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Baseline for beached marine debris on Sand Island, Midway Atoll
2012
Ribic, Christine A. | Sheavly, Seba B. | Klavitter, John
Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008–July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4kg. Seventy-two percent of the total was pieces; 91% of the pieces were made of plastic materials. Pieces were composed primarily of polyethylene and polypropylene. Identifiable items were 28% of the total; 88% of the identifiable items were in the fishing/aquaculture/shipping-related and beverage/household products-related categories. Identifiable items were lowest during April–August, while pieces were at their lowest during June–August. Sites facing the North Pacific Gyre received the most debris and proportionately more pieces. More debris tended to be found on Sand Island when the Subtropical Convergence Zone was closer to the Atoll. This information can be used for potential mitigation and to understand the impacts of large-scale events such as the 2011 Japanese tsunami.
Show more [+] Less [-]Environmental factors responsible for the incidence of antibiotic resistance genes in pristine Crassostrea virginica reefs
2012
Barkovskii, Andrei L. | Thomas, Michael | Hurley, Dorset | Teems, Clifford
The occurrence of tetracycline resistance (TRG) and integrase (INT) genes were monitored in Crassostrea virginica oyster reefs of three pristine creeks (SINERR, Georgia, USA). Their profiles revealed 85% similarity with the TRG/INT profiles observed in the adjacent to the SINERR and contaminated Altamaha River estuary (Barkovskii et al., 2010). The TRG/INT spectra and incidence frequencies corresponded to the source of oceanic input and to run-offs from creeks’ watersheds. The highest incidence frequencies and concentrations were observed in oysters. TRG/INT incidences correlated positively (Spearman Rank=0.88), and negatively correlated (−0.63 to −0.79) with creek salinity, conductivity, dissolved solids, and temperature. Coliform incidence positively correlated with temperature, and not with the TRG/INT incidence. The Altamaha River estuary was the primary TRG/INT source for the reefs with contributions from creek’s watersheds. TRG/INT were carried by non-coliforms with a preference for low-to-temperate thermohaline environments coupled with bioaccumulation by oysters.
Show more [+] Less [-]Effects of chlorpyrifos on cholinesterase activity and stress markers in the tropical reef fish Acanthochromis polyacanthus
2012
Botté, E.S. | Jerry, D.R. | Codi King, S. | Smith-Keune, C. | Negri, A.P.
Tropical coastal ecosystems, including the Great Barrier Reef (GBR) of Australia are increasingly threatened by pollution; yet few studies have investigated the sensitivity of GBR species to these pollutants. Here we exposed juveniles of the tropical reef fish Acanthochromis polyacanthus (spiny damselfish) to three concentrations of the insecticide chlorpyrifos (CPF) and measured (i) muscle cholinesterase (ChE) activity; (ii) hepatic glutathione-S-transferase (GST) activity; and (iii) coenzyme Q (CoQ) redox balance, after 6h and 96h of exposure. After 96h, muscle ChE activity was significantly inhibited by 26%, 49% and 53% when fish were exposed to 1, 10 or 100μg/L CPF, respectively. Muscle ChE characterization revealed three types of ChEs, including two atypical forms. Hepatic CoQ antioxidant form significantly increased at 10μg/L after 6h of exposure, potentially demonstrating an early response to CPF-induced oxidative stress in liver. Hepatic GST was not affected by CPF exposure.
Show more [+] Less [-]Quantifying the sources of pollutants in the Great Barrier Reef catchments and the relative risk to reef ecosystems
2012
Waterhouse, J. | Brodie, J. | Lewis, S. | Mitchell, A.
Development of the Great Barrier Reef (GBR) catchments in the last 150years has increased the loads of suspended sediment, nutrients and pesticides (‘pollutants’) delivered to the GBR. The scale and type of development, the pollutants generated and the ecosystems offshore vary regionally. We analysed the relative risk of pollutants from agricultural land uses and identified the sources of these pollutants from different land uses for each region to develop priorities for management. The assessment showed the Wet Tropics and Mackay Whitsunday regions to be of relatively high risk dominated by sugarcane cultivation, contributing pesticide and dissolved inorganic nitrogen (DIN). The Burdekin and Fitzroy ranked medium–high risk dominated by grazing suspended sediment inputs for both, and additionally sugarcane DIN and pesticide inputs for the Burdekin. The Burnett Mary ranked medium risk, dominated by grazing and sugarcane. Cape York was not formally ranked but is considered to be low risk.
Show more [+] Less [-]Elevated ammonium concentrations from wastewater discharge depress primary productivity in the Sacramento River and the Northern San Francisco Estuary
2012
Primary production in the Northern San Francisco Estuary (SFE) has been declining despite heavy loading of anthropogenic nutrients. The inorganic nitrogen (N) loading comes primarily from municipal wastewater treatment plant (WTP) discharge as ammonium (NH₄). This study investigated the consequences for river and estuarine phytoplankton of the daily discharge of 15 metric tons NH₄–N into the Sacramento River that feeds the SFE. Consistent patterns of nutrients and phytoplankton responses were observed during two 150-km transects made in spring 2009. Phytoplankton N productivity shifted from NO₃ use upstream of the WTP to productivity based entirely upon NH₄ downstream. Phytoplankton NH₄ uptake declined downstream of the WTP as NH₄ concentrations increased, suggesting NH₄ inhibition. The reduced total N uptake downstream of the WTP was accompanied by a 60% decline in primary production. These findings indicate that increased anthropogenic NH₄ may decrease estuarine primary production and increase export of NH₄ to the coastal ocean.
Show more [+] Less [-]Mercury levels in feathers of Magellanic penguins
2012
Frias, Jorgelina E. | Gil, Mónica N. | Esteves, José L. | García Borboroglu, Pablo | Woods, Olivia Jessica | Smith, Jeff R. | Boersma, P Dee
Feathers are useful to determine mercury (Hg) contamination. We evaluated the mercury concentration in feathers of Magellanic penguins (Spheniscus magellanicus) age 1.5years to 25years at Punta Tombo, Argentina before and during their molt. Mercury ranged between <1.4 and 367ng/gdryweight, with three extreme high values (8996ng/g, 3011ng/g and 1340ng/g) all in young adults. The median concentration was lowest for juveniles and significantly higher for adults but with high variation among older adults. Males and females had similar mercury loads. Compared with other penguin species, concentrations in Magellanic penguins were low. Mercury levels for Magellanic penguins in the Southwest Atlantic for older adults averaged 206±98ng/g, and serve as a baseline for biomonitoring and/or ecotoxicological studies.
Show more [+] Less [-]Effects of prolonged entanglement in discarded fishing gear with substantive biofouling on the health and behavior of an adult shortfin mako shark, Isurus oxyrinchus
2012
Wegner, Nicholas C. | Cartamil, Daniel P.
A mature male shortfin mako, Isurus oxyrinchus, was captured with a three-strand twisted natural fiber rope wrapped around the body causing deep abrasions, scoliosis of the back, and undernourishment. Fifty-two pelagic peduculate barnacles from four species were found fouling on the rope. Assuming larval settlement occurred following entanglement, barnacle growth-rate data suggest the rope had been around the shark for at least 150days. However, the onset of severe scoliosis (likely linked to the increased constriction of the rope with growth and the added drag induced by biofouling) indicates that this rope may have been in place much longer. Following removal of the rope, a pop-up satellite archival tag was attached to the shark to assess post-release health. The resulting 54days of tag deployment data show that despite its injuries, the shark survived, and following an initial stress period, exhibited movement patterns characteristic of healthy makos.
Show more [+] Less [-]Radionuclide monitoring in molluscs inhabiting intertidal region near a nuclear installation, Gulf of Mannar, India
2012
Feroz Khan, M. | Godwin Wesley, S.
Protection of non-human biota from ionizing contaminants, especially in the vicinity of nuclear installations is a very important aspect for nuclear engineers and ecologists. In this view, a baseline data on the activity concentration of ²¹⁰Po and ²¹⁰Pb were quantified in different tissues of molluscs inhabiting the intertidal region along the coast of Kudankulam. The activity concentration was noticed higher in the organs associated with digestion and metabolism. Filter feeding bivalve molluscs registered the maximum activity of ²¹⁰Po in their whole body compared to grazing gastropods. ²¹⁰Po:²¹⁰Pb ratio was calculated to be greater than unity in most of the analysed tissues. The ecological sensitivity of molluscs to the radiation exposure and the safeness of the environment was analysed by calculating the external and internal dose rate. The hazard quotient for molluscs was lesser than the global bench mark dose rate of 10μGyh–¹.
Show more [+] Less [-]Real-time PCR and NASBA for rapid and sensitive detection of Vibrio cholerae in ballast water
2012
Fykse, Else M. | Nilsen, Trine | Nielsen, Agnete Dessen | Tryland, Ingun | Delacroix, Stephanie | Blatny, Janet M.
Transport of ballast water is one major factor in the transmission of aquatic organisms, including pathogenic bacteria. The IMO-guidelines of the Convention for the Control and Management of Ships’ Ballast Water and Sediments, states that ships are to discharge <1CFU per 100ml ballast water of toxigenic Vibrio cholerae, emphasizing the need to establish test methods. To our knowledge, there are no methods sensitive and rapid enough available for cholera surveillance of ballast water. In this study real-time PCR and NASBA methods have been evaluated to specifically detect 1CFU/100ml of V. cholerae in ballast water. Ballast water samples spiked with V. cholerae cells were filtered and enriched in alkaline peptone water before PCR or NASBA detection. The entire method, including sample preparation and analysis was performed within 7h, and has the potential to be used for analysis of ballast water for inspection and enforcement control.
Show more [+] Less [-]²¹⁰Po and ²¹⁰Pb variations in fish species from the Aegean Sea and the contribution of ²¹⁰Po to the radiation dose
2012
Mat Çatal, Ebru | Uğur, Aysun | Özden, Banu | Filizok, Işık
In recent years, there has been increasing interest in the significance of natural radionuclides, particularly ²¹⁰Po, in the marine environment. ²¹⁰Po, a naturally occurring alpha emitter, accumulates in marine organisms and reflects differences in their diets. In the literature, there is no data for ²¹⁰Po and ²¹⁰Pb activity concentrations for fish species on the Turkish coast of Aegean Sea. Therefore, in this study, multiple fish species were collected from six stations seasonally on the Turkish coast of Aegean Sea and were analyzed for their ²¹⁰Po and ²¹⁰Pb content. The ²¹⁰Po and ²¹⁰Pb concentrations in the fish samples were found to vary from undetectable levels to 499±44Bqkg⁻¹ dry weight (dw) and from 1.0±0.3Bqkg⁻¹ to 35±4.0Bqkg⁻¹ (dw), respectively. There were no significant differences in the activity concentrations of ²¹⁰Po and ²¹⁰Pb in fish samples between seasons (ANOVA, P>0.05). The highest dose contribution of ²¹⁰Po to humans was calculated to be 10,530μSvyear⁻¹.
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