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Abstracts Of Technical Papers Presented At The 103rd Annual Meeting National Shellfisheries Association Baltimore, Maryland March 27–31, 2011, National Shellfisheries Association
Abstracts Of Technical Papers Presented At The 103rd Annual Meeting National Shellfisheries Association Baltimore, Maryland March 27–31, 2011, National Shellfisheries Association
VIMS Articles
No abstract provided.
Jellyfish Blooms Result In A Major Microbial Respiratory Sink Of Carbon In Marine Systems, Robert H. Condon, Deborah K. Steinberg, Paul Del Giorgio, Thierry Bouvier, Deborah A. Bronk, William Graham, Hugh W. Ducklow
Jellyfish Blooms Result In A Major Microbial Respiratory Sink Of Carbon In Marine Systems, Robert H. Condon, Deborah K. Steinberg, Paul Del Giorgio, Thierry Bouvier, Deborah A. Bronk, William Graham, Hugh W. Ducklow
VIMS Articles
Jellyfish blooms occur in many estuarine and coastal regions and may be increasing in their magnitude and extent worldwide. Voracious jellyfish predation impacts food webs by converting large quantities of carbon (C), fixed by primary producers and consumed by secondary producers, into gelatinous biomass, which restricts C transfer to higher trophic levels because jellyfish are not readily consumed by other predators. In addition, jellyfish release colloidal and dissolved organic matter (jelly-DOM), and could further influence the functioning of coastal systems by altering microbial nutrient and DOM pathways, yet the links between jellyfish and bacterioplankton metabolism and community structure are unknown. …
The Functional Role Of Producer Diversity In Ecosystems, Bradley J. Cardinale, Kristin L. Matulich, David U. Hooper, Jarrett E. K. Byrnes, Emmett J. Duffy, Lars Gamfeldt, Patricia Balvanera, Mary I. O'Connor, Andrew Gonzalez
The Functional Role Of Producer Diversity In Ecosystems, Bradley J. Cardinale, Kristin L. Matulich, David U. Hooper, Jarrett E. K. Byrnes, Emmett J. Duffy, Lars Gamfeldt, Patricia Balvanera, Mary I. O'Connor, Andrew Gonzalez
VIMS Articles
Over the past several decades, a rapidly expanding field of research known as biodiversity and ecosystem functioning has begun to quantify how the world's biological diversity can, as an independent variable, control ecological processes that are both essential for, and fundamental to, the functioning of ecosystems. Research in this area has often been justified on grounds that (1) loss of biological diversity ranks among the most pronounced changes to the global environment and that (2) reductions in diversity, and corresponding changes in species composition, could alter important services that ecosystems provide to humanity (e.g., food production, pest/disease control, water purification). …
Oyster Reefs At Risk And Recommendations For Conservation, Restoration, And Management, Michael W. Beck, Robert D. Brumbaugh, Laura Airoldi, Alvar Carranza, Loren D. Coen, Christine Crawford, Omar Defeo, Graham J. Edgar, Boze Handcock, Matthew C. Kay, Hunter S. Lenihan, Mark Luckenbach, Caitlyn L. Toropova, Guofan Zhang, Ximing Guo
Oyster Reefs At Risk And Recommendations For Conservation, Restoration, And Management, Michael W. Beck, Robert D. Brumbaugh, Laura Airoldi, Alvar Carranza, Loren D. Coen, Christine Crawford, Omar Defeo, Graham J. Edgar, Boze Handcock, Matthew C. Kay, Hunter S. Lenihan, Mark Luckenbach, Caitlyn L. Toropova, Guofan Zhang, Ximing Guo
VIMS Articles
Native oyster reefs once dominated many estuaries, ecologically and economically. Centuries of resource extraction exacerbated by coastal degradation have pushed oyster reefs to the brink of functional extinction worldwide. We examined the condition of oyster reefs across 144 bays and 44 ecoregions; our comparisons of past with present abundances indicate that more than 90% of them have been lost in bays (70%) and ecoregions (63%). In many bays, more than 99% of oyster reefs have been lost and are functionally extinct. Overall, we estimate that 85% of oyster reefs have been lost globally. Most of the world's remaining wild capture …
Linked Indicator Sets For Addressing Biodiversity Loss, Th Sparks, Shm Butchart, A Balmford, L Bennun, D Stanwell-Smith, R. J. Diaz, Et Al.
Linked Indicator Sets For Addressing Biodiversity Loss, Th Sparks, Shm Butchart, A Balmford, L Bennun, D Stanwell-Smith, R. J. Diaz, Et Al.
VIMS Articles
The target adopted by world leaders of significantly reducing the rate of biodiversity loss by 2010 was not met but this stimulated a new suite of biodiversity targets for 2020 adopted by the Parties to the Convention on Biological Diversity (CBD) in October 2010. Indicators will be essential for monitoring progress towards these targets and the CBD will be defining a suite of relevant indicators, building on those developed for the 2010 target. Here we argue that explicitly linked sets of indicators offer a more useful framework than do individual indicators because the former are easier to understand, communicate and …
A General Equilibrium Model For Atlantic Herring (Clupea Harengus) With Ecosystem Considerations, Je Kirkley, J Walden, R Fare
A General Equilibrium Model For Atlantic Herring (Clupea Harengus) With Ecosystem Considerations, Je Kirkley, J Walden, R Fare
VIMS Articles
A framework is presented for assessing the economic ramifications of ecosystem-based management decisions, with attention focused on Atlantic herring (Clupea harengus) in New England. The Atlantic herring has often been referred to as the most important fish in the northeastern United States because it is a filter-feeder, is believed to improve water quality, and is very important to the health, growth, and abundance of major gamefish, marine mammals, seabirds, and several species of fish. Although many approaches for examining the potential economic ramifications of ecosystem-based management are possible, attention is focused on one method that can be used given existing …
Copepod Guts As Biogeochemical Hotspots In The Sea: Evidence From Microelectrode Profiling Of Calanus Spp., Kw Tang, Rn Glud, A Glud, S Rysgaard, Tg Nielsen
Copepod Guts As Biogeochemical Hotspots In The Sea: Evidence From Microelectrode Profiling Of Calanus Spp., Kw Tang, Rn Glud, A Glud, S Rysgaard, Tg Nielsen
VIMS Articles
The environmental conditions inside the gut of Calanus hyperboreus and C. glacialis were measured with microelectrodes. An acidic potential hydrogen (pH) gradient was present in the gut of C. hyperboreus, and the lowest pH recorded was 5.40. The gut pH of a starved copepod decreased by 0.53 after the copepod resumed feeding for a few hours, indicating the secretion of acidic digestive fluid. A copepod feeding on Thalassiosira weissflogii (diatom) had slightly lower pH than that feeding on Rhodomonas salina (cryptophyte). Oxygen was undersaturated in the gut of both C. hyperboreus and C. glacialis, with a steep gradient from the …
Metazooplankton Community Structure, Feeding Rate Estimates, And Hydrography In A Meltwater-Influenced Greenlandic Fjord, Kam W. Tang, Torkel Gissel Nielsen, Peter Munk, John Mortensen
Metazooplankton Community Structure, Feeding Rate Estimates, And Hydrography In A Meltwater-Influenced Greenlandic Fjord, Kam W. Tang, Torkel Gissel Nielsen, Peter Munk, John Mortensen
VIMS Articles
In order to assess the potential responses of Greenland's coastal ecosystems to future climate change, we studied the hydrography and distribution of metazooplankton, along a transect from the slope waters beyond Fyllas Banke to the inner part of Godthabsfjord, West Greenland, in July and August 2008, and estimated feeding rates for some of the larger species groups. Within the 4 regional domains that were covered in the study (continental slope, continental shelf, outer sill region, and main fjord basin), salty coastal water and glacial runoff mixed to various extents, and 7 water masses with specific characteristics were identified. The common …
Vertical Structure, Seasonal Drawdown, And Net Community Production In The Ross Sea, Antarctica, Matthew C. Long, Robert B. Dunbar, Philippe D. Tortell, Walker O. Smith Jr., David A. Mucciarone, Giacomo R. Ditullio
Vertical Structure, Seasonal Drawdown, And Net Community Production In The Ross Sea, Antarctica, Matthew C. Long, Robert B. Dunbar, Philippe D. Tortell, Walker O. Smith Jr., David A. Mucciarone, Giacomo R. Ditullio
VIMS Articles
We calculate net community production (NCP) during summer 2005-2006 and spring 2006 in the Ross Sea using multiple approaches to determine the magnitude and consistency of rates. Water column carbon and nutrient inventories and surface ocean O-2/Ar data are compared to satellite-derived primary productivity (PP) estimates and C-14 uptake experiments. In spring, NCP was related to stratification proximal to upper ocean fronts. In summer, the most intense C drawdown was in shallow mixed layers affected by ice melt; depth-integrated C drawdown, however, increased with mixing depth. Delta O-2/Ar-based methods, relying on gas exchange reconstructions, underestimate NCP due to seasonal variations …
Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, P. N. Sedwick, Walker O. Smith Jr.
Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, P. N. Sedwick, Walker O. Smith Jr.
VIMS Articles
The Ross Sea polynya is among the most productive regions in the Southern Ocean and may constitute a significant oceanic CO2 sink. Based on results from several field studies, this region has been considered seasonally iron limited, whereby a "winter reserve" of dissolved iron (dFe) is progressively depleted during the growing season to low concentrations (similar to 0.1 nM) that limit phytoplankton growth in the austral summer (December-February). Here we report new iron data for the Ross Sea polynya during austral summer 2005-2006 (27 December-22 January) and the following austral spring 2006 (16 November-3 December). The summer 2005-2006 data show …
Food Chain Length And Omnivory Determine The Stability Of A Marine Subtidal Food Web, Zt Long, Jf Bruno, Je Duffy
Food Chain Length And Omnivory Determine The Stability Of A Marine Subtidal Food Web, Zt Long, Jf Bruno, Je Duffy
VIMS Articles
P>1. Using a subtidal marine food web as a model system, we examined how food chain length (predators present or absent) and the prevalence of omnivory influenced temporal stability (and its components) of herbivores and plants. We held the density of top predators constant but manipulated their identity to generate a gradient in omnivory prevalence. 2. We measured temporal stability as the inverse of the coefficient of variation of abundance over time. Predators and omnivory could influence temporal stability through effects on abundance (the 'abundance' effect), summed variance across taxa (the 'portfolio effect') or summed covariances among taxa (the …
An Evaluation Of Ocean Color Model Estimates Of Marine Primary Productivity In Coastal And Pelagic Regions Across The Globe, V. S. Saba, Marjorie A.M. Friedrichs, Walker O. Smith Jr.
An Evaluation Of Ocean Color Model Estimates Of Marine Primary Productivity In Coastal And Pelagic Regions Across The Globe, V. S. Saba, Marjorie A.M. Friedrichs, Walker O. Smith Jr.
VIMS Articles
Nearly half of the earth's photosynthetically fixed carbon derives from the oceans. To determine global and region specific rates, we rely on models that estimate marine net primary productivity (NPP) thus it is essential that these models are evaluated to determine their accuracy. Here we assessed the skill of 21 ocean color models by comparing their estimates of depth-integrated NPP to 1156 in situ C-14 measurements encompassing ten marine regions including the Sargasso Sea, pelagic North Atlantic, coastal Northeast Atlantic, Black Sea, Mediterranean Sea, Arabian Sea, subtropical North Pacific, Ross Sea, West Antarctic Peninsula, and the Antarctic Polar Frontal Zone. …
Non-Consumptive Predator Effects Indirectly Influence Marine Plant Biomass And Palatability, Pl Reynolds, Ee Sotka
Non-Consumptive Predator Effects Indirectly Influence Marine Plant Biomass And Palatability, Pl Reynolds, Ee Sotka
VIMS Articles
1. Predators can reduce herbivory and increase plant biomass by consuming herbivores, lowering individual herbivore feeding rates, or both. We tested whether the presence of predators increases plant quality by non-consumptively reducing grazing pressure and thereby weakening the strength of the induced response in plant chemical defences. 2. We performed a 42-day outdoor mesocosm experiment in which the herbivorous amphipod Ampithoe longimana was cultured on the brown seaweed Sargassum filipendula in the presence and absence of olfactory cues of its principal fish predator, the pinfish Lagodon rhomboides. The presence of fish cues reduced per capita rates of amphipod grazing by …
Multi-Locus Phylogeny Of Sponge-Dwelling Snapping Shrimp (Caridea: Alpheidae: Synalpheus) Supports Morphology-Based Species Concepts, Km Hultgren, Je Duffy
Multi-Locus Phylogeny Of Sponge-Dwelling Snapping Shrimp (Caridea: Alpheidae: Synalpheus) Supports Morphology-Based Species Concepts, Km Hultgren, Je Duffy
VIMS Articles
Alpheid snapping shrimp are one of the most diverse groups of coral-reef fauna, and sponge-dwelling shrimp in the genus Synalpheus (gambarelloides species group) have in particular become a model system for studying the evolution of social biology and host use in marine invertebrates. Despite recent advances in understanding the evolution and systematics of Synalpheus, the taxonomy and phylogenetic relationships within this group remain challenging. More than 20 new species in the S. gambarelloides species group have been described over the past two decades, primarily within several cryptic species complexes, which has doubled the known diversity of this group …
Antarctic Sea Ice Carbon Dioxide System And Controls, Virginia Institute Of Marine Science, Agneta Fransson, Melissa Chierici, Patricia L. Yager, Walker O. Smith Jr.
Antarctic Sea Ice Carbon Dioxide System And Controls, Virginia Institute Of Marine Science, Agneta Fransson, Melissa Chierici, Patricia L. Yager, Walker O. Smith Jr.
VIMS Articles
In austral summer, from December 2008 to January 2009, we investigated the sea-ice carbon dioxide (CO(2)) system and CO(2) controls in the Amundsen and Ross Seas, Antarctica. We sampled seawater, brine and sea ice for the measurements of total alkalinity (A(T)), total inorganic carbon (DIC), pH, inorganic nutrients, particulate organic carbon (POC) and nitrogen (PON), chlorophyll a, pigments, salinity and temperature. Large variability in all measured parameters was observed in time and space due to the complex sea-ice dynamics. We discuss the controls of the sea-ice CO(2) system, such as brine rejection, biological processes, calcium carbonate (CaCO(3)) precipitation/dissolution and CO(2) …
Diet Selectivity Of Juvenile Blue Crabs (Callinectes Sapidus) In Chesapeake Bay, Rochelle D. Seitz, Ke Knick, M Westphal
Diet Selectivity Of Juvenile Blue Crabs (Callinectes Sapidus) In Chesapeake Bay, Rochelle D. Seitz, Ke Knick, M Westphal
VIMS Articles
Shallow coves in Chesapeake Bay have abundant food and serve as nursery grounds for juvenile blue crabs. In this study, we examined the relationships between the diet of very small (4-40 mm CW) juvenile blue crabs and the benthic infauna in shallow, unvegetated nursery coves. We compared infauna in benthic samples with gut contents of juvenile blue crabs from six shallow coves in each of two sub-estuaries (Rappahannock and York Rivers) in Chesapeake Bay, Virginia, USA. Benthic communities differed depending on river and location, with abundant clams in upriver regions and abundant polychaetes in downriver regions. Juvenile crabs, like adults, …
Population Structure Of A Deep-Water Squaloid Shark, The Portuguese Dogfish (Centroscymnus Coelolepis), A Verissimo, Jan Mcdowell, John Graves
Population Structure Of A Deep-Water Squaloid Shark, The Portuguese Dogfish (Centroscymnus Coelolepis), A Verissimo, Jan Mcdowell, John Graves
VIMS Articles
The genetic population structure of the deep-water squaloid Centroscymnus coelolepis (the Portuguese dogfish) in the eastern Atlantic was investigated using eight polymorphic nuclear microsatellite markers and a 496-bp fragment of the mitochondrial DNA control region (mtDNA CR). Samples (20-50 individuals per location) were collected off Ireland, Portugal, Madeira, Mauritania, South Africa, and the Azores (Mid-Atlantic Ridge). High levels of genetic diversity were found at the nuclear microsatellite loci (mean A = 17.3; overall H(o) = 0.77), although there was low diversity at the mtDNA CR (h = 0.65, pi = 0 0.0018). Genetic diversity for the Portuguese dogfish was homogeneously …
The Role Of Nitrogen On The Growth And Colony Development Of Phaeocystis Globosa (Prymnesiophyceae), Xd Wang, Y Wang, Walker O. Smith Jr.
The Role Of Nitrogen On The Growth And Colony Development Of Phaeocystis Globosa (Prymnesiophyceae), Xd Wang, Y Wang, Walker O. Smith Jr.
VIMS Articles
The effects of nitrate, ammonium and urea on the growth and colony formation of three strains of Phaeocystis globosa were investigated. Although ammonium and urea supported growth, nitrate was the favoured nitrogen source for the growth of solitary cells for all three strains. Phaeocystis globosa CCMP 1528 and 629 formed colonies in all cultures where nitrate was the sole nitrogen source, but only a few colonies were observed in ammonium and urea treatments. Ammonium and urea were far less effective in supporting growth, biomass generation and colony formation in all three strains. Once colonies developed, colonial cells accounted for at …