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Tidal Exchange: Spring 2008

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Spring 2008 Issue

Public Access Event

Please save the date of Saturday July 26, 2008 to join us for City of Water Day on Governors Island, a confluence of harbor-lovers including boaters of all sizes and shapes. For more information, please visit www.waterfrontalliance.org or call Jennifer at (212) 935-9831 x 279.

“From parks to jobs to education and recreation our harbor and waterways are huge and diverse. Governors Island is the center of it all!”

Harbor Estuary News Contents

Harbor Project of the New York Academy of Sciences Completes its Mandate and Publishes a Synthesis of its Work (Click Here)
Susan Boehme, Gabriela Munoz, Marta Panero, and Charles Powers

Victories for Habitat in the Harbor Estuary
Two HEP Priority Sites Slated for Restoration (Click Here)

CARP: Accomplishments and Findings (Click Here)
Dennis Suszkowski and James Lodge — Hudson River Foundation

Examination of Below-Ground Structure and Soil Respiration Rates of Stable and Deteriorating Salt Marshes in Jamaica Bay (NY) (Click Here)
Cathleen Wigand

Blue Mussels (Mytilus edulis) (Click Here)
Adapted from a piece originally researched by Cathy Yuhas

Harbor Project of the New York Academy of Sciences Completes its Mandate and Publishes a Synthesis of its Work back to top
Susan Boehme, Gabriela Munoz, Marta Panero, and Charles Powers


The Harbor Project of the New York Academy of Sciences (NYAS) has been a unique, multi-year, consensus-based effort to identify the most effective ways of curbing ongoing pollutant loads to the NY-NJ Harbor and recommending specific actions to achieve those reductions. The Harbor Project has just completed its mandate and published its final report; a summary of the program’s actions and accomplishments and a detailed description of the process the group utilized. This report is meant to be a blueprint to help other groups address similar issues of environmental pollution.

This report, entitled “Safe Harbor: Bringing People and Science Together to Improve the New York/New Jersey Harbor,” concludes a series of publications on pollution prevention by the Harbor Project.

Five other reports were published, each focusing on a specific pollutant: mercury, cadmium, polychlorinated biphenyls (PCBs), dioxins, and polycyclic aromatic hydrocarbons (PAHs). Because these pollutants tend to be bound to particles, a sixth report on suspended solids was also produced to identify additional opportunities to curb loads to the Harbor while addressing the impacts of the particles themselves. All reports and other materials are available from the NYAS web site at www.nyas.org/harbor.

These publications have been produced by NYAS staff guided by the Harbor Consortium—a diverse group of local stakeholders—and its Chair. This project was possible thanks to the continued support of a broad base of funders, including the U.S. EPA Region 2 and Headquarters, the Port Authority, and the Abby R. Mauzé Trust.


The idea for the Harbor Project emerged as an alternative to the traditional regulatory approach of addressing pollution. In 1997, the U.S. EPA Region 2 and the Port Authority of New York & New Jersey funded, and the NYAS organized, a workshop to explore possible innovative approaches for the Harbor. The experts that participated in the meeting agreed that the time was ripe to embark on a collaborative stakeholder process, using the relatively new analytical tools of Industrial Ecology and focusing on pollution prevention at the source.1 The goal of such a process would be to generate actionable plans to achieve measurable reductions in contaminant loadings to the NY-NJ Harbor, its watershed, and its airshed. The “Industrial Ecology, Pollution Prevention and the New York–New Jersey Harbor” project (the “Harbor Project”) thus started in 1999 and the Consortium was launched in January 2000.

The Nature of the Harbor Consortium

The Harbor Consortium was a group of people with ties to the Harbor environment and a wide range of interests, perspectives and expertise. It included representatives from academia; consulting firms; industry and labor; professional, business, and trade associations; environmental, advocacy, and community organizations; and regulatory and other public agencies at the municipal, state, and federal levels.

The actual representatives from each participating institution changed with time and the consortium grew to incorporate more institutions. However, the group always worked towards the single common goal of identifying realistic strategies that would lead to environmental improvement through reductions in pollution to the Harbor while also considering the economic and political impacts of the recommendations. The group let the science lead the way in terms of identifying the key sources of ongoing pollution and then worked together to achieve consensus on the recommendations. Having a wide range of stakeholders ensured that critical issues, knowledge, and viewpoints were considered thus increasing the chances of recommendations actually being implemented.

The Process

The procedure for each contaminant was similar:

• A mass balance was conducted, based on available environmental sampling, to determine the amounts of the pollutant entering and leaving the Harbor by different media (e.g., wastewater, stormwater, air, runoff)

• A full industrial ecology analysis was carried out in parallel to identify and quantify all processes and products that involve the substance and their pathways throughout the economy and the environment. For instance, PCBs in light ballasts that are disposed in the regular trash could reach the Harbor through landfill leachate (if they end up in a landfill), air deposition (if incinerated), or stormwater runoff (if they break during transport of waste).

• Based on the results of the mass balance and industrial ecology analysis, NYAS staff identified points where intervention would be most efficient in curbing pollutant releases and crafted corresponding recommendations focusing on pollution prevention (P2) and best management practices (BMPs)

• The Consortium reviewed draft reports, identified where further analyses and research were needed, provided key data and contacts, and debated and reached consensus on final recommendations

• Once approved, a final report on each pollutant was professionally edited and printed

• Dissemination of key findings and recommendations and promotion of their implementation was accomplished through:

› Consortium members that encouraged the implementation of action plans through their own constituencies
› Involvement of key implementers from organizations that could influence the behavior of consumers (e.g., procurement agents, marketing directors, media)
› Distribution of the reports to a wide audience
› Outreach campaigns to promote industry stewardship and green consumption
› Presentations at regional, national and international conferences and seminars
› Public outreach and education to communities around the Harbor

Synergy with other Projects in the Region

The Harbor Project was in part possible because it set to work in a data-rich environment. The NY-NJ Harbor had been studied deeply by federal and state agencies as well as several universities. Most notably, the Contamination Assessment and Reduction Project (CARP) was underway as part of the Harbor & Estuary Program (HEP) “to understand the fate and transport of contaminants discharged into the entire estuary.” These studies were crucial to the Project’s ability to develop watershed-wide mass balances and to begin pinpointing primary sources of contaminants.

By capitalizing on existing information, using data in non-traditional ways and bringing a new perspective that focused on primary sources of toxics, the Harbor Project broadened the understanding of pollution issues in our region. Its body of research is expected to be highly valuable to HEP as this Program works to implement specific actions to achieve its goals for the Harbor, including the development of total maximum daily loads (TMDLs).

Outcomes and Findings

A few highlights of the Project’s findings and recommendations are provided below. Please refer to the full reports (available from www.nyas.org/harbor) for more details and technical aspects.

Mercury: This case helped bring attention to the significant impact that small quantity generators (e.g., dental offices, mercury switches in vehicles) may have collectively, even though each releases small amounts of mercury individually. In addition, mercury discharged to wastewater systems is of greater 5concern because it encounters the proper conditions to be converted into the more toxic methylmercury, which can bioaccumulate. Thus, the three major sectors discharging mercury to wastewater in our region—dental offices, hospitals and laboratories— were the focus of recommendations. These findings influenced the adoption of local rules and regulations dealing with dental amalgam and mercury switches in vehicles.

Cadmium: Most cadmium in our region is contained in nickel-cadmium (Ni-Cd) rechargeable batteries, most of which are not being recycled, and a large portion is exported to other regions when disposed as municipal solid waste (MSW). Although the use of Ni-Cd batteries is decreasing, inputs to the Harbor could increase if MSW management practices changed. The main recommendation was to ensure proper recycling of these products, especially taking advantage of existing industry-paid programs. NYC has recently passed a regulation mandating recycling of rechargeable batteries.

PCBs: Over half of all PCBs entering the Harbor are from the Hudson River Superfund site. The rest likely originates in releases from, and improper disposal of, old PCB-containing equipment still in use. In particular, 60 to 70 tons of PCBs in small capacitors in old household appliances will enter the MSW stream over the next 10 years because provisions for proper disposal by individuals are lacking. This case study draws attention to the need for comprehensive legislation. Although PCB production and commercialization were banned more than 30 years ago, their use in certain applications has continued to be allowed, in particular, items containing small amounts of PCBs. The fate of these PCBs can only be inferred from partial available information. In cases like this, thorough reporting should be required to keep track of rates of retirement of PCB-containing products and disposal practices.

Dioxins: Chlorinated dioxins and furans are a group of chemicals that have never been purposely manufactured and thus their flows cannot be tracked using trade and industrial statistics. They are byproducts of combustion and certain chemical processes. Notably, furans were an unintended impurity of PCBs; thus, addressing PCB sources has the added benefit of curbing dioxins and furans. The systems-view analysis applied to dioxins pointed to improper waste management as being directly or indirectly tied to the vast majority of dioxin emissions, from PCB fluid management to waste combustion, landfill fires, and landfill gas flaring. Several actions were recommended to tackle this overall issue that would also help curb other toxic emissions (for example, waste combustion also releases mercury, PAHs, and PCBs).

PAHs: This is also a family of more than 100 chemicals with varying toxicities and break down rates in the environment. PAHs have natural and anthropogenic sources, mostly as unintended byproducts of combustion and use of products derived from fossil fuels. This case study may be seen as the most complete one and included a fate and transport model. An interesting finding was that over 70% of all the PAH loadings to the Harbor are from sources related to transportation, including motor oil leaks, tire wear, and the use of coal tar-based sealants in driveways and parking lots (which is an emerging concern). As a result, a series of overarching recommendations were put forth to address this sector as a whole.

Looking into the Future: a Second Consortium?

The long tenure of the Harbor Consortium, its remarkable body of work, and accomplishments, point to the success of this process. After nearly a decade, the group grew and gained experience, and the process was fine-tuned. Consequently, members felt that this valuable approach should be applied to new challenges. There was much discussion and brainstorming as to what the next steps should be and a workshop was organized to explore the options for a possible “second Consortium”. The results from this April 4, 2008 workshop at the New York Academy of Sciences will be available shortly.

Sidebar: Methodology: Industrial Ecology

Industrial ecology (IE) is a relatively new, multidisciplinary field that brings physical, chemical, biological and social scientists together to develop analytical tools leading to sustainable economic development and long-term management of natural resources. Thus, IE emphasizes a comprehensive (or systems-view) approach that assesses environmental burdens over the entire life of a material, product, or service: from the extraction of raw materials to production, use, and recycling or disposal. By its very nature, IE is ideal to identify the best intervention points within an economic system to prevent pollution and was therefore chosen for the Harbor Project.

As an example, the IE approach applied to the mercury study, allowed recognizing the cumulative loadings from small quantity generators as a significant contribution to the harbor environment. Thus, the consortium identified mercury releases from dental offices as one of the most effective intervention points to keep mercury out of the Harbor. Recommendations centered on changes in practices (installing separator filter systems; properly collecting, storing and disposing of mercury) and material substitution. These pollution prevention actions were shown to be simpler and more economically advantageous than an end-of-pipe approach with wastewater treatment plants removing the mercury from their effluents.

Susan Boehme was the Director of the Harbor Project from 2001 to 2004 and is currently the Coastal Sediment Specialist at Illinois-Indiana Sea Grant and the Liaison to the U.S. EPA Great Lakes National Program Office

Gabriela Munoz was a Research Associate of the Harbor Project from 2003 to 2008 and is currently the Program Associate at the NY-NJ Harbor & Estuary Program

Marta Panero was the Harbor Project Manager from 1999 to 2004 and then the Director until 2007. She is currently the Research Scientist at NY University W. Rudin Center for Transportation Policy and Management

Charles Powers has been the Chair of the Harbor Consortium since its inception. He is a Co-Principal Investigator of the Consortium for Risk Evaluation with Stakeholder Participation (CRESP III) and the President of the Institute for Responsible Management.

Victories for Habitat in the Harbor Estuary
Two HEP Priority Sites Slated for Restoration back to top

Gerritsen Beach

Restoration activities could begin as early as spring 2009 at a salt marsh at Gerritsen Beach in Brooklyn. The US Army Corps or Engineers (US ACE) has allocated $ 3.5 million, appropriated through its Continuing Authority Program and cost-sharing funds for $ 1.5 million will be provided by the City of New York, Department of Parks. The project will restore 16 acres of tidal wetlands and coastal grassland/maritime forest. Maritime forests have been identified as ecosystem features that are particularly valuable for the estuary because of their extensive loss and subsequent scarcity. Benefits of the project include: reduced nonpoint source pollution into Gerritsen Creek, a tributary to Jamaica Bay (the restored site will filtrate and retain nutrients and pollutants in stormwater runoff) and increased biodiversity.

Old Place Creek

About $ 1.2 million has been awarded to restore Old Place Creek marsh, on the west coast of Staten Island. Funds will be provided by a Council of Federal Agencies cooperating to implement the National Estuary Restoration Act and by the NY State Department of Environmental Conservation.

The site is part of the larger Old Place Creek Wetland, and a tributary to the Arthur Kill, which provides habitats for fish and wading birds. These wetlands are part of the Harbor Herons Wildlife Complex— 2,196 acres of undeveloped land including tidal and freshwater marshes, a pond, creeks, and four islands—which was designated a state bird conservation area. Restoration will reinstate tidal flow to a 25 acre portion of former
salt marsh that is currently isolated from the creek by a berm and overrun by non-native
vegetation (phragmites).

CARP: Accomplishments and Findings back to top
Dennis Suszkowski and James Lodge — Hudson River Foundation

The Autumn 2007 edition of the Tidal Exchange contained an article describing the purpose and background of the Contamination Assessment and Reduction Project (CARP). Since the writing of that article, all of the CARP modeling reports have been released, the models themselves have been made publicly available, and the major findings of CARP were presented at a conference in lower Manhattan on November 29, 2007. This article will briefly present the major accomplishments and findings of CARP, and describe some likely uses of CARP products in reducing harbor contamination.
These conclusions were developed with guidance and comment from the following CARP participants, and the authors would like to thank and acknowledge these individuals for their dedication and hard work in making CARP a truly outstanding effort: Joel Baker (University of Washington Tacoma); Mick DeGraeve (Great Lakes Environmental Center); Scott Douglas (NJ Department of Transportation); Kevin Farley (Manhattan College); Simon Litten (NY State Department of Environmental Conservation); Robin Miller (HydroQual, Inc.); and Joel Pecchioli (NJ Department of Environmental Protection).

Major Accomplishments

For the first time, the major sources of contaminants of concern to the NY-NJ Harbor Estuary have been successfully identified and quantified. CARP conducted an extensive field and laboratory program, producing an enormous set of baseline data characterizing levels of contaminants in sediment, water, biota and wastewaters (sewage treatment plant effluents, stormwater and combined sewer overflows) throughout the estuary. In order to quantify trace concentrations of contaminants—particularly in water—that in the past were reported as non-detectable, CARP pioneered the use of new and refined sampling and analytical methods. Now, the publicly available CARP database allows easy access to more than 750,000 measurements.

To fulfill the program’s goal of predicting the concentrations of these contaminants in water, sediment, and biota in future years, HydroQual, Inc., developed and calibrated a series of numerical models. The models simulate the movement of contaminants through the estuary and predict how continuing contaminant inputs (from atmospheric deposition, sewage treatment plants, combined sewer overflows, stormwater, tributaries, runoff, in-place sediments and the ocean) will affect concentrations of contaminants in water, sediment and biota in the estuary over the next three decades. Using those simulations, CARP also developed an interactive spreadsheet (“Component Response Matrix”) to allow users to observe how specific load reduction strategies may affect contaminant levels throughout the estuary.

The new models also provide the ability to develop and test more detailed “what if” scenarios, where the consequences of specific actions can be evaluated over time. In an initial application, scenarios involving implementation of the Hudson River PCBs Superfund Site dredging and remediation of the highly contaminated sediments in the lower Passaic River were modeled over a more than three decade simulation period. This scenario evaluates the effect that “hot spot” removal will have on the suitability of future dredged sediments for placement at the Historic Area Remediation Site (HARS) throughout the Harbor.

Overall Findings

Although we have only begun to mine the wealth of information available from the CARP data and modeling efforts, the program has already provided some extremely valuable information about the functioning of the estuary and the role that contaminants play in it. The modeling and data analyses confirm that the estuary is a dynamic system where, in some cases, contaminants have been transported great distances from their sources and have dispersed throughout many of the interconnected waterways. Sediments in the Harbor, however, still contain large quantities of persistent contaminants from historic releases. These legacy sediments are a continuing source of contamination and generally play a larger role than current external loadings in controlling contaminant levels in water, sediment and aquatic organisms in the estuary.

In general, model simulations indicate that levels of contaminants in all media will continue to decline even if current loads remain constant. Burial of contaminated sediments by “cleaner” sediments and resuspension with transport to other areas are the dominant natural processes that result in the lowering of surficial sediment concentrations over time. Severe storms were not modeled, but they could be mechanisms for mobilizing deeper layers of contaminated sediments and causing elevations of contaminants in some surface sediments.

Over the next 10-20 years, legacy sediments are expected to be the dominant influence in controlling contaminant levels in all media of the estuary. Therefore, sediment remediation will likely be the most significant future method of source control.

The project’s major findings with regard to specific contaminants, like PCBs and Dioxins are provided below.


PCB contamination is widespread throughout the entire estuary. Data and modeling results show that most of the Harbor’s surficial sediments (i.e., the top ten centimeters) are exceeding the benchmark limits established to determine whether dredged sediments can be used as remediation material at the Historic Area Remediation Site (HARS) in the Atlantic Ocean. In addition, CARP data show that average concentrations of PCBs in white perch and American eel currently exceed U.S. Federal Food and Drug Administration (FDA) limits (for interstate commerce involving edible fish) at most locations sampled in the Harbor and in the mid-Hudson at Poughkeepsie.

The Upper Hudson River PCBs Superfund Site is the dominant external source of PCBs to the estuary (i.e., below the Troy dam to the ocean). It is estimated that three quarters of the PCB load currently entering the estuary originates in the Upper Hudson River. And modeling also shows that PCBs from the upper Hudson are transported throughout the estuary, including Newark Bay.

If PCB loadings continue at current levels, modeling indicates that surficial sediments in most of the Harbor are likely to remain unsuitable for HARS placement due to PCB bioaccumulation, even three decades from now. In addition, white perch and American eel will continue to exceed FDA tolerance limits in portions of the Hudson River. However, If the Hudson River PCBs Superfund dredging is accomplished upriver (and the Record of Decision’s estimated load reductions are attained) and Passaic River sediments are remediated, modeling indicates that much of the Harbor’s surficial sediments are likely to become HARS-suitable with respect to PCBs within three decades.


Dioxins are a family of 17 different compounds, including 2,3,7,8-TCDD—one of the most toxic, which is associated with former defoliant manufacture. CARP found that current external discharges of 2,3,7,8-TCDD to the Harbor are very small in relationship to the historic discharge of this compound that resulted in extremely high levels that still persist in sediments of the lower Passaic River region. Of the small current inputs, stormwater is the largest contributor, accounting for more than half of the current external load to the Harbor.
In the absence of major storms or other events that could result in the resuspension of highly contaminated buried sediments in the Passaic River, model simulations indicate that surficial sediments in Newark Bay may become HARS-suitable with respect to dioxin within three decades even without sediment remediation in the Passaic River. However, sediment remediation in the Passaic will reduce the time needed to achieve this benchmark.

Other Contaminants

In addition to PCBs and dioxin, twenty six other contaminants, measured or modeled by CARP, have been identified as potentially being in violation of state or federal (enforceable and non-enforceable) guidelines or criteria. Contaminants of greatest concern include: lead, mercury, polynuclear aromatic hydrocarbon (PAH) compounds, DDT and its metabolites, and several pesticides.

Next Steps

CARP products and results are anticipated to have widespread use in a number of programs affecting the estuary. Examples of these uses include the following:

• The U.S. Environmental Protection Agency (EPA), along with the states of New York and New Jersey, are now in the process of utilizing CARP data and modeling products to inform their determinations about which contaminants require development of Total Maximum Daily Loads (TMDLs) to meet appropriate water quality criteria.

• CARP data and models will likely be used to develop sediment remediation strategies in connection with the U.S. Army Corps of Engineers’ Hudson-Raritan Comprehensive Restoration Program and the Harbor & Estuary Program’s Regional Sediment Management strategy.

• CARP products have been used, and may be used in the future, in connection with the Lower Passaic River Restoration Project.

• The CARP data and model projections will be used in the further development of the NJ Toxics Reduction Workplan and its implementation plan. The implementation plan will identify significant contamination problems and develop source trackdown and pollution prevention strategies that can be applied to these problems.

While CARP collected a wealth of scientific information and significantly enhanced the understanding of the fate and transport of contaminants in this region, additional scientific inquiry is required to unravel the complexities of contaminant behavior in the system, including biological effects. This is particularly important in relationship to reducing uncertainties in management decisions. It is recommended that additional research be conducted and data be collected to increase confidence in the model projections, measure progress and trends, and better understand relevant effects of contaminants. Important topics include:

• Understanding sediment transport and deposition mechanisms in Newark Bay and the Hudson River;

• Improving estimates of contaminant loading from stormwater and combined sewer overflows;

• Evaluating sampling and analytical procedures for PAHs;

• Determining how varying levels of sediment contamination affect bioaccumulation; and

• Determining the factors causing sediment-related toxicity.

For more information, please visit the CARP website at www.carpweb.org.

Dennis Suszkowski is the Science Director for the Hudson River Foundation and the co-chair of both the CARP Management Committee and the HEP Science and Technical Advisory Committee.

James Lodge is a Project Manager with the Hudson River Foundation and was the coordinator of CARP from 2002 through 2007.

Examination of Below-Ground Structure and Soil Respiration Rates of Stable and Deteriorating Salt Marshes in Jamaica Bay (NY) back to top
Cathleen Wigand

Researchers from the US EPA Atlantic Ecology Division and the National Park Service are trying to unravel how the combined impacts of human-induced eutrophication (especially the increased loadings of nitrogen) and sea level rise are causing the deterioration of many salt marshes in Jamaica Bay. Prior to the 1970s, the salt marshes of Jamaica Bay were subjected to dredging for navigation channels and filling in for development. More recently, the marshes have been affected by sea-level rise and human-caused pollution from sewage inputs. Jamaica Bay’s urban watershed includes 36,570 acres of the boroughs of Brooklyn and Queens in New York City that drain to the bay through combined sewer overflows, many storm sewers, and groundwater seepage from the Brooklyn/Queens aquifer. A number of wastewater treatment plants discharge treated effluent into the bay and are the largest source of freshwater to the bay.

Among the salt marshes of Jamaica Bay, previous research has shown that JoCo marsh, adjacent to John F. Kennedy International Airport, is relatively stable and maintaining elevation compared to most of the remaining salt marsh islands, including Black Bank marsh which appears to be deteriorating. Currently, researchers are examining and comparing soils at Black Bank marsh and the more stable JoCo marsh, both of which are part of the Gateway National Recreation Area in NY.

Soil cores collected from these two salt marshes are enclosed in plastic (PVC) tubing and taken to a hospital in Rhode Island to be analyzed by Computer-Aided Tomography (CAT) scan imaging. CAT scans use X-ray equipment to take multiple pictures of the inside of a marsh soil core and create a 3-D image of the below-ground composition of roots, peat, particulates, and shells. These images are a good measure of how healthy the marshes are: greater below-ground biomass often correlates with healthier marshes. The accumulation of peat in soils is also important for salt marshes to keep pace with sea level rise.

Researchers are also measuring soil respiration rates at the same salt marshes. Soil respiration is an indicator of community metabolism and decomposition. Thus, increased soil respiration in marshes could point to an excessive loss of the organic matter that keeps these ecosystems healthy. Results to date show that the deteriorating Black Bank marsh has higher soil respiration rates and lower belowground biomass and peat accumulation than the more stable JoCo marsh. Ongoing research will provide a clearer picture of the seeming correlation.

Dr. Cathleen Wigand is a Research Ecologist with the US EPA National Health Environmental Effects Research Laboratory, Atlantic Ecology Division in Narragansett Rhode Island. For this study she is collaborating with EPA colleague, Dr. Earl Davey and with Dr. Charles Roman of the National Park Service.

Blue Mussels (Mytilus edulis)
back to top
Adapted from a piece originally researched by Cathy Yuhas

Blue mussels are one of the unsung heroes of the benthic realm (the bottom of a body of water). They enhance hard bottom habitats through their role in connecting them with the water column and creating or supporting structural habitat complexity. By their sheer numbers, they can filter enormous volumes of water and thereby contribute to improvements in water clarity. When harvested from certified waters, they make for a tasty dinner.

Blue mussels form small to large beds in higher salinity areas of the harbor. They prefer cool water, hard substrates such as gravel and shell beds, rocks, and submerged human-made structures with good water flow. They are not as tolerant of hypoxia (oxygen deficiency) as many other estuarine molluscan bivalve species.

Blue mussels have significant water filtering capacity, which has implications for improving water clarity in the harbor. In addition, mussel beds create microhabitats for small organisms and expand the hard surface area available for colonization by other species that live on the bottom of the harbor. Clusters of adult blue mussels that break free from their original habitat—by their own weight or water dynamics—can form small satellite mussel colonies on the nearby open sandy bottom, influencing the benthic habitat and communities there. They are considered food for many species of crabs, lobsters, fish, and shore birds, including some wintering water fowl. Mytilus readily absorbs many water borne toxic chemicals and substances (in fact it is used by EPA as a water quality monitor), which can impair its health as well as make these toxicants available up the food chain. All NY shellfish lands in NYC are closed (uncertified) for shellfish harvesting. In most of the NJ side of the Harbor, shellfish harvesting is prohibited or restricted, except for a section of the Navesink River, which opens seasonally. The species is edible and harvested recreationally in some cleaner waters by divers, by hand, rakes and dredge. It is recommended to check with the NY and NJ Shellfish programs about where shellfish can be harvested.

Eggs of this species are pelagic (i.e., they float in the water column) and large numbers are produced by each adult mussel. The larvae set as spat on any hard surface and can use its foot to crawl about a substrate to find the best location to attach by strands called byssus threads. Once attached, it stays put. Food influences growth and temperatures above 25ºC can impair growth or even prevent colonies to live much longer than a year or two without annual larval recruitment. This species is an active suspension feeder at all life stages. Besides the predators mentioned above, the larvae are eaten by jellyfish and zooplankton, the spat are eaten by a number of benthic grazers, and adults are available to sea stars and larger gastropods (snails). It competes for substrate space with barnacles and oysters and high densities of the mussel may be partially self-regulating because of food resource availability.


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