses was observed. It was found that the growth rates vary significantly with season. Away from the immediate shore line, maximum growth for all species occurred from mid to late summer. Highest growth rates for the majority of species occurred on a nearby natural dune (control) site, except for two species (I. pes-caprae and P. vaginatum) which were found to be most abundant throughout the (Casuarina stand) disturbed site.

Ecosystem restoration and management seek to repair, improve, or maintain a suite of desired environmental conditions for a specific ecosystem. However, when working on complex ecosystems, where do you start and how can you tell when you are successful? Forecasting ecological effects of restoration scenarios provides a basis for project evaluation and selection of restoration alternatives. Ecological monitoring is essential for assessing ecosystem condition over time. In an integrated approach to adaptive management a forecasting model simulates system response and is validated by monitoring programs to measure actual system response. Monitoring can then feed back as a passive adaptive management tool to modify restoration or management plans. Directed research driven by uncertainties in models and ecosystem response is an active adaptive management strategy for learning and provides a basis to calibrate models. Since all components of an ecosystem cannot be modeled or monitored effectively, scientists and managers rely heavily on ecological indicators to reveal information about ecosystem status and trends. As a result, modeling and monitoring programs focus on indicators that maximize information on ecosystem patterns and processes while minimizing cost and effort. InSouthwest Florida, conceptual ecological models were constructed to support the framework of an applied science strategy by identifying indicators for estuarine ecosystem assessment and evaluation. Forecasting models were created as a set of stressor response (habitat suitability) models for individual species and incorporated into a spatially explicit decision support system to guide selection of the most beneficial restoration alternative.

Escherichia coli, the preferred bacterial indicator for fecal pollution in fresh waters, does not conform to the concept of an indicator microorganism because it is rapidly killed or inactivated by seawater. This series of papers investigated the value of coliphage, a virus which infects E. coli, as an indicator of pollution in saline waters. In order to be an accurate indicator an organism must (1) be ubiquitous in wastewater, (2) survive and be detectable at least as long as the harmful organisms, and (3) be easy to isolate and identify. A review of the literature determined that coliphage were more resistant than the common bacterial indicators to physico-chemical factors such as inorganic ions, temperature, heavy metals, nutrients, and antibiotics. Coliphage correlation with their bacterial hosts and similarities in behavior to the pathogenic viruses make them both bacterial and viral indicators. Various culture media and host culture strains were investigated for maximum plaque forming unit (pfu) production. Two way analysis of variance showed that selection of a suitable host was of paramount importance. While selection of the culture medium was significant, it was of lesser importance. Host strain ATCC 13706 and tryptic soy agar gave the highest recovery of pfu's. One ml log phase E.coli host culture, five ml of water sample or dilution, and five ml of culture media (maintained at 44.5 C) were combined in a sterile screw cap tube, mixed, poured into a sterile 100 X 15 mm petri dish, and incubated at 35 C. Plaque forming units were counted after 24 hrs. and expressed per 100 ml of sample. The method proved repeatable; the titer of frozen phage aliquots declined slightly over 77 days but, the slope of the trend was not significantly different from zero at the 0.10 level (r = 0.55). These repeated analyses were done with different batches of media and hosts and represent a test of total method repeatability. Bench studies utilizing a decimal dilution series of sewage contaminated freshwater and uncontaminated seawater showed that both coliform and coliphage closely follow a theoretical dilution curve immediately after dilution with seawater. However, coliform bacteria die off at a higher rate than coliphage at higher salinities over time. Field validation studies in fresh and brackish water (<10 >ppt) compared coliphage with total and fecal coliforms (n = 53) and gave correlation coefficients of 0.98 and 0.91 respectively. The regression equation for these samples was: log coliphage = 0.983 (log total coliform) -1.001 The combined total coliform/coliphage relationship at 68 saltwater (>10 ppt) stations yielded a correlation coefficient of 0. 45. Coliphage are a logical choice for a fecal indicator in marine waters since their titers are closely related to total and fecal coliform in freshwater, survive much better than coliforms in seawater, and they can be enumerated by a simple method which is not subject to salinity artifacts. The constant relation of coliphage and coliforms in freshwater indicate a possible link to current water quality standards based on total or fecal coliforms. Since coliphage pfu are a rather constant 8 - 10 % of total coliform cfu in low salinity waters where coliform inactivation is less severe, a coliphage titer of 80 – 100 pfu per 100 ml in seawater may indicate water quality equivalent to that indicated by a coliform count of 1000 cfu per 100 mI. This could aid in the interpretation of coliphage data relative to current coliform-based water quality codes. Monitoring of sanitary water quality in Bell Channel Bay, Bahamas, during repair of a sewer plant showed that following chlorination and diversion of the effluent to a deep well, total coliform declined rapidly below detection limits. Coliphage remained easily detectable ten days later. Two canals and two marinas on Biscayne Bay were assayed for coliphage to compare sanitary water quality related to point and non-point source pollution. The Biscayne Canal was impacted by periodic upstream sewage spills, while the Little River displayed chronic contamination along its length by liveaboard boats or sewer leaks. Coliphage were shown to persist six days longer than coliform after a sewage spil l was tracked in the Canal. The liveaboard Dinner Key marina displayed low-level, spotty contamination with no seasonal pattern. King's Bay marina was free of detectable fecal contamination during the study. The use of coliphage allowed the assessment and monitoring of fecal contamination in marine waters where coliform bacteria were not suitable.

Numerical initial value experiments are used to study time-dependent modifications resulting from small amplitude barotropic and baroclinic perturbations to a steady barotropic inertial gyre in a mid-latitude, circular basin of constant depth. The steady circulation is an exact solution to the quasi-geostrophic potential vorticity equation; it is characterized by a slow westward drift in the interior, and a high-velocity jet which returns the flow along the northern edge of the basin. As control experiments, the evolution of the same perturbations about a state of rest is observed. The redistribution of energy and vorticity is described in detail for the two cases, and particular emphasis is given to the role played by the boundary jet in the transfer of perturbation vorticity from large to small scales. Certain difficulties associated with normal-mode solutions to the control experiments are also discussed.

The following is a study of the regulation of production of a catabolic enzyme, beta-glucosidase, by isolated strains of marine bacteria. Catabolic enzymes transform organic matter to monosaccharides which are utilized as an energy source for growth by bacteria. The bacterial strains were isolated from the Gulf Stream off the coast of Florida, as well as from particulate matter collected from waters adjacent to the Florida coast. The first section describes the preparation of a liquid medium using sterile saltwater supplemented with inorganic nutrients and a carbohydrate component. This medium allowed growth of marine bacteria under carbohydrate-limiting conditions. A solid agar version of the media was also prepared, which allowed isolation of individual colonies of marine bacteria under carbohydrate-limiting conditions. The second section describes analyses of the regulation of beta-glucosidase production by five isolated bacterial strains using methylumbelliferyl-glucopyranoside (MUF-glu) as a model substrate. The beta-glucosidase hydrolysis of MUF-glu to glucose and a highly fluorescing product, methylumbelliferon (MUF ), allowed a measurement of enzyme activity in laboratory cultures. The experiments showed that four of the five bacterial strains isolated could regulate production of beta-glucosidase. When cellobiose, in particular, was the only carbohydrate present, the four strains showing regulatory ability produced elevated levels of enzyme activity. This elevated enzyme activity was not observed when glucose was provided as the only carbohydrate source. The fifth strain showed only low-level enzyme activity in the presence of cellobiose or glucose. This is the first evidence of the regulation of beta-glucosidase activity in particular strains of marine bacteria. Authenticity of beta-glucosidase activity was confirmed with known inhibitors of beta-glucosidase, gluconic acid, and glucose. The enzyme activities of all the isolated strains, measured by hydrolysis of MUF-glu to fluorescent MUF, showed sensitivity to both enzyme inhibitors. The sensitivity was observed as lower MUF production compared to control assay samples with no inhibitor added. The first isolated bacterial strain, from Gulf Stream waters, also showed an ability to repress the production of beta-glucosidase in the presence of glucose. This strain was tested with cylic AMP, known to neutralize glucose repression of beta-galactosidase in E.coli. Cyclic AMP, however, did not neutralize the effect· of glucose on repressing beta-glucosidase activity in the isolated marine bacterium.

A system for obtaining and analyzing sea water samples for dissolved argon, nitrogen and oxygen concentration has been built and used to analyze a suite of twenty-four samples from the Florida Current salinity maximum at 26°5.5' N and 79°57.5' W. Twenty-one samples are between 19 - 22° C, and three lie below that range; twenty-three samples are in the range of 36.30 - 36.45 parts per thousand salinity, and one is below it. All oxygen concentrations are undersaturated, and oxygen saturation decreases with decreasing temperature, in agreement with other studies on the warm water circulation of the Caribbean and the Gulf of Mexico. The mean argon saturation is 102.7%, and the mean nitrogen saturation is 102.5%. The standard deviation of argon and nitrogen saturations is 4.0% and 4.3% respectively. In spite of these large natural deviations, for each gas the per cent saturations within the bottles of a cast are correlated, so that variation from cast means is significantly less than the variation of all samples from the grand mean. Also, certain consecutive cast means are correlated for all three gases. From the structure of these correlations it is concluded that the high salinity water has a gas concentration structure which is characterized by significant deviations from the long term mean. For this study in the Florida Current, a minimum longitudinal scale for inhomogeneity of deviations is ≤20 km; a maximum longitudinal scale for constant value of the deviation is ≥20 km; and the vertical scale can be at least 30 m. The correlation of argon and nitrogen concentration pairs indicates the solution of air in waters very near saturation.