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Oyster habitat restoration seeks to recover lost ecosystem services including increased provisioning of refuge and foraging habitat for fish and invertebrate communities. The goal of this study was to quantify the ecosystem service benefit of habitat provisioning in Ninigret Pond, RI, following oyster restoration. Four metrics were measured, abundance, biomass, species richness, and diversity, as well as isotopic composition in fish and invertebrates collected seasonally from restored oyster, aquaculture, and bare sediment sites, to examine whether the oyster habitat outperformed the bare sediment habitat. Sampling locations were chosen in Foster's Cove north and south. Grassy Point, South Sanctuary, and an Aquaculture lease; each had two restored oyster sites and one bare sediment site. Each site was sampled using a box trap, seine net, shrimp trap, and minnow trap. Oyster habitats had significantly greater metrics than did bare sediment habitats in some comparisons from the box trap and seine net samples. Restored oyster sites at South Sanctuary had lower metric values than the other oyster sites. Metrics from the Aquaculture sites were comparable to the Foster's Cove and Grassy Point restored oyster sites and often outperformed South Sanctuaryrestored oyster sites. Seasonally, spring and autumn samples tended to have higher abundance and biomass values than summer samples. Isotopic composition of five species occurring at both restored oyster and bare sediment sites demonstrated some differences in the trophic levels between species but not between habitat types. In Ninigret Pond, fish and invertebrate abundance, biomass, species richness, and diversity benefit from the use of oyster and bare sediment habitats. Coastal zone managers interested in restoring the ecological function of oyster reefs to support fish and invertebrate communities should consider strategically locating restoration projects within the mosaic of structured habitats and monitoring them for selected ecosystem services. KEY WORDS: nekton, habitat preference, oyster reef, aquaculture, restoration, INTRODUCTION During the past century, degradation of habitats and the ecosystem services they provide in coastal and marine environments has resulted from multiple stressors including nutrient pollution, overexploitation of resources, [...]

Habitat availability underpins the diversity and distribution of benthic marine communities. Sponges are significant structural components of seabeds; therefore, understanding sponge-community associations are important for the effective management of marine biodiversity. Invertebrate communities were quantified from 11 sponge species having distinct morphologies from Ningaloo Reef (tropical) and Rottnest Island (temperate), Western Australia. Communities from substrate adjacent to sponges were additionally sampled for comparisons to sponge-associated fauna. Gross and fine-scale morphological features of sponge host species were quantified to assess their effects on faunal abundance and diversity. A total of 3966 individuals from 125 taxa were extracted, showing low co-occurrences of taxa from both sponges and the surrounding substrate (Ningaloo 8.9%; Rottnest 11.2%). Four out of the 11 sponges supported higher fauna abundance compared to their surrounding substrate, including Haliclona sp. NTM148 (Ningaloo; 1.21 ± 0.54 N.cm.sup.-3, 60 x higher than substrate) and Monanchora clathrata (Rottnest; 2.87 ± 1.7 N.cm.sup.-3, 32 x higher than substrate). These communities were dominated by the barnacle Acastinae sp.4 (100%) and sedentary polychaete Spionidae sp. 1 (99%), respectively, highlighting strong host-specific associations. Sponge size (volume), % of internal space, minimum diameter of internal space, and gross morphological complexity were important at explaining variation in faunal assemblage, with larger sponges having more internal space of larger minimum canal diameter supporting higher community abundance. This study highlights the significance of large and long-lived sponges as sources of unique marine biodiversity that are yet to be discovered and the importance of sponge gardens for the conservation of cryptic marine biodiversity., Author(s): Ying-Yueh Chin [sup.1], Jane Prince [sup.1], Gary Kendrick [sup.1], Muhammad Azmi Abdul Wahab [sup.2] Author Affiliations: (1) grid.1012.2, 0000 0004 1936 7910, School of Biological Sciences, Indian Ocean Marine [...]

High temperatures disrupt coral-algal symbioses in multiple ways, with negative impacts on the physiology of the coral host, the algal symbiont, and the combined holobiont. Most heat stress studies on hard corals have understandably focused on species trends based on the combined observation of multiple individuals to account for phenotypic plasticity among colonies. As the 'average coral' continues to decline while sea temperatures rise, the outlier colonies that exhibit neutral or positive responses to heat stress are coming to represent larger proportions of marginal coral populations. These colonies are those most likely to guide the future trajectory of reef ecosystems, but their dynamics are often obscured by aggregate analyses. To directly measure and analyze intraspecific variation in heat stress responses within a natural coral population, we performed aquarium experiments on sixteen colonies of the structurally important branching coral Montipora digitata from Okinawa Island, Japan. We resolved host and symbiont genotypes, exposed replicate coral fragments to ambient or elevated temperature, and monitored stress-driven differences in host calcification, symbiont photochemistry, and colony mortality. Over the 6-month experiment, six colonies appeared to tolerate stress (exhibiting no major physiological changes), seven were sensitive to stress (exhibiting reduced growth), and three expired. Both host and symbiont genotype contributed to this variation. These results demonstrate the degree to which unique M. digitata holobionts may differentially respond to thermal stress in warming oceans and highlight the important role of intraspecific variation in shaping future reef assemblages., Author(s): Javid Kavousi [sup.1] [sup.2], Vianney Denis [sup.3], Victoria Sharp [sup.4] [sup.5], James Davis Reimer [sup.1] [sup.4] [sup.6], Takashi Nakamura [sup.1] [sup.6] [sup.7], John Everett Parkinson [sup.4] [sup.8] Author Affiliations: [...]

Abstract: An updated checklist of cartilaginous and bony fishes from reefs and nearby areas around Clipperton Atoll (eastern Pacific) is presented. The register was compiled from field surveys between 1997 [...]

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1600-0706.2008.17410.x Byline: Mark I. McCormick Abstract: Maternal effects are increasingly being recognized as an important pre-natal source of life history variation in the next generation. The present study uses a field experiment to explore the influence of heterospecific interactions on the reproductive output and offspring characteristics of a common Indo-Pacific damselfish, Pomacentrus amboinensis. On the Great Barrier Reef pairs of breeding P. amboinensis were placed on isolated patch reefs and to half of the pairs resource competitors (other planktivorous damselfishes), and predators of eggs and juveniles were added. Females inhabiting patches with heterospecifics had more aggressive interactions and higher levels of the stress hormone, cortisol. Neither the number of clutches nor number of eggs produced differed among treatments. The size of larvae at hatching was found to be reduced as a result of the stress associated with increased interactions with heterospecific and the transfer of cortisol to offspring. This stress-associated mechanism appears to be an important and directional source of life history variability, but the individual nature of the maternal response is likely to result in a conclusion of a diversified bet hedging reproductive strategy when viewed at the local population level. These findings highlight the complex determinants of individual success and the important role of parental well-being in the population dynamics of the next generation. Article History: Manuscript Accepted 12 November 2008 Article note: M. I. McCormick (mark.mccormick@jcu.edu.au), School of Marine and Tropical Biology, James Cook Univ., Townsville, Queensland 4811, Australia.

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1600-0706.2008.16955.x Byline: F. Bulleri, L. Tamburello, L. Benedetti-Cecchi Abstract: Despite the great interest for the role played by resident assemblages in regulating biological invasions, few studies have assessed how these can influence the spread of exotic species that have successfully established or have included more than one trophic level. On shallow rocky reefs, we assessed how the effects of different benthic assemblages on the spread of an invasive alga, Caulerpa racemosa, are influenced by alterations in the density and species composition of the resident sea urchin assemblage. In order to simulate herbivore species loss scenarios, assemblages dominated by different morphological groups of algae (i.e. turfs or encrusting corallines) or experimentally cleared plots (i.e. bare rock) were exposed to grazing by different combinations of species (Arbacia lixula and Paracentrotus lividus) and densities (natural, -50% and -100% of natural densities) of urchins. Algal turfs and encrusting corallines generally facilitated C. racemosa. Manipulating urchins assemblages did not affect the cover and density of fronds of C. racemosa. In contrast, halving the density of P. lividus favoured the penetration of stolons of C. racemosa, consistently among algal assemblages. Other effects of urchins varied among algal assemblages, indicating interactions between trophic levels. In algal turfs, the total removal of urchins caused a decrease in the penetration of stolons, while it enhanced the length of fronds, indicating a shift in the growth form of this clonal plant and, ultimately, a depression of its spreading ability. In bare or encrusting corallines dominated surfaces, the removal of urchins had positive effects on the penetration of stolons and on the length of fronds of C. racemosa, irrespective of one or two species being manipulated and for the intensity of their removal. Our results show that tradeoffs between negative and positive effects of herbivores, varying according to relative densities of species and to the direction and strength of the effects of resident plant assemblages, can influence local rates of spread of C. racemosa. Thus, not only facilitation of exotics by natives can be key in enhancing the spread of exotic species, but it can occur between organisms at different trophic levels. Finally, our findings have important implications for the management of C. racemosa, in view of the progressive domination of shallow rocky reefs by algal turfs. Article History: Manuscript Accepted 29 July 2008 Article note: F. Bulleri (fbulleri@biologia.unipi.it), L. Tamburello and L. Benedetti-Cecchi, Dipto di Biologia, Univ. di Pisa, CoNISMa Via Derna 1, IT-56126, Pisa, Italy.

The biosphere's great carbonate deposits, from caliche soils to deep-sea carbonate oozes, precipitate largely as by-products of autotrophic nutrient acquisition physiologies. Protons constitute the critical link: Calcification generates protons, which plants and photosynthetic symbioses use to assimilate bicarbonate and nutrients. A calcium ATPase-based 'trans' mechanism underlies most biological calcification. This permits high calcium carbonate supersaturations and rapid carbonate precipitation. The competitive advantages of calcification become especially apparent in light and nutrient-deficient alkaline environments. Calcareous plants often dominate the lower euphotic zone in both the benthos and the plankton. Geographically and seasonally, massive calcification concentrates in nutrient-deficient environments including alkaline soils, coral reefs, cyanobacterial mats and coccolithophorid blooms. Structural and defensive uses for calcareous skeletons are sometimes overrated. Keywords: calcium; carbonate; bicarbonate; proton; acid; calcareous; nutrient; reef

Halimeda reefs in the upper Miocene strata ([approximately to]6 Ma) of the Sorbas basin, southeastern Spain, shed light on the internal structure of more extensive but less accessible Holocene counterparts, and challenge conventional reef concepts. Coarse discoid segments, released by Halimeda during life or immediately after death, dominate the lenslike mounds. Their chaotic, loose appearance disguises the reefal nature of the mounds. Segments, accumulating at or very close to sites of growth, were quickly stabilized by microbial and cement crusts that bound them into distinctive rigid gravel fabrics. This early lithification generated relief but inhibited off-mound export of sediment, although large blocks detached locally and moved downslope. Encrustation of parautochthonous Halimeda gravel created a unique reef type: segment reefs.

The indication of fecal pollution by measuring coliphage abundance is discussed. Water column and sediments from Florida Bay across Key Largo to the edge of the Florida Shelf were analyzed for total, coliphage and marine host isolate virus abundance by viral, sediment and bacterial direct counts. Results indicate that phage was abundant in the Key Largo during winter and that factors determining their distribution in the water column were different from from those in the sediments.

This communication describes the study of an ecological system using remote-sensing data and image-analysis tools derived from possibility theory. Possibility theory enables I he construction of membership functions using a multisource fusion algorithm. The sources of information are the sampled training stations. We test to see if the possibilistic algorithm is able to provide results with an accuracy at least equal to that provided by traditional probabilistic-classification algorithms. Then, for each pixel, we analyze the hierarchy of membership degrees output by the fusion to study the spatial structure of an ecosystem composed of objects that lack precise boundaries. We characterize patches or gradients, boundary rates, and transition states. As an example, a scheme of analysis for underwater reefscapes at Moorea Island, French Polynesia, is proposed. The nonparametric multisource fusion method has an accuracy of 82% (overall normalized-percentage agreement), while a probabilistic maximum-likelihood classifier has an accuracy of 73%. The analysis of the hierarchy of membership degrees indicates that almost 25% of Moorea Island lagoon is heterogeneous, composed of real boundaries, transition states, and fragmented zones. Index Terms--Indeterminate boundaries, multisource fusion, possibility theory, reefscape, spatial analysis.