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Full-Text Articles in Life Sciences

Seaflow Data V1, High-Resolution Abundance, Size And Biomass Of Small Phytoplankton In The North Pacific, François Ribalet, Chris Berthiaume, Annette Hynes, Jarred Swalwell, Michael Carlson, Sophie Clayton, Gwenn Hennon, Camille Poirier, Eric Shimabukuro, Angelicque White, E. Virginia Armhurst Nov 2019

Seaflow Data V1, High-Resolution Abundance, Size And Biomass Of Small Phytoplankton In The North Pacific, François Ribalet, Chris Berthiaume, Annette Hynes, Jarred Swalwell, Michael Carlson, Sophie Clayton, Gwenn Hennon, Camille Poirier, Eric Shimabukuro, Angelicque White, E. Virginia Armhurst

OES Faculty Publications

SeaFlow is an underway flow cytometer that provides continuous shipboard observations of the abundance and optical properties of small phytoplankton (μm in equivalent spherical diameter, ESD). Here we present data sets consisting of SeaFlow-based cell abundance, forward light scatter, and pigment fluorescence of individual cells, as well as derived estimates of ESD and cellular carbon content of picophytoplankton, which includes the cyanobacteria Prochlorococcus, Synechococcus and small-sized Crocosphaera (μm ESD), and picophytoplankton and nanophytoplankton (2–5 μm ESD). Data were collected in surface waters (≈5 m depth) from 27 oceanographic cruises carried out in the Northeast Pacific Ocean between 2010 and 2018. …


Nutrient Controls Over Cyanobacterial Synthesis Of The Neurotoxin Β-N-Methylamino-L-Alanine (Bmaa) And Its Potential Accumulation In The Blue Crab (Callinectes Sapidus), Madeline M. Hummel Jul 2019

Nutrient Controls Over Cyanobacterial Synthesis Of The Neurotoxin Β-N-Methylamino-L-Alanine (Bmaa) And Its Potential Accumulation In The Blue Crab (Callinectes Sapidus), Madeline M. Hummel

OES Theses and Dissertations

Cyanobacteria are known to produce a variety of toxins that negatively impact both aquatic and terrestrial organisms. One putative neurotoxic compound is the non-protein amino acid β-N-methylamino-L-alanine (BMAA), which has epidemiological linkages to the development of several human neurological diseases. Three cyanobacterial species thought to produce BMAA —Microcystis aeruginosa, Synechococcus bacillaris, and Nostoc sp. —were grown in nutrient replete cultures to examine its synthesis and cellular distribution over a growth cycle. Production of BMAA was also examined in nutrient (nitrogen and phosphorus) deplete cultures of Microcystis aeruginosa. In addition, natural assemblages of phytoplankton dominated by …


Sponge Community Biocomplexity, Competition, And Functional Significance In Hard-Bottom Habitats Of The Florida Keys, Fl (Usa), Marla Maxine Valentine Apr 2019

Sponge Community Biocomplexity, Competition, And Functional Significance In Hard-Bottom Habitats Of The Florida Keys, Fl (Usa), Marla Maxine Valentine

Biological Sciences Theses & Dissertations

Sponges can have powerful effects on ecosystem processes in shallow, tropical marine ecosystems and are an integral component of the bentho-pelagic cycle of nutrients, via filtering of dissolved and particulate organic matter from the water column. The diversity of marine communities is thought to play a determining role in intensity of ecosystem processes; thus the loss of taxa alters community function and by extension ecosystem processes. Coastal sponge populations worldwide are increasingly exposed to declining water quality that in several regions has resulted in mass sponge mortalities and reduced sponge diversity. In the Florida Keys (Florida, USA), for example, frequent …


Correction: New Approaches For Assessing Squid Fin Motions: Coupling Proper Orthogonal Decomposition With Volumetric Particle Tracking Velocimetry (Doi:10.1242/Jeb.176750), Ian K. Bartol, Paul S. Krueger, Carly A. York, Joseph T. Thompson Feb 2019

Correction: New Approaches For Assessing Squid Fin Motions: Coupling Proper Orthogonal Decomposition With Volumetric Particle Tracking Velocimetry (Doi:10.1242/Jeb.176750), Ian K. Bartol, Paul S. Krueger, Carly A. York, Joseph T. Thompson

Biological Sciences Faculty Publications

Squid, which swim using a coupled fin/jet system powered by muscular hydrostats, pose unique challenges for the study of locomotion. The high flexibility of the fins and complex flow fields generated by distinct propulsion systems require innovative techniques for locomotive assessment. For this study, we used proper orthogonal decomposition (POD) to decouple components of the fin motions and defocusing digital particle tracking velocimetry (DDPTV) to quantify the resultant 3D flow fields. Kinematic footage and DDPTV data were collected from brief squid, Lolliguncula brevis [3.1–6.5 cm dorsal mantle length (DML)], swimming freely in a water tunnel at speeds of 0.39–7.20 DML …


Bomb Radiocarbon Age Validation For The Long-Lived, Unexploited Arctic Fish Species Coregonus Clupeaformis, John M. Casselman, Cynthia M. Jones, Steven E. Campana Jan 2019

Bomb Radiocarbon Age Validation For The Long-Lived, Unexploited Arctic Fish Species Coregonus Clupeaformis, John M. Casselman, Cynthia M. Jones, Steven E. Campana

OES Faculty Publications

The growth rates of freshwater fish in the Arctic would be expected to be very low, but some previous studies of lake whitefish (Coregonus clupeaformis) have reported relatively rapid growth and longevity estimates of less than 15 years. We used bomb radiocarbon chronologies to validate an ageing method based on otolith sections for lake whitefish in both an unexploited Arctic lake (MacAlpine Lake; longevity 50 years) and a lightly exploited temperate population (Lake Simcoe; longevity 49 years). Our results confirm previous suggestions that other ageing methods can seriously underestimate lake whitefish age after ~5–8 years. A Chapman–Robson estimate …


Editorial: Advances In The Biology And Conservation Of Marine Turtles, Sara M. Maxwell, Annette C. Broderick, Peter H. Dutton, Sabrina Fossette-Halot, Mariana M.P.B. Fuentes, Richard D. Reina Jan 2019

Editorial: Advances In The Biology And Conservation Of Marine Turtles, Sara M. Maxwell, Annette C. Broderick, Peter H. Dutton, Sabrina Fossette-Halot, Mariana M.P.B. Fuentes, Richard D. Reina

Biological Sciences Faculty Publications

(First Paragraph) Marine turtles have been the subject of research over many decades, inspired by their unique life history and necessitated by their declining populations from a suite of human impacts including direct harvest, bycatch in marine fisheries, pollution, and climate change. Despite this, much about marine turtle biology has remained a mystery (Godley et al., 2008; Rees et al., 2016; Wildermann et al., 2018), but the rate of scientific discovery is increasing rapidly. As research techniques and conservation practices expand, the marine turtle research community has kept abreast of these developments and their application to marine turtles. In this …


Mapping Status And Conservation Of Global At-Risk Marine Biodiversity, Casey C. O'Hara, Juan Carlos Villaseñor-Derbez, Gina M. Ralph, Benjamin S. Halpern Jan 2019

Mapping Status And Conservation Of Global At-Risk Marine Biodiversity, Casey C. O'Hara, Juan Carlos Villaseñor-Derbez, Gina M. Ralph, Benjamin S. Halpern

Biological Sciences Faculty Publications

To conserve marine biodiversity, we must first understand the spatial distribution and status of at‐risk biodiversity. We combined range maps and conservation status for 5,291 marine species to map the global distribution of extinction risk of marine biodiversity. We find that for 83% of the ocean, >25% of assessed species are considered threatened, and 15% of the ocean shows >50% of assessed species threatened when weighting for range‐limited species. By comparing mean extinction risk of marine biodiversity to no‐take marine reserve placement, we identify regions where reserves preferentially afford proactive protection (i.e., preserving low‐risk areas) or reactive protection (i.e., mitigating …


Parasitic Dinoflagellate Hematodinium Perezi Prevalence In Larval And Juvenile Blue Crabs Callinectes Sapidus From Coastal Bays Of Virginia, H. J. Small, J. P. Huchin-Mian, K. S. Reece, K. M. Pagenkopp Lohan, Mark J. Butler Iv, J. D. Shields Jan 2019

Parasitic Dinoflagellate Hematodinium Perezi Prevalence In Larval And Juvenile Blue Crabs Callinectes Sapidus From Coastal Bays Of Virginia, H. J. Small, J. P. Huchin-Mian, K. S. Reece, K. M. Pagenkopp Lohan, Mark J. Butler Iv, J. D. Shields

Biological Sciences Faculty Publications

The parasitic dinoflagellate Hematodinium perezi infects the American blue crab Callinectes sapidus and other decapods along the Eastern seaboard and Gulf of Mexico coast of the USA. Large juvenile and adult blue crabs experience high mortality during seasonal outbreaks of H. perezi, but less is known about its presence in the early life history stages of this host. We determined the prevalence of H. perezi in megalopae and early benthic juvenile crabs from multiple locations along the Virginia portion of the Delmarva Peninsula. The DNA of H. perezi was not detected in any megalopae collected from several locations within …


A Full-Ocean-Depth Rated Modular Lander And Pressure-Retaining Sampler Capable Of Collecting Hadal-Endemic Microbes Under In Situ Conditions, Logan M. Peoples, Matthew Norenberg, David Price, Madeline Mcgoldrick, Mark Novotny, Alexander Bochdansky, Douglas H. Bartlett Jan 2019

A Full-Ocean-Depth Rated Modular Lander And Pressure-Retaining Sampler Capable Of Collecting Hadal-Endemic Microbes Under In Situ Conditions, Logan M. Peoples, Matthew Norenberg, David Price, Madeline Mcgoldrick, Mark Novotny, Alexander Bochdansky, Douglas H. Bartlett

OES Faculty Publications

The hadal zone remains one of the least studied environments because of its inaccessibility, in part because of hydrostatic pressures extending to 110 MPa. Few instruments are capable of sampling from such great depths. We have developed a full-ocean-depth-capable lander that can be fit with sampling packages for the collection of still images, video, motile megafauna, and hadal seawater. One payload includes a pressure-retaining sampler (PRS) able to maintain seawater samples under in situ pressure during recovery. We describe the technical specifications of the lander and the PRS and preliminary results from three deployments at depths in excess of 10,700 …


Spatial Structuring And Life History Connectivity Of Antarctic Silverfish Along The Southern Continental Shelf Of The Weddell Sea, Jilda Alicia Caccavo, Julian R. Ashford, Svenja Ryan, Chiara Papetti, Michael Schröder, Lorenzo Zane Jan 2019

Spatial Structuring And Life History Connectivity Of Antarctic Silverfish Along The Southern Continental Shelf Of The Weddell Sea, Jilda Alicia Caccavo, Julian R. Ashford, Svenja Ryan, Chiara Papetti, Michael Schröder, Lorenzo Zane

OES Faculty Publications

A multi-disciplinary approach was employed to examine a physical-biological population hypothesis for a critical forage species, the Antarctic silverfish Pleuragramma antarctica. Caccavo et al. (2018; Sci Rep 8:17856) had shown strong gene flow along the westward Antarctic Slope Current, in addition to spatially recurring length modes that provided evidence for episodic connectivity. In this paper, otolith nucleus chemistry from a subset of fish collected in the southern Weddell Sea as part of a hydrographic survey of the Filchner Trough system was used to test between connectivity scenarios. Nucleus chemistry, which reflects environmental exposure during early life, showed significant …


Patterns Of Diatom Diversity Correlate With Dissolved Trace Metal Concentrations And Longitudinal Position In The Notheast Pacific Coastal Offshore Transition Zone, P. Dreux Chappell, E. Virginia Armbrust, Katherine A. Barbeau, Randelle M. Bundy, Jagruti Vedamati, Bethany D. Jenkins Jan 2019

Patterns Of Diatom Diversity Correlate With Dissolved Trace Metal Concentrations And Longitudinal Position In The Notheast Pacific Coastal Offshore Transition Zone, P. Dreux Chappell, E. Virginia Armbrust, Katherine A. Barbeau, Randelle M. Bundy, Jagruti Vedamati, Bethany D. Jenkins

OES Faculty Publications

Diatoms are important primary producers in the northeast Pacific Ocean, with their productivity closely linked to pulses of trace elements in the western high nitrate, low chlorophyll (HNLC) region of the oceanographic time series transect 'Line P.' Recently, the coastal-HNLC transition zone of the Line P transect was identified as a hotspot of phytoplankton productivity, potentially controlled by a combination of trace element and macronutrient concentrations. Here we describe diatom community composition in the eastern Line P transect, including the coastal- HNLC transition zone, with a method using high-throughput sequencing of diatom 18S gene amplicons. We identified significant correlations between …


Seasonal Spatial Segregation In Blue Sharks (Prionace Glauca) By Sex And Size Class In The Northeast Pacific Ocean, Sara M. Maxwell, Kylie L. Scales, Steven Bograd, Dana K. Briscoe, Heidi Dewar, Elliott L. Hazen, Rebecca L. Lewison, Heather Welch, Larry B. Crowder Jan 2019

Seasonal Spatial Segregation In Blue Sharks (Prionace Glauca) By Sex And Size Class In The Northeast Pacific Ocean, Sara M. Maxwell, Kylie L. Scales, Steven Bograd, Dana K. Briscoe, Heidi Dewar, Elliott L. Hazen, Rebecca L. Lewison, Heather Welch, Larry B. Crowder

Biological Sciences Faculty Publications

Aim: Animal tracking can provide unique insights into the ecology and conservation of marine species, such as the partitioning of habitat, including differences between life history stages or sexes, and can inform fisheries stock assessments, bycatch reduction and spatial management such as dynamic management.

Location: Northeast Pacific Ocean.

Methods: We used satellite tracking data from 47 blue sharks (Prionace glauca) from the Northeast Pacific to determine movements and home range along the west coast of North America, and sex–size class (immature females, mature males) specific habitat preferences using boosted regression trees. Using a suite of static and dynamic …


Adaptive Signatures In Thermal Performance Of The Temperate Coral Astrangia Poculata, H. E. Aichelman, Richard C. Zimmerman, Daniel J. Barshis Jan 2019

Adaptive Signatures In Thermal Performance Of The Temperate Coral Astrangia Poculata, H. E. Aichelman, Richard C. Zimmerman, Daniel J. Barshis

Biological Sciences Faculty Publications

Variation in environmental characteristics and divergent selection pressures can drive adaptive differentiation across a species' range. Astrangia poculata is a temperate scleractinian coral that provides unique opportunities to understand the roles of phenotypic plasticity and evolutionary adaptation in coral physiological tolerance limits. A. poculata inhabits hard bottom ecosystems from the northwestern Atlantic to the Gulf of Mexico and withstands an annual temperature range up to 20° C. Additionally, A. poculata is facultatively symbiotic and co-occurs in both symbiotic ("brown") and aposymbiotic ("white") states. Here, brown and white A. poculata were collected from Virginia (VA) and Rhode Island (RI), USA and …


Sponges Structure Water-Column Characteristics In Shallow Tropical Coastal Ecosystems, Marla M. Valentine, Mark J. Butler Iv Jan 2019

Sponges Structure Water-Column Characteristics In Shallow Tropical Coastal Ecosystems, Marla M. Valentine, Mark J. Butler Iv

Biological Sciences Faculty Publications

Sponges can have powerful effects on ecosystem processes in shallow tropical marine ecosystems. They drive benthic-pelagic coupling by filtering dissolved and particulate organic matter from the water column, alter water chemistry in association with their symbiotic microorganisms, and increase habitat structural complexity. Anthropogenic degradation of coastal waters is widespread and can reduce the density and diversity of foundation species such as sponges, potentially diminishing their contributions to ecosystem processes. We used a novel mesocosm design that minimized artifacts associated with traditional single-species and closed-system filtration experiments to examine the effects of water turnover and sponge biomass on water-column properties. Using …