Marine Biology Commons^™

Reaching 1.5 And 2.0 ◦C Global Surface Temperature Targets Using Stratospheric Aerosol Geoengineering, Simone Tilmes, Douglas G. Macmartin, Jan T. M. Lenaerts, Leo Van Kampenhout, Laura Muntjewerf, Lili Xia, Cheryl S. Harrison, Kristen M. Krumhardt, Michael J. Mills, Ben Kravitz, Alan Robock

School of Earth, Environmental, & Marine Sciences Faculty Publications

A new set of stratospheric aerosol geoengineering (SAG) model experiments has been performed with Community Earth System Model version 2 (CESM2) with the Whole Atmosphere Community Climate Model (WACCM6) that are based on the Coupled Model Intercomparison Project phase 6 (CMIP6) overshoot scenario (SSP5-34-OS) as a baseline scenario to limit global warming to 1.5 or 2.0 ◦C above 1850–1900 conditions. The overshoot scenario allows us to applying a peak-shaving scenario that reduces the needed duration and amount of SAG application compared to a high forcing scenario. In addition, a feedback algorithm identifies the needed amount of sulfur dioxide injections in …

Taxonomic Richness And Diversity Of Larval Fish Assemblages In The Oceanic Gulf Of Mexico: Links To Oceanographic Conditions, Corinne R. Meinert, Kimberly Clausen-Sparks, Maëlle Cornic, Tracey Sutton, Jay R. Rooker

Marine & Environmental Sciences Faculty Articles

Biodiversity enhances the productivity and stability of marine ecosystems and provides important ecosystem services. The aim of this study was to characterize larval fish assemblages in pelagic waters of the northern Gulf of Mexico (NGoM) and identify oceanographic conditions associated with areas of increased taxonomic richness (T ) and Shannon diversity (H’). Summer ichthyoplankton surveys were conducted in the NGoM in 2015 and 2016 using neuston net (surface layer; upper 1 m) and oblique bongo net (mixed layer; 0–100 m) tows. Over 17,000 fish larvae were collected over the two-year study, and 99 families of fish larvae were present. Catch …

Fish Community Composition And Structure Near A Freshwater River Diversion In Southeastern Louisiana, Rachel L. Snider

LSU Master's Theses

Gulf of Mexico estuaries, particularly in Louisiana, are among the world’s most productive, with landings of commercially- and recreationally-important species exceeding all other contiguous US states. Coastal wetlands are disappearing at an alarming rate because they have been impounded from Mississippi River water and sediment. Although controversial, one proposed solution is to re-route the Mississippi River through diversions and siphons to supply the freshwater and sediments necessary to rebuild vanishing wetlands, particularly in Barataria Bay and Breton Sound, LA. This strategy is one approach outlined in the Louisiana Coastal Master Plan. This project aimed to describe the composition and structure …

Opinion: Midwater Ecosystems Must Be Considered When Evaluating Environmental Risks Of Deep-Sea Mining, Jeffrey C. Drazen, Craig R. Smith, Kristina Gjerde, Steven Haddock, Glenn S. Carter, Anela Choy, Malcolm R. Clark, Pierre Dutrieux, Erica Goetze, Chris Hauton, Mariko Hatta, Julian Koslow, Astrid Brigitta Leitner, Aude Pacini, Jessica Nicole Perelman, Thomas Peacock, Tracey Sutton, Les Watling, Hiroyuki Yamamoto

Marine & Environmental Sciences Faculty Articles

No abstract provided.

Morphological And Molecular Characterizationof A New Species Of Black Coral From Elvers Bank, North-Western Gulf Of Mexico (Cnidaria:Anthozoa: Hexacorallia: Antipatharia:Aphanipathidae: Distichopathes), Dennis M. Opresko, Samantha L. Goldman, Raven Johnson, Katherine Parra, Marissa Nuttall, G.P. Schmahl, Mercer R. Brugler

Publications and Research

The continental shelf edge of the NW Gulf of Mexico supports dozens of reefs and banks, including the West and East Flower Garden Banks (FGB) and Stetson Bank that comprise the Flower Garden Banks National Marine Sanctuary (FGBNMS). Discovered by fishermen in the early 1900s, the FGBs are named after the colourful corals, sponges and algae that dominate the region. The reefs and banks are the surface expression of underlying salt domes and provide important habitat for mesophotic coral ecosystems (MCE) and deep coral communities to 300 m depth. Since 2001, FGBNMS research teams have utilized remotely operated vehicles (e.g. …

Reproductive Effort Of Montastraea Cavernosa Across Depth In The Context Of Both Climate Change Refugia And Emergent Disease, Jeanne Bloomberg

LSU Master's Theses

As coral populations on shallow reefs decline globally, mesophotic coral ecosystems (MCE) have been suggested as potential coral refugia in the face of climate changes, leading to the development of a comprehensive deep reef refugia hypothesis. The current study assesses the climate and disease refuge potential of MCEs in the U.S. Virgin Islands (USVI) for the gonochoric, broadcast-spawning species Montastraea cavernosa. Polyp, population, and total habitat fecundities were estimated across the species’ depth range, and changes to population oocyte production over time due to recent ecosystem disturbances were considered. The number of gonads producing oocytes in each polyp and oocyte …

Quantifying Spatiotemporal Variability In Zooplankton Dynamics In The Gulf Of Mexico With A Physical-Biogeochemical Model, Taylor A. Shropshire, Steven L. Morey, Eric P. Chassignet, Alexandra Bozec, Victoria J. Coles, Michael R. Landry, Rasmus Swalethorp, Glenn Zapfe, Michael R. Stukel

Faculty Publications

© 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Zooplankton play an important role in global biogeochemistry, and their secondary production supports valuable fisheries of the world's oceans. Currently, zooplankton standing stocks cannot be estimated using remote sensing techniques. Hence, coupled physical–biogeochemical models (PBMs) provide an important tool for studying zooplankton on regional and global scales. However, evaluating the accuracy of zooplankton biomass estimates from PBMs has been a major challenge due to sparse observations. In this study, we configure a PBM for the Gulf of Mexico (GoM) from 1993 to 2012 and validate the model …

Insights To Gray Seal (Halichoerus Grypus) Foraging Ecology From Stable Isotope And Dna Metabarcoding Analyses, Keith Michael Hernandez

LSU Doctoral Dissertations

The enactment of wide-ranging conservation laws in the United States enabled the recovery of many marine mammal species. However, as many species have surpassed predicted recovery goals, there is an increasing number of marine mammal-human interactions. For example, in the northeast US, the recovery of gray seals (Halichoerus grypus atlantica), coupled with declines in commercially important fishery species, has prompted discussions of revised management, and potentially lethal control measures. Much of this concern stems from seal-fisheries interactions, which necessitates an understanding of seal diets and foraging ecology. However, existing research is out of date and reliant primarily on …

Cultivating Cooperatives: Benefits And Challenges Of Co-Ops And Recommendations For Maine’S Emerging Aquaculture Industries, Phoebe Walsh

All Theses And Dissertations

Two emerging Maine industries, kelp (Saccharina latissimi and Saccharina angustissima) and Atlantic sea scallop (Placopecten magellanicus) aquaculture, have enormous market, environmental, and social potential but are faced with challenges of small scale and limited operations, inadequate infrastructure, market visibility, and limited expertise. Because many industries, particularly the dairy industry, have benefited from the use of cooperatives (co-ops) to aggregate an extremely perishable product, quickly process and effectively market and distribute, this research explores the cooperative model as a potential tool for the nascent scallop and kelp industries. Aquaculture co-ops are new in Maine. The first, the …

Temporal And Stoichiometric Patterns Of Algal Stimulation Of Litter-Associated Heterotrophic Microbial Activity, Steven N. Francoeur, Robert K. Neely, Savannah Underwood, Kevin A. Kuehn

Faculty Publications

1. Periphyton communities associated with submerged plant detritus contain interacting autotrophic and heterotrophic microbes, and are sites of extracellular enzymatic activity. The strength and nature of these interactions might be expected to change over time as microbial communities develop on plant litter. Microbial interactions and enzymatic activity can be altered by nutrient availability, suggesting that litter stoichiometry could also affect these phenomena.
2. We grew wetland plants under ambient and nutrient‐enriched conditions to generate plant litter of differing nutrient content. In two experiments, we investigated: (1) the influence of algal photosynthesis on fungal and bacterial production and the activities of four extracellular …

Analysis Of The Facilitative Interaction Between Batis Maritima And Avicennia Germinans As A Mangrove Restoration Strategy, Javier R. Navarro

Theses and Dissertations

The multiple experiments conducted in an Avicennia germinans forest in Laguna Vista, TX was focused on determining if facilitation theory could explain the behavior observed between the herbaceous halophyte Batis maritima and A. germinans. I hypnotized that a positive interaction exists but through which mechanisms of facilitation I did not know. The overarching theme of the study is the presence or absence of B. maritima. Facilitation theory tells us that positive interactions are most often found under stressful conditions such as those on the coastal tidal flat of the Laguna Madre. Locally B. maritima has been found to …

Spatiotemporal Dynamics Of Benthic Microalgae In South Carolina Shelf Sediments, Sarah N. Zaunbrecher

Theses and Dissertations

Benthic microalgae (BMA) play essential roles in food webs and regulating nutrient exchange at the sediment-water interface in continental shelf ecosystems. However, shelf BMA are not widely studied due to the difficulties sampling the upper few millimeters of shelf sediments. A few published studies have highlighted the high spatiotemporal distribution of BMA, but detailed explanations for this known variability are limited. The objectives of this study were to quantify BMA biomass variability on scales of cm to km and relate these measurements to in situ nutrient concentrations, sediment grain size, in situ irradiance, depth, and other environmental factors. Water and …

The Expanded Footprint Of The Deepwater Horizon Oil Spill In The Gulf Of Mexico Deep-Sea Benthos, Michael G. Reuscher, Jeffrey G. Baguley, Paul A. Montagna

C-IMAGE Publications

The 2010 Deepwater Horizon blowout off the coast of Louisiana caused the largest marine oil spill on record. Samples were collected 2–3 months after the Macondo well was capped to assess damage to macrofauna and meiofauna communities. An earlier analysis of 58 stations demonstrated severe and moderate damage to an area of 148 km². An additional 58 archived stations have been analyzed to enhance the resolution of that assessment and determine if impacts occurred further afield. Impacts included high levels of total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAH) in the sediment, low diversity, low evenness, and …

Combined And Independent Effects On Hypoxia And Tributylin On Mrna Expression And Physiology Of The Eastern Oyster (Crassostrea Virginica), Ann Fairly Barnett, James H. Gledhill, Robert J. Griffitt, Marc Slattery, Deborah J. Gochfeld, Kristine L. Willett

Faculty Publications

Oyster reefs are vital to estuarine health, but they experience multiple stressors and globally declining populations. This study examined effects of hypoxia and tributyltin (TBT) on adult Eastern oysters (Crassostrea virginica) exposed either in the laboratory or the field following a natural hypoxic event. In the laboratory, oysters were exposed to either hypoxia followed by a recovery period, or to hypoxia combined with TBT. mRNA expression of HIF1-α and Tβ-4 along with hemocyte counts, biomarkers of hypoxic stress and immune health, respectively, were measured. In field-deployed oysters, HIF1-α and Tβ-4 expression increased, while no effect on hemocytes was …

Shallow-Water Coral Communities Support The Separation Of Marine Ecoregions On The West-Central Florida Gulf Coast, Brian K. Walker, Shelby Eagan, Cory Ames, Sandra Brooke, Sean Keenan, Rene Baumstark

Marine & Environmental Sciences Faculty Articles

Florida’s west coast is a 170,000 km² bedrock shelf (west Florida shelf, WFS) comprised of north-south discontinuous carbonate outcroppings extending more than 200 km from the intertidal zone to a depth of 200 m. These outcrops support diverse benthic communities, which contribute to a multi-billion dollar recreational and commercial fishing industry, yet only about 5% of their extent has been studied in detail. Benthic communities shift over a 6.5° geographic range, but the locations of these shifts are not well-defined. Previous studies have suggested a break in biogeographic regions at Tampa Bay, south at Cape Romano, and north at …

Antioxidant, Anti-Inflammatory, And Hep G2 Cell Growth-Inhibitory Effects Of Aqueous-Ethanol Extracts Obtained From Non-Puffed And Compressional-Puffed Sargassum Crassifolium, Cheng-Yuan Wang, Tien-Chiu Wu, Chien-Hui Wu, Yung-Hsiang Tsai, Shun-Min Chung, Yong-Han Hong, Chun-Yung Huang

Journal of Marine Science and Technology–Taiwan

There is growing interest in the bioactive components of marine algae due to their biomedical importance. In this study, a compressional-puffing (CP) process was adopted to pretreat algal samples of Sargassum crassifolium (SC), and the bioactive components of non-puffed and compressional-puffed SCs were extracted using aqueous-ethanol solution. Two extracts, namely, NPSC (non-puffed) and CPSC (compressional-puffed) were obtained, and their compositions were analyzed and compared. It was found that the composition of CPSC extract was different from that of NPSC. Further biological activity studies revealed that extracts of both NPSC and CPSC exhibited antioxidant activity, but only NPSC extract showed anti-inflammatory …

Benchmarking And Parameter Sensitivity Of Physiological And Vegetation Dynamics Using The Functionally Assembled Terrestrial Ecosystem Simulator (Fates) At Barro Colorado Island, Panama, Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto

School of Earth, Environmental, & Marine Sciences Faculty Publications

Plant functional traits determine vegetation responses to environmental variation, but variation in trait values is large, even within a single site. Likewise, uncertainty in how these traits map to Earth system feedbacks is large. We use a vegetation demographic model (VDM), the Functionally Assembled Terrestrial Ecosystem Simulator (FATES), to explore parameter sensitivity of model predictions, and comparison to observations, at a tropical forest site: Barro Colorado Island in Panama. We define a single 12-dimensional distribution of plant trait variation, derived primarily from observations in Panama, and define plant functional types (PFTs) as random draws from this distribution. We compare several …

Effectiveness Of Topical Antibiotics In Treating Corals Affected By Stony Coral Tissue Loss Disease, Karen L. Neely, Kevin A. Macaulay, Emily K. Hower, Michelle A. Dobler

Marine & Environmental Sciences Faculty Articles

Since 2014, Stony Coral Tissue Loss Disease (SCTLD) has led to mass mortality of the majority of hard coral species on the Florida Reef Tract. Following the successful treatment of SCTLD lesions on laboratory corals using water dosed with antibiotics, two topical pastes were developed as vehicles to directly apply antibiotic treatments to wild corals. These pastes were tested as placebos and with additions of amoxicillin on active SCTLD lesions on multiple coral species. The effectiveness of the pastes without antibiotics (placebo treatments) was 4% and 9%, no different from untreated controls. Adding amoxicillin to both pastes significantly increased effectiveness …

Trip Bs01 - Perc Pll Trip Bs01 - Jun-July 2020 Set Data, David Kerstetter, Sean T. Wilms, Brittany N. Savercool, Ellyn Willse

PERC Pelagic Longline Field Datasheets

Field datasheets from pelagic longline sets in the western North Atlantic from 2020-2022.

Trip Dk01 - Perc Pll Trip Dk01 - Jun-July 2020 Set 1, David Kerstetter, Sean T. Wilms, Brittany N. Savercool, Ellyn Willse

PERC Pelagic Longline Field Datasheets

Field datasheets from pelagic longline sets in the western North Atlantic from 2020-2022.