Progress 09/01/08 to 08/31/10
Outputs
OUTPUTS: A primary objective of this research was to assess the extent and quality of current oyster habitat (particular emphasis on New Haven and Norwalk harbors, public and private leased beds) and to identify new (underutilized) areas along the CT coast that may also provide suitable oyster habitat. Results of this study were disseminated to communities of interest in a variety of ways. Oral and poster presentations were presented by participating faculty and students at the 10th Biennial Long Island Sound Research Conference at UCONN Stamford, October 29-30, 2010. Over 100 regional scientists, educators and regulatory agencies attended the symposia. The oyster research was featured in a special session of the 13th Annual Connecticut State University Faculty Research Conference, Central Connecticut State University, April 17, 2010. Four oral presentations were delivered concerning the phytoplankton abundance in Long Island Sound, oyster habitat quality and tissue metals, and the characterization of solar radiation with application toward understanding the causes of hypoxia. The phytoplankton abundance and diversity study was presented at the 2009 Benthic Ecology Meeting, Corpus Christi, TX. The phytoplankton, pathology and tissue metal studies were presented at the 30th Annual Milford Aquaculture Seminar, February 8-10, 2010. The Milford Aquaculture Seminar is one of the primary vehicles for communicating information to the aquaculture industry, the scientific community, and the public. An abstract concerning oyster tissue mercury contents was submitted for presentation at the 31st Annual Milford Aquaculture Seminar, February 2011. Results of the research concerning oyster tissue metals was featured in an article in The Dredge, a publication of the Connecticut Sea Grant Extension and targeted to the oyster industry. Elements of the research program were incorporated into undergraduate and graduate biology, marine studies, environmental education, meteorology and oceanography courses taught by the various PIs at three Connecticut State University campuses (Central, Southern and Western). Descriptions of the faculty-mentored student research projects are available online and may be accessed via the Center for Coastal and Marine Studies at SCSU at http://www.southernct.edu/departments/ccms/ studentprojects.html. One graduate student Masters thesis has been completed and we anticipate two additional Masters theses will be completed in 2011. One of the project goals was to develop a curriculum to create awareness of oysters in Long Island Sound. The objective was to create lessons to allow students to explore the ecology and commercial importance of the oyster fishery in the state of Connecticut. The oyster curriculum was presented at the Southeastern New England Marine Educators (SENEME) Conference, Project Oceanology, UCONN, Groton, CT on October 16, 2010. Educators were able to review and discuss the teaching materials and register to receive a final PDF copy of the curriculum for use in the classroom. PARTICIPANTS: Principal Investigators (PI/PDs): Dr. Vincent T. Breslin (SCSU) coordinated the overall project management and the oyster tissue metals and oyster pathology studies. Dr. James Tait (SCSU) coordinated sediment grain-size sampling and analyses and also the side-scan sonar studies along with Dr. Suzanne O'Connell (Wesleyan University). Dr. Dwight Smith (SCSU), in association with Mr. Joseph Schnierlein (Maritime Aquarium at Norwalk), developed educational outreach activities. Drs. Clayton Penniman and Jerry Jarrett (CCSU) conducted the microbiological studies and oyster larvae viability studies at low levels of dissolved oxygen. Dr. Sean Grace (SCSU) coordinated the phytoplankton characterization studies. Dr. James Boyle (WCSU) made measurements to characterize surface energy budgets in the Norwalk Harbor region. Five graduate students and six undergraduates participated in the research and outreach activities. Graduate Students: David Oshana (SCSU oyster tissue metals), Neil Geist (SCSU oyster pathology), Melissa Krisak (SCSU phytoplankton studies), Michelle Masse-Allen (SCSU educational outreach), and Jennifer Gunther (CCSU microbiological studies). Undergraduate Students: Karen Thomas (SCSU oyster tissue metals), Victoria Church (SCSU harbor sediment metals), Mary LeVallee (SCSU oyster tissue metals), Steven Schmidt (WCSU radiation studies), Rosemary Ostfeld (Wesleyan University side-scan sonar) and Jebediah Stevens (SCSU sediment grain size analyses). Partner Organizations and Collaborators: Wesleyan University, Sound School Regional Vocational Aquaculture Center, New Haven, CT, Maritime Aquarium at Norwalk, Norwalk, CT. Many collaborators assisted with the collection of the oysters and sediments from commercial and recreational oyster beds including representatives from the following organizations: Project Oceanology, Groton, CT, the Cedar Island Marine Laboratory, Clinton, CT, Norm Bloom and Son, Norwalk, CT and Aeros Cultured Oysters, Noank, CT. Inke Sunila, Bureau of Aquaculture, Milford CT and Gary Wikfors, NOAA National Marine Fishery Laboratory, Milford, CT provided expertise and laboratory space in support of the pathology and phytoplankton studies, respectively. TARGET AUDIENCES: The Connecticut Bureau of Agriculture, Bureau of Aquaculture, commercial and recreational oyster fisherman, NOAA Fisheries Northeast Fisheries Science Center, Milford Laboratory, Connecticut Sea Grant, research scientists, the Connecticut Department of Environmental Protection, Public School and Outreach Program Educators, and students K-12. PROJECT MODIFICATIONS: Initially, plankton samples were collected via tow net at each study site once per season and quantified via microscopy. This approach proved useful in analyzing the phytoplankton community of larger particle sizes, where site and seasonality could be compared. It did not however, answer the question of phytoplankton availability for oysters. To better address this question, phytoplankton sampling methods were modified. A van Dorn bottle was used to collect a sample from the water column during the fall 2009 and spring 2010 blooms. These samples were analyzed in a flow cytometer for particle size and abundance. The plankton community can fluctuate greatly within a day, and while the cytometric analysis gave an indication of abundance and size, oyster tissues were also analyzed for glycogen levels. Changes in glycogen levels occur at a much slower rate and are a secondary indication of food abundance availability. Since energy is stored in the form of glycogen oysters were collected in the fall to analyze how much energy had been stored in tissue before entering quiescence. Oysters were collected before quiescence ended in the spring to analyze the use of glycogen over time. Preliminary results showed that glycogen did decrease over this period of time, indicating that the fall bloom was the period of time when oysters can increase stored energy before entering quiescence.
Impacts
Results of this study have contributed to our understanding of the environmental quality of oyster habitat along the Connecticut coastline. The thirteen oyster sites examined in this study were characterized by a variety of sediment types with wide ranging sediment metal concentrations. Sediment habitats ranged from fine-grained (high silt/clay content) high iron content sediment to coarse-grain (low silt/clay content) low iron content sediment. Furthermore, sediment contaminant metals were comparatively higher in fine-grained sediment. Relationships between sediment grain size, metal contents and loss on ignition data were correlated using a multivariate model to prepare geo-referenced maps of sediment habitats in New Haven and Norwalk harbors. These maps, along with the oyster habitat characterization databases, will allow for the identification of suitable or impaired oyster habitat. Sediment quality characteristics were also correlated with tissue metal concentrations and pathologies associated with oysters growing in those locations. Oyster tissue metal concentrations did not show a direct correlation with high sediment metal concentrations indicating that sediment metals are not the sole source of metals accumulated by oysters. However, results of our study demonstrated an inverse relationship between oyster tissue copper, cadmium and zinc with ambient salinity for CT oysters sampled in November 2008. The background pathology of previously observed infectious agents common to Long Island Sound (LIS) oysters was observed, however no trends could be associated with tissue or sediment metals measured in this study. Radiometer measurements made in this study supplement existing energy budget monitoring programs and provide specific information relevant to the Norwalk Harbor region. The in-situ measurements, along with historical data from the National Solar Radiation Data Base for the LIS region as well as archived MYSOUND moored buoy data, were acquired and analyzed. The radiation measurements provide a better understanding of solar radiation, cloud cover and general meteorological conditions over LIS supporting a determination of the relative importance of physical processes as compared to chemical processes (nitrogen loading) and biological influences on the condition of hypoxia. This information will be of importance to environmental managers and scientists involved in characterizing and mitigating LIS hypoxia. A curriculum focusing on the ecology and commercial importance of the oyster fishery in the state of Connecticut was developed. The curriculum, linked to literacy standards, provides educational opportunities for teachers and students to explore the science, history, geography, mathematics and language arts through the study of the Eastern oyster. Results of this project have been communicated to scientists and resource managers at local and regional professional meetings. Results have also been communicated to the Connecticut Department of Agriculture, Bureau of Aquaculture for decision making related to the quality of oysters and oyster habitat.
Publications
- 1. Krisak, M., Allen, M. and D.G. Smith. The great debate: Whats good for oysters, oysterman and us Connecticut Journal of Science Education. In press. 2. Allen, M. and D.G. Smith. 2010.
- Long Island Sound Curricula. Connecticut Journal of Science Education, 47 (2): 27-33.
- 3. Concepcion, A. 2010. Researchers Seek Answers about Heavy Metals and Shellfish. The Dredge, 4(2): 1-5. Spring, 2010.
- 4. Conklin, J. and Breslin, V.T. 2010. Metal concentrations in the sediment of the lower Housatonic River estuary. Abstracts of Technical Papers of the Milford Aquaculture Seminar, February 8-10, 2010.
- Journal of Shellfish Research, 29(2): 547. 5. Geist, G.N., Oshana, D., Sunila, I., and Breslin, V.T. 2010. Prevalence of disease, growth abnormalities and tissue metal contents in Eastern oysters along the Connecticut coastline. Abstracts of Technical Papers of the Milford Aquaculture Seminar, February 8-10, 2010.
- Journal of Shellfish Research, 29(2): 551. 6. Oshana, D. 2010. Spatial Trends in Eastern Oyster (Crassostrea virginica) Tissue Metal Concentrations in Long Island Sound. MS Thesis, Southern Connecticut State University, New Haven, CT. December, 2010. 94 pp. 7. Krisak, M. and S. Grace. 2010.
- An Examination of Phytoplankton Abundance and Diversity with Relation to Physical Factors in Long Island Sound. Book of Abstracts, 13th Annual Connecticut State University Faculty Research Conference, Central Connecticut State University, New Britain, CT. April 17, 2010. pg. 19. 8. Tait, J., J. Stevens, OConnell S., and Ostfeld, R. 2010.
- Synoptic Reconnaissance of Oyster Habitat in Connecticut Harbors. Book of Abstracts, 13th Annual Connecticut State University Faculty Research Conference, Central Connecticut State University, New Britain, CT. April 17, 2010. pg. 40. 9. Breslin, V.T., D. Oshana, N. Geist, K. Thomas, and M. LaVallee. 2010.
- Habitat Quality, Prevalence of Disease and Tissue Metals in Eastern Oysters along the Connecticut Coastline. Book of Abstracts, 13th Annual Connecticut State University Faculty Research Conference, Central Connecticut State University, New Britain, CT. April 17, 2010. pg. 5. 10. Boyle, J. 2010.
- Characterization of Solar Radiation Energy Input to Long Island Sound: With Application Toward Understanding the Variability in the Severity of Hypoxia. Program and Abstracts, Tenth Biennial Long Island Sound Research Conference, University of Connecticut, Stamford, CT. October 29-30, 2010. pg. 5. 11. Stevens, J., Tait, J., Peperni, N., Thomas, K., and Nixon, C. 2010.
- Estimating Sediment Metal Concentrations in Norwalk Harbor Using Sediment Mean Grain Size and Loss on Ignition Data. Program and Abstracts, Tenth Biennial Long Island Sound Research Conference, University of Connecticut, Stamford, CT. October 29-30, 2010. 12. Geist, G.N., Oshana, D., Sunila, I. and Breslin, V.T. 2010.
- Pathological Changes, Disease, and Tissue Metals in Eastern Oysters from Five Sites Along the Connecticut Coast. Program and Abstracts, Tenth Biennial Long Island Sound Research Conference, University of Connecticut, Stamford, CT. October 29-30, 2010. 13. Krisak, M. and Grace S. 2010.
- Potential Effects of Phytoplankton Abundance and Diversity on the Eastern oyster, Crassostrea virginica, in Long Island Sound. Program and Abstracts, Tenth Biennial Long Island Sound Research Conference, University of Connecticut, Stamford, CT. October 29-30, 2010. 14. Boyle, J.P. 2010.
- Characterization of Solar Radiation Energy Input to Long Island Sound: With Application Toward Understanding the Variability in the Severity of Hypoxia. 13th Annual Connecticut State University Faculty Research Conference, Central Connecticut State University, New Britain, CT. April 17, 2010. 15. Church, V. 2009.
- A Comparative Study of Sediment Metal Clinton and Milford Harbors, CT. Honors Thesis, Southern Connecticut State University, New Haven, CT. May 2009. 55 pp. 16. Church, V.M.E. and V.T. Breslin. 2009.
- A Comparison Study of Sediment Metal Contamination in Clinton and Milford Harbors. 12th Annual Connecticut State University Faculty Research Conference, Southern Connecticut State University, Adanti Student Center, April 4th, 2009.
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Progress 09/01/08 to 08/31/09
Outputs
OUTPUTS: A primary objective of this research is to assess the extent and quality of current oyster habitat (particular emphasis on New Haven and Norwalk harbors, public and private leased beds) and to identify new (underutilized) areas along the CT coast that may also provide suitable oyster habitat. Fourteen field study locations were established in Norwalk harbor (2 sites), Bridgeport harbor (1 site), the lower Housatonic River (3 sites), New Haven harbor (5 sites), Westbrook harbor (2 sites) and New London harbor (1 site). Sediment grain-size, loss-on-ignition, and metals were determined on samples were collected at each site. Temperature, salinity and turbidity measurements were made at each site during each site visit. At five of the sites, plankton tows have been completed at three month intervals corresponding with our retrieval of the temperature loggers. Plankton samples are being examined for identification purposes. Water samples and oyster tissues were sampled monthly from all habitat-study locations and analyzed for fecal coliforms from late spring-late fall 2009. Surface water dissolved oxygen, temperature and salinity, in situ surface water samples for fecal coliforms and E. coli and oyster tissue samples for fecal coliforms were determined during each sampling event. Synoptic assessment of the physical condition of existing and potential oyster beds was conducted using side-scanning sonar and sampling via ponar grab. Three locations were examined for extensive sediment characterization and benthic habitat study: Norwalk harbor, Bridgeport harbor and the Housatonic River estuary, and New Haven harbor with adjacent Long Island Sound waters. Basic elements of this work included sediment sampling via ponar grab, loss-on ignition tests to estimate organic content, grain size analysis of sediment samples using laser diffraction techniques, mapping of grain size spatial distributions in GIS and mapping LOI results in GIS. A second objective seeks to determine tissue metal concentrations and tissue pathologies for oysters located in four different watersheds along the Connecticut coastline. Oysters (20-30) were sampled on two occasions: June 2008 and November 2008. Twelve oyster tissues from each location at each sampling time were acid digested and analyzed for copper, zinc and iron. These analyses have been completed and statistical analyses of the data are underway. Thirty oysters from five sites sampled in November 2008 were also examined for pathologies. Pathologies examined included infectious agents and pathologic condition. These analyses have been completed and statistical analyses of the data are underway. We continued to conduct high spatial resolution sampling of harbor sediments to provide detailed maps of sediment metal contamination in coastal harbors. Sediment samples were collected using a ponar grab from multiple locations from throughout each of the following harbors: Norwalk harbor, New Haven harbor, Clinton harbor, Milford harbor, and New London/Thames River in support of this goal. Sediment metals and loss-on-ignition were measured and the data sets are being used to construct GIS maps. PARTICIPANTS: Principal Investigators (PI/PDs): Dr. Vincent T. Breslin (SCSU) has coordinated the overall project management and the oyster tissue metals and oyster pathology studies. Dr. James Tait (SCSU) has coordinated sediment grain-size sampling and analyses and also the side-scan sonar studies along with Dr. Suzanne O'Connell (Wesleyan University). Dr. Dwight Smith (SCSU), in association with Mr. Joseph Schnierlein (Maritime Aquarium at Norwalk), is developing educational outreach activities. Drs. Clayton Penniman and Jerry Jarrett (CCSU) are conducting the microbiological studies and oyster larvae viability studies at low levels of dissolved oxygen. Dr. Sean Grace (SCSU) has coordinated the phytoplankton characterization studies. Dr. James Boyle (WCSU) has made measurements to characterize surface energy budgets in the Norwalk Harbor region. Graduate Students: Neil Geist (oyster pathology), Melissa Krisak (phytoplankton studies), Michelle Masse-Allen (educational outreach), and Jennifer Gunther (microbiological studies). Undergraduate Students: Karen Thomas (oyster tissue metals) and Jebediah Stevens (sediment grain size analyses). Partner Organizations: Wesleyan University, Sound School Regional Vocational Aquaculture Center, New Haven, CT, Maritime Aquarium at Norwalk, Norwalk, CT TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
The research to date has focused on establishing field sites encompassing commercial and public oyster beds in conditional and approved areas along the Connecticut shoreline. Extensive field sampling of these sites and laboratory analyses have been conducted on samples collected during the reporting period in support of the study objectives. However, analyses of the field and laboratory data is preliminary and has not yet resulted in substantive outcomes.
Publications
- No publications reported this period
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