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VIMS Articles

2019

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Full-Text Articles in Life Sciences

Bridging Disciplines To Advance Elasmobranch Conservation: Applications Of Physiological Ecology, K Lyons, Js Bigman, Et Al, Kevin C. Weng, Et Al, Richard Brill, Cn Bedore May 2019

Bridging Disciplines To Advance Elasmobranch Conservation: Applications Of Physiological Ecology, K Lyons, Js Bigman, Et Al, Kevin C. Weng, Et Al, Richard Brill, Cn Bedore

VIMS Articles

A strength of physiological ecology is its incorporation of aspects of both species' ecology and physiology; this holistic approach is needed to address current and future anthropogenic stressors affecting elasmobranch fishes that range from overexploitation to the effects of climate change. For example, physiology is one of several key determinants of an organism's ecological niche (along with evolutionary constraints and ecological interactions). The fundamental role of physiology in niche determination led to the development of the field of physiological ecology. This approach considers physiological mechanisms in the context of the environment to understand mechanistic variations that beget ecological trends. Physiological …


A General Theory Of Age-Length Keys: Combining The Forward And Inverse Keys To Estimate Age Composition From Incomplete Data, Lisa E. Ailloud, John M. Hoenig Apr 2019

A General Theory Of Age-Length Keys: Combining The Forward And Inverse Keys To Estimate Age Composition From Incomplete Data, Lisa E. Ailloud, John M. Hoenig

VIMS Articles

There are two approaches to estimating age composition from a large number of length observations and a limited number of age determinations: the forward and the inverse age-length keys. The forward key looks at the distribution of age within each length bin while the inverse key looks at the distribution of length at each age. The former is more precise but has stringent requirements for the way data are collected. The latter approach is more widely applicable. We review the theory of the two keys with particular attention to necessary assumptions and the restrictions on when the methods are applicable. …


A Data-Driven Modeling Approach For Simulating Algal Blooms In The Tidal Freshwater Of James River In Response To Riverine Nutrient Loading, Jian Shen, Qubin Qin, Ya Wang, Mac Sisson Apr 2019

A Data-Driven Modeling Approach For Simulating Algal Blooms In The Tidal Freshwater Of James River In Response To Riverine Nutrient Loading, Jian Shen, Qubin Qin, Ya Wang, Mac Sisson

VIMS Articles

Algal blooms often occur in the tidal freshwater (TF) of the James River estuary, a tributary of the Chesapeake Bay. The timing of algal blooms correlates highly to a summer low-flow period when residence time is long and nutrients are available. Because of complex interactions between physical transport and algal dynamics, it is challenging to predict interannual variations of bloom correctly using a complex eutrophication model without having ahigh-resolution model gridto resolve complexgeometryand anaccurate estimate of nutrientloading to drive the model. In this study, an approach using long-term observational data (from 1990 to 2013) and the Support vector machine (LS-SVM) …


Estimating Age Composition For Multiple Years When There Are Gaps In The Ageing Data: The Case Of Western Atlantic Bluefin Tuna, Lisa E. Ailloud, Matthew V. Lauretta, John F. Walter Iii, John M. Hoenig Apr 2019

Estimating Age Composition For Multiple Years When There Are Gaps In The Ageing Data: The Case Of Western Atlantic Bluefin Tuna, Lisa E. Ailloud, Matthew V. Lauretta, John F. Walter Iii, John M. Hoenig

VIMS Articles

Age–length key (ALK) methods generally perform well when length samples and age samples are representative of the underlying population. It is unclear how well these methods perform when lengths are representative but age samples are sparse (i.e. age samples are small or missing in many years, and some length groups do not have any age observations). With western Atlantic bluefin tuna, the available age data are sparse and have been, for the most part, collected opportunistically. We evaluated two methods capable of accommodating sparse age data: a novel hybrid ALK (combining forward ALKs and cohort slicing) and the combined forward-inverse …


Advancing Marine Biogeochemical And Ecosystem Reanalyses And Forecasts As Tools For Monitoring And Managing Ecosystem Health, K Fennel, M Gehlen, P Brasseur, Cw Brown, C Ciavatta, G Cossarini, A Crise, Ca Edwards, D Ford, Marjorie A.M. Friedrichs, Et Al Mar 2019

Advancing Marine Biogeochemical And Ecosystem Reanalyses And Forecasts As Tools For Monitoring And Managing Ecosystem Health, K Fennel, M Gehlen, P Brasseur, Cw Brown, C Ciavatta, G Cossarini, A Crise, Ca Edwards, D Ford, Marjorie A.M. Friedrichs, Et Al

VIMS Articles

Ocean ecosystems are subject to a multitude of stressors, including changes in ocean physics and biogeochemistry, and direct anthropogenic influences. Implementation of protective and adaptive measures for ocean ecosystems requires a combination of ocean observations with analysis and prediction tools. These can guide assessments of the current state of ocean ecosystems, elucidate ongoing trends and shifts, and anticipate impacts of climate change and management policies. Analysis and prediction tools are defined here as ocean circulation models that are coupled to biogeochemical or ecological models. The range of potential applications for these systems is broad, ranging from reanalyses for the assessment …


The Mechanisms Of Phenology: The Patterns And Processes Of Phenological Shifts, Helen E. Chmura, Heather M Kharouba, Jaime Ashander, Sean M. Ehlman, Emily B. Rivest, Louie H. Yang Feb 2019

The Mechanisms Of Phenology: The Patterns And Processes Of Phenological Shifts, Helen E. Chmura, Heather M Kharouba, Jaime Ashander, Sean M. Ehlman, Emily B. Rivest, Louie H. Yang

VIMS Articles

Species across a wide range of taxa and habitats are shifting phenological events in response to climate change. While advances are common, shifts vary in magnitude and direction within and among species, and the basis for this variation is relatively unknown. We examine previously suggested patterns of variation in phenological shifts in order to understand the cue-response mechanisms that underlie phenological change. Here, we review what is known about the mechanistic basis for nine factors proposed to predict phenological change (latitude, elevation, habitat type, trophic level, migratory strategy, ecological specialization, species' seasonality, thermoregulatory mode, and generation time). We find that …


Examining Derelict Pot Impacts On Harvest In A Commercial Blue Crab Callinectes Sapidus Fishery, James A. Delbene, Donna M. Bilkovic, Andrew M. Scheld Feb 2019

Examining Derelict Pot Impacts On Harvest In A Commercial Blue Crab Callinectes Sapidus Fishery, James A. Delbene, Donna M. Bilkovic, Andrew M. Scheld

VIMS Articles

Pot fisheries occur worldwide with a significant proportion of the gear becoming derelict. Derelict pots induce detrimental ecological and economic impacts, and more recently were found to reduce blue crab harvests in the Chesapeake Bay commercial fishery. We simulated the presence of derelict pots near actively fished pots in seasonal field experiments to quantify the effect derelict pots have on blue crab harvest. Derelict pots reduced harvests by 30% during the summer, but not during the fall. Female blue crab capture rates were consistently lower when derelict pots were present; while capture rates of the less abundant males were not …


Vertical Stratification Of Sediment Microbial Communities Along Geochemical Gradients Of A Subterranean Estuary Located At The Gloucester Beach Of Virginia, United States, Yiguo Hong, Jiapeng Wu, Stephanie Wilson, Bk Song Jan 2019

Vertical Stratification Of Sediment Microbial Communities Along Geochemical Gradients Of A Subterranean Estuary Located At The Gloucester Beach Of Virginia, United States, Yiguo Hong, Jiapeng Wu, Stephanie Wilson, Bk Song

VIMS Articles

Subterranean estuaries (STEs) have been recognized as important ecosystems for the exchange of materials between the land and sea, but the microbial players of biogeochemical processes have not been well examined. In this study, we investigated the bacterial and archaeal communities within 10 cm depth intervals of a permeable sediment core (100 cm in length) collected from a STE located at Gloucester Point (GP-STE), VA, United States. High throughput sequencing of 16S rRNA genes and subsequent bioinformatics analyses were conducted to examine the composition, diversity, and potential functions of the sediment communities. The community composition varied significantly from the surface …


The Invisible Flood: The Chemistry, Ecology, And Social Implications Of Coastal Saltwater Intrusion, Kate Tully, Keryn Gedan, (...), Molly Mitchell, Et Al Jan 2019

The Invisible Flood: The Chemistry, Ecology, And Social Implications Of Coastal Saltwater Intrusion, Kate Tully, Keryn Gedan, (...), Molly Mitchell, Et Al

VIMS Articles

Saltwater intrusion is the leading edge of sea-level rise, preceding tidal inundation, but leaving its salty signature far inland. With climate change, saltwater is shifting landward into regions that previously have not experienced or adapted to salinity, leading to novel transitions in biogeochemistry, ecology, and human land uses. We explore these changes and their implications for climate adaptation in coastal ecosystems. Biogeochemical changes, including increases in ionic strength, sulfidation, and alkalinization, have cascading ecological consequences such as upland forest retreat, conversion of freshwater wetlands, nutrient mobilization, and declines in agricultural productivity. We explore the tradeoffs among land management decisions in …


Evaluating Confidence In The Impact Of Regulatory Nutrient Reduction On Chesapeake Bay Water Quality, Isaac D. Irby, Marjorie A.M. Friedrichs Jan 2019

Evaluating Confidence In The Impact Of Regulatory Nutrient Reduction On Chesapeake Bay Water Quality, Isaac D. Irby, Marjorie A.M. Friedrichs

VIMS Articles

Excess nutrients derived from anthropogenic activity have resulted in the degradation of coastal water quality and an increase in low-oxygen and hypoxic events worldwide. In an effort to curb these impacts and restore water quality in the Chesapeake Bay, a maximum load of nutrients has been established based on a framework of regulatory standards and models. This research aims to evaluate the projected changes in water quality resulting from the implementation of these nutrient reductions by applying the regulatory methodology to two different models that have been previously shown to have similar model skill. Results demonstrate that although the two …


Tracking Triploid Mortalities Of Eastern Oysters Crassostrea Virginica In The Virginia Portion Of The Chesapeake Bay, Eric Guevelou, Ryan Carnegie, Ja Moss, Karen Hudson, Kimberly S. Reece, Molly M. Rybovich, Standish K. Allen Jr. Jan 2019

Tracking Triploid Mortalities Of Eastern Oysters Crassostrea Virginica In The Virginia Portion Of The Chesapeake Bay, Eric Guevelou, Ryan Carnegie, Ja Moss, Karen Hudson, Kimberly S. Reece, Molly M. Rybovich, Standish K. Allen Jr.

VIMS Articles

Since 2012, aquacultured eastern oysters Crassostrea virginica have been reported by oyster farmers to display mortality approaching 30%, and in some cases 85%, in areas of the lower Chesapeake Bay, VA. Based on accounts from industry, this mortality has typically affected 1-y-old oysters between May and early July, and has tended to occur in triploid oysters, which represent the vast bulk of production in the area. During this period, samples submitted for pathology have not revealed the presence of major pathogens as a cause. In 2015, to gain deeper insight into this mortality and determine whether specific sites, ploidy condition, …


The Impacts Of Warming And Hypoxia On The Performance Of An Obligate Ram Ventilator, Daniel P. Crear, Richard Brill, Peter G. Bushnell, Robert J. Latour, Gail D. Schwieterman, Rachel M. Steffen, Kevin C. Weng Jan 2019

The Impacts Of Warming And Hypoxia On The Performance Of An Obligate Ram Ventilator, Daniel P. Crear, Richard Brill, Peter G. Bushnell, Robert J. Latour, Gail D. Schwieterman, Rachel M. Steffen, Kevin C. Weng

VIMS Articles

Climate change is causing the warming and deoxygenation of coastal habitats like Chesapeake Bay that serve as important nursery habitats for many marine fish species. As conditions continue to change, it is important to understand how these changes impact individual species' behavioral and metabolic performance. The sandbar shark (Carcharhinus plumbeus) is an obligate ram-ventilating apex predator whose juveniles use Chesapeake Bay as a nursery ground up to 10 years of age. The objective of this study was to measure juvenile sandbar shark metabolic and behavioral performance as a proxy for overall performance (i.e. fitness or success) when exposed to warm …


Method For Serial Passage Of Infectious Hematopoietic Necrosis Virus (Ihnv) In Rainbow Trout, Juliette Doumayrou, M. Gray Ryan, Andrew R. Wargo Jan 2019

Method For Serial Passage Of Infectious Hematopoietic Necrosis Virus (Ihnv) In Rainbow Trout, Juliette Doumayrou, M. Gray Ryan, Andrew R. Wargo

VIMS Articles

Transmission is a fundamental component of pathogen fitness. A better understanding of pathogen transmission can greatly improve disease management. In particular, controlled studies of multiple rounds of natural transmission (i.e. serial passage) can provide powerful epidemiological and evolutionary inferences. However, such studies are possible in only a few systems because of the challenges in successfully initiating and maintaining transmission in the laboratory. Here we developed an efficient and reproducible cohabitation method for conducting controlled experiments investigating the effects of serial passage on infectious hematopoietic necrosis virus (IHNV) in rainbow trout. This method was used to investigate the transmission efficiency and …


Prey Lysate Enhances Growth And Toxin Production In An Isolate Of Dinophysis Acuminata, Han Gao, Mengmeng Tong, Xinlong An, Juliette L. Smith Jan 2019

Prey Lysate Enhances Growth And Toxin Production In An Isolate Of Dinophysis Acuminata, Han Gao, Mengmeng Tong, Xinlong An, Juliette L. Smith

VIMS Articles

The physiological and toxicological characteristics of Dinophysis acuminata have been increasingly studied in an attempt to better understand and predict diarrhetic shellfish poisoning (DSP) events worldwide. Recent work has identified prey quantity, organic nitrogen, and ammonium as likely contributors to increased Dinophysis growth rates and/or toxicity. Further research is now needed to better understand the interplay between these factors, for example, how inorganic and organic compounds interact with prey and a variety of Dinophysis species and/or strains. In this study, the exudate of ciliate prey and cryptophytes were investigated for an ability to support D. acuminata growth and toxin production …


Krill (Euphausia Superba) Distribution Contracts Southward During Rapid Regional Warming, A. Atkinson, S. L. Hill, (...), Deborah K. Steinberg, Et Al Jan 2019

Krill (Euphausia Superba) Distribution Contracts Southward During Rapid Regional Warming, A. Atkinson, S. L. Hill, (...), Deborah K. Steinberg, Et Al

VIMS Articles

High-latitude ecosystems are among the fastest warming on the planet1. Polar species may be sensitive to warming and ice loss, but data are scarce and evidence is conflicting2–4. Here, we show that, within their main population centre in the southwest Atlantic sector, the distribution of Euphausia superba (hereafter, ‘krill’) has contracted southward over the past 90 years. Near their northern limit, numerical densities have declined sharply and the population has become more concentrated towards the Antarctic shelves. A concomitant increase in mean body length reflects reduced recruitment of juvenile krill. We found evidence for environmental controls …


Herbivory Regulates The Establishment Of A Native Species Of Submerged Aquatic Vegetation (Sav) In A Tidal Estuary Of The Usa, A. J. Johnson, R. J. Orth, Ken Moore Jan 2019

Herbivory Regulates The Establishment Of A Native Species Of Submerged Aquatic Vegetation (Sav) In A Tidal Estuary Of The Usa, A. J. Johnson, R. J. Orth, Ken Moore

VIMS Articles

Herbivores are a diverse group of fauna that shape the distribution and composition of plant communities. In some cases, herbivory may prevent the re-establishment of submerged aquatic vegetation (SAV), such as Vallisneria americana, into systems. The goal of this study was to investigate the role and nature of herbivory on V. americana transplants with camera and transect surveys of grazing intensity and with field and laboratory grazing experiments using a suspected herbivore, the blue crab, Callinectes sapidus. Camera surveys recorded C. sapidus clipping and consuming shoots of V. americana for the first time. Grazing intensity surveys in low-salinity …


A Novel Adaptation Facilitates Seed Establishment Under Marine Turbulent Flows, Gary A. Kendrick, Andrew W. Pomeroy, R J. Orth, Marion L. Cambridge, Jeremy Shaw, Et Al Jan 2019

A Novel Adaptation Facilitates Seed Establishment Under Marine Turbulent Flows, Gary A. Kendrick, Andrew W. Pomeroy, R J. Orth, Marion L. Cambridge, Jeremy Shaw, Et Al

VIMS Articles

Seeds of Australian species of the seagrass genus Posidonia are covered by a membranous wing that we hypothesize plays a fundamental role in seed establishment in sandy, wave swept marine environments. Dimensions of the seed and membrane were quantified under electron microscopy and micro-CT scans, and used to model rotational, drag and lift forces. Seeds maintain contact with the seabed in the presence of strong turbulence: the larger the wing, the more stable the seed. Wing surface area increases from P. sinuosa < P. australis < P.coriacea correlating with their ability to establish in increasingly energetic environments. This unique seed trait in …


Alkalinity In Tidal Tributaries Of The Chesapeake Bay, R. G. Najjar, M. Herrmann, S. M. Cintrón Del Valle, Jaclyn R. Friedman, Marjorie A.M. Friedrichs, Et Al Jan 2019

Alkalinity In Tidal Tributaries Of The Chesapeake Bay, R. G. Najjar, M. Herrmann, S. M. Cintrón Del Valle, Jaclyn R. Friedman, Marjorie A.M. Friedrichs, Et Al

VIMS Articles

Despite the important role of alkalinity in estuarine carbon cycling, the seasonal and decadal variability of alkalinity, particularly within multiple tidal tributaries of the same estuary, is poorly understood. Here we analyze more than 25,000 alkalinity measurements, mostly from the 1980s and 1990s,in the major tidal tributaries of the Chesapeake Bay, a large, coastal‐plain estuary of eastern North America.The long‐term means of alkalinity in tidal‐fresh waters vary by a factor of 6 among seven tidal tributaries,reflecting the alkalinity of nontidal rivers draining to these estuaries. At 25 stations, mostly in the Potomac River Estuary, wefind significant long‐term increasing trends that …


Are Coastal Habitats Important Nurseries? A Meta-Analysis, Jonathan S. Lefcheck, Brent B. Hughes, Andrew J. Johnson, Bruce W. Pfirrman, Douglas B. Rasher, Ashley R. Smyth, Bethany L. Williams, Michael W. Beck, R J. Orth Jan 2019

Are Coastal Habitats Important Nurseries? A Meta-Analysis, Jonathan S. Lefcheck, Brent B. Hughes, Andrew J. Johnson, Bruce W. Pfirrman, Douglas B. Rasher, Ashley R. Smyth, Bethany L. Williams, Michael W. Beck, R J. Orth

VIMS Articles

Nearshore‐structured habitats—including underwater grasses, mangroves, coral, and other biogenic reefs, marshes, and complex abiotic substrates—have long been postulated to function as important nurseries for juvenile fishes and invertebrates. Here, we review the evolution of the “nursery habitat hypothesis” and use >11,000 comparisons from 160 peer‐reviewed studies to test whether and which structured habitats increase juvenile density, growth, and survival. In general, almost all structured habitats significantly enhanced juvenile density—and in some cases growth and survival—relative to unstructured habitats. Underwater grasses and mangroves also promoted juvenile density and growth beyond what was observed in other structured habitats. These conclusions were robust …


The Effect Of A Small Vegetation Dieback Event On Salt Marsh Sediment Transport, Daniel J. Coleman, Matthew L. Kirwan Jan 2019

The Effect Of A Small Vegetation Dieback Event On Salt Marsh Sediment Transport, Daniel J. Coleman, Matthew L. Kirwan

VIMS Articles

Vegetation is a critical component of the ecogeomorphic feedbacks that allow a salt marsh to build soil and accrete vertically. Vegetation dieback can therefore have detrimental effects on marsh stability, especially under conditions of rising sea levels. Here, we report a variety of sediment transport measurements associated with an unexpected, natural dieback in a rapidly prograding marsh in the Altamaha River Estuary, Georgia. We find that vegetation mortality led to a significant loss in elevation at the dieback site as evidenced by measurements of vertical accretion, erosion, and surface topography compared to vegetated refer- ence areas. Below-ground vegetation mortality led …


Environmental Controls On Pteropod Biogeography Along The Western Antarctic Peninsula, Patrica S. Thibodeau, Deborah K. Steinberg, Se Stammerjohn, C Hauri Jan 2019

Environmental Controls On Pteropod Biogeography Along The Western Antarctic Peninsula, Patrica S. Thibodeau, Deborah K. Steinberg, Se Stammerjohn, C Hauri

VIMS Articles

Pteropods are abundant zooplankton in the Western Antarctic Peninsula (WAP) and important grazers of phytoplankton and prey for higher trophic levels. We analyzed long-term (1993-2017) trends in summer (January-February) abundance of WAP pteropods in relation to environmental controls (sea ice, sea surface temperature, climate indices, phytoplankton biomass and productivity, and carbonate chemistry) and interspecies dynamics using general linear models. There was no overall directional trend in abundance of thecosomes, Limacina helicina antarctica and Clio pyramidata, throughout the entire WAP, although L. antarctica abundance increased in the slope region and C. pyramidata abundance increased in the South. High L. antarctica abundance …


Nursery Habitat Quality Assessed By The Condition Of Juvenile Fishes: Not All Estuarine Areas Are Equal, Ryan W. Schloesser, Mary C. Fabrizio Jan 2019

Nursery Habitat Quality Assessed By The Condition Of Juvenile Fishes: Not All Estuarine Areas Are Equal, Ryan W. Schloesser, Mary C. Fabrizio

VIMS Articles

High-quality nursery habitats support greater numbers of juveniles that survive to adulthood, but characteristics underlying high-quality habitats remain elusive because their productivity varies spatially and temporally and may be species-specific. Fish condition is an energy-integrative measure of ecological interactions, stress, and activity within a habitat, such that juvenile fish condition is representative of the quality of nursery habitats. We apply spatially explicit models to examine patterns in nursery habitat quality of Virginia estuaries based on nutritional condition for Atlantic croaker Micropogonias undulatus, summer flounder Paralichthys dentatus, and striped bass Morone saxatilis. Environmental factors (water temperature, dissolved oxygen, salinity, and depth) …


Tooth Development And Replacement In The Atlantic Cutlassfish, Trichiurus Lepturus, With Comparisons To Other Scombroidei, Katherine E. Bemis, Samantha M. Burke, Carl A. St John, Eric J. Hilton, William E. Bemis Jan 2019

Tooth Development And Replacement In The Atlantic Cutlassfish, Trichiurus Lepturus, With Comparisons To Other Scombroidei, Katherine E. Bemis, Samantha M. Burke, Carl A. St John, Eric J. Hilton, William E. Bemis

VIMS Articles

Atlantic Cutlassfish, Trichiurus lepturus, have large, barbed, premaxillary and dentary fangs, and sharp dagger-shaped teeth in their oral jaws. Functional teeth firmly ankylose to the dentigerous bones. We used dry skeletons, histology, SEM, and micro-CT scanning to study 92 specimens of T. lepturus from the western North Atlantic to describe its dentition and tooth replacement. We identified three modes of intraosseous tooth replacement in T. lepturus depending on the location of the tooth in the jaw. Mode 1 relates to replacement of premaxillary fangs, in which new tooth germs enter the lingual surface of the premaxilla, develop horizontally, and rotate …


Monitoring Demographics Of A Commercially Exploited Population Of Shovelnose Sturgeon In The Wabash River, Illinois/Indiana, Usa, Jessica L. Thornton, Vaskar Nepal, Leslie D. Frankland, Craig R. Jansen, Jana Hirst, Robert E. Colombo Jan 2019

Monitoring Demographics Of A Commercially Exploited Population Of Shovelnose Sturgeon In The Wabash River, Illinois/Indiana, Usa, Jessica L. Thornton, Vaskar Nepal, Leslie D. Frankland, Craig R. Jansen, Jana Hirst, Robert E. Colombo

VIMS Articles

Shovelnose sturgeon (Scaphirhynchus platorynchus, Rafinesque, 1820) in the Wabash River, Illinois/Indiana, USA, provide an important recreational sport and commercial caviar fishery. In fact, it is one of the last commercially viable populations for sturgeon roe harvest. Due to increased demand in the caviar trade and endangered species legislation that protect shovelnose sturgeon in only a portion of their range, efforts of the roe harvest market may continue to divert toward unprotected populations like the shovelnose sturgeon in the Wabash River. Previous studies have shown that increased harvest pressure in this species can affect the age‐at‐maturation and result in recruitment …


Variations In The Abundance And Distribution Of Aggregates In The Ross Sea, Antarctica, Vernon L. Asper, Walker O. Smith Jr. Jan 2019

Variations In The Abundance And Distribution Of Aggregates In The Ross Sea, Antarctica, Vernon L. Asper, Walker O. Smith Jr.

VIMS Articles

The vertical distribution and temporal changes in aggregate abundance and sizes were measured in the Ross Sea, Antarctica between 2002 and 2005 to acquire a more complete understanding of the mechanisms and rates of carbon export from the euphotic layer. Aggregate abundance was determined by photographic techniques, and water column parameters (temperature, salinity, fluorescence, transmissometry) were assessed from CTD profiles. During the first three years the numbers of aggregates increased seasonally, being much more abundant within the upper 200 m in late summer than in early summer from 50 to 100 m (12.5 L–1 in early summer vs. 42.9 L–1 …


The Fiddler Crab, Minuca Pugnax, Follows Bergmann's Rule, David S. Johnson, Cynthia Crowley, Katherine Longmire, Bethany Williams, Serina Wittyngham Jan 2019

The Fiddler Crab, Minuca Pugnax, Follows Bergmann's Rule, David S. Johnson, Cynthia Crowley, Katherine Longmire, Bethany Williams, Serina Wittyngham

VIMS Articles

Bergmann's rule predicts that organisms at higher latitudes are larger than ones at lower latitudes. Here, we examine the body size pattern of the Atlantic marsh fiddler crab, Minuca pugnax (formerly Uca pugnax), from salt marshes on the east coast of the United States across 12 degrees of latitude. We found that M. pugnax followed Bergmann's rule and that, on average, crab carapace width increased by 0.5 mm per degree of latitude. Minuca pugnax body size also followed the temperature–size rule with body size inversely related to mean water temperature. Because an organism's size influences its impact on an …


Evaluating Summer Flounder Spatial Sex-Segregation In A Southern New England Estuary, Joseph A. Langan, M. Conor Mcmanus, Adena J. Schonfeld, Corinne L. Truesdale, Jeremy S. Collie Jan 2019

Evaluating Summer Flounder Spatial Sex-Segregation In A Southern New England Estuary, Joseph A. Langan, M. Conor Mcmanus, Adena J. Schonfeld, Corinne L. Truesdale, Jeremy S. Collie

VIMS Articles

Marine fish species can exhibit sex-specific differences in their biological traits. Not accounting for these characteristics in the stock assessment or management of a species can lead to misunderstanding its population dynamics and result in ineffective regulatory strategies. Summer Flounder Paralichthys dentatus, a flatfish that supports significant commercial and recreational fisheries along the northeastern U.S. shelf, expresses variation in several traits between the sexes, including growth and habitat preference. To further understand these patterns, 1,302 Summer Flounder were collected and sexed in 2016 and 2017 from fisheries-independent surveys conducted in Rhode Island state waters. Female flounder were more prevalent …


Ocean Change Within Shoreline Communities: From Biomechanics To Behaviour And Beyond, Brian Gaylord, Kristina M. Barclay, Brittany M. Jellison, Laura L. Jurgens, Aaron T. Ninokawa, Emily B. Rivest, Lindsey R. Leighton Jan 2019

Ocean Change Within Shoreline Communities: From Biomechanics To Behaviour And Beyond, Brian Gaylord, Kristina M. Barclay, Brittany M. Jellison, Laura L. Jurgens, Aaron T. Ninokawa, Emily B. Rivest, Lindsey R. Leighton

VIMS Articles

Humans are changing the physical properties of Earth. In marine systems, elevated carbon dioxide concentrations are driving notable shifts in temperature and seawater chemistry. Here, we consider consequences of such perturbations for organism biomechanics and linkages amongst species within communities.In particular,we examine case examples of altered morphologies and material properties, disrupted consumer–prey behaviours, and the potential for modulated positive (i.e. facilitative) interactions amongst taxa, as incurred through increasing ocean acidity and rising temperatures. We focus on intertidal rocky shores of temperate seas as model systems, acknowledging the longstanding role of these communities in deciphering ecological principles. Our survey illustrates the …


Genome-Wide Snps Resolve Spatiotemporal Patterns Of Connectivity Within Striped Marlin (Kajikia Audax), A Broadly Distributed And Highly Migratory Pelagic Species, Nadya Mamoozadeh, John Graves, Jan Mcdowell Jan 2019

Genome-Wide Snps Resolve Spatiotemporal Patterns Of Connectivity Within Striped Marlin (Kajikia Audax), A Broadly Distributed And Highly Migratory Pelagic Species, Nadya Mamoozadeh, John Graves, Jan Mcdowell

VIMS Articles

Genomic methodologies offer unprecedented opportunities for statistically robust studies of species broadly distributed in environments conducive to high gene flow, providing valuable information for wildlife conservation and management. Here, we sequence restriction site‐associated DNA to characterize genome‐wide single nucleotide polymorphisms (SNPs) in a broadly distributed and highly migratory large pelagic fish, striped marlin (Kajikia audax). Assessment of over 4,000 SNPs resolved spatiotemporal patterns of genetic connectivity throughout the species range in the Pacific and, for the first time, Indian oceans. Individual‐based cluster analyses identified six genetically distinct populations corresponding with the western Indian, eastern Indian, western South Pacific, …


Climate Change Enhances Disease Processes In Crustaceans: Case Studies In Lobsters, Crabs, And Shrimps, Jeffrey D. Shields Jan 2019

Climate Change Enhances Disease Processes In Crustaceans: Case Studies In Lobsters, Crabs, And Shrimps, Jeffrey D. Shields

VIMS Articles

Climate change has resulted in increasing temperature and acidification in marine systems. Rising temperature and acidification act as stressors that negatively affect host barriers to infection, thus enhancing disease processes and influencing the emergence of pathogens in ecologically and commercially important species. Given that crustaceans are ectotherms, changes in temperature dominate their physiological and immunological responses to microbial pathogens and parasites. Because of this, the thermal ranges of several crustacean hosts and their pathogens can be used to project the outcomes of infections. Host factors such as molting, maturation, respiration, and immune function are strongly influenced by temperature, which in …