Trends Mussel Watch Program Research Articles

What Is Going on with Perkinsus marinus in the Gulf of Mexico?

The National Oceanic and Atmospheric Administration (NOAA) Status and Trends Mussel Watch Program sampled the largest oysters in nearly every major US coastal lagoon and estuary in the Gulf of Mexico once during the winter from 1986 to 2010. This contribution examines trends in the principal oyster disease in the Gulf of Mexico, Dermo, caused by Perkinsus marinus, and some related population dynamic characteristics for its host, Crassostrea virginica. During the 1986–2000 period, P. marinus prevalence and infection intensity and oyster population dynamics followed the El Nino-Southern Oscillation (ENSO) cycle, responding to variations in salinity caused by variations in rainfall and freshwater inflow. The ENSO signal in the oyster population effectively ceased circa 2002. Beginning around this time, wintertime P. marinus prevalence and weighted prevalence began a decadal decline, as did the length of the largest oysters and the fraction of these largest animals that were female. The trends in Dermo disease, oyster length, and oyster sex ratio are all consistent with the following hypothesis: increasing temperature during the 2000s resulted in an increase in P. marinus infection intensity sufficient to increase the mortality rate in late summer and fall in the larger animals. This simultaneously reduced Dermo prevalence and infection intensity in the winter at the time of sampling and also resulted in the decline in the length of the largest animals targeted by Mussel Watch. Coincident with the decline in length is the expected decline in the fraction female, such that the percent female in the largest animals dropped to ≤50 % throughout much of the Gulf of Mexico. The decline in length leading to fewer large animals reproducing and the loss of females are predicted to have reduced oyster population reproductive capacity substantially during the 2000s. The early 60 % of the Mussel Watch time series took place during a period of negative Atlantic Multidecadal Oscillation (AMO) indices. The AMO moved into positive territory circa 2000. A positive AMO index is consistent with observed warmer water temperatures, and increased water temperature is consistent with an increase in Dermo-induced mortality.

Temporal Structure and Trends of Parasites and Pathologies in U.S. Oysters and Mussels: 16 Years of Mussel Watch

ABSTRACT Parasites and pathologies of oysters and mussels were sampled yearly from 1995 to 2010 from the Gulf of Maine to Alaska and the Great Lakes as part of the National Oceanic and Atmospheric Administration Status and Trends Mussel Watch Program. Sentinel bivalves included mytilid mussels, dreissenid mussels, and oysters. This comprehensive dataset provides a unique opportunity to examine long-term temporal dynamics of parasites, pathologies, and physiological indices of these sentinel bivalves. Temporal dynamics fell into a few clear categories. Significant differences between years occurred commonly for parasites, pathologies, and physiological indices; the absence of significant change over time was more noteworthy. In a few cases, these trends were characterized by multiyear increases or decreases in value within the time series. Such behavior might be produced by a multiyear cycle and, in fact, such behavior was much more common along the southern East Coast, the Gulf Coast, and Southern Califor...

Assessment of coastal storm impacts on contaminant body burdens of oysters collected from the gulf of Mexico

This study evaluated changes in oyster tissue contaminant levels following North Atlantic tropical cyclones to determine if changes in contaminant concentrations were predictable. The basis for this study was analysis of coastal chemical contaminant data from the National Oceanic and Atmospheric Administration's (NOAA) National Status and Trends Mussel Watch Program and NOAA's National Weather Service storm track data. The tendency for contaminant (metals and organic compounds) body burdens to increase or decrease in oyster tissue after a storm was assessed using contingency and correspondence analyses. Post-storm contaminant levels in oysters revealed a consistent pattern of distribution, which could be described as follows: (1) most of the organic contaminants stay within their long-term concentration ranges, (2) very few organic contaminants decreased, and (3) metals overwhelmingly tend to increase.

Chemical contamination of the Hudson-Raritan Estuary as a result of the attack on the World Trade Center: Analysis of polycyclic aromatic hydrocarbons and polychlorinated biphenyls in mussels and sediment

The September 11, 2001 attack on the World Trade Center (WTC) resulted in a massive plume of dust and smoke that blanketed lower Manhattan and part of the Hudson-Raritan Estuary (HRE). The NOAA National Status and Trends Mussel Watch Program has long-term monitoring sites in the area and thus had an opportunity to assess the effect of the WTC attack on PAH and PCB contamination of the surrounding estuary. Seven additional sites were added in the Upper HRE to attain higher sampling resolution for comparison with regularly sampled Mussel Watch Project HRE sites. Elevated background levels of PCBs and PAHs in mussel tissue and sediments were high enough before the WTC attack that concentrations were not measurably changed by WTC derived contaminant input.

Mussels document loss of bioavailable polycyclic aromatic hydrocarbons and the return to baseline conditions for oiled shorelines in Prince William Sound, Alaska

Polycyclic aromatic hydrocarbons (PAH) were measured in mussels (Mytilus trossulus) collected between 1990 and 2002 from 11 sites on the shores of Prince William Sound (PWS), Alaska, that were heavily oiled by the 1989 Exxon Valdez oil spill (EVOS). This study, utilizing the methods of the NOAA Status and Trends Mussel Watch Program, found that concentrations of PAH released from spill remnants have decreased dramatically with time and by 2002 were at or near the range of total PAH (TPAH) of 3-355 ng/g dry weight obtained for mussels from unoiled reference sites in PWS. Time-series TPAH data indicate a mean TPAH half-life in mussel tissues of 2.4 years with a range from 1.4 to 5.3, yielding an annual mean loss of bioaccumulated TPAH of 25%. The petroleum-derived TPAH fraction in mussel tissues has decreased with time, reflecting the decreasing release of EVOS residues in shoreline sediments. These results show that PAH from EVOS residues that remain buried in shoreline sediments after the early 1990s are in a form and at locations that have a low accessibility to mussels living in the intertidal zone.

The geographic distribution of population health and contaminant body burden in gulf of Mexico oysters.

As part of NOAA's National Status and Trends Mussel Watch Program, oysters were sampled along the Gulf of Mexico coast each winter from 1986 to 1993 (The present analysis deals with 1986-1993 Mussel Watch data; the Mussel Watch project itself continues at this printing) and analyzed for trace metal, polynuclear aromatic hydrocarbons and pesticide body burden, plus a series of biological variables designed to assess population status and health. We identified contaminant and biological variables in which large-scale spatial processes played an important role in establishing population values by examining the likelihood that neighboring bays tended to have populations with body burdens or population attributes more similar than expected by chance. Local or watershed-dependent factors, such as land use and freshwater inflow, are important in controlling the bay-to-bay variation in body burden in most contaminants. However, the bay-to-bay variations in body burden of some metals (As, Cd, Hg, Ni, Se) appear to be principally influenced by larger-scale climatic factors. These metals and the biological variable shell length demonstrated a strong degree of similarity between bays over a large regional area reminiscent of the pattern shown by climatic factors, such as temperature and precipitation. In contrast, among the organics, none of the PAHs showed even a moderately strong climatic signal. Among the pesticides, only two did (dieldrin, total DDTs). These pesticides and the biological variables, reproductive stage and Perkinsus marinus prevalence and infection intensity, had spatial patterns that suggested both a local and a regional influence to their geographic distributions. This same pattern is exhibited by freshwater runoff. Metal contaminants also behaved distinctively compared to organics in the temporal influence of climate in establishing the interannual variability in body burden. For the organics, trends in interannual variability were strongly influenced by climate, whereas spatial trends were not. In contrast, most metals were unaffected by climatic forcing both spatially and temporally. However, all of the metals having a spatial pattern strongly influenced by climate (As, Cd, Hg, Ni, Se) also exhibited interannual variations related to variations in climate.

A survey of oysters Crassostrea virginica from Tampa Bay, Florida: associations of internal defense measurements with contaminant burdens

Oysters from 16 sites in Tampa Bay, Florida, were collected during a 6-week period in winter 1993 and analyzed for both biological characteristics and tissue chemical concentrations. Using previous sediment contamination and toxicity data, oyster tissues from the selected sites were expected to exhibit a wide range in both quantity and type of chemicals. Chemical analysis showed tissue concentrations at some of these sites to be greater than national averages, as reported by the National Status and Trends Mussel Watch Program, for total PAH, total PCB, total chlordanes, DDT, Cu, Pb and Zn. Measures of oyster internal defense, including hemocyte density, rate of locomotion and superoxide generation, varied significantly among sites and were generally higher at sites with higher tissue concentrations of xenobiotic chemicals. Potential associations between oyster defense characteristics and accumulated chemical contaminants, either singly or in chemical classes, were explored using correlation analysis and a composited ranking procedure. Positive relationships were found for hemocyte characteristics with certain trace metal (Cu, Sn and Zn) and PAH analytes, whereas negative relationships were found with certain PCB and pesticide analytes. Heightened defenses in contaminated conditions may reflect a hemocyte process for sequestration and detoxification of environmental contaminants. Oysters from four of the 16 sites were additionally collected in June and September 1993 and site-related differences did not closely parallel those obtained in winter. Seasonal environmental factors may have altered contaminant-related differences among sites.

Influence of climate change on interannual variation in contaminant body burden in Gulf of Mexico oysters

As part of NOAA's National Status and Trends Mussel Watch Program, oysters were sampled along the Gulf of Mexico coast each winter from 1986 to 1992 and analyzed for trace metal, polynuclear aromatic hydrocarbon (PAH), and pesticide body burden. We identified contaminant variables for which large-scale climate processes played an important role in establishing the interannual variation in body burden by examining cases where body burdens rose or fell more or less in unison over broad geographic regions and distinguished these concordant changes from cases where bays varied independently. Of the 11 metals analyzed, nine had scales of concordancy ⩽100 km. Ni and Se, however, had among the largest scales of concordancy in the study, ⩾1200 km. That is, oyster body burdens in bays as far apart as 1200 km tended to rise and fall in unison from one year to the next. Interannual variations in body burden of organic contaminants had a much stronger regional component. All but two of the 11 organic contaminants had scales of concordancy of 200 km or greater and six exceeded 400 km. Concordancy was strongest either in the southern, northwestern, or north-central Gulf, depending upon the contaminant. For all contaminants, bays tended to vary independently in the northeastern Gulf. For three contaminants, total chlordanes, dieldrin and Cd, regional concordancy may originate from a widespread decrease in use and, therefore, input. These contaminants declined nearly monotonically over the 7 years. For others, including Zn and many of the PAHs and pesticides, the El Niño/Southern Oscillation (ENSO) cycle may be important in establishing the interannual variability in contaminant body burden: (1) ENSO has the geographic scale required; (2) a subtropical influence is required to explain the similarity in interannual variation between south Texas and southern Florida; (3) ENSO-related climate responses in the Gulf follow the southwestern/northeastern trend that would establish the northwestern Gulf focus in concordancy so prominent in many of the contaminants; and (4) deviations in yearly mean body burden from the Gulf-wide mean track the Southern Oscillation Index in some cases.

U.S. Mussel Watch Data from 1986 to 1994: Temporal Trend Detection at Large Spatial Scales

National Mussel Watch Programs collect bivalves at many sites along their respective coastlines in order to assess chemical contamination of coastal waters. This paper aims at detecting temporal trends at large spatial scales using contaminant data from 1986 to 1994 of the U.S. National Status and Trends Mussel Watch Program. U.S. coasts are divided into 10 large areas. After a logarithmic transformation of the data, linear models are used and include a ‘sampling site' effect, a linear trend estimated for each area, weather covariates, and an ‘analysis' effect reflecting changes of analytical procedures or even laboratories. Except for the Californian coast, chlorinated organic compounds show rather uniform decreases, which can be attributed to bans put on these contaminants. A few increasing trends were detected for trace elements, which also showed few decreases. Additions of weather covariates and possible analysis effects were intended to model apparently random between-year variations in contaminant time−series. Although low in terms of percent age of variability explained, the addition of these effects might have avoided the detection of spurious trends for some contaminants.

Environmental Statistics, Assessment, and Forecasting.

Uncertainties in Assessing the State of the Environment: An Overview of Environmental Statistics Assessment and Forecasting (C.R. Cothern and N.P. Ross). Combining Data and Data Uncertainty: Introduction (C.R. Cothern). Uncertainty Issues of the Hanford Environmental Reconstruction Project (R.O. Gilbert and J.C. Simpson). Decreased Sampling Costs and Improved Accuracy with Composite Sampling (S.D. Edland and G. van Belle). Environmental Chemistry, Statistical Modeling and Observational Economy (G.P. Patil, S.D. Gore, and A.K. Sinha). Predictive Models of Fish Response to Acidification: Using Bayesian Interence to Combine Laboratory and Field Measurements (W.J. Warren-Hicks and R.L. Wolpert). A New Approach for Accommodation of Below Detection Limit Data in Trend Analysis (N.N. Nagaraj and S.L. Brunenmeister). Spatial Chemostatistics: Introduction (N.P. Ross). Spatial Chemostatistics (N. Cressie). Design of the Clean Air Act Deposition Monitoring Network (D. Holland, R. Baumgardner, T. Haas, and G. Oehlert). Considerations in the Analysis of National Air Quality and Emissions Trends Report (B.A. Beard and W.P. Freas). Models and Data Interpretation: Introduction (D. Krewski). Statistical Issues for Development Toxicity Data (D.W. Gaylor). Measuring Carcinogenic Potency (M.J. Goddard, D. Krewski, and Y. Zhu). Environmental Pollution and Human Health: An Epidemiology Perspective (J. Schwartz). Soil Quality as a Component of Environmental Quality (M.A. Cole). Future Environmental Management: Introduction (J. Abe). Gauging the Future Challenges for Environmental Management: Some Lessons from Organization with Effective Outlook Capabilities (M. Boroush). Creating Strategic Visions (C.W. Taylor). Exploring Future Environmental Risks (D.W. Rejeski). Geographic Information Systems (GIS): Introduction (A.M. Pesachowitz). Geographic Information Systems (GIS) for Environmental Decision Making (A.M. Pesachowitz). Mechanisms to Access Information about Spatial Data (E.J. Christian and T.L. Gauslin). Environmental Statistics: Introduction (B. Nussbaum). The Quality of Environmental Databases (D.A. Marker and S. Ryaboy). The National Oceanic and Atmospheric Administration (NOAA) National Status and Trends Mussel Watch Program: National Monitoring of Chemical Contamination in the Coastal United States (T.P. O'Connor). Some Problems of Safe Dose Estimation (A.P. Basu, G.F. Krause, K. Sun, M. Ellersieck, and F.J. Mayer, Jr.). Where Next? Adaptive Measurement Site Selection for Area Remediation (H.T. David and S. Yoo). The Center for Environmental Statistics: Interim Status and Vision of Products (B. Niemann, C. Curtis, and E. Leonard). Conclusion: Environmental Statistics: Where Do We Go from Here? (N.P. Ross and C.R. Cothern). Index.

The Distribution of Perkinsus marinus in Gulf Coast Oysters: Its Relationship with Temperature, Reproduction, and Pollutant Body Burden

AbstractOysters from 48 Gulf of Mexico sites were examined for presence and infection intensity of the endoparasite, Perkinsus (= Dermocystidium) marinus (Mackin, Owen and Collier, 1950) as part of NOAA's Status and Trends Mussel Watch Program. Prevalence exceeded 75% at 25 sites. Infection intensity did not vary with sex or reproductive stage. Latitude, total polynuclear aromatic hydrocarbon (PAH) content and industrial and agricultural land use significantly affected the parasite's distribution. PAH and pesticide concentrations were latitudinally dependent, suggesting an impact of spawning frequency on uptake and depuration. P. marinus analysis complements the use of pollutant body burden for determining change in environmental quality because it responds differently than pollutant body burden to the biology and ecology of the oyster.

NOAA's status and trends mussel watch program: Chlorinated pesticides and PCBs in oysters ( Crassostrea virginica) and sediments from the Gulf of Mexico, 1986–1987

Chlorinated pesticides and PCBs were analyzed in more than 590 oyster and sediment samples collected during 1986 and 1987, the first 2 years of the NOAA's Status and Trends Mussel Watch Program established to monitor the current status and temporal trends of these contaminants in the Gulf of Mexico. Chlorinated hydrocarbons in oysters and sediments presented similar distribution patterns; however, their concentrations in oysters were several times higher than the concentration detected in the surrounding sediments. Alpha-chlordane, trans-nonachlor and dieldrin were the most abundant non-DDT pesticides in both types of sample. The major fraction of DDT related compounds measured in oysters and sediments was DDD. Based on average PCB concentrations, penta-, hexa-, and tetrachlorobiphenyls were preferentially accumulated by oysters as compared to the average sediment composition. Although this study was designed to avoid known point-sources of contaminant inputs, the measured concentrations were, in general, within the range of concentrations previously reported for the Gulf of Mexico. After the first 2 years of this program, the geographical distribution of chlorinated hydrocarbons in oysters and sediments is well defined. In contrast, the temporal trends at the different sites are not clear. Continued sampling will allow the identification of long-term trends in concentrations of chlorinated hydrocarbons in the Gulf of Mexico.