Circulation Changes In The Arctic Ocean And Subarctic Seas And Their Connections To The Global Ocean And Climate,
2020
University of South Carolina
Circulation Changes In The Arctic Ocean And Subarctic Seas And Their Connections To The Global Ocean And Climate, Rachel Elizabeth Nichols
Theses and Dissertations
Salinity and freshwater fluxes are important tools for monitoring the amount of freshwater entering and exiting the Arctic Ocean. Satellite-derived salinity provides a way to study surface advective freshwater fluxes; however, sea ice contamination, among others, remains an obstacle in the accuracy and reliability of these measurements. In this study, salinity and surface freshwater fluxes are calculated using NASA’s Soil Moisture Active Passive (SMAP) and the ESA’s Soil Moisture Ocean Salinity (SMOS), Argo, and the European Centre for Medium-Range Weather Forecast’s Ocean Reanalysis version 4 (ORAS4). ORAS4 compares well to Argo in the subarctic seas and is used for comparison …
Performance Evaluation Of Cetacean Species Distribution Models Developed Using Generalized Additive Models And Boosted Regression Trees,
2020
Old Dominion University
Performance Evaluation Of Cetacean Species Distribution Models Developed Using Generalized Additive Models And Boosted Regression Trees, Elizabeth A. Becker, James V. Carretta, Karin A. Forney, Jay Barlow, Stephanie Brodie, Ryan Hoopes, Michael G. Jacox, Sara M. Maxwell, Jessica V. Redfern, Nicholas B. Sisson, Heather Welch, Elliott L. Hazen
Biological Sciences Faculty Publications
Species distribution models (SDMs) are important management tools for highly mobile marine species because they provide spatially and temporally explicit information on animal distribution. Two prevalent modeling frameworks used to develop SDMs for marine species are generalized additive models (GAMs) and boosted regression trees (BRTs), but comparative studies have rarely been conducted; most rely on presence-only data; and few have explored how features such as species distribution characteristics affect model performance. Since the majority of marine species BRTs have been used to predict habitat suitability, we first compared BRTs to GAMs that used presence/absence as the response variable. We then …
Influence Of Stormwater Management On Oxygen Demand And Organic Matter Cycling In Urbanizing Headwater Catchments,
2020
University of South Carolina
Influence Of Stormwater Management On Oxygen Demand And Organic Matter Cycling In Urbanizing Headwater Catchments, Kelly Mccabe
Theses and Dissertations
Excessive organic matter (OM) is driving declining dissolved oxygen (DO) concentrations in coastal ecosystems, worldwide. The quantity, source, and composition of OM transported to coastal ecosystems via stormwater runoff has been altered by land use changes associated with urbanization and subsequent headwater alterations that accompany urban stormwater management. To understand the role of stormwater runoff in the decline of coastal DO, biochemical oxygen demand (BOD) was determined for samples collected during rain events from the outfalls of a variety of stormwater infrastructure with watersheds spanning a range of development. Measurements of particulate and dissolved carbon and nitrogen and chlorophyll-a concentrations …
A Reexamination Of The Freshwater Mussel Community Of The Little Miami River,
2020
Otterbein University
A Reexamination Of The Freshwater Mussel Community Of The Little Miami River, Emily Davis
Undergraduate Honors Thesis Projects
Understanding the changes in biodiversity and local freshwater mussel populations is critical to mitigate the risks to these populations. Freshwater ecosystems continue to degrade rapidly. The freshwater mussel community of the Little Miami River is degraded and has been in decline for many years. The biodiversity contained within freshwater ecosystems is lost at unprecedented rates influenced by human activity. Freshwater mussels play a key role in understanding the effects of human activity on freshwater ecosystems as well as maintaining the health of freshwater habitats. However, they are also sensitive to changes and disturbances, in their ecosystems. This study involved monitoring …
Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean,
2020
The University of Texas Rio Grande Valley
Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney
School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations
We examine the effects of Southern Ocean eddies on phytoplankton cell division rates in a global, multiyear, eddy‐resolving, 3‐D ocean simulation of the Community Earth System Model. We first identify and track eddies in the simulation and validate their distribution and demographics against observed eddy trajectory characteristics. Next, we examine how simulated cyclones and anticyclones differentially modify iron, light, and ultimately population‐specific cell division rates. We use an eddy‐centric, depth‐averaged framework to explicitly examine the dynamics of the phytoplankton population across the entire water column within an eddy. We find that population‐averaged iron availability is elevated in anticyclones throughout the …
New Approaches To Understanding Mjo Dynamics,
2020
University of South Carolina
New Approaches To Understanding Mjo Dynamics, Casey Shoup
Theses and Dissertations
The Madden-Julian Oscillation (MJO) is a highly air-sea coupled phenomenon and is the dominant mode of intraseasonal variability in the tropics. It is easily discernible in satellite-derived sea surface salinity (SSS), which varies as a direct result of MJO precipitation from the convectively active to suppressed phases. Negative (positive) SSS anomalies are associated with the active (suppressed) phase of the MJO. We find that all three available satellite salinity missions (ESA’s Soil Moisture Ocean Salinity (SMOS); NASA’s Aquarius/SAC-D, and NASA’s Soil Moisture Active Passive (SMAP)) are capable of capturing the MJO SSS signal and that the near-equatorial SSS response is …
Diet Analysis Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia,
2020
Old Dominion University
Diet Analysis Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Kristen Marie Volker
Biological Sciences Theses & Dissertations
This study describes the diet of bottlenose dolphins (Tursiops truncatus) stranded in Virginia via stomach content analysis and considers factors such as proportion of numerical abundance and reconstructed mass, frequency of occurrence, average reconstructed prey size, prey diversity and quantity, and otolith degradation code. Fish size was estimated via regression equations established from local fish collected during the study that derive wet weight directly from otolith length or width. Squid size is estimated from previously published equations. Soniferous fishes dominated the diet, especially Atlantic croaker, spot, and seatrout spp., adding evidence to the theory that bottlenose dolphins passively …
Innovative Protection And Conservation Of Coral Reefs In Madagascar,
2020
SIT Study Abroad
Innovative Protection And Conservation Of Coral Reefs In Madagascar, Meghan Parker
Independent Study Project (ISP) Collection
Madagascar is home to approximately 3,450 kilometers of coral reefs, including some of the most biodiverse and valuable marine ecosystems in the Indian Ocean (Webster 2002). This online research project investigates the status of Madagascar’s coral reefs separated by region, threats that are facing the reefs and community-based solutions to protect and conserve the reefs. Conclusions of this online research suggest that most coral reefs in Madagascar are in relatively good health, although looming threats exist from overfishing, increased coastal populations, tourism, and warming waters. Community-based solutions are abundant and have proven effective, and can be implemented nation-wide, personalized to …
Global Patterns In Marine Sediment Carbon Stocks,
2020
Utah State University
Global Patterns In Marine Sediment Carbon Stocks, Trisha B. Atwood, Andrew W. Witt, Juan Mayorga, Edd Hammill, Enric Sala
Ecology Center Publications
To develop more accurate global carbon (C) budgets and to better inform management of human activities in the ocean, we need high-resolution estimates of marine C stocks. Here we quantify global marine sedimentary C stocks at a 1-km resolution, and find that marine sediments store ∼ 3117 (3006–3209) Pg C in the top 1 m (more than twice that of terrestrial soils). Sediments in abyss/basin zones account for 75% of the global marine sediment C stock, and 52% of that stock is within the 200-mile Exclusive Economic Zones of countries. Currently, only ∼2% of sediment C stocks are located in …
In The Face Of Climate Change And Exhaustive Exercise: The Physiological Response Of An Important Recreational Fish Species,
2020
Virginia Institute of Marine Science
In The Face Of Climate Change And Exhaustive Exercise: The Physiological Response Of An Important Recreational Fish Species, Daniel P. Crear, Richard Brill, Lauren M.L. Averilla, Sara C. Meakem, Kevin C. Weng
VIMS Articles
Cobia (Rachycentron canadum) support recreational fisheries along the US mid- and south-Atlantic states and have been recently subjected to increased fishing effort, primarily during their spawning season in coastal habitats where increasing temperatures and expanding hypoxic zones are occurring due to climate change. We therefore undertook a study to quantify the physiological abilities of cobia to withstand increases in temperature and hypoxia, including their ability to recover from exhaustive exercise. Respirometry was conducted on cobia from Chesapeake Bay to determine aerobic scope, critical oxygen saturation, ventilation volume and the time to recover from exhaustive exercise under temperature and …
Deepwater Horizon And The Rise Of The Omics,
2020
Georgia Institute of Technology
Deepwater Horizon And The Rise Of The Omics, Joel E. Kostka, Samantha Joye, Rita Collwell
C-IMAGE Publications
Microbial genomics techniques came of age following the Deepwater Horizon spill, offering researchers unparalleled insights into how ecosystems respond to such environmental disasters.
Microbial Symbionts And Ecological Divergence Of Caribbean Sponges: A New Perspective On An Ancient Association,
2020
Smithsonian Institution; College of Charleston
Microbial Symbionts And Ecological Divergence Of Caribbean Sponges: A New Perspective On An Ancient Association, Christopher Freeman, Cole Easson, Kenan O. Matterson, Robert W. Thacker, David M. Baker, Valerie J. Paul
Marine & Environmental Sciences Faculty Articles
Marine sponges host diverse communities of microbial symbionts that expand the metabolic capabilities of their host, but the abundance and structure of these communities is highly variable across sponge species. Specificity in these interactions may fuel host niche partitioning on crowded coral reefs by allowing individual sponge species to exploit unique sources of carbon and nitrogen, but this hypothesis is yet to be tested. Given the presence of high sponge biomass and the coexistence of diverse sponge species, the Caribbean Sea provides a unique system in which to investigate this hypothesis. To test for ecological divergence among sympatric Caribbean sponges …
Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846,
2020
The University of Texas Rio Grande Valley
Phylogeography Of Acartia Tonsa Dana, 1849 (Calanoida: Copepoda) And Phylogenetic Reconstruction Of The Genus Acartia Dana, 1846, Nicole J. Figueroa, Diego F. Figueroa, David Hicks
School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations
The calanoid copepod, Acartia tonsa Dana, 1849 is one of the most abundant and well-studied estuarian species with a worldwide distribution. In this research, we use the mitochondrial cytochrome oxidase subunit I gene to study the phylogeography of A. tonsa by analyzing sequences from specimens collected in the western Gulf of Mexico (GOM) along with all sequences from previous research. We reconstruct the phylogeny for the genus Acartia Dana, 1846 and highlight numerous potential misidentifications of Acartia species deposited in GenBank. The incorrect taxonomy assigned to some of these sequences results in apparently paraphyletic relationships. This study demonstrates that A. …
Light Organ Photosensitivity In Deep-Sea Shrimp May Suggest A Novel Role In Counterillumination,
2020
Florida International University
Light Organ Photosensitivity In Deep-Sea Shrimp May Suggest A Novel Role In Counterillumination, Heather D. Bracken-Grissom, Danielle M. Deleo, Megan L. Porter, Tom Iwanicki, Jamie E. Sickles, Tamara Frank
Marine & Environmental Sciences Faculty Articles
Extraocular photoreception, the ability to detect and respond to light outside of the eye, has not been previously described in deep-sea invertebrates. Here, we investigate photosensitivity in the bioluminescent light organs (photophores) of deep-sea shrimp, an autogenic system in which the organism possesses the substrates and enzymes to produce light. Through the integration of transcriptomics, in situ hybridization and immunohistochemistry we find evidence for the expression of opsins and phototransduction genes known to play a role in light detection in most animals. Subsequent shipboard light exposure experiments showed ultrastructural changes in the photophore similar to those seen in crustacean eyes, …
Antibiotic Resistance In Marine Microbial Communities Proximal To A Florida Sewage Outfall System,
2020
US Geological Survey
Antibiotic Resistance In Marine Microbial Communities Proximal To A Florida Sewage Outfall System, Dale W. Griffin, Kenneth Banks, Kurtis Gregg, Sarah Shedler, Brian K. Walker
Marine & Environmental Sciences Faculty Articles
Water samples were collected at several wastewater treatment plants in southeast Florida, and water and sediment samples were collected along and around one outfall pipe, as well as along several transects extending both north and south of the respective outfall outlet. Two sets of samples were collected to address potential seasonal differences, including 38 in the wet season (June 2018) and 42 in the dry season (March 2019). Samples were screened for the presence/absence of 15 select antibiotic resistance gene targets using the polymerase chain reaction. A contrast between seasons was found, with a higher frequency of detections occurring in …
Natural Variation And Evolutionary Responses To Climate Change Stressors In Marine Invertebrates,
2020
Louisiana State University and Agricultural and Mechanical College
Natural Variation And Evolutionary Responses To Climate Change Stressors In Marine Invertebrates, Joanna Sarah Griffiths
LSU Doctoral Dissertations
Our rapidly changing climate is putting many species at risk of extinction and there is an urgent need to understand how species will respond to these changes. In this dissertation, I evaluate how three species of marine invertebrates (corals, oysters, and copepods) respond to stressful conditions in their current environments and how plasticity and evolutionary adaptation could alter their response to future climate change stressors. I first employed a space for time study to elucidate population differences in the response of cold-water corals, Balanophyllia elegans, to future ocean acidification. I found evidence that upwelling history (natural low pH exposure) influences …
Effects Of Freshwater Inflow On Nekton Assemblages And Blue Crab Populations In Southeastern Louisiana,
2020
Louisiana State University
Effects Of Freshwater Inflow On Nekton Assemblages And Blue Crab Populations In Southeastern Louisiana, Caleb Benjamin Taylor
LSU Master's Theses
Estuaries along the northern Gulf of Mexico represent some of the most productive ecosystems in the world, providing vital habitat for many recreationally and commercially valuable species, including the blue crab, Callinectes sapidus. The mixing of fresh river and saline ocean water in coastal estuaries contribute to this productivity. Dominated by large river influences and consisting of multiple estuaries, Louisiana contributes the largest commercial fishery in the Gulf of Mexico, and remains, on average, the largest supplier of blue crabs in the nation. However, across southeast Louisiana, freshwater flow is largely dependent on Mississippi River discharge, which is highly …
Evolutionary Traits That Enable Scleractinian Corals To Survive Mass Extinction Events,
2020
University of Haifa
Evolutionary Traits That Enable Scleractinian Corals To Survive Mass Extinction Events, Gal Dishon, Michal Grossowicz, Michael Krom, Gilad Guy, David F. Gruber, Dan Tchernov
Publications and Research
Scleractinian “stony” corals are major habitat engineers, whose skeletons form the framework for the highly diverse, yet increasingly threatened, coral reef ecosystem. Fossil coral skeletons also present a rich record that enables paleontological analysis of coral origins, tracing them back to the Triassic (~241 Myr). While numerous invertebrate lineages were eradicated at the last major mass extinction boundary, the Cretaceous-Tertiary/K-T (66 Myr), a number of Scleractinian corals survived. We review this history and assess traits correlated with K-T mass extinction survival. Disaster-related “survival” traits that emerged from our analysis are: (1) deep water residing (>100 m); (2) cosmopolitan distributions, …
Reproductive Ecology Of Dragonfishes (Stomiiformes: Stomiidae) In The Gulf Of Mexico,
2020
Nova Southeastern University
Reproductive Ecology Of Dragonfishes (Stomiiformes: Stomiidae) In The Gulf Of Mexico, Alex Marks, David Kerstetter, David Wyanski, Tracey Sutton
Marine & Environmental Sciences Faculty Articles
The most abundant fishes on Earth live in the meso- and bathypelagic (deep-pelagic, collectively) zones of the open ocean, where they play a key role in deep-sea food webs by mediating energy flow from surface waters to great depth. Of these fishes, the most speciose taxon is the family Stomiidae (dragonfishes). Despite being the numerically dominant predators of the global mesopelagic zone, stomiid reproductive ecology is poorly known. Research surveys rarely catch larger adults, impeding reproductive ecology studies. Between 2010 and 2011, the Offshore Nekton Sampling and Analysis Program sampled the Gulf of Mexico using a research-sized, opening/closing trawl (10-m …
The Role Of Sexual Reproduction In The Maintenance Of Established Zostera Marina Meadows,
2020
Virginia Institute of Marine Science
The Role Of Sexual Reproduction In The Maintenance Of Established Zostera Marina Meadows, Andrew J. Johnson, R J. Orth, Ken Moore
VIMS Articles
For clonal plants, the role of sexual reproduction in the maintenance of populations can vary widely. Some species are dependent on repeated seedling recruitment. For other species, interactions between adults and seedlings within existing populations can affect seedling survival and limit sexual reproduction in existing populations. Genetic studies of seagrass populations increasingly suggest sexual reproduction is important for the resilience and stability of their populations, but as of yet little observational data support these findings. Because seagrass populations provide important ecosystem services and are threatened with increasing anthropogenic impacts, understanding their reliance on sexual reproduction is evolutionarily and ecologically important. …
