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Contaminant Levels in Fish Tissue from San Francisco Bay. Final Report.
Contaminant Levels in Fish Tissue from San Francisco Bay. Final Report.
San Francisco Regional Water Quality Control Board; California State Water Resources Control Board; California Department of Fish and Game, Marine Pollution Studies Laboratory. 149 pp.
Contaminant concentrations in sport fish from San Francisco Bay, 1997
Contaminant concentrations in sport fish from San Francisco Bay, 1997
In 1997, seven sport fish species were sampled from seven popular fishing areas in San Francisco Bay. Mercury exceeded a human health screening value in 44 of 84 (52%) samples. All collected samples of leopard shark and striped bass exceeded the mercury screening value of 0.23 μg/g wet weight. PCBs exceeded the screening value in 51 of 72 (71%) samples. DDT, chlordane, and dieldrin, had lower numbers of samples above screening values: 16 of 72 (22%) for DDT, 11 of 72 (15%) for chlordanes, and 27 of 72 (37%) for dieldrin. Concentrations of PCBs and other trace organics were highest in white croaker and shiner surfperch, the two species with the highest fat content in their muscle tissue. Fish from one location, Oakland Harbor, had significantly elevated wet weight concentrations of mercury, PCBs, DDTs, and chlordanes compared to other locations. Removal of skin from white croaker fillets reduced lipid concentrations by 27-49% and concentrations of trace organics by 33-40%. © 2002 Elsevier Science Ltd. All rights reserved., Cited By (since 1996):33 Fish and Fisheries, CODEN: MPNBA
Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California
Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California
An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia. Copyright© Taylor & Francis Inc., Cited By (since 1996):22 Marine Mammals, Birds & Turtles, CODEN: JTEHD
Contamination of biological samples by ingested sediment
Contamination of biological samples by ingested sediment
Cited By (since 1996):8, CODEN: MPNBA, An inorganic residue, presumed to be ingested sediment, was found in the rocky intertidal gastropods Tegula funebralis and Acmaea scabra and the estuarcopepods Acartia tonsa and A. clausi. When expressed as a percentage of the sample weight, this residue fraction often correlated significantly with the elemental concentrations measured in the organisms.
Contamination of the deep-sea
Contamination of the deep-sea
Cited By (since 1996):17 Oceanography, CODEN: MPNBA
Continental-shelf sediment as a primary source of iron for coastal phytoplankton
Continental-shelf sediment as a primary source of iron for coastal phytoplankton
The availability of iron, an essential nutrient, controls rates of phytoplankton primary productivity in the open-ocean, upwelling ecosystems of the equatorial Pacific. Upwelling injects large amounts of macronutrients into the euphotic zone of eastern boundary currents, such as the California Current System (CCS), where iron can become the limiting factor on productivity. Iron addition to samples from some areas of the CCS has been shown to increase rates of biomass production, but the processes that control iron availability in these systems remain poorly understood. Here we report measurements of dissolvable iron (that is, dissolved plus leachable iron at pH 3) in transects across the CCS in March of 1997 and 1998. We found high concentrations of iron in 1997 during strong upwelling conditions. During the 1998 El Nino, the concentration of dissolvable iron in surface waters was low, even though that year was marked by high river flow and low offshore salinity. These results indicate that the primary source of iron in the CCS is resuspension of particles in the benthic boundary layer, followed by upwelling of this iron-rich water, rather than direct riverine input. This source of iron must be an essential but variable component of the high productivity found in upwelling ecosystems., Cited By (since 1996):172 Oceanography, CODEN: NATUA
Continuous determination of nitrate concentrations in situ
Continuous determination of nitrate concentrations in situ
A submersible chemical analyser (Scanner) was used to measure nitrate concentrations in situ to depths of nearly 2000 m. Nitrate anomalies with a vertical span of 5 m can be detected at lowering rates up to 40 m min-1. The nitrate concentrations measured in situ are in good agreement with hydrographic data collected by conventional means at the same location. The relative standard deviation of the analyses performed in situ is ±0.79%. The method can be easily extended to most other colorimetric analyses., Cited By (since 1996):9 Oceanography
Control of community growth and export production by upwelled iron in the equatorial Pacific Ocean
Control of community growth and export production by upwelled iron in the equatorial Pacific Ocean
The iron hypothesis states that phytoplankton growth and biomass are limited by low concentrations of available iron in large regions of the world's oceans where other plant nutrients are abundant. Such limitation has been demonstrated by experiments in which iron has been added to both enclosed and in situ (un-enclosed) phytoplankton populations. A corollary of the iron hypothesis is that most 'new' iron is supplied by atmospheric deposition, and it has been suggested that changes in the deposition rates of iron-bearing dust have led to changes in biological productivity and, consequently, global climate. Here we report surface-water measurements in the equatorial Pacific Ocean which show that the main iron source to equatorial waters at 140°W is from upwelling waters. Shipboard in vitro experiments indicate that sub-nanomolar increases in iron concentrations can cause substantial increases in carbon export to deeper waters in this region. These findings demonstrate that equatorial biological production is controlled not solely by atmospheric iron deposition, but also by processes which influence the rate of upwelling and the iron concentration in upwelled water., Cited By (since 1996):221 Seaweeds, CODEN: NATUA
Cool seafloor hydrothermal springs reveal global geochemical fluxes
Cool seafloor hydrothermal springs reveal global geochemical fluxes
Article, We present geochemical data from the first samples of spring fluids from Dorado Outcrop, a basaltic edifice on 23 M.y. old seafloor of the Cocos Plate, eastern Pacific Ocean. These samples were collected from the discharge of a cool hydrothermal system (CHS) on a ridge flank, where typical reaction temperatures in the volcanic crust are low (2–20 °C) and fluid residence times are short. Ridge-flank hydrothermal systems extract 25% of Earth's lithospheric heat, with a global discharge rate equivalent to that of Earth's river discharge to the ocean; CHSs comprise a significant fraction of this global flow. Upper crustal temperatures around Dorado Outcrop are ∼15 °C, the calculated residence time is <3 y, and the composition of discharging fluids is only slightly altered from bottom seawater. Many of the major ions concentrations in spring fluids are indistinguishable from those of bottom seawater; however, concentrations of Rb, Mo, V, U, Mg, phosphate, Si and Li are different. Applying these observed differences to calculated global CHS fluxes results in chemical fluxes for these ions that are ≥15% of riverine fluxes. Fluxes of K and B also may be significant, but better analytical resolution is required to confirm this result. Spring fluids also have ∼50% less dissolved oxygen (DO) than bottom seawater. Calculations of an analytical model suggest that the loss of DO occurs primarily (>80%) within the upper basaltic crust by biotic and/or abiotic consumption. This calculation demonstrates that permeable pathways within the upper crust can support oxic water–rock interactions for millions of years.
Copper complexation in the Northeast Pacific
Copper complexation in the Northeast Pacific
Copper titrations were conducted at sea with differential pulse anodic stripping voltammetry to examine the degree to which copper was associated with organic ligands. Greater than 99.7% of the total dissolved copper in surface waters of the central Northeast Pacific shallower than 200 m was estimated to be associated with strong organic complexes. Below 200 m, increasing proportions of inorganic or labile copper species were observed. At middepths (1000 m), about 50-70% of the total dissolved copper was in the organically complexed form. Whereas total copper varies by a factor of only three from the surface to middepths (0.6-1.8 nM), copper complexation gives rise to extremely low cupric ion activities in surface waters ({Cu2+} = 1.4 × 10-4 M) and higher values at middepth ({Cu2+} = 10-11 M) -a variation of three orders of magnitude., Cited By (since 1996):208 Oceanography
Copper, zinc, cadmium and lead in surface waters of lakes Erie and Ontario
Copper, zinc, cadmium and lead in surface waters of lakes Erie and Ontario
Concentrations of Cu, Zn, Cd and Pb were determined from 16 stations in Lake Ontario and Lake Erie, using trace metal sampling and analytical technique developed for seawater analysis employing graphite furnace atomic absorption. While Cu concentrations are consistent with previously reported data for the Great Lakes, concentrations of Zn, Cd and Pb are one to two orders of magnitude below those previously reported. These new data, however, were substantiated by complementary measurements of these samples for Pb concentrations and isotopic compositions as determined by isotope dilution mass spectrometry in a concurrent study, and are consistent with measurements of these elements in oceanic surface waters. Using reported trace metal inputs, these current measurements yield estimates for the residence times of Cu, Zn, Cd and Pb in the Lake Ontario epilimnion of 950, 5, 9, and 4 days, respectively. Lake Erie residence times are similar, averaging 660, 23, 20 and 9 days for Cu, Zn, Cd and Pb respectively. These short residence times are qualified by the imprecision of the elemental input estimates., Cited By (since 1996):30, CODEN: STEVA
Coralline algal rhodoliths enhance larval settlement and early growth of the pacific calico scallop Argopecten ventricosus
Coralline algal rhodoliths enhance larval settlement and early growth of the pacific calico scallop Argopecten ventricosus
The features of heterogeneous rhodolith beds (maerl) that contribute to their role as nursery habitats in coastal ecosystems are poorly understood. Rhodoliths are branched, unattached coralline algae that form complex benthic substrates and support diverse communities worldwide. Pacific calico scallops Argopecten ventricosus = circularis (Sowerby II, 1842) occur in high densities in rhodolith beds in the Gulf of California, México. In this study, we found that Lithophyllum margaritae rhodoliths enhanced larval scallop settlement and early post-settlement growth, and examined the settlement cues responsible. In both field and laboratory experiments, larval settlement was significantly higher on (1) rhodolith derived vs. non-coralline sedimentary substrates, (2) living vs. nonliving coralline surfaces, and (3) substrates with higher (whole, branching rhodoliths) vs. lower (rhodolith fragments or sediment) structural complexity. In the field, larval settlement (mean ± SE) onto rhodoliths was 30 to 35 times higher on live rhodoliths (55.0 ± 13.4 and 84.4 ± 8.8 larvae cm-2) than on non-carbonate sediment (1.8 ± 0.8 and 2.4 0.9 larvae cm-2) relative to the surrounding rhodolith or sand habitat, respectively. In a laboratory preference experiment, when comparing live vs. dead coralline surfaces respectively, settlement density was 3.3 times greater (55.8 ± 14.6 vs. 17.0 ± 4.9 larvae cm -2) on whole rhodoliths and 7 times greater (24.2 ± 4.7 vs. 3.4 ± 1.3 larvae cm-2) on fragmented rhodoliths. The strong cueing to live coralline surfaces may have resulted from live coralline algal surfaces or surface biofilms. Growth, presented as post-settlement size, was significantly greater in scallops that settled onto whole vs. fragmented rhodolith substrates for both live (246.6 ± 1.9 vs. 238.9 ± 4.4 μm) and dead (244.2 ± 2.8 vs. 234.7 ± 5.6 μm) coralline surfaces. The structural and coralline cues provided by live, intact rhodoliths and their large-grained sediments contribute to the importance of rhodolith beds as nursery habitats by increasing both scallop settlement and postsettlement growth. Protection of living rhodolith habitats can enhance scallop and other invertebrate populations as well as the sustainability of scallop fisheries by enhancing early life stages. © Inter-Research 2009., Cited By (since 1996):10 Seaweeds, CODEN: MESED
Correlating seabird movements with ocean winds
Correlating seabird movements with ocean winds
Satellite telemetry studies of the movements of seabirds are now common and have revealed impressive flight capabilities and extensive distributions among individuals and species at sea. Linking seabird movements with environmental conditions over vast expanses of the world's open ocean, however, remains difficult. Seabirds of the order Procellariiformes (e.g., petrels, albatrosses, and shearwaters) depend largely on wind and wave energy for efficient flight. We present a new method for quantifying the movements of far-ranging seabirds in relation to ocean winds measured by the SeaWinds scatterometer onboard the QuikSCAT satellite. We apply vector correlation (as defined by Crosby et al. in J Atm Ocean Tech 10:355-367, 1993) to evaluate how the trajectories (ground speed and direction) for five procellariiform seabirds outfitted with satellite transmitters are related to ocean winds. Individual seabirds (Sooty Shearwater, Pink-footed Shearwater, Hawaiian Petrel, Grey-faced Petrel, and Black-footed Albatross) all traveled predominantly with oblique, isotropic crossing to quartering tail-winds (i.e., 105-165° in relation to birds' trajectory). For all five seabirds, entire track line trajectories were significantly correlated with co-located winds. Greatest correlations along 8-day path segments were related to wind patterns during birds' directed, long-range migration (Sooty Shearwater) as well as movements associated with mega-scale meteorological phenomena, including Pacific Basin anticyclones (Hawaiian Petrel, Grey-faced Petrel) and eastward-propagating north Pacific cyclones (Black-footed Albatross). Wind strength and direction are important factors related to the overall movements that delineate the distribution of petrels at sea. We suggest that vector correlation can be used to quantify movements for any marine vertebrate when tracking and environmental data (winds or currents) are of sufficient quality and sample size. Vector correlation coefficients can then be used to assess population-or species-specific variability and used to test specific hypotheses related to how animal movements are associated with fluid environments. © Springer-Verlag 2009., Cited By (since 1996):11 Marine Mammals, Birds & Turtles, CODEN: MBIOA
Coupling propagule output to supply at the edge and interior of a giant kelp forest
Coupling propagule output to supply at the edge and interior of a giant kelp forest
Propagule dispersal is fundamental in regulating the strength of demographic and genetic interactions between individuals both within and among populations. I studied spatiotemporal variability in propagule (zoospore) supply of a continuously reproducing seaweed, giant kelp Macrocystis pyrifera, to examine: (1) the extent to which local zoospore production is coupled to (correlated with) temporal variability in zoospore supply; and (2) spatial variability in the strength of such coupling. Macrocystis pyrifera planktonic zoospores were quantified from seawater samples pumped on numerous dates in 1999 from just above the substratum at various sites in the Point Loma kelp forest, southern California, USA. Zoospore collections were made at a site in the forest interior approximately three times per month from late February through mid-November. Sample collection overlapped with complete demographic surveys of the local population (100 m2) to determine local reproductive output. Temporal variability in zoospore supply was strongly correlated with relative changes in the density .and size structure of local reproductive adult sporophytes; 76% of variability in zoospore supply was explained by local reproductive output. This tight coupling between zoospore supply and local reproduction appeared to be driven by low-displacement, oscillating currents in the forest interior due to the cumulative drag of adult sporophytes, which kept zoospores close to their release site. High coupling between zoospore supply and local reproduction was validated at two additional interior sites separated by 1 km; 78% of variability in zoospore supply was explained by local reproductive output at these sites. Due to lower sporophyte densities, however, the forest edges experienced rapid, unidirectional currents that appeared to transport zoospores far from their release site, effectively decoupling zoospore supply from local reproduction; only 38% of variability in zoospore supply was explained by local reproductive output at these sites. The results suggest that the size of and location within kelp populations is an important determinant of the importance of local reproduction to zoospore supply due to the effects of flow modification by kelp canopies on zoospore dispersal., Cited By (since 1996):27 Seaweeds, CODEN: ECOLA
Cranial movements during suction feeding in teleost fishes
Cranial movements during suction feeding in teleost fishes
Suction is produced during prey capture by most teleost fishes. Here, we ask two questions about the functional basis of suction feeding. First, is there variation in the kinematic pattern produced by different species while suction feeding? Second, do species termed 'suction specialists' demonstrate similar modifications to their feeding behavior? We used 10 kinematic variables in a principal component analysis to identify axes of variation among 14 suction feeding teleost species (representing nine families and five orders within the Euteleostei) that demonstrate different feeding habits and habitats. MANOVA and Tukey post hoc tests were used to assess differences among species. Most species clustered together on the principal component axes, suggesting a generalized mechanism that facilitates unidirectional flow. Typically, only one species stood out as 'extreme' on each functional axis, and a species that stood out on one axis did not stand out on others. Only one species, the flatfish Pleuronichthys verticalis, an obligate benthic feeder, demonstrated modifications consistent with enhanced suction production. This species displayed a suite of changes that should enhance suction production, including large hyoid depression, large cranial rotation, and small gape. We suggest that suction performance may be greatest in such obligate benthic feeders because cranial morphology is highly modified and prey are captured from the substrate. © 2005 Elsevier GmbH. All rights reserved., Cited By (since 1996):27 Fish and Fisheries
Cytometric quantification of nitrate reductase by immunolabeling in the marine diatom Skeletonema costatum
Cytometric quantification of nitrate reductase by immunolabeling in the marine diatom Skeletonema costatum
Background: The uptake of nitrate by phytoplankton is a central issue in biological oceanography due to its importance to primary production and vertical flux of biogenic carbon. Nitrate reductase catalyzes the first step of nitrate assimilation, the reduction of NO'3 to NO 2. A cytometric protocol to detect and quantify relative changes in nitrate reductase (NR) protein content of the marine centric diatom Skeletonema costatum is presented. Methods: Immunolabeling of NR protein was achieved with polyclonal antibodies raised against S. costatum NR. Antisera specific to a NR protein subunit and to a NR polypeptide sequence were compared and cytometric results of NR protein abundance were related to Western analyses. Changes in cellular NR abundance and activity were followed during an upwelling simulation experiment in which S. costatum was exposed to a shift from ammonia to nitrate as major nitrogen source. Results: NR protein could be detected in NO 3-grown cells and at extremely low levels hardly discernible by Western Blot densiometry in NH 4-grown cells. The protocol allowed observation of early stages of NR induction during an upwelling simulation. NR abundance increased after the nutrient shift to reach a new physiological 'steady- state' 96 hrs later. NR activity exhibited diel variation with maxima at mid- day. NR abundance as estimated by both flow cytometry and Western analysis exhibited a hyperbolic relationship to NR activity. This pattern suggests post-translational activation of NR protein. Conclusions: The presented protocol allows the differentiation of NH 4- versus NO 3-grown algae as well as the monitoring of early stages in the induction of nitrate assimilatory capacities. (C) 2000 Wiley-Liss, Inc., Cited By (since 1996):8 Seaweeds, CODEN: CYTOD
Damage and recovery in intertidal Fucus gardneri assemblages following the Exxon Valdez oil spill
Damage and recovery in intertidal Fucus gardneri assemblages following the Exxon Valdez oil spill
Cited By (since 1996):19 Seaweeds, CODEN: MESED, In March 1989, the 'Exxon Valdez' spilled over 10 million gallons (ca 38 million I) of crude oil into Prince William Sound, Alaska , USA. The spill was followed by massive clean-up using hot seawater at high pressure as well as other mechanical and chemical techniques. We studied initial damage and subsequent recovery in the upper margin of the Fucus gardneri assemblage on protected shores by comparing sites that were unoiled, oiled and cleaned with hot water at high pressure, and oiled but less intensely cleaned. F. gardneri cover averaged 80% on unoiled sites but< 1 % on all oiled and cleaned sites 18 mo after the spill. The abundances of barnacles, littorine snails and limpets varied among sites and species, and this variation was associated in part with differences in their life histories. F. gardneri cover was still extremely low on oiled and cleaned sites 2.5 yr after the spill. Holdfasts that persisted after cleaning did not resprout. F. gardneri recruitment was lowest at intensely cleaned sites, and most recruits occurred in cracks near adults. Recruits were less abundant under adult canopies but placing canopies over recruits did not decrease their survivorship over 5 mo. Natural weathering of tar was rapid, with most marked patches gone in less than 1 yr. We conclude that intense mechanical cleaning following this oil spill increased damage and slowed recovery. Such methods should be avoided if reduction of environmental damage is the primary objective of post-spill management decisions. The recovery of F. gardneri at its upper margin might be enhanced by devices that retain moisture and increase substratum rugosity.
Data Report for the Investigation of Bioaccumulation of PCBs in San Francisco Bay
Data Report for the Investigation of Bioaccumulation of PCBs in San Francisco Bay
San Francisco Regional Water Quality Control Board. Oakland CA, USA, 45 pp.

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