NH Sea Grant Research Projects

Over the past 20 years there has been a remarkable expansion of initiatives, activities and organizations in marine research in northern New England. All of these have developed out of perceived needs and opportunities, and all have substantive contributions to make. Sea Grant's role in this rapidly evolving, multifaceted regime is to help define primary, secondary and shared responsibilities; match private, state and federal resources; and develop joint research programs.

Because of the complex processes occurring in the marine environment, many scientific endeavors need to be approached from a systems level. Our program encourages investigation of the offshore, nearshore and estuarine systems. These natural systems are very much interrelated and the health, vitality and functioning of one is heavily dependent upon the others.

The research efforts currently supported by our program fall into four general areas: Conservation & Sustainable Utilization of Fisheries Resources, Sustainable Aquaculture, Coastal Ecosystem & Public Health, and Coastal Communities & Economics.

Polycyclic Aromatic Hydrocarbons Released from Sealcoated Pavements — An Evaluation of the Source and Fate of PAHs in Stormwater Runoff

Thomas Ballestero, UNH Environmental Research Group, Durham, NH 03824, 603.862.1405, tom.ballestero@unh.edu
Alison Watts, UNH Environmental Research Group

Recent studies suggest that coal tar-based parking lot sealcoat is contributing significant amounts of polycyclic aromatic hydrocarbons (PAHs) into nearby waterways through stormwater runoff. PAHs are considered by the US EPA to have adverse impacts on aquatic life and human health and therefore cities around the nation are reconsidering the use of these sealcoats in their local municipalities. The researchers are assessing the mass of PAHs this runoff may be adding to New Hampshire’s coastal waters. Sections of the UNH Stormwater Center parking lots will be coated with coal tar- and asphalt-based sealcoat. The runoff and vapor emissions will be compared to that of an unsealed control lot to determine which sealant contributes the highest PAH concentrations during stormwater events. The mass of PAHs released into the local environment over the course of two years will be determined by developing a mass balance. In addition, this research will allow for an evaluation of current stormwater treatment technologies to determine how effective they are at removing PAHs from parking lot runoff. Upon completion of the research, recommendations regarding the use of sealcoats will be made to the appropriate planners and regulators.

Does Sperm Limitation Take Place in Certain Areas of the American Lobster Fishery and, if so, Why?

Winsor Watson, UNH Department of Zoology, Durham, NH 03824, 603.862.1629, win@unh.edu

The egg-per-recruit fishery model is used to estimate annual recruitment of the American lobster by calculating the number of eggs a female will produce in the near future. However, this model may overestimate the total fecundity of females if there is a limitation in sperm. Through a combination of field and laboratory studies, Watson will be examining various factors that could potentially contribute to this limitation. Field sampling will occur in six widely separated sites of the northeastern U.S. lobster fishery to quantify male:female sex ratios and size differences. These parameters will be compared to the size of non-berried and berried females in various size classes carrying sperm, the percentage of berried females in each region carrying fertilized eggs, and the percentage of eggs in a clutch that are fertilized. Laboratory research will help Watson determine if small male lobsters are capable of mating with larger females and compare the amount of time female lobsters carry eggs based on whether or not they are fertilized. The results of this study will enable researchers and managers to more fully understand the population dynamics of the American lobster and will help refine predictive stock models.

Mercury Dynamics in Estuarine Sediments: Biogeochemical Controls on Bioavailability and Bioaccumulation Along a Chemical Gradient

Celia Chen, Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, 603.646.2376, celia.chen@dartmouth.edu
Aria Amirbahman, Department of Civil Engineering, University of Maine, Orono, ME 04469
Mary Voytek, U.S. Geological Survey, Reston, VA 20192

Tidal estuaries and their sediments are ideal locations for the accumulation of mercury (Hg) and production of methylmercury (MeHg). These neurotoxins are considered global contaminants capable of bioaccumulation and biomagnification in both terrestrial and marine food webs. Researchers will be studying the method of Hg and MeHg transformation and mobilization in porewaters at sites around New Hampshire’s Great Bay. They will be examining the process of Hg methylation and detoxification by using molecular analyses. The characterization of sulfate-reducing bacteria, which influences the cycling and bioavailability of Hg and MeHg in sediment porewaters, will be conducted using quantitative PCR techniques and DNA fingerprinting. Lastly, researchers will sample two primary consumers (Mytilus edulis and Littorina littorea) and two benthic omnivores (Carcinus maenus and Fundulus heteroclitus) to characterize the link between Hg methylation and mobilization in sediments to marine organisms. The results of this study will be used to help local and regional resource management organizations and private institutions make informed policy recommendations regarding Hg fate in the environment.

Impacts of in situ Treatment of Contaminated Sediments on the Benthic Communities of the Cocheco River, New Hampshire

Kevin Gardner, UNH Center for Contaminated Sediments Research, Durham, NH 03824, 603.862.4334, kevin.gardner@unh.edu
James Byers, UNH Department of Zoology

Many estuarine sediments throughout the U.S., including those in tributaries of Great Bay, contain elevated levels of toxic contaminants, including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) that can persist in the environment for extended periods of time. Remediation techniques have included dredging of the contaminated sediments and in situ capping, both of which have met with limited success. This research will focus on improving the in situ capping method by using thin (25 mm) geotextile mats containing reactive compounds such as apatite and activated carbon to sequester the metals and PAHs from the sediments. Mats will be deployed in the intertidal zone of the Cocheco River and will remain in place for approximately two years. Reactive mats, control mats without reactive compounds, and unmanipulated sediment control plots will be monitored to determine physical, chemical and benthic community changes during this time frame. Specifically, the research will focus on any changes that take place to the underlying sediments and the resident benthic community. The upper surface of the reactive mats will be examined to determine the rate of sediment deposition and biological colonization. The researchers will also determine the relationship between remediation and any changes that occur. The results of this project will be on display at Henry Law Park in Dover next to the test site and at the Seacoast Science Center to help inform the public about sediment contamination and remediation issues.

Microbial Interactions Influencing the Emergence of Pathogenic Vibrios in Oysters

Cheryl Whistler, UNH Department of Microbiology, Durham, NH 03824, 603.862.2359, cheryl.whistler@unh.edu
Vaughn Cooper, UNH Department of Microbiology

Consumption of raw or undercooked bivalve shellfish has caused an increasing number of gastroenteritis outbreaks throughout the world in recent years. These outbreaks have often been associated with pathogenic strains of Vibrio vulnificus and V. parahaemolyticus, both of which are present in the Great Bay Estuary. This research will determine how changing physical conditions in the estuarine environment and interspecies interactions of oyster polymicrobial communities influence the abundance and population structure of pathogenic Vibrio strains. To achieve this goal, the researchers will use multi-locus sequence typing to map the population genetic structure and virulence potential of these Vibrio strains and determine if recombination between the strains is occurring. In addition, they will characterize the environmental and microbiological conditions that impact the presence and persistence of both Vibrio strains. By identifying the causes that influence these interactions, public health officials and shellfish program managers will be better able to address shellfish-borne Vibrio illnesses and develop mitigation strategies.