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Full-Text Articles in Life Sciences
Overcoming Restoration Paradigms: Value Of The Historical Record And Metapopulation Dynamics In Native Oyster Restoration, Rom Lipcius, Russell P. Burke, Danielle N. Mcculloch, Sebastian J. Schreiber, David M. Schulte, Rochelle D. Seitz, Jian Shen
Overcoming Restoration Paradigms: Value Of The Historical Record And Metapopulation Dynamics In Native Oyster Restoration, Rom Lipcius, Russell P. Burke, Danielle N. Mcculloch, Sebastian J. Schreiber, David M. Schulte, Rochelle D. Seitz, Jian Shen
VIMS Articles
Restoration strategies for native oyster populations rely on multiple sources of information, which often conflict due to time- and space-varying patterns in abundance and distribution. For instance, strategies based on population connectivity and disease resistance can differ, and extant and historical records of abundance and distribution are often at odds, such that the optimal strategy is unclear and valuable restoration sites may be excluded from consideration. This was the case for the Lynnhaven River subestuary of lower Chesapeake Bay, which was deemed unsuitable for Eastern Oyster (Crassostrea virginica) restoration based on physical conditions, disease challenge, and extant oyster …
Trophic Cascades In The Western Ross Sea, Antarctica: Revisited, David G. Ainley, Grant Ballard, Randolph M. Jones, Dennis Jongsomjit, Stephen D. Pierce, Walker O. Smith Jr., Sam Veloz
Trophic Cascades In The Western Ross Sea, Antarctica: Revisited, David G. Ainley, Grant Ballard, Randolph M. Jones, Dennis Jongsomjit, Stephen D. Pierce, Walker O. Smith Jr., Sam Veloz
VIMS Articles
We investigated mesopredator effects on prey availability in the Ross Sea, Antarctica, as - sessing the reasons why Adélie penguin Pygoscelis adeliae foraging trip duration (FTD) increases and diet changes from krill to fish as numbers of foraging penguins and competing cetaceans increase in the penguins’ foraging area. To investigate penguins’ seasonally changing FTD as a function of foraging-population size—previously investigated indirectly—we used bio-logging to determine the penguins’ 3-dimensional foraging volume, while an autonomous glider quantified the depth, abundance, and distribution of potential prey. As numbers of foraging penguins and cetaceans increased, penguins spent more time on foraging trips, traveling …
Abstracts Of Technical Papers, Presented At The 107th Annual Meeting, National Shellfisheries Association, Monterey, California, March 22–26, 2015, National Shellfisheries Association
Abstracts Of Technical Papers, Presented At The 107th Annual Meeting, National Shellfisheries Association, Monterey, California, March 22–26, 2015, National Shellfisheries Association
VIMS Articles
No abstract provided.
Enhanced Nutrient Regeneration At Commercial Hard Clam (Mercenaria Mercenaria) Beds And The Role Of Macroalgae, Anna E. Murphy, Iris C. Anderson, Mark W. Luckenbach
Enhanced Nutrient Regeneration At Commercial Hard Clam (Mercenaria Mercenaria) Beds And The Role Of Macroalgae, Anna E. Murphy, Iris C. Anderson, Mark W. Luckenbach
VIMS Articles
High densities of bivalves found in aquaculture can exert ‘top-down’ control on primary production through feeding while simultaneously influencing local ‘bottom-up’ effects on production by enhancing nutrient recycling. Thus bivalves may decrease or increase localized eutrophication (sensu Nixon), depending on environmental conditions and specific culture practices. This study investigates hard clam aquaculture influence on benthic nutrient regeneration and metabolism, seasonally using in situ incubations. Effects of macroalgae, which proliferate on predator-exclusion nets at cultivation sites, are also investigated. Ammonium (NH4 +) and phosphate effluxes averaged 154 and 100 times higher, respectively, at clam beds compared to reference sediments. Macroalgae decreased …
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 …
Genetic And Biogeochemical Investigation Of Sedimentary Nitrogen Cycling Communities Responding To Tidal And Seasonal Dynamics In Cape Fear River Estuary, Ja Lisa, Bk Song, Cr Tobias, De Hines
Genetic And Biogeochemical Investigation Of Sedimentary Nitrogen Cycling Communities Responding To Tidal And Seasonal Dynamics In Cape Fear River Estuary, Ja Lisa, Bk Song, Cr Tobias, De Hines
VIMS Articles
Tidal and seasonal fluctuations in the oligohaline reaches of estuaries may alter geochemical features that influence structure and function of microbial communities involved in sedimentary nitrogen (N) cycling. In order to evaluate sediment community responses to short-term (tidal) and long-term (seasonal) changes in different tidal regimes, nitrogen cycling rates and genes were quantified in three sites that span a range of tidal influence in the upper portion of the Cape Fear River Estuary. Environmental parameters were monitored during low and high tides in winter and spring. N-15 tracer incubation experiments were conducted to measure nitrification, denitrification, anaerobic ammonium oxidation (anammox), …
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 …