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Articles 361 - 390 of 498

Full-Text Articles in Oceanography

Spatial Analyses And Repletion Of Gargathy Coastal Lagoon, Loreto Herraiz Gomez Oct 2008

Spatial Analyses And Repletion Of Gargathy Coastal Lagoon, Loreto Herraiz Gomez

OES Theses and Dissertations

Coastal lagoons and bays vary in shape and size in response to antecedent topography, geologic processes and sea level rise. Variations in shape and environmental conditions of coastal basins are believed to influence the distribution of benthic sub-environments and the exchange of water with the ocean and other adjacent coastal systems. Gargathy Inlet and its coastal lagoon vary spatially from the inlet, where the greatest depths are observed, to the mainland, dominated by shallow intertidal areas, colonized by marsh. Hypsographic and hydro-hypsographic analyses of Gargathy's coastal lagoon were the primary techniques applied to understand the relative distribution of the benthic …


An Application For A State Designated, Federally Approved No Discharge Area For Boston Harbor, Ma, City Of Boston Environment Department, City Of Quincy Harbormaster, Urban Harbors Institute, University Of Massachusetts Boston, Charles River Watershed Association Apr 2008

An Application For A State Designated, Federally Approved No Discharge Area For Boston Harbor, Ma, City Of Boston Environment Department, City Of Quincy Harbormaster, Urban Harbors Institute, University Of Massachusetts Boston, Charles River Watershed Association

Urban Harbors Institute Publications

The municipalities surrounding Boston Harbor are requesting that the Commonwealth of Massachusetts designate the waters of Boston Harbor as a No Discharge Area (NDA) pursuant to the Clean Water Act, Section 312(f)(3). An NDA is a body of water in which the discharge of vessel sewage, whether treated or not, is prohibited. The No Discharge Area would be called the Boston Harbor No Discharge Area.

While the waters of Boston Harbor are under the jurisdiction of a number of different municipalities, water quality issues affect the harbor as a whole. Past efforts to clean up the harbor have occurred across …


Hydrodynamic Numerical Ocean Models Support Environmental Studies And Conservation Efforts: From An Arctic Estuary To A Caribbean Coral Reef, Tal Ezer Apr 2008

Hydrodynamic Numerical Ocean Models Support Environmental Studies And Conservation Efforts: From An Arctic Estuary To A Caribbean Coral Reef, Tal Ezer

CCPO Publications

Potential future climate changes, as highlighted recently by the Intergovernmental Panel on Climate Change (IPCC) report, are likely to have different local impacts in different regions of the globe. Oceanic ecosystems may be especially sensitive to large environmental variation, and they are closely connected to physical changes such as temperature, salinity, currents and sea level. Two examples, from very different environments – one in a cold climate and one in a tropical climate, will be discussed here to show how hydrodynamic numerical models are helping to understand physical-biological interactions and potentially help dealing with future climate changes.


Determination Of Photochemically Produced Carbon Dioxide In Seawater, Emily M. White, David J. Kieber, Kenneth Mopper Jan 2008

Determination Of Photochemically Produced Carbon Dioxide In Seawater, Emily M. White, David J. Kieber, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

An analytical system was developed to determine photochemically produced carbon dioxide in marine waters. Our system was designed to measure low levels of carbon dioxide by maintaining a closed system to prevent atmospheric contamination during sample preparation, irradiation, and analysis. To detect low levels of photoproduced carbon dioxide in seawater, background dissolved inorganic carbon (DIC) was removed before irradiation. To strip out DIC, samples were acidified to pH 3.0 (converting DIC to carbon dioxide) and bubbled with low carbon dioxide air. The pH was then readjusted back to the original value, and the resulting low-DIC seawater samples were transferred pneumatically …


Quantifying Vertical Mixing In Estuaries, W. Rockwell Geyer, Malcolm E. Scully, David K. Ralston Jan 2008

Quantifying Vertical Mixing In Estuaries, W. Rockwell Geyer, Malcolm E. Scully, David K. Ralston

CCPO Publications

Estuarine turbulence is notable in that both the dissipation rate and the buoyancy frequency extend to much higher values than in other natural environments. The high dissipation rates lead to a distinct inertial subrange in the velocity and scalar spectra, which can be exploited for quantifying the turbulence quantities. However, high buoyancy frequencies lead to small Ozmidov scales, which require high sampling rates and small spatial aperture to resolve the turbulent fluxes. A set of observations in a highly stratified estuary demonstrate the effectiveness of a vessel-mounted turbulence array for resolving turbulent processes, and for relating the turbulence to the …


Survival Of Eastern Oysters Crassostrea Virginica From Three Lines Following Experimental Challenge With Bacterial Pathogens, Javier Gomez-Leon, Luisa Villamil, Scott A. Salger, Rachel Sallum, Antonio Remacha-Trivino, Dale F. Leavitt, Marta Gomez-Chiarri Jan 2008

Survival Of Eastern Oysters Crassostrea Virginica From Three Lines Following Experimental Challenge With Bacterial Pathogens, Javier Gomez-Leon, Luisa Villamil, Scott A. Salger, Rachel Sallum, Antonio Remacha-Trivino, Dale F. Leavitt, Marta Gomez-Chiarri

Fisheries, Animal and Veterinary Sciences Faculty Publications

Shellfish production is often affected by bacterial pathogens that cause high losses in hatcheries and nurseries. We evaluated the relative survival of larvae and juveniles of 3 Crassostrea virginica oyster lines: (1) GHP, a Rhode Island line; (2) NEHY, a line resistant to dermo and multinucleated sphere X diseases; and (3) FLOWERS, a line resistant to Roseovarius oyster disease, experimental challenge with Vibrio spp. isolates RE22 and RE101, causative agents of bacillary necrosis in Pacific oyster larvae, and the type strain of Roseovarius crassostreae, causative agent of Roseovarius oyster disease. All of the isolates were able to induce significant …


Estimation Of Submarine Groundwater Discharge From Bulk Ground Electrical Conductivity Measurements, Thomas Stieglitz, John Rapaglia, Henry Bokuniewicz Jan 2008

Estimation Of Submarine Groundwater Discharge From Bulk Ground Electrical Conductivity Measurements, Thomas Stieglitz, John Rapaglia, Henry Bokuniewicz

Biology Faculty Publications

The utility of bulk ground conductivity (BGC) measurements in the estimation of submarine groundwater discharge (SGD) was investigated at four sites covering a range of hydrogeological settings, namely Cockburn Sound (Australia); Shelter Island (USA); Ubatuba Bay (Brazil) and Flic-en-Flac Bay (Mauritius). At each of the sites, BGC was surveyed in the intertidal zone, and seepage meters were used for direct measurements of SGD flow rates. In the presence of detectable salinity gradients in the sediment, a negative correlation between SGD and BGC was recorded. The correlation is site-specific and is dependent on both the type of sediment and the mixing …


Ontogenetic Changes In Feeding Ecology And Habitat Of The Damselfish Neoglyphidodon Melas At Lizard Island, Great Barrier Reef, Sai-Wing Chan Oct 2007

Ontogenetic Changes In Feeding Ecology And Habitat Of The Damselfish Neoglyphidodon Melas At Lizard Island, Great Barrier Reef, Sai-Wing Chan

Independent Study Project (ISP) Collection

This study examines ontogenetic shift in habitat and feeding ecology of the black damselfish, Neoglyphidodon melas in three patch reef sites at Lizard Island, Great Barrier Reef. This rarely studied species is unique in its coprophagous relationship with the faeces of the giant clam Tridacna gigas. Distribution and habitat composition between three sites and two reef zones was estimated with 48 Visual Belt and Point Intercept Transects. 80 Focal Animal Studies revealed specific foraging strategies and aggressive behaviours. The timing of this study permitted the inclusion of juvenile recruits resulting in a more complete and comprehensive study across developmental stages. …


To Live With The Sea: Community-Based Management Of Marine Resources In Southwest Madagascar, Hannah Pitt Oct 2007

To Live With The Sea: Community-Based Management Of Marine Resources In Southwest Madagascar, Hannah Pitt

Independent Study Project (ISP) Collection

“God intended us to fish, and we will fish until the end,” the elderly Vezo fisherman explained, shrugging his shoulders as if in resignation to an unavoidable truth (Niry). For a people whose history, culture, and economy have revolved around the sea for generations, the idea of preservation is just not palatable, he seemed to be saying. The momentum of tradition, in other words, cannot be stopped. Yet in 23 Vezo fishing villages in the region of Andavadoaka, along the southwest coast of Madagascar, communities have collectively established seasonal and permanent restrictions on critical fishing grounds that together make up …


Benthic Mapping For Habitat Classification In The Peconic Estuary: Phase I Groundtruth Studies, Robert M. Cerrato, Nicole P. Maher Oct 2007

Benthic Mapping For Habitat Classification In The Peconic Estuary: Phase I Groundtruth Studies, Robert M. Cerrato, Nicole P. Maher

School of Marine & Atmospheric Sciences Faculty Publications

Benthic habitat maps of the estuary seafloor will increase our knowledge of range and variability in benthic habitats, will assist managers in their efforts to protect and/or restore commercially and recreationally important finfish and shellfish, will link land usage (e.g. developed vs. undeveloped areas) and water quality data to benthic habitat quality, and will make it possible to utilize faunal data as a long-term indicator of the overall “health” of the estuary. We are developing benthic habitat maps by combining high-resolution remote sensing techniques with detailed study of the physical and faunal characteristics at point locations in different seafloor environments. …


Distribution Of Ultraviolet-Absorbing Sunscreen Compounds Across The Body Surface Of Two Species Of Scaridae, Elizabeth Cerny-Chipman Oct 2007

Distribution Of Ultraviolet-Absorbing Sunscreen Compounds Across The Body Surface Of Two Species Of Scaridae, Elizabeth Cerny-Chipman

Independent Study Project (ISP) Collection

Ultraviolet radiation has far-reaching effects in marine ecosystems, but many marine organisms have UV-absorbing compounds that protect them from sun-induced damage. The mucus of coral reef fish has been found to contain mycosporine-like amino acids that absorb UV light from 309-360 nm. Using UV spectrophotometry, we examined whether fish are able to allocate these MAA sunscreen compounds to areas of the body that receive the most UV radiation. We compared absorbance spectra of mucus from the body surface of dorsal, ventral, caudal and head areas in two species of Scaridae (Scarus schlegeli and Chlorurus sordidus) from Coral Bay, Western Australia. …


Investigating The Spring Bloom In San Francisco Bay: Links Between Water Chemistry, Metal Cycling, Mercury Speciation, And Phytoplankton Community Composition, Allison C. Luengen Jan 2007

Investigating The Spring Bloom In San Francisco Bay: Links Between Water Chemistry, Metal Cycling, Mercury Speciation, And Phytoplankton Community Composition, Allison C. Luengen

Environmental Science

Investigating the spring bloom in San Francisco Bay: Links between water chemistry, metal cycling, mercury speciation, and phytoplankton community composition This dissertation addresses the relationship between two problems facing estuaries nationwide: nutrient enrichment and metal contamination. The focus is on the southern reach of San Francisco Bay, where high nutrient concentrations can control the magnitude of the predictably occurring spring phytoplankton bloom. The bloom in this study, in spring 2003, was one of the largest blooms on record, exceeding 150 μg L -1 of chlorophyll α. As the bloom grew, diatoms (e.g. Thalassiosira punctigera ) depleted dissolved nutrients from the …


Nitrogen Loading From Wastewater Treatment Plants To Upper Narragansett Bay, Donald Pryor, Emily Saarman, David Murray, Warren Prell Jan 2007

Nitrogen Loading From Wastewater Treatment Plants To Upper Narragansett Bay, Donald Pryor, Emily Saarman, David Murray, Warren Prell

Narragansett Bay Collection

Increasing awareness of low-oxygen conditions in Narragansett Bay, as well as other

symptoms of eutrophication such as macroalgae accumulation, eelgrass failure, and fish

kills, has led to management actions to reduce nitrogen loads to the upper Bay


Nitrogen Loading From Wastewater Treatment Plants To Upper Narragansett Bay, Donald Pryor, Emily Saarman, David Murray, Warren Prell Jan 2007

Nitrogen Loading From Wastewater Treatment Plants To Upper Narragansett Bay, Donald Pryor, Emily Saarman, David Murray, Warren Prell

Narragansett Bay Collection

Increasing awareness of low-oxygen conditions in Narragansett Bay, as well as other

symptoms of eutrophication such as macroalgae accumulation, eelgrass failure, and fish

kills, has led to management actions to reduce nitrogen loads to the upper Bay


Relationships Between Pacific And Atlantic Ocean Sea Surface Temperatures And U.S. Streamflow Variability, Glenn A. Tootle, Thomas C. Piechota Jul 2006

Relationships Between Pacific And Atlantic Ocean Sea Surface Temperatures And U.S. Streamflow Variability, Glenn A. Tootle, Thomas C. Piechota

Civil and Environmental Engineering and Construction Faculty Research

An evaluation of Pacific and Atlantic Ocean sea surface temperatures (SSTs) and continental U.S. streamflow was performed to identify coupled regions of SST and continental U.S. streamflow variability. Both SSTs and streamflow displayed temporal variability when applying the singular value decomposition (SVD) statistical method. Initially, an extended temporal evaluation was performed using the entire period of record (i.e., all years from 1951 to 2002). This was followed by an interdecadal-temporal evaluation for the Pacific (Atlantic) Ocean based on the phase of the Pacific Decadal Oscillation (PDO) (Atlantic Multidecadal Oscillation (AMO)). Finally, an extended temporal evaluation was performed using detrended SST …


Human Development And Resources Use In The Coastal Zone: Influences On Human Health, Robert E. Bowen, Anamarija Frankic, Mary E. Davis Jun 2006

Human Development And Resources Use In The Coastal Zone: Influences On Human Health, Robert E. Bowen, Anamarija Frankic, Mary E. Davis

Environmental, Earth, and Ocean Sciences Faculty Publication Series

Coastal watersheds and nearshore marine areas are the most valuable and dynamic places on Earth. Human population growth is great in these regions, which are home to some of the most sensitive habitats in the world. Coastal areas provide more than half of the overall service value derived from the global environment (Costanza et al., 1997). Natural (e.g., hurricanes and tsunamis) and human pressures on this environment require it to constantly adjust. More than any other area, the global coast has defined the progress of human culture and continues to be a singular influence in how humans connect to the …


Sea Urchin Predation In Misali Island Marine Park, Nicole Esclamado Apr 2006

Sea Urchin Predation In Misali Island Marine Park, Nicole Esclamado

Independent Study Project (ISP) Collection

The populations of sea urchins and their main predators, triggerfish (Balistidae), wrasses (Labridae) and emperors (Lethrinidae), were studied in the extractive and non-extractive zones of the Misali Island Marine Conservation Area in order to (1) evaluate the applicability of a sea urchin-sea urchin predator model developed in Kenya’s fringing reefs, (2) gain baseline data on Misali’s coral reef, and (3) evaluate the recovery status of the protected zone. This study revealed the predictive power of the sea urchin-sea urchin predator model for the reef ecosystem of Misali Island. As expected, a decline in sea urchin predators as a gross trophic …


Factors Affecting The Distribution And Health Of The Intertidal Coral Goniastrea Aspera On The Reef Flat In Geoffrey Bay, Magnetic Island, Julia Smith Apr 2006

Factors Affecting The Distribution And Health Of The Intertidal Coral Goniastrea Aspera On The Reef Flat In Geoffrey Bay, Magnetic Island, Julia Smith

Independent Study Project (ISP) Collection

The intertidal zone can be a harsh environment, presenting many challenges to the organisms inhabiting it. Given its dynamic nature, it is surprising that it is sometimes able to sustain systems as delicate and sensitive as coral reefs. Many organisms have adapted to life on the intertidal reef flat, and one of the most prominent on the northeastern coast of Australia is the massive coral Goniastrea aspera. The mechanisms driving the distribution of this species are not entirely understood; this study investigated the potential role of microhabitat, as well as that of actual physical characteristics of the colonies, in the …


Hydrographic Observations During The 2002 Ioc Contaminant Baseline Survey In The Western Pacific Ocean, C. I. Measures, Greg A. Cutter, W. M. Landing, R. T. Powell Mar 2006

Hydrographic Observations During The 2002 Ioc Contaminant Baseline Survey In The Western Pacific Ocean, C. I. Measures, Greg A. Cutter, W. M. Landing, R. T. Powell

OES Faculty Publications

The 2002 IOC Contaminant Baseline Survey in the western Pacific Ocean was the fourth in a series of cruises intended to establish the contemporary concentrations of trace elements and other materials in the major water masses of the ocean and to illuminate the pathways by which materials delivered to the surface ocean are incorporated in the subsurface waters. The expedition occupied 9 vertical profile stations encompassing the subtropical and subarctic gyre of the western North Pacific. In addition, underway surface water samples were collected during transits between the stations. This paper uses the temperature, salinity, nutrient, oxygen, and chlorophyll data …


Iron In Ice Cores From Law Dome: A Record Of Atmospheric Iron Deposition For Maritime East Antarctica During The Holocene And Last Glacial Maximum, Ross Edwards, Peter N. Sedwick, Vin Morgan, Claude Boutron Jan 2006

Iron In Ice Cores From Law Dome: A Record Of Atmospheric Iron Deposition For Maritime East Antarctica During The Holocene And Last Glacial Maximum, Ross Edwards, Peter N. Sedwick, Vin Morgan, Claude Boutron

OES Faculty Publications

Total dissolvable iron (TDFe) was measured in sections of ice cores recovered from Law Dome on the coast of Wilkes Land, East Antarctica. These samples include ice dating from the Last Glacial Maximum (LGM), the Last Deglaciation, and the early and mid Holocene as well as samples from the Anthropocene that have been dated with seasonal to annual resolution. Combining our TDFe concentration data with estimates of the ice accumulation rate, we estimate the atmospheric iron deposition for Law Dome and the adjacent Southern Ocean during these periods. Our results indicate that the atmospheric iron deposition flux to this region …


Coupled Oceanic-Atmospheric Variability And U.S. Streamflow, Glenn A. Tootle, Thomas C. Piechota, Ashok Singh Dec 2005

Coupled Oceanic-Atmospheric Variability And U.S. Streamflow, Glenn A. Tootle, Thomas C. Piechota, Ashok Singh

Civil and Environmental Engineering and Construction Faculty Research

A study of the influence of interdecadal, decadal, and interannual oceanic-atmospheric influences on streamflow in the United States is presented. Unimpaired streamflow was identified for 639 stations in the United States for the period 1951–2002. The phases (cold/negative or warm/positive) of Pacific Ocean (El Niño–Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO)) and Atlantic Ocean (Atlantic Multidecadal Oscillation (AMO) and North Atlantic Oscillation (NAO)) oceanic-atmospheric influences were identified for the year prior to the streamflow year (i.e., long lead time). Statistical significance testing of streamflow, based on the interdecadal, decadal, and interannual oceanic-atmospheric phase (warm/positive or cold/negative), was performed by …


Burial Of Terrestrial Organic Matter In Marine Sediments: A Re-Assessment, David J. Burdige Jan 2005

Burial Of Terrestrial Organic Matter In Marine Sediments: A Re-Assessment, David J. Burdige

OES Faculty Publications

Calculations based on recent observations indicate that approximately one third of the organic matter presently being buried in marine sediments may be of terrestrial origin, with the majority of this terrestrial organic matter (TOM) burial occurring in muddy, deltaic sediments. These calculations further suggest that the remineralization of terrestrial organic matter in the oceans is also much less efficient than that of marine organic matter. These two underappreciated observations have important implications in terms of our understanding of the controls on the global carbon cycle. From a paleoceanographic perspective, the results presented here also suggest that changes in TOM burial …


The Effect Of Submarine Canyon Width And Stratification On Coastal Circulation And Across Shelf Exchange, Kyung-Hoon Hyun Jul 2004

The Effect Of Submarine Canyon Width And Stratification On Coastal Circulation And Across Shelf Exchange, Kyung-Hoon Hyun

OES Theses and Dissertations

A 3-D ocean circulation model is used to investigate the effect of the width of a submarine canyon and stratification on adjacent coastal circulation and across shelf exchange. Upwelling winds for 20 d drive circulation over six canyons of varying widths (8–60 km), two escarpments to represent infinitely wide canyons, and a generic shelf-slope without a canyon. Also six stratifications whose first internal Rossby radii (a) range over 2–18 km were applied to two canyons (20 and 40 km) to see the effect of stratification. All simulations adjust to the canyon after 5 days spinup and reach an …


Feasibility Of Mapping Benthic Biotopes In The Hudson River, Nicole P. Maher, Robert M. Cerrato Mar 2004

Feasibility Of Mapping Benthic Biotopes In The Hudson River, Nicole P. Maher, Robert M. Cerrato

School of Marine & Atmospheric Sciences Faculty Publications

Successful management of aquatic resources requires comprehensive maps that identify the spatial distribution and extent of potentially vulnerable habitats and their resident biota (e.g., essential fish habitat). We illustrate a technique that describes submerged landscapes not only in terms of geophysical properties, but also in terms of the resident biotic communities. Biological community distribution was highly correlated with the geophysical provinces initially identified by Bell et al. (2000). However, fewer groups of stations (created mainly by combining provinces) explained almost as much of the variation in benthic community structure and was a better description of the major biotopes in this …


Estimation Of Primary Production And Carbon Flux In Antarctic Coastal Waters: A Modeling Study, Hae-Cheol Kim Jan 2004

Estimation Of Primary Production And Carbon Flux In Antarctic Coastal Waters: A Modeling Study, Hae-Cheol Kim

OES Theses and Dissertations

This study presents results from models that are designed to simulate the underwater light field, to simulate phytoplankton primary production, and to estimate the fate of phytoplankton carbon in continental shelf waters of the west Antarctic Peninsula (WAP) and Ross Sea. Simulation of the underwater light field required derivation of new coefficient sets for power function-type cloud cover correction algorithms, which were found to be influenced by multiple reflections between the bottom of clouds and the surface. The coefficient sets indicate that the spectral effect of clouds on the properties of the surface irradiance was spectrally-neutral for wavelengths greater than …


Light Dependence Of Selenium Uptake By Phytoplankton And Implications For Predicting Selenium Incorporation Into Food Webs, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter, Lynda S. Cutter, Brian Cole Jan 2004

Light Dependence Of Selenium Uptake By Phytoplankton And Implications For Predicting Selenium Incorporation Into Food Webs, Stephen B. Baines, Nicholas S. Fisher, Martina A. Doblin, Gregory A. Cutter, Lynda S. Cutter, Brian Cole

OES Faculty Publications

The potentially toxic element selenium is first concentrated from solution to a large but highly variable degree by algae and bacteria before being passed on to consumers. The large loads of abiotic and detrital suspended particles often present in rivers and estuaries may obscure spatial and temporal patterns in Se concentrations at the base of the food web. We used radiotracers to estimate uptake of both selenite (Se(IV)) and C by intact plankton communities at two sites in the Sacramento/San Joaquin River Delta. Our goals were to determine (1) whether C and Se(IV) uptake were coupled, (2) the role of …


Black Carbon In Estuarine And Coastal Ocean Dissolved Organic Matter, Antonio Mannino, H. Rodger Harvey Jan 2004

Black Carbon In Estuarine And Coastal Ocean Dissolved Organic Matter, Antonio Mannino, H. Rodger Harvey

OES Faculty Publications

We measured black carbon (BC) in ultrafiltered, high-molecular weight dissolved organic matter (UDOM) in surface waters of Delaware Bay, Chesapeake Bay, and the adjacent Atlantic Ocean (U.S.A.) to investigate the importance of riverine and estuarine dissolved organic matter (DOM) as a source of BC to the ocean. BC was 5-72% of UDOM-C (27 ± 17%), which corresponds to 8.9 ± 6.5% of dissolved organic carbon (DOC), with higher values in the heavily urbanized midbay region of the Delaware Estuary and lower yields in the river and coastal ocean. The spatial and seasonal distributions of BC along the salinity gradient of …


Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi Jan 2004

Age And Growth Of Scotia Sea Icefish, Chaenocephalus Aceratus, From The South Shetland Islands, M. La Mesa, J. Ashford, E. Larson, M. Vacchi

OES Faculty Publications

Samples of Chaenocephalus aceratus (Lönnberg) were collected during a trawl survey carried out around the South Shetland Islands in January–February 2002. Fish were caught by commercial bottom trawl fishing down to 500 m depth, using a stratified randomized sampling design. As observed in other recent surveys within the same area, C. aceratus represented one of the predominant species. Overall, 357 specimens ranging from 13 and 67 cm (TL) were selected for the present study. Ages were estimated by counting annuli present in the sagittal otoliths, exposed by grinding and polishing along their sagittal plane. To estimate the precision of age …


Advection, Krill, And Antarctic Marine Ecosystems, Eileen E. Hofmann, Eugene J. Murphy Jan 2004

Advection, Krill, And Antarctic Marine Ecosystems, Eileen E. Hofmann, Eugene J. Murphy

CCPO Publications

Advective processes are recognized as being important in structuring and maintaining marine ecosystems. In the Southern Ocean advective effects are perhaps most clearly observed because the Antarctic Circumpolar Current (ACC) provides a connection between most parts of the system, including open ocean and continental shelf regions. The ACC also provides a mechanism for large-scale transport of plankton, such as Antarctic krill (Euphousia superba Dana), which is an important component of the Southern Ocean food web. This overview provides a summary of recent observational and modelling results that consider the importance of advection to the Southern Ocean ecosystem and, in particular, …


Experimental Investigation Of Elemental Incorporation In The Otoliths Of Larval And Juvenile Fish: Implications For Use As Environmental Recorders, Gretchen Bath Martin Jan 2003

Experimental Investigation Of Elemental Incorporation In The Otoliths Of Larval And Juvenile Fish: Implications For Use As Environmental Recorders, Gretchen Bath Martin

Biological Sciences Theses & Dissertations

Innovative techniques for discerning fish stocks, identifying nursery habitats, locating spawning sites, tracing larval transport pathways, and quantifying the degree of population connectivity are required to meet the goals of sustainable management of marine capture fisheries. One of the most promising techniques is the use of elemental signatures in fish otoliths (ear stones), which record valuable life history data and serve as the link between fish and their environment. To validate the assumption that otolith elemental composition is a function of water elemental concentrations, and to address the possible effects of external variables such as temperature and salinity, the composition …