A multivariate sedimentary environmental analysis of Great South Bay and South Oyster Bay, New York

A multivariate statistical strategy for classifying paleoenvironments is effective for studying modern sedimentary processes in western Great South Bay and South Oyster Bay, New York. The 13 whole phi weight percent variables were tested for redundancy with R-mode cluster analysis. The samples were partitioned statistically into five environmentally significant facies using Q-mode cluster analysis: (A)sandy gravel, (B)sandy silt, (C)silty sand, (D)slightly gravelly sand, and (E)fine sand. An ordination depicted gradational relationships among the samples and the facies. It was used to evaluate the environmental and textural parameter gradients within the sample space. Interpretations obtained in this manner and by examination of the grain-size curves suggest that these sediments were deposited by waves and currents on beaches and in wave zones (facies C and E),shoal areas (facies B),and tidal channels (facies A and D).Tidal currents, wave action, and eelgrass control the distribution of sediments within the two bays.     

Ammonium regeneration and biomass of macrozooplankton and ctenophores in Great South Bay,New York

The rate of zooplankton ammonium regeneration was measured in Great South Bay, Long Island, New York, between July 1982 and May 1984. Ammonium excretion by macrozooplankton (>200 μm) ranged from 7 μg atoms NH₄ ¹⁺?N m^?3 d^?1 in winter to 156 μg-atoms NH₄ ¹⁺?N m^?3 d^?1 in spring. Ammonium excretion by ctenophores was greater than or equivalent to that of macrozooplankton during the period of ctenophore biomass maximum in summer and fall. The temperature coefficient (Q₁₀) for NH₄ ¹⁺ excretion was 1.74 from 2.2 to 27.5°C for macrozooplankton and 1.63 between 17 and 26°C for the ctenophores. Ammonium nitrogen excretion by macrozooplankton and ctenophores combined, accounted for 1 to 3% of phytoplankton nitrogen requirements in summer when primary productivity was high and 39% in the spring. *** DIRECT SUPPORT *** A01BY040 00005     

Sources and history of heavy metal contamination and sediment deposition in Tivoli South Bay, Hudson River, New York

Persistent inorganic constitutents preserved in sediments of aquatic ecosystems record temporal variability of biogeochemical functioning and anthropogenic impacts.²¹⁰Pb and¹³⁷Cs dating techniques were used to study the past variations of heavy metals (Pb, Cu, and Zn) and accumulation rates of sediments for Tivoli South Bay, in the Hudson River National Estuarine Research Reserve ecosystem. South Bay, a tidal freshwater embayment of the Hudson, may play an important role in the sediment dynamics of this important river. The measured sedimentation rate range of 0.59 to 2.92 cm yr⁻¹ suggests that rapid accumulation occurred during the time period represented by the length of the cores (approximately the past 50 yr). Direct measurements of sediment exchange with the Hudson River reveal high variability in the sediment flux from one tidal cycle to the next. Net exchange does not seem to be adequate to explain sediment accumulation rates in the bay as measured by²¹⁰Pb and¹³⁷Cs. The difference may be supplied from upland streams or the Hudson River during storm events. Concentrations of the metals Pb, Cu and Zn were found to be well correlated with each other within individual cores at five of six sites tested. This suggests a common proximate source for the three metals at a specific site. The evidence is consistent with mixing in some environmental compartment before delivery to the bay. While metals self-correlate within individual cores, absolute concentrations, depth distribution patterns, and ratios of the metals to each other vary among the cores collected at different locations within the bay. Organic matter, Fe content, and particle size distribution of sediments do not account for the intercore variations in metal concentration. It is likely that cores collected from different sites may have derived metals from different sources, such as watershed streams and tidal exchange with the Hudson River.     

Sediment-derived chronologies of persistent contaminants in Jamaica Bay,New York

Chronologies of particle-associated contaminant levels were developed for Jamaica Bay, an embayment of the Atlantic Ocean on southwestern Long Island. A major potential source of contaminants to the system is wastewater discharge, which comprises most of the freshwater input to the bay. Sediment core sections were analyzed for Cs-137, Pu-239, 240, and Be-7 activities which were then used to establish net particle accumulation rates. Samples deposited from the early 1950s through the late 1980s were analyzed for metals and chlorinated hydrocarbon contaminants. Trace metals, including copper, lead, chromium, zinc, and mercury, were elevated to levels several times those of pre-industrial concentrations. These metals decreased by about 50% between the mid 1960s and the late 1980s. Chlorinated hydrocarbon concentrations, including polychlorinated biphenyls, chlordane, and dichlorodiphenyltrichloroethane-derived compounds, decreased by a factor of five to ten between the late 1960s and the late 1980s. Local improvements in wastewater treatment and national efforts to regulate the uses and releases of specific chemicals are the most likely explanation of declines in contaminant levels in these sediments.     

Spatial and temporal dynamics of dissolved trace metals, organic carbon, mineral nutrients, and phytoplankton in a coastal lagoon: Great South Bay, New York

Although marine lagoons are ubiquitous features along coastal margins, studies investigating the dynamics of metal, organic matter, and nutrient concentrations in such systems are rare. Here we present a comprehensive examination of the temporal and spatial gradients in dissolved trace metals (Ag, Cd, Cu, Mn, Pb), organic and inorganic nutrients (POC, PON, DOC, N0₃ ⁻, NH₄ ⁺, H₄SiO₄, PO₄ ⁻³, and urea), and algal biomass in a lagoon estuary, Great South Bay (GSB), New York, USA. While this estuary has experienced a series of environmental problems during recent decades (urbanization, loss of fisheries, harmful algal blooms), root causes are largely unknown, in part because levels of bioactive substances, such as trace metals, have never been measured. Sampling was undertaken within multiple estuarine, riverine, and groundwater sites during spring, summer, and fall. Trace metal tracers (e.g., Ag, Mn) and statistical analyses were used to differentiate the influences of natural and anthropogenic processes on the chemical composition of the lagoon. Our analyses revealed three clusters of biogeochemical constituents that behaved similarly in GSB: constituents under strong biological control such as POC, PON, DOC and chlorophyll,a; elements indicative of benthic remobilization processes such as Mn, Cd, and Cu; and constituents strongly influence by anthropogenic processes such as Ag, Pb, PO₄ ⁻³, NO₃ ⁻, and NH₄ ⁺. Although GSB is surrounded by a densely populated watershed (c. 1 million people), it does not appear to be significantly contaminated by trace metals compared to other urban estuaries. Levels of DOC (up to 760 μM) in GSB were well correlated with phytoplankton biomass and exceeded at least 98% of values reported in similar mid Atlantic estuaries at the same salinities. These high levels of DOC are likely to be an important source of carbon export to the coastal ocean and likely promote mixotrophic harmful algal blooms in this system.     

Structural analysis of the Mystery Bay area,New South Wales

The Ordovician sedimentary rocks of the southeastern Lachlan Fold Belt in the Mystery Bay area are folded into two approximately coaxial and subhorizontally plunging fold series: F₁ and F₂. Regional domains with internally consistent F₁ and F₂ trends are juxtaposed along strike‐slip faults. Locally developed kink bands commonly have a close spatial relationship with the domain boundaries.

A faulted domain boundary is exposed in coastal rocks at Mystery Bay between north‐northeasterly trending turbidites and northwesterly trending complexly deformed cherts and pelites of the Wagonga Beds. South of the boundary fault, F₁ and F₂ trends in the turbidite succession exhibit a segmented 75° counterclockwise rotation about a near‐vertical axis within a 750 m wide zone parallel with the coast, relative to regional trends preserved farther south. The rotation zone hosts prolific subvertical kink bands and crenulations. The turbidite succession youngs towards the east and hence its present position is incompatible with its projected along‐strike position on the western limb of a major anticline exposing the older Wagonga Beds.

At least three generations of faulting are recognized. Within the coastal Wagonga Beds, a set of post‐F₁ faults is subparallel to the tectonic grain and probably had vertical motion. Two systems of post‐F₂ strike‐slip faults include a conjugate system in coastal outcrops, with offsets indicative of layer‐normal shortening; and a series of northerly trending faults, with probable sinistral displacements, recognized from inland exposures.     

Seasonal and spatial variability in macrobenthos communities in Jamaica Bay,New York—an urban estuary

Macrobenthos were sampled at 27 sites on a seasonal basis from October 1981 through November 1982. Cluster analyses and principal components analyses indicated that although spatial and species groupings were weak, an underlying sediment-correlated structure persisted for all seasons. Weak station groupings resulted from great seasonal and local variability in abundance of several dominant taxa. The most widely distributed species varied the least in density over time. Species richness (number of species) and dominance were uncorrelated. Dominance was correlated with sediment organic content [% total organic carbon (TOC)] and % Mud. Species richness increased with increasing % TOC, reaching a maximum in the range 0.7 to 1.0% TOC (primarily sand stations). At higher organic levels (muddy, sand stations), species richness declined. Muddy sand stations were dominated byAmpelisca abdita. In this community, species richness was inversely correlated both with percent TOC and heavy metals concentrations. In both sand and mud communities, species richness was positively correlated with density (mean number individuals of all species per sample).     

A nephrite deposit in the great serpentine belt of New South Wales

A nephrite jade deposit within the Great Serpentine Belt of N.S.W., near Tamworth, occurs as several tabular bodies up to 3.5 m thick on the serpentinite country‐rock contact. The occurrence is interpreted as a low‐temperature reaction zone, similar to those observed around Alpine serpentinites elsewhere. The nephrite probably formed as a result of dynamothermal metasomatism associated with the emplacement of serpentinites along the Peel Fault.     

Distribution and abundance of ichthyoplankton in the Manicouagan River estuary,a tributary of the lower St. Lawrence estuary

The species composition and relative abundance of ichthyoplankton were investigated during summer 1986 at four stations along the salinity gradient in the Manicouagan River estuary, a tributary of the lower St. Lawrence estuary. Physical characteristics of water masses indicated the presence of a strong saline front (>10‰ per km) delineating the freshwater and marine section of the Manicouagan estuary. The estuary supports a depauperate ichthyoplankton community, including four species of pelagic fish eggs and eight species of fish larvae. Species richness increased with salinity. The ichthyoplankton fauna can be divided into two distinct groups: freshwater and marine. These two groups result initially from spawning preferences exhibited by the different species abundance of freshwater larvae was maximal at the head of the estuary and marine larvae were most abundant at the most saline station. The length frequency distribution suggests that marine larvae are not effectively retained within the estuary. The Manicouagan estuary cannot be considered as a major spawning site nor an important nursery zone for any fish found in this area.     

Early Palaeozoic subduction in the southeastern Lachlan Fold Belt,Batemans Bay,New South Wales

The southeastern Lachlan Fold Belt at Batemans Bay on the New South Wales south coast is an accretionary complex with a prolonged deformation history. Early features include synsedimentary folds, mélange, disaggregated bedding and faults. Fabrics within the clast-in-matrix mélange and mudstone match those found in cores from the lower slopes of modern accretionary prisms. At the toe of the accretionary prism, the contact between the craton-derived Adaminaby Group and ocean floor deposits of the Wagonga Group is conformable. As subduction continued, the early structures were overprinted by (D₁) deformation that produced meridional north – south-trending, tight to isoclinal folds (F₁) and associated axial-plane cleavage (S₁). This west-dipping subduction occurred in the Late Ordovician/Early Silurian but probably began much earlier. A younger regional deformation (D₂) resulted in north – south-trending, open to tight folds (F₂), slightly oblique to F₁, and an axial-surface cleavage (S₂).     

Distribution and abundance of the cownose ray,Rhinoptera bonasus,in lower Chesapeake Bay

Aerial surveys were conducted in the lower Chesapeake Bay during 1986–1989 to estimate abundance and examine the distribution of the cownose ray,Rhinoptera bonasus, during its seasonal residence, May–October. Most of the survey effort was concentrated in the lower and mid-bay regions. Cownose rays appeared uniformly distributed across the bay during mid-summer, but were more abundant in the eastern portion of the bay during migration. North-south distribution varied and reflected the general seasonal migration pattern. Mean abundance increased stepwise monthly from June through September and declined dramatically in October with their emigration from the bay. Abundance estimates from individual surveys varied. The greatest range of individual survey abundance estimates occurred in September (0–3.7×10⁷ cownose rays0 due to high variation in school size and abundance between surveys. Monthly mean cownose ray abundance ranged from 0 in May and November to an estimated maximum of 9.3×10⁶ individuals in September. The magnitude of the population suggests that the cownose ray plays an important role in the trophic dynamics of the Chesapeake Bay ecosystem. The historical data were insufficient to determine whether the population has increased, but these surveys provided the baseline data which would allow future investigation of cownose ray population dynamics in lower Chesapeake Bay.     

Decadal changes in seagrass distribution and abundance in Florida Bay

The Florida Bay ecosystem has changed substantially in the past decade, and alterations in the seagrass communities have been particularly conspicuous. In 1987 large areas ofThalassia testudinum (turtlegrass) began dying rapidly in western Florida Bay. Although the rate has slowed considerably, die-off continues in many parts of the bay. Since 1991, seagrasses in Florida Bay have been subjected to decreased light availability due to widespread, persistent microalgal blooms and resuspended sediments. In light of these recent impacts, we determined the current status of Florida Bay seagrass communities. During the summer of 1994, seagrass species composition, shoot density, shoot morphometrics, and standing crop were measured at 107 stations. Seagrasses had been quantified at these same stations 10 yr earlier by Zieman et al. (1989).T. testudinum was the most widespread and abundant seagrass species in Florida Bay in both 1984 and 1994, and turtlegrass distribution changed little over the decade. On a baywide basis,T. testudinum density and biomass declined significantly between surveys; mean short-shoot density ofT. testudinum dropped by 22% and standing crop by 28% over the decade.T. testudinum decline was not homogeneous throughout Florida Bay; largest reductions in shoot density and biomass were located principally in the central and western bay. Percent loss ofT. testudinum standing crop in western Florida Bay in 1994 was considerably greater at the stations with the highest levels of standing crop in 1984 (126–215 g dry wt m⁻²) than at the stations with lower levels of biomass. While turtlegrass distribution remained consistent over time, both the distribution and abundance of two other seagrasses,Halodule wrightii andSyringodium filiforme, declined substantially between 1984 and 1994. Baywide,H. wrightii shoot density and standing crop declined by 92%, andS. filiforme density and standing crop declined by 93% and 88%, respectively, between surveys. Patterns of seagrass loss in Florida Bay between 1984 and 1994 suggest die-off and chronic light reductions were the most likely causes for decline. If die-off and persistent water-column turbidity continue in Florida Bay, the long-term future of seagrasses in the bay is uncertain.     

Distribution and abundance of overwintering blue crabs,Callinectes sapidus,in the lower Chesapeake Bay

A study was conducted to define winter distribution patterns of blue crabs,Callinectes sapidus, in the lower Chesapeake Bay and to relate these patterns to environmental variation. During February 1986 a stratified random survey was conducted to examine the distribution of blue crabs with respect to three major habitat types: 1) high energy, wave- and tide-dominated, spits and shoals; 2) moderate energy, tide-dominated basins; and 3) variable energy, tide-dominated or quiescent channels (natural or cut). Each major habitat type was further stratified on the basis of location (to account for possible salinity effects), resulting in a total of 17 habitat-stratum combinations. Blue crabs exhibited significant differences in abundance among habitats. Crabs were most abundant in the basin habitat and least abundant in the shoal and spit habitat. A posteriori evaluations of abundance patterns in relation to sediment type and depth showed that crabs were significantly more abundant where sediments contained between 41 and 60% sand and at depths exceeding 9 m. The sampled population of blue crabs was dominated by mature females. There were no significant differences in crab sex ratios between habitats, but significant differences between two fixed sites sampled through the winter showed that there were proportionately more male crabs at the western site than there were at the eastern site. The observed patterns indicate that some differential habitat utilization occurs and that overwintering female crabs are found preferentially in areas characterized by moderate energy regimes and fine, but sandy sediments.     

Tectonic stresses South Bay Mine,Canada

The South Bay copper-zinc-silver orebody, 52 miles east of Red Lake in northwestern Ontario, lies in refolded siliceous volcanic rocks near the close of an Archaean volcanic cycle. The rock mass mechanics events at South Bay mainly happened during the endogenesis and uplift of the earth's crust at the Birch-Uchi greenstone belt. After the uplift the geological history of this region was of little significance for the structure of the ore-body. The paleographic properties of the mineral deposits have been deformed by two phases of geological events; namely, first, Rotational Stress — confined pressure (geometry of torsion structures) and, second, Spherical Stress — compressive pressure (geometry of ellipsoidic structures). And, finally the structure formation in the rock mass induced natural stresses which have components determined by the geometry of the deformations.

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Zusammenfassung Das South-Bay Kupfer-Zink Lager, 80 km östlich des Red Lake im Nordwesten von Ontario gelegen, ist in gefalteten archaischen Vulkaniten von hohem Silikatgehalt eingebettet. Die gesteinsverformenden Bewegungen der South-Bay Region erfolgten hauptsächlich während der Endogenetik und der Anhebung der Erdkruste der Birch-Uchi Greenstone Zone. Nach dieser Anhebung haben die geologischen Ereignisse dieser Region die Struktur des Erzlagers kaum mehr beeinflußt. Die Petrogefüge des Minerallagers zeigen Deformationen während zweier tektonischer Phasen: zuerst freie Verdrehungsspannungen, die Torsionsstrukturen verursachten, gefolgt von allseitigem Druck, der dem Erzlager ellipsoidähnliche Strukturen aufprägte. In den Gesteinen existieren Spannungen, deren Komponenten durch die Geometry der Verformungen bestimmt sind.

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Résumé La mine de Cuivre-Zinc-Argent de South-Bay, située à 80 km à l'est de Red-Lake dans le nort-ouest de l'Ontario, se trouve dans des volcanites, à haute teneur en silicates, plissées au cours de l'Archéen. Les mouvements déformatifs dans la région de South-Bay eurent lieu principalement durant l'endogénese et le soulèvement de la cróute terrestre, le long de la ceinture de roches vertes de Birch-Uchi. Aprèsce soulèvement, les manifestations géologiques dans cette région n'eurent guère d'influence sur la structure du gisement. Les textures pétrographiques du gisement montrent des déformations se rapportant à deux phases tectoniques: d'abord, une rotation engendrant des structures de torsion, et ensuite une compression qui imprima une structure ellipsoÏdale. Il a existé dans la masse rocheuse des tensions dont les composantes ont été déterminées par la géométrie des déformations.

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Upper Ordovician graptolites from the Wagonga Beds near Batemans Bay,New South Wales

Two graptolite faunas are described from outcrops of the Wagonga Beds near Batemans Bay on the south coast of N.S.W. They are of late Eastonian and early Bolindian age. The faunas have been found in two geographically separate localities and, in spite of structural complexities, it is now suggested that the greater part of the Wagonga Beds was deposited in the Late Ordovician. The chert and volcanicrich Wagonga Beds were accumulated prior to, or as contemporaneous lateral facies equivalents of, the thick undifferentiated Upper Ordovician ‘slates and grey‐wackes unit’ that crops out in the same general region.     

Forecasting the abundance of the sea nettle,Chrysaora quinquecirrha,in the Chesapeake Bay

The sea nettle shows variable seasonal infestation in the Chesapeake Bay. Public interest in the medusal population prompted an examination of the effect of climatic, hydrographic, and biological variables on such changes. Visual medusal counts since 1960 were regressed in a stepwise fashion against the suite of variables, to produce an abundance model which allows a reasonable prediction of the forthcoming summer’s infestation. Streamflow in the entire Chesapeake watershed for the months of January through June and the water temperature for May were most important. Lower streamflow apparently provides a salinity regime which supports the sessile stages early in the year and allows the survival and rapid growth of ephyrae in early summer. The water temperatures in May furnishes the trigger for strobilation at a propitious time.     

Seasonal abundance and vertical distribution of crab larvae in Delaware Bay

Larvae of 15 species or genera of crabs were collected and identified during a six month (May 26 to October 28, 1978) study in the mouth of Delaware Bay. Seasonal abundance and vertical distribution of each species were investigated. Most species studied had peak abundance in July and August except forCancer irroratus andOvalipes ocellatus which showed peak occurrence in May and June, respectively. Larvae of species strongly dependent on estuarine habitats, such asUca spp.,Pinnixa chaetopterana, andP. sayana, showed a tendency to congregate in near-bottom waters where net flow of water is landward, thus favoring retention within the estuary. Larvae ofOvalipes ocellatus, Cancer irroratus, andCallinectes sapidus were more common at the surface. This vertical distribution suggests that these larvae are flushed out of the estuary. The mechanisms of recruitment and replenishment of adult populations within the estuary would therefore depend on migration of megalopa and juveniles. *** DIRECT SUPPORT *** A01BY019 00006     

Trench-slope channels from the New Zealand Jurassic: the Otekura Formation, Sandy Bay, South Otago

The Otekura Formation (Early Jurassic, Pseudaucella zone) at Sandy Bay comprises part of a 10+ km thick, regressive, forearc shelf and slope sequence, the Hokonui facies belt of the Rangitata Geosyncline. The Otekura Formation is dominantly fine grained, being mostly mudstone, silty mudstone and siltstone. The sediments are volcanogenic throughout. The upper 150 m of the formation contains two 20 m thick, channelized bodies of medium-thick bedded sandy flysch, each associated with thin bedded muddy flysch interpreted as overbank turbidites. Directional indicators within the channel sequence indicate emplacement from the south-southwest. In contrast, rare turbidites that occur below the channel sequence, within the background mudstone sediment, were emplaced from the east, i.e. at right angles to the channelized flows. The immediately overlying Omaru Formation contains more abundant macrofossils, intraclastic conglomerates, and appreciable amounts of traction-emplaced cross-bedded sand. Bioturbated calcareous siltstones with an in situ molluscan fauna follow (Boatlanding Formation), and are of shelf origin. The Omaru Formation is therefore interpreted as a shelf-slope break deposit, and the Otekura Formation as an upper slope facies. Reconnaissance studies indicate that the Otekura Formation is underlain by several kilometres of dominantly fine grained, deep water slope sediments, containing occasional sand and conglomerate filled channels similar to those here described in detail from the Otekura Formation. Such channels are inferred to form when a mass-transported sand, derived from failure higher on the slope, ploughs erosively into the sea floor. After their incision, the channels served for a short time as conduits for downslope transport of sediment, the redeposited deposits of which are found filling each channel. Both channel fills at Sandy Bay are capped by thin-bedded turbidites inferred to have overspilled from similar channels nearby on the slope.     

Eggs and early larvae of the bay anchovy,Anchoa mitchilli,and the weakfish,Cynoscion regalis,in lower Chesapeake Bay with notes on associated ichthyoplankton

The seasonal abundance and spatial distribution of eggs and early larvae of the bay anchovy,Anchoa mitchilli, and the weakfish,Cynoscion regalis, were determined from plankton collections taken during 1971–1976 in the lower Chesapeake Bay. Eggs and larvae of the bay anchovy,Anchoa mitchilli, dominated the ichthyoplankton, making up 96% of the total eggs and 88% of all larvae taken. A comparison of egg and larval densities from the lower Chesapeake Bay to existing data from other East Coast estuaries suggested that Chesapeake Bay is a major center of spawning activity for this species.Anchoa mitchilli spawning commenced in May when mean water column temperatures approached 17°C and abruptly ceased after August. Eggs and early larvae presented a continuous distribution throughout the study area during these months. Eggs and larvae of several sciaenid species, especiallyC. regalis, ranked second in numerical abundance. Larval weakfish were consistently taken in late summer of each sampling year but peak abundance and distribution was observed in August 1971. Sciaenid eggs exhibited a distinct polyhaline distribution with greatest concentrations observed at the Chesapeake Bay entrance or along the Bay eastern margin. Analysis of sciaenid egg morphometry and larval occurrence suggested spawning activity of at least four species. Additional important species represented by eggs and/or larvae in the lower Chesapeake Bay wereHypsoblennius hentzi, Gobiosoma ginsburgi, Trinectes maculatus, Symphurus plagiusa andParalichthys dentatus with the remaining species occurring infrequently.     

Liver lesions in winter flounder (Pseudopleuronectes americanus) from Jamaica Bay,New York: Indications of environmental degradation

Liver sections of winter flounder (Pseudopleuronectes americanus) collected from Jamaica Bay and Shinnecock Bay, New York, in 1989, were examined microscopically to determine the pervasiveness of liver lesions observed previously in Jamaica Bay winter flounder. Neoplastic lesions were not detected in fish from Jamaica Bay or the Shinnecock Bay reference site. Twenty-two percent of Jamaica Bay winter flounder examined (n=103) had unusual vacuolization of hepatocytes and biliary pre-ductal and ductal cells (referred to hereafter as the vacuolated cell lesion). The lesion, identical to that found in 25% of Jamaica Bay winter flounder examined in 1988, has previously been identified in fishes taken from highly polluted regions of the Atlantic coast (e.g., Boston Harbor, Massachusetts, and Black Rock Harbor, Connecticut). Prevalence of the vacuolated cell lesion in winter flounder from Jamaica Bay was significantly greater (p<0.0001) than in 102 specimens collected from Shinnecock Bay. Current scientific literature indicates vacuolated hepatocytes and cholangiocytes are chronically injured and that the extent of their deformity is consistent with the action of a hepatotoxicant. The high prevalence of vacuolated hepatocytes in Jamaica Bay winter flounder and absence of the lesion in flounder from reference sites strongly supports the hypothesis that this impairment is a manifestation of a toxic condition in at least some portions of Jamaica Bay.