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Full-Text Articles in Aquaculture and Fisheries
Dissolved Oxygen Dynamics During A Phytoplankton Bloom In The Ross Sea Polynya, By Queste, Kj Heywood, Walker O. Smith Jr., De Kaufman, Td Jickells, Ms Dinniman
Dissolved Oxygen Dynamics During A Phytoplankton Bloom In The Ross Sea Polynya, By Queste, Kj Heywood, Walker O. Smith Jr., De Kaufman, Td Jickells, Ms Dinniman
VIMS Articles
The Ross Sea polynya is one of the most productive regions in the Southern Ocean. However, limited access and high spatio-temporal variability of physical and biological processes limit the use of conventional oceanographic methods to measure early season primary productivity. High-resolution observations from two Seagliders provide insights into the timing of a bloom in the southern Ross Sea polynya in December 2010. Changes in chlorophyll and oxygen concentrations are used to assess bloom dynamics. Using a ratio of dissolved oxygen to carbon, net primary production is estimated over the duration of the bloom showing a sensitive balance between net autotrophy …
Vertical Mixing, Critical Depths, And Phytoplankton Growth In The Ross Sea, Walker O. Smith Jr., Rm Jones
Vertical Mixing, Critical Depths, And Phytoplankton Growth In The Ross Sea, Walker O. Smith Jr., Rm Jones
VIMS Articles
Phytoplankton growth and biomass accumulation vary spatially and temporally in the Ross Sea, largely as a function of ice concentrations, vertical mixing depths, and iron concentrations. To assess the role of vertical mixing in bloom initiation, we used a high-resolution numerical model to estimate changes in mixed layer depths from October 1 through early December, the period where phytoplankton growth begins and biomass accumulates, and estimate critical depths for this period. Mixed layers in October ranged from the complete water column (>600 m) to ca. 200 m; over a 60-day period, the mixed layers decreased on average by 70%. …
Projected Impacts Of Climate Warming On The Functional And Phylogenetic Components Of Coastal Mediterranean Fish Biodiversity, C Albouy, F Leprieur, F Le Loc'h, N Mouquet, Cn Meynard, Et Al.
Projected Impacts Of Climate Warming On The Functional And Phylogenetic Components Of Coastal Mediterranean Fish Biodiversity, C Albouy, F Leprieur, F Le Loc'h, N Mouquet, Cn Meynard, Et Al.
VIMS Articles
Climate warming affects biodiversity distribution across all ecosystems. However, beyond changes in species richness, impacts on other biodiversity components are still overlooked, particularly in the marine realm. Here we forecasted the potential effect of climate warming on the phylogenetic and functional components of coastal Mediterranean fish biodiversity. To do so, we used species distribution models to project the potential distribution of 230 coastal fish species by the end of the 21st century based on the IPCC A2 scenario implemented with the Mediterranean climatic model NEMOMED8. From these projections, we assessed the changes in phylogenetic (PD) and functional diversity (FD) of …
Detection And Diversity Of Copper Containing Nitrite Reductase Genes (Nirk) In Prokaryotic And Fungal Communities Of Agricultural Soils, A Long, Bk Song, K Fridey, A Silva
Detection And Diversity Of Copper Containing Nitrite Reductase Genes (Nirk) In Prokaryotic And Fungal Communities Of Agricultural Soils, A Long, Bk Song, K Fridey, A Silva
VIMS Articles
Microorganisms are capable of producing N-2 and N2O gases as the end products of denitrification. Copper-containing nitrite reductase (NirK), a key enzyme in the microbial N-cycle, has been found in bacteria, archaea and fungi. This study seeks to assess the diversity of nirK genes in the prokaryotic and fungal communities of agricultural soils in the United States. New primers targeting the nirK genes in fungi were developed, while nirK genes in archaea and bacteria were detected using previously published methods. The new primers were able to detect fungal nirK genes as well as bacterial nirK genes from a group that …
Biodiversity Mediates Top-Down Control In Eelgrass Ecosystems: A Global Comparative-Experimental Approach, Je Duffy, Pl Reynolds, C Bostrom, Ja Coyer, M Cusson, Et Al.
Biodiversity Mediates Top-Down Control In Eelgrass Ecosystems: A Global Comparative-Experimental Approach, Je Duffy, Pl Reynolds, C Bostrom, Ja Coyer, M Cusson, Et Al.
VIMS Articles
Nutrient pollution and reduced grazing each can stimulate algal blooms as shown by numerous experiments. But because experiments rarely incorporate natural variation in environmental factors and biodiversity, conditions determining the relative strength of bottom-up and top-down forcing remain unresolved. We factorially added nutrients and reduced grazing at 15 sites across the range of the marine foundation species eelgrass (Zostera marina) to quantify how top-down and bottom-up control interact with natural gradients in biodiversity and environmental forcing. Experiments confirmed modest top-down control of algae, whereas fertilisation had no general effect. Unexpectedly, grazer and algal biomass were better predicted by cross-site variation …
Mapping Diversity Indices: Not A Trivial Issue, V Granger, N Bez, Jm Fromentin, C Meynard, A Jadaud
Mapping Diversity Indices: Not A Trivial Issue, V Granger, N Bez, Jm Fromentin, C Meynard, A Jadaud
VIMS Articles
Mapping diversity indices, that is estimating values in all locations of a given area from some sampled locations, is central to numerous research and applied fields in ecology. Two approaches are used to map diversity indices without including abiotic or biotic variables: (i) the indirect approach, which consists in estimating each individual species distribution over the area, then stacking the distributions of all species to estimate and map a posteriori the diversity index, (ii) the direct approach, which relies on computing a diversity index in each sampled locations and then to interpolate these values to all locations of the studied …
Properties Of Age Compositions And Mortality Estimates Derived From Cohort Slicing Of Length Data, Le Ailloud, Mw Smith, Ay Then, Kl Omori, Gm Ralph, Jm Hoenig
Properties Of Age Compositions And Mortality Estimates Derived From Cohort Slicing Of Length Data, Le Ailloud, Mw Smith, Ay Then, Kl Omori, Gm Ralph, Jm Hoenig
VIMS Articles
Cohort slicing can be used to obtain catch-at-age data from length frequency distributions when directly measured age data are unavailable. The procedure systematically underestimates the relative abundance of the youngest age groups and overestimates abundance at older ages. Cohort-sliced catch-at-age data can be used to estimate total mortality rate (Z) using a regression estimator or the Chapman-Robson estimator for right truncated data. However, the effect of cohort slicing on accuracy and precision of resulting Z estimates remains to be determined. We used Monte Carlo simulation to estimate the per cent bias and per cent root mean square error of the …
Copepod Carcasses As Microbial Hot Spots For Pelagic Denitrification, Rn Glud, Hp Grossart, M Larsen, Kw Tang, Ke Arendt, Et Al
Copepod Carcasses As Microbial Hot Spots For Pelagic Denitrification, Rn Glud, Hp Grossart, M Larsen, Kw Tang, Ke Arendt, Et Al
VIMS Articles
Copepods are exposed to a high non-predatory mortality and their decomposing carcasses act as microniches with intensified microbial activity. Sinking carcasses could thereby represent anoxic microenvironment sustaining anaerobic microbial pathways in otherwise oxic water columns. Using non-invasive O-2 imaging, we document that carcasses of Calanus finmarchicus had an anoxic interior even at fully air-saturated ambient O-2 level. The extent of anoxia gradually expanded with decreasing ambient O-2 levels. Concurrent microbial sampling showed the expression of nitrite reductase genes (nirS) in all investigated carcass samples and thereby documented the potential for microbial denitrification in carcasses. The nirS gene was occasionally expressed …
Influence Of Central Pacific Oceanographic Conditions On The Potential Vertical Habitat Of Four Tropical Tuna Species, Al Deary, S Moret-Ferguson, M Engels, E Zettler, G Jaroslow
Influence Of Central Pacific Oceanographic Conditions On The Potential Vertical Habitat Of Four Tropical Tuna Species, Al Deary, S Moret-Ferguson, M Engels, E Zettler, G Jaroslow
VIMS Articles
Climate change has resulted in the geographic and vertical expansion of oxygen minimum zones but their impact on the vertical distribution of commercially important species, such as tunas, is not well understood. Although La Nina events are characterized by increased upwelling along the equator, the increased primary productivity and bacterial proliferation drive the expansion of oxygen minimum zones. Vertical habitat of four tropical tuna species were characterized using direct observations of the oceanographic conditions of the Central Pacific Ocean during the 2008 La Nina event and existing primary literature on temperature and dissolved oxygen physiological tolerances for these tunas. Concentrations …
Corrigendum To Visual Acuity In Pelagic Fishes And Mollusks (Vol 92, Pg 1, 2013), Yl Gagnon, Tt Sutton, S Johnsen
Corrigendum To Visual Acuity In Pelagic Fishes And Mollusks (Vol 92, Pg 1, 2013), Yl Gagnon, Tt Sutton, S Johnsen
VIMS Articles
No abstract provided.
Reproductive Skew Drives Patterns Of Sexual Dimorphism In Sponge-Dwelling Snapping Shrimps, Stc Chak, Je Duffy, Dr Rubenstein
Reproductive Skew Drives Patterns Of Sexual Dimorphism In Sponge-Dwelling Snapping Shrimps, Stc Chak, Je Duffy, Dr Rubenstein
VIMS Articles
Sexual dimorphism is typically a result of strong sexual selection on male traits used in male male competition and subsequent female choice. However, in social species where reproduction is monopolized by one or a few individuals in a group, selection on secondary sexual characteristics may be strong in both sexes. Indeed, sexual dimorphism is reduced in many cooperatively breeding vertebrates and eusocial insects with totipotent workers, presumably because of increased selection on female traits. Here, we examined the relationship between sexual dimorphism and sociality in eight species of Synalpheus snapping shrimps that vary in social structure and degree of reproductive …
Marine Biodiversity And Ecosystem Functioning: What's Known And What's Next?, L Gamfeldt, Js Lefcheck, Jek Byrnes, Bj Cardinale, Je Duffy
Marine Biodiversity And Ecosystem Functioning: What's Known And What's Next?, L Gamfeldt, Js Lefcheck, Jek Byrnes, Bj Cardinale, Je Duffy
VIMS Articles
Marine ecosystems are experiencing rapid and pervasive changes in biodiversity and species composition. Understanding the ecosystem consequences of these changes is critical to effectively managing these systems. Over the last several years, numerous experimental manipulations of species richness have been performed, yet existing quantitative syntheses have focused on a just a subset of processes measured in experiments and, as such, have not summarized the full data available from marine systems. Here, we present the results of a meta-analysis of 110 marine experiments from 42 studies that manipulated the species richness of organisms across a range of taxa and trophic levels …
Biogeochemical Variability In The Southern Ross Sea As Observed By A Glider Deployment, De Kaufman, Mam Friedrichs, Wj Smith Jr., By Queste, Kj Heywood
Biogeochemical Variability In The Southern Ross Sea As Observed By A Glider Deployment, De Kaufman, Mam Friedrichs, Wj Smith Jr., By Queste, Kj Heywood
VIMS Articles
High-resolution autonomous glider data (including temperature, salinity, fluorescence, and optical backscatter) collected during the 2010-2011 austral summer identified variations in phytoplankton biomass along two glider sections near 76 degrees 40'S. Sea surface temperatures were warmer during the latter, westward section, while mixed layer depths were deeper. Substantial quantities of Modified Circumpolar Deep Water, identified by neutral density criteria, were located within both sections. Chlorophyll (Chl) concentrations computed from fluorescence exhibited daily quenching near the surface, and deep chlorophyll concentrations at 200 m became periodically elevated, suggesting substantial export on small space and time scales. The concentrations of particulate organic carbon …
Field Experimental Evidence That Grazers Mediate Transition Between Microalgal And Seagrass Dominance, Pl Reynolds, Jp Richardson, Je Duffy
Field Experimental Evidence That Grazers Mediate Transition Between Microalgal And Seagrass Dominance, Pl Reynolds, Jp Richardson, Je Duffy
VIMS Articles
We tested the relative effects of nutrient loading, reduced predation, and reduced grazing on eelgrass community dynamics in Chesapeake Bay and found evidence supporting the "mutualistic mesograzer model" in which small invertebrate grazers control accumulation of epiphytic algae, buffer eutrophication effects, and thus facilitate seagrass dominance. Experimental reduction of crustacean grazers in the field stimulated a nearly sixfold increase in epiphytic algae, and reduced seagrass biomass by 65% compared to controls with grazers. Nutrient fertilization generally had much weaker effects, but an interaction with mesograzers was key in changing the sign of fertilization effects on the system: aboveground eelgrass biomass …
Individual, Population, And Ecosystem Effects Of Hypoxia On A Dominant Benthic Bivalve In Chesapeake Bay, W. Christopher Long, Rochelle D. Seitz, Bryce J. Brylawski, Romuald N. Lipcius
Individual, Population, And Ecosystem Effects Of Hypoxia On A Dominant Benthic Bivalve In Chesapeake Bay, W. Christopher Long, Rochelle D. Seitz, Bryce J. Brylawski, Romuald N. Lipcius
VIMS Articles
Hypoxia is an environmental stressor that affects abundance, biomass,diversity, and ecosystem function of benthic assemblages worldwide, yet its collective impact at individual, population, and ecosystem levels has rarely been investigated. We examined the effects of hypoxia on the biomass-dominant clam,Macoma balthica, in the York and Rappahannock Rivers (Chesapeake Bay, USA). We (1) surveyed the M. balthica populationsin both rivers in 2003 and 2004, (2) determined the effects of low dissolved oxygen (DO) on M.balthica fecundity in a laboratory experiment, and (3) employed a predator-exclusion fieldexperiment to establish the effects of hypoxia and prey density on predation upon M. balthica.The resultant …
Multifunctionality Does Not Imply That All Functions Are Positively Correlated, J Byrnes, Js Lefcheck, L Gamfeldt, Jn Griffin, F Isbell
Multifunctionality Does Not Imply That All Functions Are Positively Correlated, J Byrnes, Js Lefcheck, L Gamfeldt, Jn Griffin, F Isbell
VIMS Articles
No abstract provided.
Value Of Coastal Habitats For Exploited Species: Introduction To A Theme Set Of Articles, Rochelle D. Seitz
Value Of Coastal Habitats For Exploited Species: Introduction To A Theme Set Of Articles, Rochelle D. Seitz
VIMS Articles
Many exploited fish and invertebrate species use coastal habitats during one or more life-history stages as spawning, feeding, and nursery areas; yet, the value of these habitats has not been adequately characterized. As habitat availability can be a bottleneck for many populations, concerns about habitat effects on exploited species have been increasing. We have compiled nine articles presenting the state of knowledge and future research priorities regarding the importance of habitat for exploited species. Reviews from European habitats and several geographical locations throughout the United States demonstrate the influence of coastal habitats on survival, growth, and movement, especially during the …
Zooplankton Carcasses And Non-Predatory Mortality In Freshwater And Inland Sea Environments, Kw Tang, Mi Gladyshev, Op Dubovskaya, G Kirillin, Hp Grossart
Zooplankton Carcasses And Non-Predatory Mortality In Freshwater And Inland Sea Environments, Kw Tang, Mi Gladyshev, Op Dubovskaya, G Kirillin, Hp Grossart
VIMS Articles
Zooplankton carcasses are ubiquitous in marine and freshwater systems, implicating the importance of non-predatory mortality, but both are often overlooked in ecological studies compared with predatory mortality. The development of several microscopic methods allows the distinction between live and dead zooplankton in field samples, and the reported percentages of dead zooplankton average 11.6 (minimum) to 59.8 (maximum) in marine environments, and 7.4 (minimum) to 47.6 (maximum) in fresh and inland waters. Common causes of non-predatory mortality among zooplankton include senescence, temperature change, physical and chemical stresses, parasitism and food-related factors. Carcasses resulting from non-predatory mortality may undergo decomposition leading to …
Ecological Value Of Coastal Habitats For Commercially And Ecologically Important Species, Rochelle D. Seitz, H Wennhage, U Bergstrom, Rn Lipcius, T Ysebaert
Ecological Value Of Coastal Habitats For Commercially And Ecologically Important Species, Rochelle D. Seitz, H Wennhage, U Bergstrom, Rn Lipcius, T Ysebaert
VIMS Articles
Many exploited fish and macroinvertebrates that utilize the coastal zone have declined, and the causes of these declines, apart from overfishing, remain largely unresolved. Degradation of essential habitats has resulted in habitats that are no longer adequate to fulfil nursery, feeding, or reproductive functions, yet the degree to which coastal habitats are important for exploited species has not been quantified. Thus, we reviewed and synthesized literature on the ecological value of coastal habitats (i.e. seagrass beds, shallow subtidal and intertidal habitats, kelp beds, shallow open water habitats, saltmarshes, mussel beds, macroalgal beds, rocky bottom, and mariculture beds) as feeding grounds, …
Paradox Reconsidered: Methane Oversaturation In Well-Oxygenated Lake Waters, Kw Tang, Df Mcginnis, K Frindte, V Bruchert, Hp Grossart
Paradox Reconsidered: Methane Oversaturation In Well-Oxygenated Lake Waters, Kw Tang, Df Mcginnis, K Frindte, V Bruchert, Hp Grossart
VIMS Articles
The widely reported paradox of methane oversaturation in oxygenated water challenges the prevailing paradigm that microbial methanogenesis only occurs under anoxic conditions. Using a combination of field sampling, incubation experiments, and modeling, we show that the recurring mid-water methane peak in Lake Stechlin, northeast Germany, was not dependent on methane input from the littoral zone or bottom sediment or on the presence of known micro-anoxic zones. The methane peak repeatedly overlapped with oxygen oversaturation in the seasonal thermocline. Incubation experiments and isotope analysis indicated active methane production, which was likely linked to photosynthesis and/or nitrogen fixation within the oxygenated water, …
Biodiversity In A Changing Climate: A Synthesis Of Current And Projected Trends In The Us, Md Staudinger, Sl Carter, Ms Cross, Ns Dubois, Je Duffy, Et Al.
Biodiversity In A Changing Climate: A Synthesis Of Current And Projected Trends In The Us, Md Staudinger, Sl Carter, Ms Cross, Ns Dubois, Je Duffy, Et Al.
VIMS Articles
This paper provides a synthesis of the recent literature describing how global biodiversity is being affected by climate change and is projected to respond in the future. Current studies reinforce earlier findings of major climate-change-related impacts on biological systems and document new, more subtle after-effects. For example, many species are shifting their distributions and phenologies at faster rates than were recorded just a few years ago; however, responses are not uniform across species. Shifts have been idiosyncratic and in some cases counterintuitive, promoting new community compositions and altering biotic interactions. Although genetic diversity enhances species' potential to respond to variable …
Oyster-Mediated Benthic-Pelagic Coupling Modifies Nitrogen Pools And Processes, Ar Smyth, Nr Geraldi, Mf Piehler
Oyster-Mediated Benthic-Pelagic Coupling Modifies Nitrogen Pools And Processes, Ar Smyth, Nr Geraldi, Mf Piehler
VIMS Articles
Removal of nitrogen through enhanced denitrification has been identified as an ecosystem service provided by oysters. In this study, we assessed the effects of an individual oyster (Crassostrea virginica) on nitrogen dynamics. Fluxes of N-2, O-2, nitrate/nitrite (NOx) and ammonium (NH4+) were measured from continuous-flow microcosms that contained a live oyster, sediment, or a live oyster + sediment. Net N-2 fluxes were indicative of nitrogen fixation in the sediment treatment and denitrification in the oyster and oyster + sediment treatments. Organic matter de position and ammonium production associated with oyster biodeposits and excretion likely decreased N limitation, and …
Microzooplankton Grazing Along The Western Antarctic Peninsula, Lm Garzio, Deborah K. Steinberg, M Erickson, Hw Ducklow
Microzooplankton Grazing Along The Western Antarctic Peninsula, Lm Garzio, Deborah K. Steinberg, M Erickson, Hw Ducklow
VIMS Articles
The significance of microzooplankton as grazers in pelagic ecosystems has been established, yet relatively few studies of microzooplankton grazing, compared to that of macrozooplankton, have been conducted in the Southern Ocean. We report phytoplankton and bacterial growth and grazing mortality rates along the Western Antarctic Peninsula (WAP), a region of rapid climate change. Growth and grazing rates were determined by dilution experiments at select stations along the WAP in January of 2009 to 2011 and in the nearshore waters near Palmer Station in February and March 2011. Microzooplankton exerted higher grazing pressure on bacteria compared to phytoplankton along the WAP …
Broad-Scale Association Between Seagrass Cover And Juvenile Blue Crab Density In Chesapeake Bay, Gina M. Ralph, Rochelle D. Seitz, R J. Orth, Kathleen E. Knick, Rom Lipcius
Broad-Scale Association Between Seagrass Cover And Juvenile Blue Crab Density In Chesapeake Bay, Gina M. Ralph, Rochelle D. Seitz, R J. Orth, Kathleen E. Knick, Rom Lipcius
VIMS Articles
Although numerous small-scale laboratory, mesocosm, and field experiments have demonstrated that abundance, survival, and growth of juvenile fish and invertebrates are higher in vegetated than in unvegetated habitats, the effect of habitat quality (i.e. habitat complexity) within vegetated habitats has not been documented at a broad spatial scale. We examined the relationship between percent cover in seagrass beds (eelgrass Zostera marina, widgeon grass Ruppia maritima, and associated macroalgae) and juvenile blue crab Callinectes sapidus density at a broad spatial scale. We quantified the functional relationship between juvenile density and percent cover of vegetation by sampling in Chesapeake Bay (USA) seagrass …
Carbon Fluxes And Pelagic Ecosystem Dynamics Near Two Western Antarctic Peninsula Adélie Penguin Colonies: An Inverse Model Approach, Sevrine F. Sailley, Hugh W. Ducklow, Holly V. Moeller, William R. Fraser, Oscar M. Schofield, Deborah K. Steinberg, Lori M. Garzio, Scott C. Doney
Carbon Fluxes And Pelagic Ecosystem Dynamics Near Two Western Antarctic Peninsula Adélie Penguin Colonies: An Inverse Model Approach, Sevrine F. Sailley, Hugh W. Ducklow, Holly V. Moeller, William R. Fraser, Oscar M. Schofield, Deborah K. Steinberg, Lori M. Garzio, Scott C. Doney
VIMS Articles
An inverse food-web model for the western Antarctic Peninsula (WAP) pelagic food web was constrained with data from Palmer Long Term Ecological Research (PAL-LTER) project annual austral summer sampling cruises. Model solutions were generated for 2 regions with Adélie penguin Pygoscelis adeliae colonies presenting different population trends (a northern and a southern colony) for a 12 yr period (1995−2006). Counter to the standard paradigm, comparisons of carbon flow through bacteria, microzooplankton, and krill showed that the diatom−krill−top predator food chain is not the dominant pathway for organic carbon exchanges. The food web is more complex, including significant contributions by microzooplankton …
The Importance Of Dissimilatory Nitrate Reduction To Ammonium (Dnra) In The Nitrogen Cycle Of Coastal Ecosystems, Ae Giblin, Cr Tobias, Bk Song, N Weston, Gt Banta
The Importance Of Dissimilatory Nitrate Reduction To Ammonium (Dnra) In The Nitrogen Cycle Of Coastal Ecosystems, Ae Giblin, Cr Tobias, Bk Song, N Weston, Gt Banta
VIMS Articles
Until recently, it was believed that biological assimilation and gaseous nitrogen (N) loss through denitrification were the two major fates of nitrate entering or produced within most coastal ecosystems. Denitrification is often viewed as an important ecosystem service that removes reactive N from the ecosystem. However, there is a competing nitrate reduction process, dissimilatory nitrate reduction to ammonium (DNRA), that conserves N within the ecosystem. The recent application of nitrogen stable isotopes as tracers has generated growing evidence that DNRA is a major nitrogen pathway that cannot be ignored. Measurements comparing the importance of denitrification vs. DNRA in 55 coastal …
Revision Of The Genus Centrophorus (Squaliformes: Centrophoridae): Part 1-Redescription Of Centrophorus Granulosus (Bloch & Schneider), A Senior Synonym Of C-Acus Garman And C-Niaukang Teng, Wt White, Da Ebert, Gjp Naylor, Hc Ho, P Clerkin, A Verissimo, Cf Cotton
Revision Of The Genus Centrophorus (Squaliformes: Centrophoridae): Part 1-Redescription Of Centrophorus Granulosus (Bloch & Schneider), A Senior Synonym Of C-Acus Garman And C-Niaukang Teng, Wt White, Da Ebert, Gjp Naylor, Hc Ho, P Clerkin, A Verissimo, Cf Cotton
VIMS Articles
The genus Centrophorus is one of the most taxonomically complex and confusing elasmobranch groups. A revision of this group is currently underway and this first paper sets an important foundation in this process by redescribing the type species of the genus-Centrophorus granulosus. This taxon name has been previously applied to two different morphotypes: a large species > 1.5 m TL and a smaller species similar to 1 m TL. Centrophorus acus and C. niaukang are the most commonly used names applied to the larger morphotype. The original description of C. granulosus was based on a large specimen of similar to 1.5 …
Penguin Biogeography Along The West Antarctic Peninsula Testing The Canyon Hypothesis With Palmer Lter Observations, O Schofield, H Ducklow, K Bernard, S Doney, D Patterson-Fraser, Et Al.
Penguin Biogeography Along The West Antarctic Peninsula Testing The Canyon Hypothesis With Palmer Lter Observations, O Schofield, H Ducklow, K Bernard, S Doney, D Patterson-Fraser, Et Al.
VIMS Articles
No abstract provided.
Contribution Of Sea Ice In The Southern Ocean To The Cycling Of Volatile Halogenated Organic Compounds, A Granfors, A Karlsson, E Mattsson, Walker O. Smith Jr., K Abrahamsson
Contribution Of Sea Ice In The Southern Ocean To The Cycling Of Volatile Halogenated Organic Compounds, A Granfors, A Karlsson, E Mattsson, Walker O. Smith Jr., K Abrahamsson
VIMS Articles
The contribution of sea ice to the flux of biogenic volatile halogenated organic compounds to the atmosphere in the Southern Ocean is currently not known. To approach this question, we measured halocarbons in sea ice, sea ice brine, and surface water of the Amundsen and Ross Seas. Concentrations in sea ice of these compounds, normalized to seawater salinity, ranged from 0.2 to 810 pmol L-1. Salinity-normalized chlorophyll a concentrations in the ice ranged from 3.5 to 190 mu gL(-1). Our results suggest biological production of halocarbons in sea ice, with maxima of halogenated organics and chlorophyll a commonly found in …
Krill Biomass And Aggregation Structure In Relation To Tidal Cycle In A Penguin Foraging Region Off The Western Antarctic Peninsula, Ks Bernard, Deborah K. Steinberg
Krill Biomass And Aggregation Structure In Relation To Tidal Cycle In A Penguin Foraging Region Off The Western Antarctic Peninsula, Ks Bernard, Deborah K. Steinberg
VIMS Articles
Antarctic krill are a key component of the diet of Adlie penguins inhabiting the Western Antarctic Peninsula (WAP), yet our understanding of the variability of krill distribution patterns within nearshore penguin feeding grounds is limited. A recent study of the foraging patterns of penguins breeding in the northern WAP suggests that tidal phase plays a role in foraging distance. We used acoustics to examine biomass and aggregation structure of krill in the penguin foraging grounds off Palmer Station during diurnal and semi-diurnal tides. Nearshore, integrated krill biomass during diurnal tides was significantly higher than during semi-diurnal tides. Krill aggregations were …