331 resultados para Coral reef sponges


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Several small scleractinian coral colonies were collected from a remote reef and transferred [to] the Louisiana Universities Marine Center (LUMCON) for in vitro reproductive and larval studies. The species used here were Porites astreoides and Diploria strigosa. Colony size was ~20 cm in diameter. Colonies were brought to the surface by liftbag and stored in modified ice coolers. They were transported from Freeport, TX to Cocodrie, LA by truck for nearly 15 hours where field conditions were simulated in waiting aquaria. This document describes the techniques and equipment that were used, how to outfit such aquaria, proper handling techniques for coral colonies, and several eventualities that the mariculturist should be prepared for in undertaking this endeavor. It will hopefully prevent many mistakes from being made.

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The stress response, at the molecular level, of the soft corals Dendronephthya klunzingeri and Heteroxenia sp., hard corals Acropora hyacinthus and A. valenciennesi, an ascidian Symplegma sp. and sponges Latruncula cortica and Callyspongia crassa to germanium oxide (GeO sub(2)) was evaluated. Evaluation was carried out using bioindicators. such as the level of expression of each of the heat shock proteins (HSPs) and the silicatein enzyme in response to the compound. However, the expression was measured by SDS Polyacrylamide Gel Electrophoresis (SDS PAGE) and western blotting. The harmful concentration of GeO sub(2) that produced noticeable molecular changes in the studied samples during the first 6-24 hours was 6 μg/ml. The two studied soft corals as well as the ascidian responded to the harmful concentration of germanium oxide by expressing the heat-shock protein 90 (hsp90), while the two hard corals responded by expressing hsp70, C. crassa by decreasing the level of silicatein enzyme and sponge L. cortica produced no change by any of the used biomarkers, The soft coral Heteroxenia sp. was found to be sensitive to mechanical stress during the experiment and it was more sensitive to 6 μg/ml of GeO sub(2) than the other soft coral D. klunzingeri. The two studied hard corals were sensitive to mechanical stress during the experiment, but A. hyacinth us showed higher sensitivity than A. valenciennesi. However, these 2 corals displayed reverse response to GeO sub(2). Primitive evidences were found in the SDS PAGE to distinguish the tissue of the soft coral from that of the hard coral on the molecular level; the soft coral showed two prominent protein bands (45 and 50 kDa) while the two prominent protein bands for hard corals were 31 and 116 kDa.

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Scleractinian coral species harbour communities of photosynthetic taxa of the genus Symbiodinium. As many as eight genetic clades (A, B, C, D, E, F, G and H) of Symbiodinium have been discovered using molecular biology. These clades may differ from each other in their physiology, and thus influence the ecological distribution and resilience of their host corals to environmental stresses. Corals of the Persian Gulf are normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. This study is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs to the level of phylogenetic clades. Samples of eight coral species were collected at two different depths from the eastern part of Kish Island in the northern Persian Gulf. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by Polymerase Chain Reaction (PCR). PCR products were analyzed using Single Stranded Conformational Polymorphism (SSCP) and phylogenetic analyses of the LSU DNA sequences from a subset of the samples. The results showed that Symbiodinium populations were generally uniform among and within the populations of 8 coral species studied, and there are at least two clades of Symbiodinium from Kish Island. Clade D was detected from 8 of the coral species while clade C90 was found in 2 of species only (one species hosted two clades simultaneously). The dominance of clade D might be explained by high temperatures or the extreme temperature variation, typical of the Persian Gulf.

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In the present investigation the marine bacteria isolated from corals, sponges sea water and sediments of coral regions in the larak Island located in the Persian Gulf and were examined for ability to produce cytotoxic metabolits in order to use as an anticancer compounds. Cytotoxic effect were isolated bacteria from different samples and were examined by Artemia Cytotoxic Bioassay test, in which 4.5 percent of sea waters, 12 percent of sediments and 28 percent of marine invertebrat showed cytotoxic activity, using Brine Shrimp Bioassay test. Streptomyces S-2004 isolated from soft coral specified as Sinularia erecta had LC50=0.5mg/m1 in Brine Shrimp Bioaassay test. The streptomyces S-2004 produced cytotoxic metabolits in low nutrient condition and sea water medium after 7 days on 250 rpm shaken in vitro condition. The extract partially were semipurified. Then ethyl acetate extraction from aceton extracted of bacterial plate had cytotoxic effect (LC50=4.19ktg/m1) in Human epidermoid carcinoma of mouth cells (KB) by using neutral red assay. Morphological effects of this extract on KB cells showed turgescence, cellular blebs and apoptosis which was a proof for anticancer compounds of the extract. It is seems that streptomyces S-2004 is a new strain and could be introduced as a talented bacteria, which produced cytotoxic metabolits.

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(Document pdf contains 42 pages)

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(Document pdf contains 64 pages)

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(Document pdf contains 9 pages)

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(Document pdf contains 25 pages)

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Bolsa Chica Artificial Reef (BCAR) was constructed in November 1986 with 10,400 tons of concrete rubble and eight concrete and steel barges. Prior to any additional augmentation of BCAR, the u.s. Army Corps of Engineers and the California Coastal Commission required the California Department of Fish and Game (CDFG) to survey the bioloqical communities on and around BCAR. In April 1992, qualitative surveys of the biological communities were conducted on one of the eight modules at BCAR and at a nearby sand-only site. One of the modules, Module D, located in 90 feet of water (MLLW), was surveyed for fish, macroinvertebrates, and turf community organisms (small plants and sessile animals). Twelve species of fish were observed, including kelp bass (Paralabrax clathratus) and barred sand bass (P. nebulifer). Eight macroinvertebrate species were observed, rock scallops (Crassedoma giganteum) being the most abundant. The turf community was comprised of thirteen invertebrate taxa, among which erect ectoprocts (Bugula spp.) were the most numerous. Two species of foliose red algae (Rhodymenia pacifica and Anisocladella pacifica) were also observed. The reef has reached an advanced stage of successional development with fish and invertebrate communities diverse and well established. However, due,.to its depth and the turbidity of surrounding waters, this reef is not likely to ever support a diverse algal community. The diversity and abundance of fish and macroinvertebrates were, as to be expected, much lower in the nearby sand-only site. Only two species of fish and seven macroinvertebrate species were observed. Of these, only the sea pen, Stylatula elongata, was common. Overall, when compared to nearby sand-only habitats, Bolsa Chica Artificial Reef appears to contribute substantially to the local biological productivity. In addition, the concrete rubble used in BCAR' s construction appears to be performing as well as the quarry rock used in all of CDFG's experimental reefs. (Document pdf contains 22 pages)

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(PDF has 2 pages.)

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Mollusks were sorted from samples of shell hash (obtained as bycatch during NOAA-sponsored studies of larval and juvenile fish distribution), and analyzed to gain qualitative insights on species composition, distribution and habitat affinities of the molluscan fauna on the continental shelf off Georgia. Samples came from beam trawls at 37 stations located in the immediate vicinity and offshore of the Gray’s Reef National Marine Sanctuary (GRNMS) at depths of 4.9 to 103 m. Two hundred sixty-three (263) taxa of mollusks (~58% as dead shells only) were collected, and nearly all (~99%) were identified to the species level. Ninety-seven of these taxa appeared in samples from one or more of the four stations established near the corners of the GRNMS. Samples were highly variable in terms of appearance, volume and species composition of mollusks, reflecting the extreme patchiness of benthic habitats within this region of the continental shelf. With very few exceptions, the mollusks were generally characteristic of either the Carolinian or Caribbean faunal provinces. The Georgia continental shelf, however, was outside the previously reported ranges for at least 16 of the species reported here. Most of these extralimital species were known previously from the East Coast of Florida, and represented northerly range extensions of 1-5° Latitude (110-560 km). One species represented a more significant range extension from the Bahamas and the southern Caribbean, and two represented southerly range extensions, known previously from only as close as off North Carolina. The high incidence of range extensions found in this study and the potential for discovery of additional species are discussed in the context of the diversity and patchiness of benthic habitats on the continental shelf of the region, and the sensitivity of species recruitment to variability in Gulf Stream patterns and global climate change. (PDF contains 52 pages)

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For many fish stocks, resource management cannot be based on stock assessment because data are insufficient-a situation that requires alternative approaches to management. One possible approach is to manage data-limited stocks as part of an assemblage and to determine the status of the entire unit by a data-rich indicator species. The utility of this approach was evaluated in analyses of 15 years of commercial and 34 years of recreational logbook data from reef fisheries off the southeastern United States coast. Multivariate statistical analyses successfully revealed three primary assemblages. Within assemblages, however, there was little evidence of synchrony in population dynamics of member species, and thus, no support for the use of indicator species. Nonetheless, assemblages could prove useful as management units. Their identification offers opportunities for implementing management to address such ecological considerations as bycatch and species interrelations.

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Introduction: The National Oceanic and Atmospheric Administration’s Biogeography Branch has conducted surveys of reef fish in the Caribbean since 1999. Surveys were initially undertaken to identify essential fish habitat, but later were used to characterize and monitor reef fish populations and benthic communities over time. The Branch’s goals are to develop knowledge and products on the distribution and ecology of living marine resources and provide resource managers, scientists and the public with an improved ecosystem basis for making decisions. The Biogeography Branch monitors reef fishes and benthic communities in three study areas: (1) St. John, USVI, (2) Buck Island, St. Croix, USVI, and (3) La Parguera, Puerto Rico. In addition, the Branch has characterized the reef fish and benthic communities in the Flower Garden Banks National Marine Sanctuary, Gray’s Reef National Marine Sanctuary and around the island of Vieques, Puerto Rico. Reef fish data are collected using a stratified random sampling design and stringent measurement protocols. Over time, the sampling design has changed in order to meet different management objectives (i.e. identification of essential fish habitat vs. monitoring), but the designs have always remained: • Probabilistic – to allow inferences to a larger targeted population, • Objective – to satisfy management objectives, and • Stratified – to reduce sampling costs and obtain population estimates for strata. There are two aspects of the sampling design which are now under consideration and are the focus of this report: first, the application of a sample frame, identified as a set of points or grid elements from which a sample is selected; and second, the application of subsampling in a two-stage sampling design. To evaluate these considerations, the pros and cons of implementing a sampling frame and subsampling are discussed. Particular attention is paid to the impacts of each design on accuracy (bias), feasibility and sampling cost (precision). Further, this report presents an analysis of data to determine the optimal number of subsamples to collect if subsampling were used. (PDF contains 19 pages)