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Hanauma Bay is a 101-acre bay created by the partial collapse of a volcanic cone and once supported a vibrant coral reef system. It is the most popular swimming area in the Hawaiian Islands and has been reported to have averaged between 2.8 and 3.5 million visitors a year between the 1980s and the 2010s, with visitors averaging between 3000-4000 a day and peaking around 10,000-13,000 per day. Concentrations of oxybenzone and other common UV filters were measured in subsurface water samples and in sands from the beach-shower areas in Hanauma Bay. Results demonstrate that beach showers also can be a source of sunscreen environmental contamination. Hydrodynamic modeling indicates that oxybenzone contamination within Hanauma Bay's waters could be retained between 14 and 50 h from a single release event period. Focusing on only oxybenzone, two different Hazard and Risk Assessment analyses were conducted to determine the danger of oxybenzone to Hanauma Bay's coral reef system. Results indicate that oxybenzone contamination poses a significant threat to the wildlife of Hanauma Bay. To recover Hanauma Bay's natural resources to a healthy condition and to satisfactorily conserve its coral reef and sea grass habitats, effective tourism management policies need to be implemented that mitigate the threat of sunscreen pollution., Water and beach sand samples were collected under permit and permission from both the City and County of Honolulu's Department of Parks and Recreation and State of Hawaii's Department of Land and Natural Resources. We thank the BIO2MAR platform (http://bio2mar.obs-banyuls.fr) for providing technical support and access to instrumentation. We thank Wendy Wiltse and her associates for assistance in sample collection. We also greatly appreciate and profusely thank the three anonymous reviewers who improved the quality of this manuscript.

Around the world, coral reefs are in decline. Recent interest has focussed on the impacts of global warming/climate change, but the decline started long before the influence of climate change became apparent, driven by anthropogenic factors such as sedimentation, nutrient increase, and overfishing. These continue with no real signs of abatement, as does concomitant reef damage. The Persian Gulf supports widespread coral growth, especially on the Iranian side. Responding to issues of food security, the Iranian government has proposed large-scale aquaculture (open-net fish pens) along their coastline, with an eventual production of 200,000 t/year. Nutrient discharge will be a major issue. We developed a hydrodynamic circulation model for the Persian Gulf which allows us to follow the path of dissolved material. We estimated the amount of nitrogen that would be produced by the projected farms and modelled nitrogen distribution over time, using production rates of 44kgN released/t of fish. In a model run simulating one year at full operation of the proposed number of fish farms, we estimate that most of the reefs on the Iranian side will be bathed in waters with nutrient levels higher than will allow for reef survival. We used a trigger value of 20 μg/l total N. Mangroves will also be affected. There is significant trans-border movement of nutrients, to the waters of neighbouring countries. In fact, withing a few years the entire Gulf will be affected. These planned aquaculture projects have the potential to damage the mangroves and kill every reef in the Persian Gulf in a very short period of time. There is a high probability of affecting fisheries resources in neighbouring countries-a situation to be avoided in politically volatile regions. There seem only two solutions: 1. either run the fish farms so that nutrient discharge is kept to acceptable levels, using an ironclad monitoring system, or 2. bring the operations on land by establishing recirculating aquaculture systems.

There is an enormous literature on the effects of sediments and nutrients on reefs. Until recently, there were few clear guidelines that could easily be used by management to alleviate these stresses. Recent progress in our understanding of watershed dynamics has brought us much closer to being able to manage catchments so as to minimize sediment stress. Timing is everything — onset of sediment pulses, wave setup — and resuspension is key. There now exist a toolbox of techniques, some off-the-shelf and some still experimental, that should allow estimates of sediment and nutrient stress on reefs, not only in the present, but also retroactively. There is danger that much of this excellent work will have been in vain. Recent work on reef trajectories has indicated that it will be very difficult to sustain healthy reefs for more than a few decades from the present. Other recent work has shown that widespread reef extirpation was occurring before 1960, coincident with European occupation and development of the adjacent coastlines.

Bamboo corals (Order Gorgonacea, Family Isididae) are attractive prospects for deep-sea paleoceanographic reconstruction, capturing trace elements in their calcitic skeletons that may serve as environmental proxies with subdecadal resolution over multi-century timescales. We study the reproducibility and fidelity of trace-element profiles (Ba, Mg, Sr, Mn, U, Pb) in a 420-year-old specimen of the bamboo coral Keratoisis sp. from the SE USA. Using laser-ablation ICP-MS to obtain multiple replicate profiles, we use spectral techniques to distinguish noise and irreproducible variations from fully reproducible geochemical fluctuations that are candidates for environmental signals. By quantifying variability between profiles, we assess the fidelity with which the corals potentially record environmental information. Barium is the most reproducible element in the skeleton, with large fluctuations along different growth radii reproducing to within 4%. Both Mg and Sr have very uniform levels within the coral, but display low-amplitude irreproducible variations that might represent an internal biological process. In the case of Mg, which has been proposed as a paleotemperature proxy, this irreproducibility would represent an intrinsic uncertainty of ∼±0.1 to 0.4 °C. Both Mn and Pb contain some irreproducibility superimposed upon broad reproducible profiles that may be environmental signals. Some of the irreproducible Pb fluctuations correlate with cracks and dark bands in the sample suggesting detrital or surface contamination. Uranium displays large amplitude variations which are not reproducible along different radii. This suggests that uranium cannot be used for paleoenvironmental reconstruction, and may show signs of early diagenesis – a possibility that could complicate attempts to date young Keratoisis sp. samples by U-series geochemistry. The highly reproducible Ba signal allows precise alignment of profiles and thus we can show that growth rate along one radius can vary by a factor of two relative to growth along a different radius. There is no evidence that this large variation in relative growth rate affects either the Mg or Sr incorporation. In addition, geochemical anomalies in Ba and Mg indicate that the very central axis of the specimen may represent a different mode of growth. This study suggests that Keratoisis sp. corals are imperfect recorders of geochemical information, but do contain reproducible variations which are good candidates for environmental signals.

In 2007, a study was undertaken of the long-term records of the ratios of stable isotopes of carbon (δ 13 C) and nitrogen (δ 15 N) in the skeletons of antipatharians (black corals) growing on reefs near the city of Jeddah, Saudi Arabia. Antipatharians were collected from more than 100 sites, and detailed records obtained from 31 individuals from 16 sites. Annual growth bands were identified and counted. Precision of age estimates was verified by bomb radiocarbon analyses. Some of the specimens were >70 yr old. Samples from a comparison reef, 15 km offshore in the Red Sea, showed δ 15 N values of 4‰ and δ 13 C values of about -18‰. The early years of growth of antipatharians from affected areas also showed δ 15 N values of 4‰ and δ 13 C values of about -18‰, but then in subsequent years these values changed, presumably as water quality deteriorated. Records from specimens in the harbour showed a steady increase in δ 15 N that paralleled population growth in the city — values from 2007 frequently exceeded 8.0‰. The carbon record also showed progressive change: since 1950, values of δ 13 C in affected areas gradually moved from about -18 to -17‰. We postulate that δ 15 N values track the input of sewage-dominated wastewater. By using correlations with species of algae that co-occur with antipatharians on outer- and mid-shelf reefs, we were able to build up a spa- tial and temporal picture of 60 yr of sewage input off this coastline. The advantage of the use of bioindicators is the ability to provide baseline water quality data in places where no such data exist.

Deep-sea gorgonian corals secrete a 2-part skeleton of calcite, derived from dissolved inorganic carbon at depth, and gorgonin, derived from recently fixed and exported particulate organic matter. Radiocarbon contents of the calcite and gorgonin provide direct measures of seawater radiocarbon at depth and in the overlying surface waters, respectively. Using specimens collected from Northwest Atlantic slope waters, we generated radiocarbon records for surface and upper intermediate water layers spanning the pre- and post-bomb- 14 C eras. In Labrador Slope Water (LSW), convective mixing homogenizes the pre-bomb Δ 14 C signature (− 67 ± 4‰) to at least 1000 m depth. Surface water bomb- 14 C signals were lagged and damped (peaking at ∼ + 45‰ in the early 1980s) relative to other regions of the Northwest Atlantic, and intermediate water signals were damped further. Off southwest Nova Scotia, the vertical gradient in Δ 14 C is much stronger. In surface water, pre-bomb Δ 14 C averaged − 75 ± 5‰. At 250–475 m depth, pre-bomb Δ 14 C oscillated quasi-decadally between − 80 and − 100‰, likely reflecting interannual variability in the presence of Labrador Slope Water vs. Warm Slope Water (WSW). Finally, subfossil corals reveal no systematic changes in vertical Δ 14 C gradients over the last 1200 yr.

The radiocarbon reservoir age of high latitude North Atlantic Ocean surface water is essential for linking the continental and marine climate records, and is expected to vary according to changes in North Atlantic deep water (NADW) production. Measurements from this region also provide important input and/or tests of oceanic radiocarbon using 3-D global ocean circulation models. Here, we present a surface water radiocarbon reservoir age record of the high latitude western North Atlantic for the deglacial period via the use of fossil cold-water corals growing in waters that are rapidly exchanged with nearby surface waters. The reservoir age of high latitude North Atlantic surface waters was computed from the radiocarbon age difference between our radiocarbon calibration record (http://radiocarbon.LDEO.columbia.edu) and our marine radiocarbon data. 230Th/234U/238U dates provide the absolute coral ages. Our high latitude North Atlantic Ocean reservoir age data combined with recalculated reservoir ages based on published coexisting terrestrial and marine material and Vedde ash radiocarbon dates from central and eastern North Atlantic show modern values (380±140 year, n=14) during the Bolling and Allerod warm period and a 200 year increase in reservoir age (590±130 year, n=10) during the entire Younger Dryas (YD) cold episode. The reservoir age then decreased to 270±20 year (n=2) at the Preboreal/YD transition, although the dates are too sparse for us to be confident in this estimate. We are not able to resolve the timing of the transition to increased reservoir ages from the mid-Allerod to the YD due to the relatively small change and correspondingly large uncertainty in the estimates. The atmospheric Δ14C record derived from our atmospheric radiocarbon record displays a 40 per mil increase from 12,900 to 12,650 cal years BP, coincident with the shift to high reservoir ages in the early YD cold event. Intrusion of 14C depleted Antarctic Intermediate Water (AAIW) to the high latitude North Atlantic and reduction of NADW formation are possible causes for the coincident shift to high reservoir ages in the North Atlantic surface ocean and increased atmospheric Δ14C during the beginning of the YD event.

A mixed equilibrium/kinetic steady-state numerical model of coral calcification has been developed to test whether a physicochemical calcification mechanism is able to account for recent geochemical observations, in particular correlated trace-element variations presented in a companion paper [Sinclair, D.J., 2005. Correlated trace-element ‘vital effects’ in tropical corals: a new tool for probing biomineralization chemistry. Geochim. Cosmochim. Acta 69 (13), 3265–3284]. The model simulates trace-element partitioning from a CaCO3 supersaturated extracellular calcifying fluid (ECF) which has been modified by enzymatic input of Ca2+ and removal of 2H+ by CaATPase. CO2 input is modelled as a diffusion process, while the ECF is continuously replenished by fresh seawater, which is the sole source of minor and trace-elements (TEs). Trace-element species fully equilibrate in the ECF, and selected trace-element species kinetically compete with Ca2+ or CO 3 2 − at the surface of the growing crystal. Each simulation is run to steady-state, and results are presented for a grid of CaATPase ion pumping rates and seawater replenishment rates. The dominant feature of the model output occurs when CaATPase ion pumping is high while seawater replenishment rates are low. At this point, CO2 diffusion reaches its maximum, C input becomes limiting, buffering capacity is reduced and the pH of the system rises dramatically; significantly affecting the TE composition of the skeleton. At more modest pumping rates, the model reproduces the relative amplitudes of trace-element variations and slopes of the mutually positive correlations between B, Sr and U observed by Sinclair [Sinclair, D.J., 2005. Correlated trace-element ‘vital effects’ in tropical corals: a new tool for probing biomineralization chemistry. Geochim. Cosmochim. Acta 69 (13), 3265–3284], but does not reproduce the negative correlations with Mg. The best fit between model and observation occurs when the coral simultaneously increases ion pumping and seawater replenishment rates: a strategy which allows rapid calcification while avoiding dangerously high pH variations. The model predicts that calcification occurs at only moderate pH elevations (8.3–8.4) with seasonal TE variations being explained by a shift of only 0.3 pH units. The model does not reproduce the full amplitude of diurnal pH variations observed recently. Sensitivity tests show that the model output is relatively insensitive to changes in the composition of the fluid from which the ECF is drawn (such as might occur if photosynthesis or active C transport mechanisms significantly modify the penultimate fluid source). Further research, however, is needed to establish the consequences of active transport of TEs and anions to the calcifying site.

Primnoa resedaeformis is a deep-sea gorgonian coral with a two-part skeleton of calcite and gorgonin (a fibrillar protein), potentially containing long-term records of valuable paleo-environmental information. For various reasons, both radiocarbon and U/Th dating of these corals is problematic over the last few centuries. This paper explores aspartic acid racemization dating of the gorgonin fraction in modern and fossil specimens collected from the NW Atlantic Ocean. Radiocarbon dating of the fossil specimen indicates a lifespan of 700 ± 100 years, the longest yet documented for any octocoral. Gorgonin amino acid compositions were identical in the fossil and modern specimens, indicating resistance to organic diagenesis. Similar to bone collagen, the fibrillar protein of gorgonin may impose conformational constraints on the racemization of Asp at low temperatures. The rate of racemization of aspartic acid ( d / l -Asp) was similar to previously published results from an 1800 year old anemone (Gerardia). The age equation was: age (years BP 2000 AD) = [( d / l − 0.020 (±.002))/.0011 (±.0001)]2 (r2 = 0.97, p d / l -Asp was marginally better than that for 14C dating over the most recent 50–200 years, although the dating error may be improved by inclusion of more samples over a broader time range. These results suggest that d / l -Asp dating may be useful in augmenting 14C dating in cases where 14C calibrations yield two or more intercept ages, or in screening samples for further 14C or U/Th dating.

Aliwal Shoal lies south of Durban in South Africa and has been the subject of recent bathymetric, seafloor and benthic surveys. ANOVA of the biological data revealed that the biota were uniformly distributed on the reef with the exception of encrusting sponges and algae on rock. The variations in distribution of these biota were significant and, in the case of the encrusting sponges, appeared to be related to the discharge of a wood pulp effluent. Further evidence of this was suggested by stable isotope analyses of representative organisms. The encrusting sponges were recommended as good candidates for further monitoring of the effects of the wood pulp effluent on Aliwal Shoal as the effluent pipeline has been extended.

The deep-sea gorgonian octocoral Primnoa resedaeformis is distributed throughout the Atlantic and Pacific Oceans at depths of 65-3200 m. It has a two-part skeleton of calcite and gorgonin. Towards the inside of the axial skeleton gorgonin and calcite are deposited in concentric growth rings, similar to tree rings. Colonies were collected from the Northeast Channel (northwest Atlantic Ocean, southwest of Nova Scotia, Canada) from depths of 250-475 m. Radiocarbon was measured in individual rings isolated from sections of each colony, after dissolution of calcite. Each {Delta}{sup 14}C measurement was paired with a ring age determined by three amateur ring counters. The precision of ring counts averaged better than {+-} 2 years. Accurate reconstruction of 20th century bomb-radiocarbon shows that (1) the growth rings are formed annually, (2) the gorgonin is derived from surface particulate organic matter (POM) and (3) useful environmental data are recorded in the organic endoskeletons of deep-sea octocorals. These results support the use of Primnoa resedaeformis as a long-term, high resolution monitor of surface ocean conditions, particularly in temperate and boreal environments where proxy data are lacking.

The gorgonians Plexaura spp. occur throughout the Florida Reef Tract, and lay down annual bands of a tough protein, gorgonin, in their skeletons. We analyzed stable isotopes of nitrogen (δ 15 N) and carbon (δ 13 C) from individual annual bands in skeletons of Plexaura homomalla and P. flexuosa from 10 locations on the Florida Reef Tract, producing a proxy record of nutrient inputs dat- ing from the mid-1970s to 2002. Isotope data were compared with tissue from offshore Belize reefs, and inshore reefs from Xel-Ha, Mexico (Yucatan Peninsula), collected in 2003. Based on previous nutrient work, Florida sites were classified as 'clean' (relatively low nutrient levels) and 'dirty' (ele- vated nutrient levels). Samples from clean and dirty sites had significantly different nitrogen isotope values, which were correlated with the average total nitrogen of the seawater. Dirty sites (3.9 ± 0.2‰ δ 15 N) were isotopically enriched over clean sites (2.9 ± 0.1‰) throughout the entire duration of the study. Dirty sites had an enrichment of 0.8‰ δ 15 N throughout the study period, with the greatest increase in the 10 yr from 1993 to 2002 inclusive. Clean sites showed no significant change since 1974. Levels and trends in δ 13 C showed a similar picture of high and increasing eutrophication stress. Clean sites had lower δ 13 C values, consistent with predominantly autotrophic nutrition; dirty sites had higher values, suggesting a shift to a more heterotrophic mode of feeding. The methods outlined herein suggest that long-term records of organic pollution on coral reefs may be retrieved from gorgonian skeletons.

The deep-sea gorgonian coral Primnoa spp. live in the Atlantic and Pacific Oceans at depths of 65 to 3200 m. They have an arborescent growth form with a skeletal axis composed of annual rings made from calcite and gorgonin. Lifespans may exceed several hundreds of years. It has been suggested that isotope profiles from the gorgonin fraction of the skeleton could be used to reconstruct long-term, annual-scale variations in surface productivity. We tested assumptions about the trophic level, intra- and inter-colony isotopic reproducibility, and preservation of isotopic signa- tures in a suite of modern and fossil specimens. Measurements of gorgonin δ 15 N indicate that Prim- noa spp. feed mainly on zooplankton and/or sinking particulate organic matter (POMsink), and not on suspended POM (POMsusp) or dissolved organic carbon (DOC). Gorgonin δ 13 C and δ 15 N in specimens from NE Pacific shelf waters, NW Atlantic slope waters, the Sea of Japan, and a South Pacific (South- ern Ocean sector) seamount were strongly correlated with surface apparent oxygen utilization (AOU; the best available measure of surface productivity), demonstrating coupling between skeletal iso- topic ratios and biophysical processes in surface water. Time-series isotopic profiles from different sections along the same colony, and different colonies inhabiting the same area were identical for δ 13 C, while δ 15 N profiles were less reproducible. Similarity in C:N, δ 13 C and δ 15 N between modern and fossil specimens suggest that isotopic signatures are preserved over millennial timescales. These results support the use of Primnoa spp. as historical recorders of surface water processes such as bio- logical productivity and the isotopic composition of source nutrients.

From September to November 1997, most of Indonesia was covered by a dense blanket of haze, originating from fires on Sumatra and Borneo. Specimens of Porites lobata were collected from two locations, i.e. the Riau Archipelago, south of Singapore, where the haze was most dense, and the Karimunjawa Islands, north of Central Java, where the effects were less severe. All corals exhibited strong Kinetic Isotope Effects (KIE). On plots of δ 18 O vs. δ 13 C, shifts in coral metabolism associated with the haze event could be estimated from the distance individual values are positioned from the theoretical KIE line. Skeletons of corals affected by the haze showed decreased δ 13 C values, perhaps produced by a shift to a more heterotrophic mode of feeding. These results suggest that wildfires and major forest fire events on tropical coastlines may be recorded in nearby corals, as could temporal variation in frequency of major fires. Moreover, information on coral metabolism may be determined by examining shifts of coral skeletal values in C–O space.

Hundreds of large coral reefs up to 45 m high exist (A) on the continental shelf and (B) on morainic threshold ridges in fjords of northern, mid-, and southwest Norway. They occur in water depths between 400 and 40 m, and contain a large variety of megafauna. The most common frame-building coral is Lophelia pertusa (L.). The oldest reef found to date is 8600 calendar years old, determined by radiocarbon dating of buried Lophelia skeleton. Even though many of these reefs have been known to science for over 200 years, there is as yet no viable and unifying hypothesis to explain their existence in deep, cool waters, other than perhaps the ‘hydraulic theory’, presented by the author in 1990. It states that primary producers (mainly bacteria) are locally formed and concentrated at reef locations due to seepage of light hydrocarbons (mainly methane) on the continental shelf, and nutrient-rich groundwater in the fjords. The hydraulic theory is supported by the following topographic, reflection seismic, and geochemical indicators; for the continental shelf reefs (A): seaward-dipping sedimentary permeable strata, enhanced acoustic seismic reflectors, adjacent pockmark craters, locally elevated light hydrocarbon sediment content, locally elevated seawater methane content; for the fjord reefs (B): threshold morainic substratum rather than adjacent hardrock substratum, sub-surface dipping sedimentary layers, H2S smell of near-surface sediment samples. These indicators, or reef-associated observations, have been documented by German, British, and Norwegian researchers over the last 10–15 years. However, all the listed indicators do not necessarily occur at each of the respective shelf and fjord reef locations simultaneously.

Mollusc shells of several species were deployed on racks and on the seafloor for up to two years on eutrophic and mesotrophic reefs in the Java Sea, a modern epeiric sea. Taphonomic indicators of shell preservation decreased during the study, but some ligament, periostracum, and shell color persisted throughout. Shell fragmentation was negligible except for species with easily chipped margins; weight loss was less than 5% for sturdy shells and up to 15% for shells with chipped margins. Shells deployed in mesh bags on the sediment surface had low encrustation and bioerosion, probably because of partial or complete burial. Areal encrustation on shells in bags was greater at the mesotrophic site than the eutrophic site, but animal encrustation and biovolume of encrusters was greater at the eutrophic site. Shells elevated on racks were encrusted rapidly at all sites; animal encrustation rates were correlated positively with productivity, and biovolume of encrusters was greater on nearshore eutrophic reefs than on offshore mesotrophic reefs. Bioerosion rates were variable but also tended to be higher at the more productive site. Natural shells also exhibited a positive, though less strong correlation with productivity suggesting that encrustation intensity and shell bioerosion may serve as relative indicators of productivity in the fossil record.

A subfossil fragment of the deep-sea gorgonian coral Primnoa resedaeformis was 14C AMS dated along a radial growth transect. Dates ranged from 2600±50 at the outside, to 2920±60 14C years BP near the interior, suggesting an age of

A specimen of Desmophyllum cristagalli, an azooxanthellate (non-photosynthetic) coral was intensively and systematically sampled on all interior and exterior coeval surfaces. Even though the coral grew at an almost-constant temperature of about 2.5 °C, δ18O varied by almost 3‰ and was up to 3.25‰ depleted with respect to aragonite–seawater oxygen isotope equilibrium. Contour maps of δ18O show that, although portions of the skeleton approached equilibrium, the location of those areas were unpredictable and were not associated with any readily identifiable characteristics, such as colour, texture or crystalline structure changes. The use of regression lines and intercepts will give the mean temperature experienced by individual corals (Smith et al., 2000, Palaios 15: 25), but the prospect of documenting temperature changes over the lifetime of an individual coral remains problematical. Because of the large and seemingly random degree of isotopic disequilibrium, several isotopic values from coeval skeletal material must be obtained for the determination of a single temperature. Although azooxanthellate corals have been shown to have growth banding, analogous to reef corals, the layers are thin and difficult to see with the naked eye, uneven and often discontinuous, rendering sampling for a `time series' impossible at present. Reasons for the degree of variation in the isotopic patterns remain unclear.

The deep-sea gorgonian coral Primnoa resedaeformis has an arborescent skeleton composed of both calcite and a horn-like structural protein called gorgonin. We have investigated potential climate records in corals from Alaska, the eastern seaboard of Canada and the United States, and a Southern Ocean (Pacific sector) seamount. Temperatures at these sites range from 4 to ∼10 °C. δ18O values of the calcite show strong evidence for isotopic disequilibrium. Extraction of δ18O paleotemperatures is therefore not straightforward. Sr/Ca data, analyzed by Secondary Ion Mass Spectrometry (SIMS), suggest that temperature might be a control on calcite Sr/Ca in Primnoa resedaeformis, but that growth-related kinetic effects could also be important. Based on previous 14C, δ13C and δ15N measurements, it has been suggested that particulate organic matter (POM) from the surface is an important carbon source to the polyps and the gorgonin fraction of the Primnoa skeleton. δ15N and δ13C of polyps and gorgonin show similar regional differences to δ15N and δ13C of surface POM. Polyps and contemporaneous gorgonin correlate strongly for both δ13C and δ15N. The influence of nutrient isotopic composition and climate and productivity variations on the isotopic composition of surface POM may therefore be recorded in gorgonin layers. These corals have very long lifespans (several centuries). The potential exists, therefore, to obtain extended records of surface productivity, deep ocean temperature and chemistry of value to climatologists and fisheries managers.

The Java Sea, one of the few modern tropical epeiric seas, is used as an analogue to examine oceanography, stratigraphy, and reefs of Devonian strata in the Appalachian and Michigan Basins. Nearshore patch reefs and offshore “pinnacle” reefs occur in both the Java Sea and the Emsian-Eifelian Onondaga Formation in the Appalachian Basin. Nearshore patch reefs also occur in the Eifelian Formosa Reef Limestone in the Michigan Basin.

The discovery of an unconsolidated deposit of iron ooids of a kind not previously described, and in the vicinity of a volcanic island in Indonesia has shed new light on the genesis of many ancient iron oolites. The discovery shows that iron ooid formation is geologically a rapid process. The ooids form by chemical precipitation of cryptocrystalline iron oxyhydroxides on available grains on the seafloor, from seawater enriched with Fe, Al and Si. The enrichment can be a result of hydrothermal fluids, volcanic ash falls into shallow basins or rapid weathering of fresh volcanic rocks. Ordovician iron ooids from northern Europe are strikingly similar to the modern ooids in chemical composition, REE distributions and internal structures. The differences in mineralogy can be explained as diagenetic transformation reactions under different environments. A model for the formation of the Ordovician iron ooids in northern Europe from volcaniclastic material is presented, which could be applicable to other ancient oolites in the world.

The degree of bioerosion of live massive corals and rubble from branching corals were measured on nine reefs from two regions of Indonesia: the Java Sea and Ambon. Bioerosion in massive corals was measured by collecting live corals, cutting and X-raying slabs, and measuring the cross-sectional area removed from each slab by the various bioeroding organisms. A technique analysing branching coral rubble was developed and similarly used to evaluate the degree of bioerosion on the reefs. This rubble technique has potential advantages over the massive coral technique since it does not require the expense and technical expertise of making and analysing X-rays, nor does it require the destruction of living coral heads. The effectiveness of this rubble technique is evaluated here. Levels of bioerosion in massive coral heads and rubble from branching corals are each compared with environmental variables and health parameters of the nine reefs. Overall, both techniques showed that bioerosion levels were positively correlated with environmental variables indicative of eutrophication. Bioerosion of live massive corals and of branching coral rubble were positively correlated. At the Ambon sites, where the eutrophication levels differ only slightly compared to the Java sites, bioerosion in coral rubble was a more sensitive indicator of eutrophication stress than bioerosion measured from massive coral heads. The rubble technique we outline is a useful rapid reef assessment technique that could be a valuable contribution to the `reef survey toolbox'.

The 15N content of tissue from the coral Porites lobata was enriched, relative to corals from reference sites, at 5 of 7 Indo-Pacific sewage-affected reefs. Enrichment was as high as 3.7‰. The δ13C of sewage-affected corals suggests they maintained a high degree of autotrophic nutrition. 15N-enriched wastewater dissolved inorganic nitrogen (DIN), derived from untreated sewage, is the most likely cause for enrichment in coral tissue 15N, though changes in coral nutrition, metabolism and zooxanthellae population dynamics are possible additional factors. Isotopic measurements of coral tissue can provide a simple means of detecting wastewater uptake by corals.

The coral reef in Tutum Bay, Ambitle Island, Papua New Guinea, is exposed to the vigorous discharge of hydrothermal fluids (up to 98°C). This study investigates eight Porites lobata samples that were collected throughout the area of active venting at varying distances from vent sites. A sample from a “non-hydrothermal” coral (C-29), collected 10 km north of Tutum Bay, was analyzed for comparative purposes. Density banding is moderately well developed in these corals and subannual bands are common. For corals from Tutum Bay, δ13C ranges from −4.5 to −1.0‰ and δ18O from −6.0 to −3.8‰, which are relatively depleted values for shallow water Porites. The comparison sample, C-29, has δ13C values ranging from −1.8 to −0.5‰, and δ18O values of −5.4 to −4.6‰. Concentrations of As, Co, Cr, Ga, Ge, Mo, Nb, Ni, Pb, Rb, Se, W, Y and Zr were always below their respective proton probe detection limits. Ba, Br, Cu, Fe, Mn, and Zn were detected in some samples. Sr was detected in all samples and concentrations ra...

This paper assesses variation in coral species diversity within the Indonesian archipelago, and the influence of regional species pools, geo- morphology and anthropogenic pollution on coral species diversity and occurrence. We obtained transects from 33 sites on 14 reefs in three regions of Indonesia: Ambon (Moluccas), South Sulawesi and the Java Sea. We determined the within-site species richness by using species- sampling curves. Cluster analysis and multi- dimensional scaling showed that land-based pollution was the primary determinant of coral species diversity and species occurrence on reefs. Relatively unaffected reference sites in eastern Indonesia were approximately 20% more diverse than Java Sea reference sites. Rare species formed a higher proportion of the coral fauna on east- ern Indonesian sites, and eastern Indonesian apparent endemic species contributed approx- imately 25% of the total species pool sampled. Between-site variation in species occurrence was lower on Java Sea reefs than on eastern Indonesian reefs. A larger species pool in eastern Indonesia than in the Java Sea probably accounted for most of the difference in within-site spe- cies diversity between eastern Indonesian and Java Sea reference sites. High fishing intensity in the Java Sea, including destructive fishing practices, may have also contributed to reduced within- site species diversity on Java Sea reference reefs. Despite the fact that the Java Sea was exposed during Pleistocene lowstands, and was recolon- ized by marine organisms only within the last 10 000 years, coral species diversity and assem- blage composition on the Java Sea reefs was largely similar to open ocean reefs in eastern Indonesia.

Massive coral growth rates may be poor indicators of coral reef health where coral reefs are subject to combined eutrophication and sedimentation. Massive coral growth (vertical extension) rates on polluted reefs were not different from extension rates on unpolluted reefs, while live coral cover was low and bioerosion intensity high, leading to net reef erosion and death of the polluted reefs. These combined patterns of coral growth rates, coral cover and bioerosion were documented on reefs affected by land-based pollution in the Java Sea, South Sulawesi and Ambon, Indonesia. Acid-insoluble content in coral skeletons reflected land-based pollution stress on reefs more reliably than did coral extension rates. Coral skeletal density was lower on polluted Java Sea reefs than on unpolluted reefs used as reference sites, but coral calcification rates were not significantly different. The most eutrophied Java Sea reefs had net carbonate loss, indicating net reef erosion, while a fringing reef adjacent to mangroves and two unpolluted coral cays both had positive net carbonate production. Coral growth and reef growth were decoupled, in that coral growth rates did not reliably predict rates of reef accretion. The apparently paradoxical combination of normal to rapid coral growth and net reef erosion on polluted reefs illustrates the need for a whole-reef perspective on coral reef health.

Thirty-five azooxanthellate (non-photosynthetic) corals belonging to 18 species were collected at sites ranging from the Norwegian Sea to the Antarctic and of depths ranging from 10 to 5220 m. All specimens showed distinct, well-defined linear correlations between carbonate oxygen and carbon isotopic composition, with slopes ranging from 0.23 to 0.67 (mean 0.45 ± 0.9) and linear correlation r2 values that averaged 0.89. These pronounced isotopic disequilibria have, to date, rendered azooxanthellate corals unsuitable for use in paleothermometry. Most, but not all, of the heaviest skeletal δ18O values reached or approached equilibrium. If the isotopically-heavy ends of the δ18O vs δ13C regression lines reliably approximated isotopic equilibrium with seawater, these values could be used to estimate the temperature of the water in which the coral grew. The δ13C values of the heavy ends of each line, however, were always depleted compared to carbon isotopic equilibrium with ambient bicarbonate by vary...

Coral reefs can be classified using triangular diagrams based on coral morphology; these taxonomy-independent classes predict several aspects of conservation value for coral reefs. Conservation classes (CC's) of 1, 2, 3 or 4 were assigned to reef sites dominated by massive and submassive corals (CC 1), foliose or branching non-Acropora corals (CC 2), Acropora corals (CC 3), or approximately equal mixes of these three end-members (CC 4). When applied to 15 Indonesian coral reefs, aggregrate conservation class, the average of the conservation class of all sites on that reef, was a reliable predictor of coral species richness, habitat complexity, and rare coral species occurrence. Aggregate conservation class predicted these aspects of conservation value more reliably than the reef condition index currently used in southeast Asia, live coral cover, or coral mortality. Definitions of reef status based solely on percentage of live coral cover should be supplemented with other indices such as conservation class that more accurately predict biodiversity value and fisheries potential. Coral morphology triangles and conservation class can be used in zoning marine protected areas and other coral reef biodiversity conservation efforts.

Skeletal banding has been found in the deep-water scleractinian coral Desmophyllum cristagalli, an important animal in studies of climate change. This banding pattern sheds light on skeletogenesis and suggests methods by which the record of climate change contained within the coral skeletons may be interpreted. A central wall built of trabeculae forms the interior of the septa and rings the theca. Lamellae form a sheath over the trabecular frame, showing continuity from thecal edge to septum. Skeletal bands are added by the tissue layer, which overlaps and seals the internal coral and upper portion of the outer theca. Truncated inner bands on the outer theca indicate a pattern of skeletal deposition and dissolution dependent on the presence or absence of the live tissue layer. A long-term record will be difficult to collect from D. cristagalli since lamellae are less than 10 μm thick and band position is unpredictable. Density banding in shallow-water coral skeletons has long been recognized as a valuable paleo-oceanographic tool, and deep-water corals are now being used to reconstruct deep-ocean environments. Pattern of skeletal growth must be carefully considered if deep-water corals are to be used as proxy climate recorders.

Trace-element and stable-isotope analyses were performed on azooxanthellate corals from the North Atlantic, at two different tectonic settings. One set was from Orphan Knoll, near Newfoundland (1700 m depth, 50°25.57'N, 46°22.05'W), the other from the Mid-Atlantic Ridge (1200 m depth, 45°14.12'N, 28°34.12'W). The Mid-Atlantic Ridge corals contain significantly greater quantities of Fe, Mn, Cu, Ni, and Zn within their skeletons than the Orphan Knoll corals. The metal concentrations are not homogeneous within the Mid-Atlantic Ridge coral skeletons, but occur as episodic pulses during a decade or two of each coral's lifetime. We believe these metals originated in a hydrothermal discharge zone associated with the Mid-Atlantic spreading centre. If so, it is evidence that the duration of an individual hydrothermal event is from a decade up to 30 years or so. With more specimens of known ages, it may be possible to reconstruct the history of a particular segment of an oceanic spreading centre. Resume : Les elements en traces et des isotopes stables ont ete analyses sur des coraux sans zooxanthelles de l'Atlantique Nord cueillis dans deux contextes tectoniques differents. Une serie d'echantillons provenaient d'Orphan

In this study, we investigate potential sources of nitrogen for the scleractinian coral Porites lobata in a transect across the central region of the Great Barrier Reef, Australia. The experiment followed a 1-way, Model I, nested ANOVA design. We sampled colonies of P. lobata from 12 reefs spanning the 110 km wide continental shelf at 5 m depth, and determined the δ 15 N signature in tissue extracts (with zooxanthellae; n = 46). The response curve of the δ 15 N was found to be curvilinear, yielding a highly significant parabolic relationship with distance from shore (p < 0.001, second-order least-squares polynomial regression). Highest values of δ 15 N were observed inshore (5.0 to 5,5‰), lowest values at the mid-shelf (∼3.8‰), and high values again offshore (5.2‰), We suggest the following causal factors, based on environmental characteristics and phenomena known to occur in this region: (1) inshore corals may be receiving much of their nitrogen from terrigenous sources; (2) mid-shelf corals may be receiving at least some of their nitrogen from associated algal mats known to possess high rates of nitrogen-fixation in this region, which in turn could lower δ 15 N values; and (3) offshore corals may be receiving their nitrogen from seasonal, nutrient-rich, cold-water intrusions or upwellings, documented to occur in this area.

Species-area curves calculated from line-intercept transect surveys on 15 reefs in three regions of Indonesia allow estimation of the relative decrease in within-habitat coral species diversity associated with different types of reef degradation. Reefs subject to land-based pollution (sewage, sedimentation, and/or industrial pollution) show 30–50% reduced diversity at 3 m, and 40–60% reduced diversity at 10 m depth relative to unpolluted comparison reefs in each region. Bombed or anchor damaged reefs are ca 50% less diverse in shallow water (3 m depth) than are undamaged reefs in the same region, but at 10 m depth the relative decrease is only 10%. Comparison reefs in the Java Sea are ca 20% less diverse than their counterparts in Ambon, Maluku. The results, compared with a previous survey in the Spermonde Archipelago found a 25% decrease in generic diversity of corals on two reefs resampled after 15 years. The decreased diversity on reefs subject to land-based pollution implies a dramatic, rapid decrease in Indonesian reef-based fisheries resources.

Nitrogen isotope values from coral tissue collected over depth–light gradients are reported from Jamaica and Zanzibar. The Jamaica suite consists of multiple specimens of three coral species (Montastrea annularis, Porites astreoides, and Agaricia agaricites) sampled at increasing depths. For each species, combined tissue/zooxanthellae δ15N decreases significantly with decreasing availability of photosynthetically active radiation. The Zanzibar sample suite was collected from three coral colonies (all Porites lobata). Multiple samples, occupying different depths and light regimes, were collected from each coral corallum. The Zanzibar suite shows a significant decrease in δ15N over the relatively small depth range represented by each coral colony. Together, these two sample suites suggest that light is an influence on the nitrogen isotopic composition in corals containing symbiotic zooxanthellae. We propose that in high-irradiance conditions, uptake and assimilation of dissolved inorganic nitrogen (DIN) by symbiotic algae and(or) the host strongly depletes the coral internal DIN pool, leading to reduced fractionation relative to reef DIN. In lower light conditions, less dissolved nitrogen is assimilated and fractionation increases. The autotrophic portion of the diet is thought to be sufficiently abundant in nitrogen and isotopically depleted to result in lower δ15N of host tissues under lower light conditions.

The coral Desmophyllum cristagalli from a water depth of about 1700 m from Orphan Knoll in the North Atlantic is examined with respect to bioerosion. Macroborings are represented by Entobia, produced by boring sponges. Microborings comprise four distinctive forms attributed to the work of fungi. Micrite rims are reported from deep‐water settings.

We present the first δ18O and δ13C data from mollusc aragonite from Lake Erie for the 4.6–0.2 ka (4600 BP to 200 BP 14C yrs) time interval and describe single and composite species isotope trends. Composite species δ18O data show an almost 2.0%o increase from 3.3 to 3.0 ka followed by a nearly 2.5%o decrease at 2.8 ka. Oxygen isotope values then fluctuate by < l‰ until 0.2 ka. This trend in oxygen values is also evident in single species analyses of Sphaerium striatinurn. The most dramatic changes in isotope values, which occur from 3.3–2.8 ka, may reflect a pattern of water level changes in Lake Erie which occurred during the Nipissing flood and its lower water aftermath. Carbon isotope data show progressively more 13C enriched values from 4.6 ka (averaging–6.5‰ PDB) to the present (–0.57‰). This trend may reflect the dilution of isotopically light CO2 from the oxidation of organic matter due to rising lake levels. The short-term increase in δ18O values is coupled with a corresponding decrease in δ13C values. A similar pattern for Lake Erie prior to 10.5 ka was also associated with a lowering of water levels in the lake.

Bioerosion intensity has been proposed as a measure of paleoproductivity in fossil reefs, but it is difficult to measure directly because fossil corals are often incomplete and because it is difticult to infer the length of time a given coral was exposed to bioeroding organisms. Both nutrient availability and taphonomic factors can affect bioerosion intensity as measured in dead corals. Here, we examine these two effects separately using data from previous studies on bioerosion in modern and fossil corals. Size of individual sponge borings accurately reflects total bioerosion in modern massive and branching corals on the Great Barrier Reef. Total bioerosion in both massive and branching corals decreases outward across the continental shelf, paralleling trends in nutrient availability. Size of individual Cliothosa hancocki borings decreases across the shelf in branching Acropora but not in massive Porites. Fossil sponge borings Entobia convoluta and Uniglobites glomerata in massive corals from Oligocene and Miocene reefs in Puerto Rico are smallest in Oligocene shelf-edge reefs, intermediate in Oligocene patch reefs, and largest in Miocene patch reefs. Both facies-related influence, represented by Oligocene shelf-edge reefs vs. Oligocene patch reefs, and nutrient-related influence, represented by Oligocene vs. Miocene patch reefs, were reflected in the size of sponge boreholes. Size of sponge borings also varies among species of host corals, apparently in relation to skeletal architecture. Borehole size is inversely correlated with skeletal density as measured by the relative proportion of skeleton and pore space in transverse thin section. There is a weak positive correlation between borehole size and corallite diameter. These findings contradict reported positive correlations between total bioerosion and bulk density in modern corals. Borehole size appears accurately to reflect intensity of total internal bioerosion in fossil corals. Facies-controlled taphonomic overprints and influence of skeletal differences between coral species limit the use of sponge borehole size to a rough indicator of paleoproductivity in fossil coral reef environments.

Natural tracers in bottom sediments around the outfall of the Burlington Skyway Sewage Treatment Plant (STP) were analyzed to investigate the pathways of fine contaminated sediments associated with the outfall. The properties examined were: coprostanol and isotope ratios of nitrogen and carbon. The spatial distribution pattern for all the tracers was characterized by extreme values in the vicinity of the outfall, with a systematic decrease with distance. The STP outfall is clearly the source for coprostanol as well as for light 15 N and heavy 13 C. The distribution pattern for coprostanol and δ 15 N showed the most consistent transport patterns, while δ 13 C patterns were different and might be contaminated by terrestrial carbon from sources other than the STP. Interpretation of the net transport patterns from coprostanol and δ 15 N indicates a primary transport trend southward, with a secondary trend northward, curving westward. The net transport patterns inferred from the tracer indicators are compatible with models of two-dimensional circulation of a buoyant effluent plume, under the effect of the prevailing wind-driven current regime.

The degree of internal bioerosion was examined in the dead basal portions of live branches of the scleractinian coral Acropora formosa collected from six reefs across the continental shelf in the central region of the Great Barrier Reef, Australia. The bioeroders included the sponges Cliona spp. and Cliothosa spp., the boring bivalve Lithophaga sp., and sipunculid and polychaete worms. Total internal bioerosion exhibited higher means and variances inshore and at the mid-shelf than the outer shelf specimens, which were characterized by low means and low variances. Bioerosion by Cliothosa and all sponges combined declined slightly across the shelf. Bivalves accounted for a small proportion of the internal bioerosion in A. formosa. The bioerosion pattern exhibited by worms (polychaetes and sipunculids) was similar in pattern to that of the sponges. All groups exhibited lowest levels of bioerosion at the outer shelf. Highest variance in the data was observed at the intra-branch/intra-colony and the intercolony levels. Inter-site variance was high in worms and vivalves. Boring sponges generally dominated the bioeroder community. The relative abundance of Cliona declined on the outer shelf while the relative abundance of worms increased. Percent bioerosion in Acropora formosa was 2–3 times higher than in Porites lobata in this region. The low level of bioerosion at the outer shelf versus the inner- and mid-shelf areas may be partially due to lower levels of productivity and lower concentrations of terrestrially derived organic matter. Other potential factors may include higher fish grazing/predation activity on the outer shelf.

Approximately half of the Caribbean Oligocene reef coral fauna became locally extinct during the Early Miocene; roughly two thirds of the genera driven to local extinction still survive in the Indo-Pacific. Coral genera with lecithotrophic larvae (brooders) preferentially survived, over those with planktotrophic larvae (broadcasters). Among 37 genera for which we inferred reproductive mode, 73% of brooding genera survived the Oligocene/Miocene extinction events, while only 29% of the broadcasting genera survived. The proportion of brooders to broadcasters also increased markedly. During the late Oligocene, 47% of Caribbean reef coral genera were broadcasters, but in the middle Miocene, only 32% of the genera were broadcasters.Survivorship in Puerto Rican reefs was correlated with tolerance of cold and turbid conditions. Genera tolerant of both cold water and turbidity had much higher survival rates than those tolerant of turbidity alone. Only 25% of the genera that could tolerate neither cold water nor turbidity survived. Most of the eurytopic genera were brooders, while most of the stenotypic genera were broadcasters.We present two hypotheses that may account for the preferential survivorship of brooders: the recruitment hypothesis, and the dispersal hypothesis. The recruitment hypothesis holds that brooders survive preferentially because lecithotrophic larvae have higher recruitment success than do planktotrophic larvae in marginal habitats, such as upwelling zones. This is supported by the correlation of brooding and eurytopy. The dispersal hypothesis suggests that brooders survive preferentially because lecithotrophic larvae, which typically inherit zooxanthellae from the egg, have a longer larval lifespan and, hence, a wider potential dispersal range, than planktotrophic larvae, which typically capture zooxanthellae from the water column. Biogeographic range data, however, do not support this second hypothesis: modern Indo-Pacific brooding and broadcasting genera have nearly identical ranges, and many brooding species have narrower longitudinal ranges than do broadcasting species. Preferential survivorship of brooding corals contrasts sharply with survivorship patterns among molluscs during extinction events; among molluscs, broadcasters are favored over brooders.A major increase in upwelling at the Oligocene/Miocene boundary was probably responsible for this extinction/geographic restriction event. Preferential survival of brooding and mixed mode coral genera appears to be a product of their being better able to recruit and survive in marginal conditions such as upwelling zones.

We analyzed the δ18O and δ13C time-series contained in coral skeletons collected from Isla del Cano, Costa Rica, that survived the 1982–1983 El Nino warming event. Coral δ18O give a record of thermal histories with a precision of ~0.5°C. For this locality, we have determined that the average Δδw effect in the coral skeletons is equivalent to 33% of the skeletal δ18O range. Therefore, if δw effects are not compensated for, the annual skeletal-δ18O range displays a temperature range of 1 °C lower than actual values. The isotopic record of Porites lobata skeletons shows simultaneous depletions in 18O and 13C at skeletal levels corresponding to 1983, coincident with the El Nino/Southern Oscillation (ENSO) event. Therefore, the El Nino event is not only recorded as negative δ18O anomalies in the skeleton, suggesting the warming of ambient waters, but also in the δ13C signal as negative anomalies, indicating coral bleaching. Contrary to the predictions of the “13C-insolation model” that the annual carbon isotope variation should be attenuated with depth in proportion to the decrease in light-intensity variation with depth, we found a clear trend where Δδ13C increases with depth. Coral bioenergetics, which depends on both coral physiology and ecology, may adequately explain the unexpected increase in δ13C range with depth, without contradicting the seasonal character of δ13C variability with the solar irradiance cycle. Although some authors have determined the presence of hiatuses in the skeletal record due to severe stress and growth cessation, in this study it has been found that skeletal growth was not seriously diminished during the El Nino year of 1983. We attribute the good agreement of the δ18O record with the timing and magnitude of the El Nino 1982–1983 warming event to the nature of the warming trend in the area, as well as to some synergistic implications of coral tolerance to thermal stress.

Effective tools for monitoring the status of ecological restoration projects are critical for the management of restoration programs. Such tools must integrate disparate data comprised of multiple variables that describe restoration status, including the condition of environmental stressors, landscape connectivity, ecosystem resilience, and ecological structure and function, while communicating these concepts effectively to a wide range of stakeholders. In this paper we describe the process of constructing multimetric indices (MMIs) for monitoring restoration status for restoration projects currently underway on the eastern coast of Saudi Arabia. During this process, an initial suite of measurements is filtered for response and sensitivity to ecosystem stressors, eliminating measurements that provide little information and reducing future monitoring efforts. The retained measurements are rescaled into comparable domain metrics and assembled into MMIs. The MMIs are presented in terms of established restoration theories, including restoration trajectory and restoration endpoint targets.

Stable nitrogen isotope (delta(15)N) analysis has proven an effective "fingerprint" of sewage contamination in coral reef environments; however, short-term variability in nitrogen cycling and isotopic fractionation may obscure long-term trends. Here, we examine delta(15)N signatures in the organic endoskeletons of long-lived (20-40 years) gorgonian corals. Specimens were collected from relatively pristine reefs off Green Turtle Cay, Bahamas, and from reefs off southeast Florida heavily impacted by multiple sources of anthropogenic nitrogen. The delta(15)N of the most recently grown skeleton (branch tips) ranged from +2 to +3 per thousand at Green Turtle Cay, and +4.5 to +10 per thousand off Florida. These values closely match the delta(15)N of macroalgae collected from the same locations, indicating that gorgonian corals are isotopically similar to primary producers, and therefore suitable for assessing sources of dissolved inorganic nitrogen. Differences in the delta(15)N between younger and older skeleton indicated an overall decline of -0.34 +/- 0.06 per thousand (1 s.e) over the last 20 - 40 years at Green Turtle Cay, reflecting a possible increase in nitrogen fixation and/or atmospheric deposition of anthropogenic nitrogen. Off southeast Florida, there was an overall increase in delta(15)N over the same time period, reflecting increasing wastewater discharges from the rapidly growing population. These results highlight the usefulness of delta(15)N recorded in gorgonians and other long-lived organisms in assessing spatiotemporal patterns of nitrogen sources to coastal marine environments.

Recent ecological and oceanographic evidence has demonstrated that coral recruitment can be highly localised and very successful in areas of high water residence time (eddy areas) on coral reefs. These areas occur in the lee of time-averaged and depth-averaged far-field currents. In this study, several reefs in the central region of the Great Barrier Reef, Australia, were examined to determine the relationship between asymmetry in reef geomorphology, wind direction, time- and depth-averaged currents, particularly during the coral spawning season. Detailed fine-scale bathymetric data were plotted in three dimensions for four reefs: Helix Reef, Wheeler Reef, Myrmidon Reef, and Rib Reef. The perspective from which each reef was viewed was rotated until maximum asymmetry (steep vs. gentle slope) from the floor of the continental shelf to the ocean's surface was achieved. The compass orientation of the reef's asymmetry was then compared with known directions of tradewinds and time- and depth-averaged currents. Asymmetry in overall reef geomorphology was found generally not to be related to tradewinds or resultant surface-driven currents. It was, however, found to be more closely associated with time- and depth-averaged seasonal currents, often prevailing at the time of coral spawning. We propose that far-field currents, near-field currents, and coral recruitment processes prevailing during the time of coral spawning have differentially enhanced lateral extension of the reef in a direction “down-current” far-field currents through geological time. We also propose that this relationship may be of assistance in hind-casting seasonal low-velocity, depth- and time-averaged palaeo-currents surrounding fossil reefs, in addition to tools already available for hind-casting wind-forced surface currents and waves.

Surficial sediment samples and specimens of the filter-feeding marine mussel, Mytilus edulis, were collected at thirteen sites near a Pb/Zn ore stockpile and smelting complex (Canada). Aside from measuring the total S content in the sediment samples, each of these samples were subjected to a sequential extraction procedure designed to determine the partitioning of Fe and Pb among various geochemical phases and compared with the Pb levels measured in the mussel tissues. About one third of the Fe and more than 90% of the Pb were extracted from the sediments. Sediments collected within Belledune Harbour generally yielded the greatest amount of Pb whereas the highest levels of S were measured in Dalhousie Harbour sediments. Regression analysis indicated that the total S content in the sediments played an important role in defining the Pb accumulation in the mussel tissues.