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VIMS Articles

2006

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Articles 1 - 30 of 41

Full-Text Articles in Life Sciences

Wild And Aquaculture Populations Of The Eastern Oyster Compared Using Microsatellites, J Carlsson, Cl Morrison, Kimberly S. Reece Dec 2006

Wild And Aquaculture Populations Of The Eastern Oyster Compared Using Microsatellites, J Carlsson, Cl Morrison, Kimberly S. Reece

VIMS Articles

Five new microsatellite markers were developed for the eastern oyster (Crassostrea virginica), and allelic variability was compared between a wild Chesapeake Bay population (James River) and a hatchery strain (DEBY (TM)). All loci amplified readily and demonstrated allelic variability with the number of alleles ranging from 16 to 36 in the wild population and from 11 to 19 in the DEBY (TM) strain. Average observed and expected heterozygosities were estimated at 0.66 and 0.80 in the hatchery sample. The corresponding estimates were 0.91 and 0.75 in the wild sample. Results indicated lower genetic variability in the ...


Marine Pelagic Ecosystems: The West Antarctic Peninsula, Hugh Ducklow, Karen Baker, Douglas G. Martinson, Langdon B. Quetin, Robin M. Ross, Raymond C. Smith, Sharon E. Stammerjohn, Maria Vernet, William R. Fraser Nov 2006

Marine Pelagic Ecosystems: The West Antarctic Peninsula, Hugh Ducklow, Karen Baker, Douglas G. Martinson, Langdon B. Quetin, Robin M. Ross, Raymond C. Smith, Sharon E. Stammerjohn, Maria Vernet, William R. Fraser

VIMS Articles

The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the ...


Genetic Analysis Of White Marlin (Tetrapturus Albidus) Stock Structure, John Graves, Jan Mcdowell Nov 2006

Genetic Analysis Of White Marlin (Tetrapturus Albidus) Stock Structure, John Graves, Jan Mcdowell

VIMS Articles

The genetic basis of stock structure of white marlin (Tetrapturus albidus Poey, 1860) was inferred from analyses of five tetranucleotide repeat microsatellite loci (n = 214) and the mitochondrial (mt)DNA control region (n = 99) of white marlin from four geographic regions in the Atlantic Ocean. Considerable genetic variation was present in all collections for all molecular markers. Analysis of replicate collections taken in different years from three regions revealed no significant differences in the distribution of allele frequencies among years within regions. The value of global F-statistics for both multilocus microsatellite data and mtDNA control region sequences approached significance (0 ...


Globally Distributed Mycobacterial Fish Pathogens Produce A Novel Plasmid-Encoded Toxic Macrolide, Mycolactone F, B S. Ranger, E A. Malone, L Mosi, S Adusumilli, R E. Lee, A Coloni, M Rhodes, Plc Small Nov 2006

Globally Distributed Mycobacterial Fish Pathogens Produce A Novel Plasmid-Encoded Toxic Macrolide, Mycolactone F, B S. Ranger, E A. Malone, L Mosi, S Adusumilli, R E. Lee, A Coloni, M Rhodes, Plc Small

VIMS Articles

Mycobacterium ulcerans and Mycobacterium marinum are closely related pathogens which share an aquatic environment. The pathogenesis of these organisms in humans is limited by their inability to grow above 35 degrees C. M. marinum causes systemic disease in fish but produces localized skin infections in humans. M. ulcerans causes Burulli ulcer, a severe human skin lesion. At the molecular level, M. ulcerans is distinguished from M. marinum by the presence of a virulence plasmid which encodes a macrolide toxin, mycolactone, as well as by hundreds of insertion sequences, particularly IS2404. There has been a global increase in reports of fish ...


Microbial Abundance, Composition And Enzymatic Activity During Decomposition Of Copepod Carcasses, Kw Tang, Kml Hutalle, Et Al Nov 2006

Microbial Abundance, Composition And Enzymatic Activity During Decomposition Of Copepod Carcasses, Kw Tang, Kml Hutalle, Et Al

VIMS Articles

Literature suggests that zooplankton carcasses are prevalent at times in both freshwater and marine environments, and could be important substrate sources for water column microbes (Dubovskaya et al. 2003, Hydrobiologia 504:223-227; Tang et al. 2006b, Estuar Coast Shelf Sci 68:499-508). We conducted laboratory experiments to investigate the decomposition of copepod carcasses by ambient microbes from Lake Dagow, Germany. Bacteria rapidly colonized and decomposed the carcasses, mainly from the inside. The ambient bacterial abundance increased 2-fold or more at the peak of decomposition, but decreased afterward, presumably due to protozoan grazing. Initial increase in ambient bacteria was faster at ...


Comparison Of Cell‐Specific Activity Between Free‐Living And Attached Bacteria Using Isolates And Natural Assemblages, Hans-Peter Grossart, Kam W. Tang, Thomas Kiorboe, Helle Ploug Nov 2006

Comparison Of Cell‐Specific Activity Between Free‐Living And Attached Bacteria Using Isolates And Natural Assemblages, Hans-Peter Grossart, Kam W. Tang, Thomas Kiorboe, Helle Ploug

VIMS Articles

Marine snow aggregates are microbial hotspots that support high bacterial abundance and activities. We conducted laboratory experiments to compare cell‐specific bacterial protein production (BPP) and protease activity between free‐living and attached bacteria. Natural bacterial assemblages attached to model aggregates (agar spheres) had threefold higher BPP and two orders of magnitude higher protease activity than their free‐living counterpart. These observations could be explained by preferential colonization of the agar spheres by bacteria with inherently higher metabolic activity and/or individual bacteria increasing their metabolism upon attachment to surfaces. In subsequent experiments, we used four strains of marine snow ...


Phylogeny Of Recent Billfishes (Xiphioidei), Bb Collette, Jan Mcdowell, John Graves Oct 2006

Phylogeny Of Recent Billfishes (Xiphioidei), Bb Collette, Jan Mcdowell, John Graves

VIMS Articles

Billfishes are genetically and morphologically distinct enough from scombroids to merit placement in a separate suborder, Xiphioidei. Two extant families are usually recognized: Xiphiidae (swordfish, Xiphias) and Istiophoridae, currently containing three genera, Istiophorus (sailfishes), Makaira (marlins), and Tetrapturus (spearfishes, white, and striped marlins). Phylogenetic analyses of molecular data from mitochondrial and nuclear gene sequences (mitochondrial control region, ND2, 12S, and nuclear MN 32 regions) show a different picture of relationships. Makaira is not monophyletic: blue marlin cluster with sailfish and placement of black marlin is unstable. Accepting the molecular phylogeny gives two possible classifications: (1) two genera: blue marlin + sailfish ...


Detection Of Panulirus Argus Virus 1 (Pav1) In The Caribbean Spiny Lobster Using Fluorescence In Situ Hybridization (Fish), Cw Li, Jeffrey D. Shields, Hamish J. Small, Kimberly S. Reece, Et Al Sep 2006

Detection Of Panulirus Argus Virus 1 (Pav1) In The Caribbean Spiny Lobster Using Fluorescence In Situ Hybridization (Fish), Cw Li, Jeffrey D. Shields, Hamish J. Small, Kimberly S. Reece, Et Al

VIMS Articles

Panulirus argus Virus 1 (PaV1) is the first virus known to be pathogenic to a wild lobster. It infects the Caribbean spiny lobster P. argus from the Florida Keys, and has a predilection for juveniles. The monitoring of the virus in wild populations and study of its behavior in the laboratory require the development of reliable diagnostic tools. A sensitive and specific fluorescence in situ hybridization (FISH) assay was developed for detection of PaV1. The lower detection limit using a 110 bp DNA probe in a dot-blot hybridization for PaV1 DNA was 10 pg of cloned template PaV1 DNA and ...


Viability, Infectivity And Fatty Acid Synthetic Activity Of Perkinsus Marinus Meront Cells Incubated In Estuarine And Artificial Seawater, Fle Chu, Ed Lund Jul 2006

Viability, Infectivity And Fatty Acid Synthetic Activity Of Perkinsus Marinus Meront Cells Incubated In Estuarine And Artificial Seawater, Fle Chu, Ed Lund

VIMS Articles

We investigated the viability and fatty acid synthetic activity of in vitro cultured Perkinsus marinus (Dermo) in lipid-free medium and estuarine water, and the infectivity of P. marinus maintained in artificial seawater (ASW). Viability and fatty acid synthetic activity in 7 d old R marinus meronts maintained in lipid-free medium and estuarine water were tested. The infectivity of meronts incubated in ASW was examined by first incubating P. marinus meronts in ASW for 2, 3 or 7 d, and then inoculating viable ASW-incubated meronts into the shell cavity of individual oysters Crassostrea virginica. P. marinus infection prevalence and intensity in ...


Genetic Heterogeneity Of Atlantic Bluefin Tuna Caught In The Eastern North Atlantic Ocean South Of Iceland, J Carlsson, Jr Mcdowell, Et Al Jul 2006

Genetic Heterogeneity Of Atlantic Bluefin Tuna Caught In The Eastern North Atlantic Ocean South Of Iceland, J Carlsson, Jr Mcdowell, Et Al

VIMS Articles

Atlantic bluefin tuna (Thunnus thynnus) are currently managed by the member nations of the International Commission for the Conservation of Atlantic Tunas (ICCAT) as distinct western and eastern stocks, separated by the 45 degrees W meridian. Previous studies of Atlantic bluefin tuna caught in the northeast Atlantic south of Nor-way suggested mixing of putative stocks in the region, based on abrupt shifts in the size and condition of fish during the fishing season. By contrast, more recent studies south of Iceland reported only small differences in size of tuna caught at different times of the season in that area. To ...


Incentive-Based Approaches To Sustainable Fisheries, Rq Grafton, R Arnason, Et Al, Je Kirkley, Et Al Mar 2006

Incentive-Based Approaches To Sustainable Fisheries, Rq Grafton, R Arnason, Et Al, Je Kirkley, Et Al

VIMS Articles

The failures of traditional target-species management have led many to propose an ecosystem approach to fisheries to promote sustainability. The ecosystem approach is necessary, especially to account for fishery-ecosystem interactions, but by itself is not sufficient to address two important factors contributing to unsustainable fisheries: inappropriate incentives bearing on fishers and the ineffective governance that frequently exists in commercial, developed fisheries managed primarily by total-harvest limits and input controls. We contend that much greater emphasis must be placed on fisher motivation when managing fisheries. Using evidence from more than a dozen natural experiments in commercial fisheries, we argue that incentive-based ...


Biodiversity, Host Specificity, And Dominance By Eusocial Species Among Sponge-Dwelling Alpheid Shrimp On The Belize Barrier Reef, Kenneth S. Macdonald Iii, Ruben Rios, J. Emmett Duffy Mar 2006

Biodiversity, Host Specificity, And Dominance By Eusocial Species Among Sponge-Dwelling Alpheid Shrimp On The Belize Barrier Reef, Kenneth S. Macdonald Iii, Ruben Rios, J. Emmett Duffy

VIMS Articles

Alpheid shrimp represent an abundant and diverse, but poorly characterized, component of the cryptic biodiversity of coral reefs worldwide. Sponge-inhabiting alpheids provide a promising model system for exploring patterns of cryptic reef biodiversity because their habitats (hosts) are discrete and qualitatively distinct units. We tabulated data from 14 years of collections at Carrie Bow Cay, Belize to quantify patterns of diversity, host specificity, and dominance among sponge-dwelling shrimp (Synalpheus), with special attention to eusocial species. From > 600 sampled sponges of 17 species, we recognized at least 36 Synalpheus shrimp species. Of these, 15 (42%) were new to science. Species accumulation ...


Molecular Assays For Detecting Aphanomyces Invadans In Ulcerative Mycotic Fish Lesions, Mw Vandersea, Rw Litaker, B Yonnish,, Et Al, H Kator, Et Al Feb 2006

Molecular Assays For Detecting Aphanomyces Invadans In Ulcerative Mycotic Fish Lesions, Mw Vandersea, Rw Litaker, B Yonnish,, Et Al, H Kator, Et Al

VIMS Articles

The pathogenic oomycete Aphanomyces invadans is the primary etiological agent in ulcerative mycosis, an ulcerative skin disease caused by a fungus-like agent of wild and cultured fish. We developed sensitive PCR and fluorescent peptide nucleic acid in situ hybridization (FISH) assays to detect A. invadans. Laboratory-challenged killifish (Fundulus heteroclitus) were first tested to optimize and validate the assays. Skin ulcers of Atlantic menhaden (Brevoortia tyrannus) from populations found in the Pamlico and Neuse River estuaries in North Carolina were then surveyed. Results from both assays indicated that all of the lesioned menhaden (n = 50) collected in September 2004 were positive ...


Interactions Between Marine Snow And Heterotrophic Bacteria: Aggregate Formation And Microbial Dynamics, Hp Grossart, T Kiorboe, Kw Tang, Et Al Feb 2006

Interactions Between Marine Snow And Heterotrophic Bacteria: Aggregate Formation And Microbial Dynamics, Hp Grossart, T Kiorboe, Kw Tang, Et Al

VIMS Articles

Macroscopic aggregates (marine snow) contribute to new production and nutrient dynamics in the upper ocean and vertical fluxes of organic matter to the deep ocean. To test whether microorganisms play a significant role in phytoplankton aggregate formation we studied particle abundance and size as well as abundance, colonization behaviour, and community composition of bacteria during the growth of 2 marine diatoms (Thalassiosira weissflogii and Navicula sp.) under axenic and non-axenic conditions. Community composition of free-living and attached bacteria during phytoplankton growth and aggregation was studied by amplification of 16S rRNA gene fragments and denaturing gradient gel electrophoresis (DGGE). Our results ...


Evaluation Of A Lifetime‐Based Optode To Measure Oxygen In Aquatic Systems, Anders Tengberg, Jostein Hovdenes, Henrik J. Andersson, Olivier Brocandel, Robert J. Diaz, David Hebert, Tony Arnerich, Christian Huber, Arne Kortzinger, Alexis Khripounoff, Francisco Rey, Christer Ronning, Jens Schimanski, Stefan Sommer, Achim Stangelmayer Feb 2006

Evaluation Of A Lifetime‐Based Optode To Measure Oxygen In Aquatic Systems, Anders Tengberg, Jostein Hovdenes, Henrik J. Andersson, Olivier Brocandel, Robert J. Diaz, David Hebert, Tony Arnerich, Christian Huber, Arne Kortzinger, Alexis Khripounoff, Francisco Rey, Christer Ronning, Jens Schimanski, Stefan Sommer, Achim Stangelmayer

VIMS Articles

In this article, we evaluate the performance of a commercially available lifetime‐based optode and compare it with data obtained by other methods. We performed a set of 10 different tests, including targeted laboratory evaluations and field studies, covering a wide range of situations from shallow coastal waters and wastewater treatment plants to abyssal depths. Our principal conclusion is that, owing to high accuracy (± 2 µM), long‐term stability (more than 20 months), lack of pressure hysteresis, and limited cross‐sensitivity, this method is overall more suitable for oxygen monitoring than other methods.


Out-Crossing Among Commercial Strains Of The Northern Quahog, Mercenaria Mercenaria: Survival, Growth And Implications For Selective Breeding, Md Camara, Standish K. Allen Jr., Ryan Carnegie, Kimberly S. Reece Jan 2006

Out-Crossing Among Commercial Strains Of The Northern Quahog, Mercenaria Mercenaria: Survival, Growth And Implications For Selective Breeding, Md Camara, Standish K. Allen Jr., Ryan Carnegie, Kimberly S. Reece

VIMS Articles

Because the accumulation of inbreeding within hatchery-propagated stocks of the hard clam, Mercenaria mercenaria (Linnaeus, 1758), could result in reduced growth and survival, we studied the potential for improving performance through out-crossing among existing hatchery strains. We produced all 10 possible out-crossed combinations among 5 strains of clams as well as all 5 pure parental strains simultaneously in the hatchery and measured their size at the time of metamorphosis (the spat stage) and at the end of a nursery period in mesh bags at a single field site (the seed stage). We then planted replicate plots of all fifteen strains ...


Estimating Consumption Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Chesapeake Bay, Virginia, Using A Bioenergetics Model, W Wesley Dowd, Richard Brill, Peter Bushnell, John A. Musick Jan 2006

Estimating Consumption Rates Of Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Chesapeake Bay, Virginia, Using A Bioenergetics Model, W Wesley Dowd, Richard Brill, Peter Bushnell, John A. Musick

VIMS Articles

Using a bioenergetics model, we estimated daily ration and seasonal prey consumption rates for six age classes of juvenile sandbar sharks (Carcharhinus plumbeus) in the lower Chesapeake Bay summer nursery area. The model, incorporating habitat and species-specific data on growth rates, metabolic rate, diet composition, water temperature (range 16.8-27.9 degrees C), and population structure, predicted mean daily rations between 2.17 +/- 0.03 (age-0) and 1.30 +/- 0.02 (age-5) % body mass/day. These daily rations are higher than earlier predictions for sandbar sharks but are comparable to those for ecologically similar shark species. The total nursery population ...


Survival Of White Marlin (Tetrapturus Albidus) Released From Commercial Pelagic Longline Gear In The Western North Atlantic, David Kerstetter, John E. Graves Jan 2006

Survival Of White Marlin (Tetrapturus Albidus) Released From Commercial Pelagic Longline Gear In The Western North Atlantic, David Kerstetter, John E. Graves

VIMS Articles

To estimate postrelease survival of white marlin (Tetrapturus albidus) caught incidentally in regular commercial pelagic longline fishing operations targeting swordfish and tunas, short-duration popup satellite archival tags (PSATs) were deployed on captured animals for periods of 5-43 days. Twenty (71.4%) of 28 tags transmitted data at the preprogrammed time, including one tag that separated from the fish shortly after release and was omitted from subsequent analyses. Transmitted data from 17 of 19 tags were consistent with survival of those animals for the duration of the tag deployment. Postrelease survival estimates ranged from 63.0% (assuming all nontransmitting tags were ...


Growth And Maturity Of Salmon Sharks (Lamna Ditropis) In The Eastern And Western North Pacific, And Comments On Back-Calculation Methods, Kenneth J. Goldman, John A. Musick Jan 2006

Growth And Maturity Of Salmon Sharks (Lamna Ditropis) In The Eastern And Western North Pacific, And Comments On Back-Calculation Methods, Kenneth J. Goldman, John A. Musick

VIMS Articles

Age and growth estimates for salmon sharks (Lamna ditropis) in the eastern North Pacific were derived from 182 vertebral centra collected from sharks ranging in length from 62.2 to 213.4 cm precaudal length (PCL) and compared to previously published age and growth data for salmon sharks in the western North Pacific. Eastern North Pacific female and male salmon sharks were aged up to 20 and 17 years, respectively. Relative marginal increment (RMI) analysis showed that postnatal rings form annually between January and March. Von Bertalanffy growth parameters derived from vertebral length-at-age data are L-proportional to=207.4 cm ...


Fish Assemblages Found In Tidal-Creek And Seagrass Habitats In The Suwannee River Estuary, Troy D. Tuckey, Mark Dehaven Jan 2006

Fish Assemblages Found In Tidal-Creek And Seagrass Habitats In The Suwannee River Estuary, Troy D. Tuckey, Mark Dehaven

VIMS Articles

Fish assemblages were investigated in tidal-creek and seagrass habitats in the Suwannee River estuary, Florida. A total of 91,571 fish representing 43 families were collected in monthly seine samples from January 1997 to December 1999. Tidal creeks supported greater densities of fish (3.89 fish/m(2); 83% of total) than did seagrass habitats (0.93 fish/m(2)). We identified three distinct fish assemblages in each habitat: winter-spring, summer, and fall. Pinfish (Lagodon rhomboides), pigfish (Orthopristis chrysoptera), and syngnathids characterized seagrass assemblages, whereas spot (Leiostomus xanthurus), bay anchovy (Anchoa mitchilli), silversides (Menidia spp.), mojarras (Eucinostomus spp.), and fundulids ...


Influence Of Shallow-Water Habitats And Shoreline Development On Abundance, Biomass, And Diversity Of Benthic Prey And Predators In Chesapeake Bay, Rd Seitz, Rom Lipcius, N. H. Olmstead, M. S. Seebo Jan 2006

Influence Of Shallow-Water Habitats And Shoreline Development On Abundance, Biomass, And Diversity Of Benthic Prey And Predators In Chesapeake Bay, Rd Seitz, Rom Lipcius, N. H. Olmstead, M. S. Seebo

VIMS Articles

Within the coastal zone, waterfront development has caused severe loss of shallow-water habitats, such as salt marshes and seagrass beds. Although the effects of habitat degradation on community structure within intertidal marshes have been well studied, little is known about the impact of habitat degradation on, and the ecological value of, subtidal shallow-water habitats, despite the prevalence of these habitats in coastal ecosystems. In coastal habitats, bivalves are dominant benthic organisms that can comprise over 50% of benthic prey biomass and are indicative of benthic production. We quantified bivalve diversity, density, and biomass in deep and shallow (< 1.5 m MLW) unstructured subtidal habitats in 2 tributaries of lower Chesapeake Bay (Elizabeth-Lafayette River system and York River). We also examined the effects of shoreline alteration in shallow habitats by contrasting the benthos of the subtidal areas adjacent to natural marsh, bulkhead, and rip-rap shorelines. Bivalve diversity, density, and biomass were significantly higher in shallow than in deep benthic habitats in both systems. Benthic abundance and diversity were higher in subtidal habitats adjacent to natural marsh than those adjacent to bulkhead shorelines; abundance and diversity were intermediate in rip-rap shorelines, and appeared to depend on landscape features. Predator density and diversity tended to be highest adjacent to natural marsh shorelines, and density of crabs was significantly higher in natural marsh than in bulkhead habitats. There is thus a crucial link between natural marshes, infaunal prey in subtidal habitats, and predator abundance. Consequently, the indirect effects of coastal habitat degradation upon secondary production in the shallow, subtidal habitats adjacent to salt marshes may be as great as or greater than direct habitat effects.


Mesocosm Study Of Particle Dynamics And Control Of Particle-Associated Bacteria By Flagellate Grazing, Kam W. Tang, Hans-Peter Grossart, Emily M. Yam, George A. Jackson Jan 2006

Mesocosm Study Of Particle Dynamics And Control Of Particle-Associated Bacteria By Flagellate Grazing, Kam W. Tang, Hans-Peter Grossart, Emily M. Yam, George A. Jackson

VIMS Articles

The goal of this study was to attain an integrated understanding of the dynamics of attached microbial communities in nature as governed by the component processes of particle formation, colonization, detachment, growth and interspecific interactions among the microbes. The study was conducted in mesocosms in a Danish fjord over a 2 wk period in April to May 2005. Despite nutrient additions, chlorophyll and particle concentrations were low and no distinct phytoplankton blooms were observed. Particle volume concentration was dominated by particles > 100 Pm. The abundance of attached bacteria was weakly but positively correlated with total particle volume. Phylogenetic composition of ...


Limits To Top-Down Control Of Phytoplankton By Oysters In Chesapeake Bay, Lawrence R. Pomeroy, Christopher F. D'Elia, Linda C. Schaffner Jan 2006

Limits To Top-Down Control Of Phytoplankton By Oysters In Chesapeake Bay, Lawrence R. Pomeroy, Christopher F. D'Elia, Linda C. Schaffner

VIMS Articles

Restoration of the oyster Crassostrea virginica population in Chesapeake Bay is often advocated as an easy solution for controlling phytoplankton blooms. Even at their pre-colonial densities, oysters are unlikely to have controlled blooms, despite the fact that sediment cores suggest that pre-colonial spring blooms were smaller than at present. Lack of access to all bay water and low springtime filtration rates would make it impossible for oysters to control the spring bloom and the resulting summer hypoxia. Previous studies have overestimated potential oyster filtration rates, because they extrapolated summer rates to spring conditions that are 20 degrees C cooler. Previous ...


Plankton Development And Trophic Transfer In Seawater Enclosures With Nutrients And Phaeocystis Pouchetii Added, J. C. Nejstgaard, M. E. Frischer, P. G. Verity, J. T. Anderson, A. Jacobson, Mj Zirbel, A. Larsen, J. Mrtinez-Martinez, Af. Sazhin, T. Walters, Da Bronk, Sj. Whipple, Sr. Borrett, Bc Patten, Jd Long Jan 2006

Plankton Development And Trophic Transfer In Seawater Enclosures With Nutrients And Phaeocystis Pouchetii Added, J. C. Nejstgaard, M. E. Frischer, P. G. Verity, J. T. Anderson, A. Jacobson, Mj Zirbel, A. Larsen, J. Mrtinez-Martinez, Af. Sazhin, T. Walters, Da Bronk, Sj. Whipple, Sr. Borrett, Bc Patten, Jd Long

VIMS Articles

In high latitude planktonic ecosystems where the prymnesiophyte alga Phaeocystis pouchetii is often the dominant primary producer, its importance in structuring planktonic food webs is well known. In this study we investigated how the base of the planktonic food web responds to a P. pouchetii colony bloom in controlled mesocosm systems with natural water enclosed in situ in a West Norwegian fjord. Similar large (11 m(3)) mesocosm studies were conducted in 2 successive years and the dynamics of various components of the planktonic food web from viruses to mesozooplankton investigated. In 2002 (4 to 24 March), 3 mesocosms comprising ...


Predation On Posidonia Australis Seeds In Seagrass Habitats Of Rottnest Island, Western Australia: Patterns And Predators, R J. Orth, Gary A. Kendrick, Scott R. Marion Jan 2006

Predation On Posidonia Australis Seeds In Seagrass Habitats Of Rottnest Island, Western Australia: Patterns And Predators, R J. Orth, Gary A. Kendrick, Scott R. Marion

VIMS Articles

Seed predation is an important process governing the dynamics of many plant populations. We assessed seed mortality due to predation in the seagrass Posidonia australis by identifying predators and quantifying predation events using underwater video cameras, laboratory and field observations, and field tethering experiments in shallow-water habitats off Rottnest Island, Western Australia in 2003 (2 sites) and 2004 (5 sites). We assessed 4 dominant habitats: within seagrass meadows of (1) P. australis, (2) Amphibolis antarctica and (3) Halophila ovalis, and on (4) unvegetated sand. Video analysis and field and laboratory observations showed that at least 6 different crustacean taxa were ...


Why Biodiversity Is Important To Oceanography: Potential Roles Of Genetic, Species, And Trophic Diversity In Pelagic Ecosystem Processes, J. Emmett Duffy, John J. Stachowicz Jan 2006

Why Biodiversity Is Important To Oceanography: Potential Roles Of Genetic, Species, And Trophic Diversity In Pelagic Ecosystem Processes, J. Emmett Duffy, John J. Stachowicz

VIMS Articles

The functioning of the global ecosystem is mediated in large part by pelagic marine organisms through their influence on biomass production, elemental cycling, and atmospheric composition. Growing theoretical and empirical evidence suggests that the stability and functioning of this complex system may depend, not only on aggregate biomass and production of pelagic producers and consumers, but also on the composition and richness of taxa within those compartments, Yet rigorous experimental tests of relationships between diversity and these aspects of pelagic ecosystem functioning are virtually unknown, Here, we argue for more attention to such research, and we marshal preliminary evidence that ...


Temporal And Vertical Dynamics In Picoplankton Photoheterotrophic Production In The Subtropical North Pacific Ocean, M. J. Church, H. W. Ducklow, Et Al Jan 2006

Temporal And Vertical Dynamics In Picoplankton Photoheterotrophic Production In The Subtropical North Pacific Ocean, M. J. Church, H. W. Ducklow, Et Al

VIMS Articles

Heterotrophic microbial production is a fundamental determinant in the flow of bioelements and energy within the pelagic ecosystems of the open ocean. To characterize the temporal dynamics in rates of heterotrophic picoplankton production (HPP), we examined vertical profiles of H-3-leucine (H-3-leu) and [methyl-H-3]-thymidine (H-3-TdR) incorporation at Stn ALOHA (22 degrees 45'N, 158 degrees W) in the oligotrophic North Pacific Ocean. Euphotic zone rates of H-3-leu and H-3-TdR incorporation were measured in situ under light and dark conditions on cruises to Stn ALOHA between April 2000 and August 2005. Rates of H-3-leu and H-3-TdR incorporation were elevated in the ...


Molecular Detection Of Hematodinium Spp. In Norway Lobster Nephrops Norvegicus And Other Crustaceans, Hamish J. Small, Dm Neil, Ac Taylor, Et Al Jan 2006

Molecular Detection Of Hematodinium Spp. In Norway Lobster Nephrops Norvegicus And Other Crustaceans, Hamish J. Small, Dm Neil, Ac Taylor, Et Al

VIMS Articles

The Norway lobster Nephrops norvegicus (L.) from the coastal waters of Scotland is seasonally infected by a parasitic dinoflagellate of the genus Hematodinium. Methods used to detect infection include a morphological index (pleopod diagnosis) and several immunoassays. The present study describes the development and application of a set of Hematodinium-specific polymerase chain reaction (PCR) primers and DNA probes based on Hematodinium ribosomal DNA (rDNA). In the PCR assay, a diagnostic band of 380 bp was consistently amplified from total genomic DNA isolated from Hematodinium-infected N. norvegicus. The sensitivity of the assay was 1 ng DNA, which is equivalent to 0 ...


Complications Of A Non-Native Oyster Introduction: Facilitation Of A Local Parasite, Melanie J. Bishop, Ryan Carnegie, Nancy A. Stokes, Charles H. Peterson, Eugene Burreson Jan 2006

Complications Of A Non-Native Oyster Introduction: Facilitation Of A Local Parasite, Melanie J. Bishop, Ryan Carnegie, Nancy A. Stokes, Charles H. Peterson, Eugene Burreson

VIMS Articles

Among the risks of introducing non-native species to novel environments is the possibility that the non-native might serve as a reservoir for enzootic pathogens formerly at low abundance. The recent identification of Bonamia sp. in previously uninfected non-native Suminoe oysters deployed to Bogue Sound, Morehead City, North Carolina, USA, raises serious concerns about the oyster's ability to act as a reservoir for the parasite, not formerly known along the east coast of the USA. To assess the current distribution of the Bonamia sp. parasite and its environmental tolerances, non-reproductive triploid Suminoe oysters, certified as uninfected, were deployed at 5 ...


Depth-Specific Differences In Growth Of The Reef Sponge Callyspongia Vaginalis: Role Of Bottom-Up Effects, Geoffrey C. Trussell, Michael P. Lesser, Mark R. Patterson, Salvatore J. Genovese Jan 2006

Depth-Specific Differences In Growth Of The Reef Sponge Callyspongia Vaginalis: Role Of Bottom-Up Effects, Geoffrey C. Trussell, Michael P. Lesser, Mark R. Patterson, Salvatore J. Genovese

VIMS Articles

Callyspongia vaginalis, a common reef sponge in the Florida Keys, USA, exhibits depth-specific differences in bioenergetics and growth that are a function of food availability. We measured several physiological parameters in situ to construct the bioenergetic budgets of sponges living in deep and shallow waters. Respiration rates were measured in a recirculating flow respirometer and pumping rates were measured by filming dye ejected from sponge oscula. In addition, inhalent and exhalent water sampled from around sponge colonies at both depths was analyzed using flow cytometry to quantify the concentration and clearance rates of picoplankton. These parameters were used to construct ...