Hudson-Raritan Estuary Research Articles

The underappreciated role of biotic factors in controlling the bloom ecology of potentially harmful microalgae in the Hudson-Raritan Bay

Despite widespread distribution of harmful algal blooms (HABs) and new and improved methods for detecting and quantifying them, no unifying ecological explanation has been found. Improved understanding depends upon local, ecological studies that include analysis of phytoplankton species data in relation to both abiotic and biotic parameters. Ecological network analysis was used to detect co-occurrence patterns among abiotic and biotic parameters in a long-term monitoring dataset (i.e., 2010–2021) from the eutrophic Hudson-Raritan Estuary (HRE) between the states of New York and New Jersey. The regular co-occurrence of potentially harmful bloom-forming species with companion species observed through microscopy was supported by the results of ecological network analysis, which showed that there were far more associations between HAB species and biotic parameters (∼95%) than abiotic parameters (∼5%). Temperature was the environmental variable that was most associated with HAB species throughout the estuary. The numerous network associations of HAB species with one another and with diatoms, dinoflagellates, and zooplankton highlight the complexity of planktonic food webs and interactions. Results also suggest that some taxa may play a central role in structuring the HRE plankton communities. These findings demonstrate that biotic associations play an underappreciated role in plankton structure and the value of examining the ecology of HAB species within the breadth of their biological communities. While network analysis does not fully explain and confirm complex associations among species, it does provide fresh insights and testable hypotheses to strengthen understanding and improve prediction.

Potential sea-level rise effects on the hydrodynamics and transport processes in Hudson–Raritan Estuary, NY–NJ

Potential sea-level rise effects on the hydrodynamics and transport processes in Hudson–Raritan Estuary, NY–NJ

Pervasive occurrence of microplastics in Hudson-Raritan estuary zooplankton

Microplastics (MP) are considered emerging contaminants in the water environment, and there is an interest in understanding their entry into the food web. As a growing body of literature demonstrates the ingestion of MP by zooplankton in controlled laboratory studies, few data are available demonstrating in situ observations of MP in zooplankton. A field survey was performed to collect zooplankton in the highly urbanized Hudson-Raritan estuary. Following washing, sorting by species, and enumeration, three dominant species of copepods (Acartia tonsa, Paracalanus crassirostris and Centropages typicus) were digested. MP were filter concentrated and characterized by size, morphology, and color via microscopy and polymer type by micro-FTIR imaging and/or Raman spectroscopy. MP were observed in all extracts performed on the three copepod species with averages ranging from 0.30 to 0.82 MP individual−1. Polyethylene and polypropylene were the dominant polymer types observed and fragments and beads the most commonly observed morphologies for MP. These data were used to estimate the flux of MP through zooplankton based on gut turnover times, which we compare to estimates of MP entering this environment though the local waterways. The estimated fluxes were sufficiently large, indicating that ingestion by zooplankton is a major sink of MP in the size range subject to zooplankton feeding in surface estuarine waters.

Temporal and spatial variations of water quality in the Newark Bay Estuary

Long-term (summer 2015–2018 and short-term (summer 2018) water quality monitoring was performed to understand spatial and temporal variations of surface water quality in the Newark Bay Estuary, as well as the Upper New York Bay, parts of the Hudson-Raritan Estuary in the New York–New Jersey metropolitan area. Electrical conductivity (EC), pH, temperature, and dissolved oxygen (DO) were measured in the field, while dissolved nitrate, phosphate, and ammonia concentrations were determined in the laboratory. Long-term and short-term water quality monitoring data consistently indicated that nutrients are significantly elevated in the Hackensack River most likely due to sewage effluent from a major sewage treatment plant. Dissolved oxygen levels were sufficiently high in most parts of the estuaries, whereas the Hackensack River showed a sign of hypoxia. Nutrients in the estuaries showed significant temporal variations typically by 2 to 3-fold during the 1-month short-term monitoring period, and were correlated with EC, DO or pH. The effects of combined sewer overflows (CSOs) during wet weather on the water quality of Newark Bay appeared uncertain except for ammonia, but long-term effects of CSOs need to be further investigated because nutrients from CSOs can accumulate in bottom sediments and be remobilized. Frequent water quality monitoring is necessary to better understand the impact of human activities on temporal variations of nutrients in urban estuaries and to efficiently protect coastal ecosystems.

Restoring oysters to urban estuaries: Redefining habitat quality for eastern oyster performance near New York City.

Restoring and conserving coastal resilience faces increasing challenges under current climate change predictions. Oyster restoration, in particular, faces threats from alterations in precipitation, warming water temperatures, and urbanization of coastlines that dramatically change salinity patterns, foster the proliferation and spread disease, and disrupt habitat connectivity, respectively. New York City (NYC) coastal waters, once home to a booming oyster fishery for eastern oysters (Crassostrea virginica), are now nearly devoid of live oyster reefs. Oyster restoration in urban estuaries is motivated by the synergistic ecosystem benefits this native keystone species can deliver. Recent surveys have documented substantial remnant populations of adult oysters in the upper low salinity zone of the Hudson/Raritan Estuary (HRE) near Tarrytown, NY. This study assessed fitness-related performance across the HRE salinity gradient to evaluate habitat suitability on an estuarine scale. Oysters were hatchery-produced from wild, moderate-salinity broodstock, then outplanted for measurement of growth, survival, reproduction and disease prevalence over two years. Survival was generally higher in the lower salinity river sites and in the higher salinity Jamaica Bay sites relative to mesohaline NYC harbor sites. Growth rate was highest in Jamaica Bay and had high variation among other sites. Surprisingly, the highest proportion of individuals with sex-differentiated gametes and the highest average gonad maturation index was found at a low salinity site. Consistent with the advanced gametogenesis measured in experimental animals at low salinity, annual wild recruitment was documented near the low salinity remnant population in each of five monitored years. These results suggest that the remnant HRE oyster population is a robust, self-sustaining population that can be leveraged to support restoration of subpopulations in other parts of the estuary, but further research is required to determine if the mesohaline and near-ocean reaches of the HRE can support the full oyster life cycle.

Troubled waters: Risk perception and the case of oyster restoration in the closed waters of the Hudson-Raritan Estuary

Pathways to recognizing shared interests in addressing environmental problems are sometimes blocked by a lack of understanding or even misperceptions among stakeholder groups, which can impede productive communication. Drawing on a currently evolving case study, this study examines the perceptions of stakeholders involved with oyster restoration in waters of the Hudson-Raritan Estuary considered unsuitable for commercial harvesting (i.e., closed waters) in New York and New Jersey. Survey research conducted with commercial shellfish farmers and oyster restoration volunteers shows that support for oyster restoration is less related to stakeholder group identification and more to the perceived risks to public health and the economy, and the perceived ecological benefits. The conclusions suggest how these results might be used to demonstrate where agreement exists among stakeholder groups, which could improve discussion about oyster restoration and advance shared interests.

Social-ecological system responses to Hurricane Sandy in the Hudson-Raritan Estuary.

The impact of Hurricane Sandy on the Hudson-Raritan estuary (HRE) provided a valuable case study for exploring interactions between long-term environmental degradation, new climatic disturbance stressors, and human behavioral responses. We extend previous research on the ecological effects of major storms to compare water quality and biological parameters threeyears before and threeyears after Hurricane Sandy and consider how ecosystem shifts relate to anglers' perceptions. Results indicate that water clarity and nutrients returned to pre-storm conditions in about oneyear, while shifts in the biological community, including a significant increase in harmful algal species and declines in zooplankton and Atlantic menhaden, persisted for multiple years, and anglers continued to fish amidst ecosystem decline. Biotic recovery time in the HRE was longer than reports for other shallow estuaries frequently disturbed by hurricanes. Ecological and social responses suggest that the post-storm regime shifts and continued fishing pressure could further environmental degradation.

Clean Water Act Section 404 and Coastal Marsh Sustainability

The “no net wetland loss” goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U.S. Army Corps of Engineers and U. S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The `no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh `replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.

Immunological and reproductive health assessment in herring gulls and black‐crowned night herons in the Hudson–Raritan Estuary

Previous studies have shown inexplicable declines in breeding waterbirds within western New York/New Jersey Harbor between 1996 and 2002 and elevated polychlorinated dibenzo-p-dioxins and polychlorinated biphenyls (PCBs) in double-crested cormorant (Phalacrocorax auritus) eggs. The present study assessed associations between immune function, prefledgling survival, and selected organochlorine compounds and metals in herring gulls (Larus argentatus) and black-crowned night herons (Nycticorax nycticorax) in lower New York Harbor during 2003. In pipping gull embryos, lymphoid cells were counted in the thymus and bursa of Fabricius (sites of T and B lymphocyte maturation, respectively). The phytohemagglutinin (PHA) skin response assessed T cell function in gull and heron chicks. Lymphocyte proliferation was measured in vitro in adult and prefledgling gulls. Reference data came from the Great Lakes and Bay of Fundy. Survival of prefledgling gulls was poor, with only 0.68 and 0.5 chicks per nest surviving to three and four weeks after hatch, respectively. Developing lymphoid cells were reduced 51% in the thymus and 42% in the bursa of gull embryos from New York Harbor. In vitro lymphocyte assays demonstrated reduced spontaneous proliferation, reduced T cell mitogen-induced proliferation, and increased B cell mitogen-induced proliferation in gull chicks from New York Harbor. The PHA skin response was suppressed 70 to 80% in gull and heron chicks. Strong negative correlations (r = -0.95 to -0.98) between the PHA response and dioxins and PCBs in gull livers was strong evidence suggesting that these chemicals contribute significantly to immunosuppression in New York Harbor waterbirds.

Research Article: Eastern Oysters (Crassostrea virginica) in the Hudson-Raritan Estuary: Restoration Research and Shellfishery Policy

relief caused by winter storm energies. The research ended abruptly on August 9, 2010, when New Jersey’s Department of Environmental Protection rescinded the project permit because of concerns that research oysters were beginning to reach New Jersey’s market size of 2.5 inches. Although initial data suggest that oysters can survive and reproduce in Raritan Bay and the potential exists to achieve oyster restoration goals included in the CRP, the project also highlights the current lack of agreement between shellfishery regulators and restoration practitioners with respect to oyster reintroduction in waters where shellfish harvesting is currently prohibited. Different shellfish management approaches are used in New England states (Massachusetts, Rhode Island, and Connecticut), where local control is an important management tool, and in Chesapeake Bay states (Maryland and Virginia), where federal involvement is relatively high. Situated between these two distinct shellfish-producing regions, New Jersey and New York have not supported aggressive reestablishment of historic Eastern Oyster populations in the HRE, and unlike adjacent states, have not developed long-term oyster aquaculture plans. The reluctance to support oyster restoration is due to concerns related to human health and ecological

High-resolution shallow geophysics and geology in the Hudson-Raritan Estuary Ecosystem Restoration, New Jersey

The Hudson-Raritan Estuary of New York and New Jersey is one of the largest estuaries on the East Coast of the United States. It includes part of the New York City metropolitan area and includes the Port of New York and New Jersey. The estuary is an important economic, environmental, and recreational resource and asset for the region. Fresh water enters the estuary from the Hudson, Hackensack, Passaic, and Raritan rivers. Since the 17th century, the estuary has experienced industrialization and residential growth that have profoundly altered the estuary and surrounding land from its precolonial state.

Chemical contamination assessment of the Hudson–Raritan Estuary as a result of the attacks on the World Trade Center: Analysis of trace elements

The attack on the World Trade Center (WTC) resulted in the destruction of buildings, and the release of tons of dust and debris into the environment. As part of the effort to characterize the environmental impact of the WTC collapse, Mussel Watch Program trace element measurements from the Hudson–Raritan Estuary (HRE) were assessed for the years before (1986–2001) and after (2001–2005) the attack. Trace element measurements in the HRE were significantly higher than Mussel Watch measurements taken elsewhere in the Nation. Post-attack trace element measurements were not significantly different from pre-attack measurements. The impacts of WTC collapse may have been obscured by high ambient levels of trace elements in the HRE.

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.

Hudson-Raritan Estuary Ecosystem Restoration Project: Implementation of Representative Restoration Sites and Estuary-wide Studies.

Hudson-Raritan Estuary Ecosystem Restoration Project: Implementation of Representative Restoration Sites and Estuary-wide Studies.The United States Army Corps of Engineers has been authorized to conduct a feasibility study for the Hudson-Raritan Estuary Ecosystem Restoration Project. This project extends over the majority of the estuary, and includes the Port of New York and New Jersey. Included in the project area is Lower New York Bay (to the Sandy Hook-Rockaway transect), Upper New York Bay, Newark Bay, the Hackensack and...Author(s)Robert WillSourceProceedings of the Water Environment FederationSubjectSession 21: Hudson-Raritan EstuaryDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2002ISSN1938-6478SICI1938-6478(20020101)2002:2L.2013;1-DOI10.2175/193864702785665346Volume / Issue2002 / 2Content sourceWatershed ConferenceFirst / last page(s)2013 - 2023Copyright2002Word count114

Trends in Indicators of Eutrophication in Western Long Island Sound and the Hudson-Raritan Estuary

Significant improvements in water quality have been observed for several decades throughout much of the Hudson-Raritan Estuary, primarily as a result of regional abatement of municipal and industrial discharges. These improvements include area-wide, order-of-magnitude reductions in ambient coliform concentrations and significant increases in dissolved oxygen (DO) concentrations. In contrast to these improvements, DO in bottom waters of the western Long Island Sound (WLIS) appears to have decreased in the last two decades. Although there is no consensus as to why hypoxia in WLIS may have recently become more severe, several related hypotheses have been suggested, including an increase in eutrophication, increased density stratification, and changes in wastewater loads. To determine if eutrophication has increased in WLIS, trends in several indicators of eutrophication were examined from a long-term water quality data set. Since the mid-1980s surface DO supersaturation has increased, bottom minimum DO has decreased, and vertical DO stratification has increased in WLIS. Other areas of the Hudson-Raritan Estuary, such as Jamaica Bay and Raritan Bay, exhibit similar evidence of declining water quality and may be experiencing increasing eutrophication. Temporal changes in vertical density stratification indicate that surface to bottom temperature differences have increased to a greater extent and have had a more significant impact on bottom DO depletion in WLIS than in the shallower Jamaica Bay and Raritan Bay. Additional factors contributing to the observed decline in water quality include recent changes in wastewater loads and possible increases in upstream and nonpoint source loads.

Comparative bioaccumulation of chlorinated hydrocarbons from sediment by two infaunal invertebrates.

Bioaccumulation of chlorinated hydrocarbons (CHs) from field-contaminated sediments by two infaunal invertebrates, Rhepoxynius abronius (a non-deposit feeding amphipod) and Armandia brevis (a nonselective, deposit-feeding polychaete), was examined and species responses were compared. Sediments were selected over a large geographical area of the Hudson-Raritan estuary to assess the potential for bioaccumulation from a typical urban estuary. Unlike polycyclic aromatic hydrocarbons (PAHs) from these sediments, concentrations of CHs in interstitial water (IW) indicated that partition coefficients (Koc) were generally as expected, especially when based on predicted, nonsorbed, interstitial water CH concentrations (IWfree). Correlations between amphipod and polychaete tissue residues revealed that these species were responding similarly to a gradient of CH concentrations in sediment. While tissue residues and BAFloc (lipid/organic carbon normalized bioaccumulation factor) values for the trichlorobiphenyls were similar for both species, accumulation in the polychaete was three to 10 times higher for the more hydrophobic PCBs, which was attributed to differences in the route of exposure. A negative correlation between the bioaccumulation factor (BAF) and total organic carbon (TOC) was found for both species, which was expected according to equilibrium partitioning theory. Because it was assumed that the amphipod was not feeding in these tests and the polychaete was ingesting sediment, comparison of their tissue residues and bioaccumulation factors was useful for highlighting the importance of sediment ingestion, especially for short-term, nonequilibrium exposures. These results may also help elucidate the limitations associated with assessing bioaccumulation and the resultant toxic response in standard 10-day toxicity tests with similar invertebrates.

Sediment Toxicity in the Hudson-Raritan Estuary: Distribution and Correlations with Chemical Contamination

The Hudson-Raritan Estuary is one of several United States coastal areas where chemical data have suggested a potential for contaminant-related biological effects, and multiyear intensive bioeffects surveys have been conducted by the National Oceanic and Atmospheric Administration. The severity and spatial patterns in sediment toxicity were determined in an estuary-wide survey during spring 1991 using amphipods, bivalve larvae, and luminescent bacteria as test organisms. Spatial patterns in toxicity corresponded to the distributions of a number of toxic chemicals in the sediments. Areas that exhibited the greatest sediment toxicity included the upper East River, Arthur Kill, Newark Bay, and Sandy Hook Bay. The lower Hudson River adjacent to Manhattan Island, upper New York Harbor, lower New York Harbor off Staten Island, and parts of western Raritan Bay generally showed lower toxicity. Supporting chemical analyses of the sediments, including acid-volatile sulfide and simultaneously-extracted metals, suggested that metals were generally not the cause of the observed toxicity, with the possible exception of mercury. Among all contaminants analyzed, toxicity was most strongly associated with polynuclear aromatic hydrocarbons, which were substantially more concentrated in toxic samples than in nontoxic samples, and which frequently exceeded sediment quality criteria.

Concentrations of organic contaminants in Mytilus edulis from the Hudson-Raritan Estuary and Long Island Sound

In this paper, we present the findings of 2-, 3-, 4-, and 5-ring polynuclear aromatic hydrocarbons (PAH), selected polychlorinated biphenyl (PCB) congeners, the pesticide DDT and its degradation products, and the marine paint antifouling agent tributyltin (TBT), in the tissues of Mytilus edulis collected from 10 sites in the Hudson-Raritan Estuary and 10 sites in Long Island Sound. In the estuary, contaminant concentrations were highest in the Upper Bay, and systematically decreased moving south and east into the New York Bight. Near equal distributions of tetra-, penta-, and hexa-chlorinated PCBs in the Upper Bay systematically shifted to a composition dominated by more heavily chlorinated PCBs in the New York Bight. In Long Island Sound, contaminant concentrations were highest in the heavily populated southwest region of the Sound, while the lowest bivalve contaminant levels were observed near the eastern-most tip of Long Island. PAH distributions generally were reminiscent of complex mixtures of combustion products and refined fuel products. PCB congener distributions exhibited similar changes in composition as those observed in the Hudson-Raritan Estuary.

Concentrations of organic contaminants in Mytilus edulis from the Hudson-Raritan Estuary and Long Island Sound

In this paper, we present the findings of 2-, 3-, 4-, and 5-ring polynuclear aromatic hydrocarbons (PAH), selected polychlorinated biphenyl (PCB) congeners, the pesticide DDT and its degradation products, and the marine paint antifouling agent tributyltin (TBT), in the tissues of Mytilus edulis collected from 10 sites in the Hudson-Raritan Estuary and 10 sites in Long Island Sound. In the estuary, contaminant concentrations were highest in the Upper Bay, and systematically decreased moving south and east into the New York Bight. Near equal distributions of tetra-, penta-, and hexa-chlorinated PCBs in the Upper Bay systematically shifted to a composition dominated by more heavily chlorinated PCBs in the New York Bight. In Long Island Sound, contaminant concentrations were highest in the heavily populated southwest region of the Sound, while the lowest bivalve contaminant levels were observed near the eastern-most tip of Long Island. PAH distributions generally were reminiscent of complex mixtures of combustion products and refined fuel products. PCB congener distributions exhibited similar changes in composition as those observed in the Hudson-Raritan Estuary.

Growth and survival of three marine invertebrate species in sediments from the hudson-raritan estuary, New York

Sediments in the Hudson-Raritan estuary are known to contain high concentrations of anthropogenic contaminants, and marine organisms from this region exhibit numerous contaminant-related effects. To assess the pattern of sediment toxicity in depositional areas of this region, and to compare lethal and sublethal end points for different bioassay organisms, three benthic marine invertebrate species were exposed to sediments from 17 sites in the Hudson-Raritan estuary. Growth and mortality of the polychaete Armandia brevis and the sand dollar Dendraster excentricus were measured in all 17 sediments, while mortality and reburial ability of the amphipod Rhepoxinius abronius were assessed in nine sediments. Growth of polychaetes was determined by measuring the difference in weight after a 20-d exposure, whereas growth of sand dollars was assessed by measuring the difference in length and weight after a 28-d exposure. Amphipod mortality and reburial tests were conducted using the standard 10-d sediment bioassay. Significant growth reduction of polychaetes and sand dollars occurred in 11 of 17, and 3 of 17 sediments, respectively. Polychaete weight and sand dollar length correlated inversely and significantly with total sediment concentration of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and some selected elements. In contrast, significant mortality of polychaetes and amphipods occurred in 1 of 17 and 2 of 9 sediments, respectively, and impaired reburial ability of amphipods was not observed. Results of this study demonstrate that sediment contamination at depositional sites with the Hudson-Raritan estuary has potential to cause deleterious biological effects in indigenous benthic organisms. In addition, sublethal growth bioassays using polychaetes and sand dollars appear to be more sensitive in measuring the effects of sediment contamination than does the mortality-based bioassay using the amphipod Rhepoxinius abronius.