10 research outputs found

    Chaetomorpha philippinensis (Cladophorales, Chlorophyta), a new marine microfilamentous green alga from tropical waters

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    A new marine microfilamentous green alga, Chaetomorpha philippinensis Leliaert sp. nov., is described as an epiphyte on Chaetomorpha vieillardii from shallow subtidal habitats in the Philippines. Phylogenetic analyses of large subunit rDNA and rDNA internal transcribed spacer (ITS) sequences show that the new tropical species is sister to the cold-water Chaetomorpha norvegica, from which it is genetically clearly distinct but morphologically almost indistinguishable. Chaetomorpha philippinensis is characterized by minute, straight or curved, unbranched, erect filaments up to 300 mu m long and 7-17 mu m in diameter, attached by a basal, hapteroid holdfast. Filaments in culture are similar in morphology but grow considerably longer with slightly larger cells. The cylindrical cells are multinucleate with up to eight nuclei (up to 18 in culture). Cells contain a single, parietal, lobed chloroplast with numerous small perforations and one to several pyrenoids. Zoosporangia develop by transformation of apical and subapical cells with zoids emerging through a domed pore in the apical, middle or basal part of the cell

    A long-term, spatially replicated experimental test of the effect of marine reserves on local fish yields

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    Do no-take marine reserves affect fishery yields? Manipulations of reserve status, and yield estimates, were made at two Philippine islands over two decades. Twenty-five percent and ten percent, respectively, of the coral reefs at Sumilon and Apo islands were made no-take reserves in 1974 and 1982. Biomass of target fish increased inside the no-take reserves 3- to 4.5-fold over 9–18 years. Biomass did not increase outside each reserve. Protection of the Sumilon reserve ceased in 1984. Biomass of targeted fish in the reserve and trap and gillnet catches of these fish declined by 42.7% and 40%, respectively, by 1985. The reserve was reprotected from 1987 to 1991 and from 1995 to 2001. Fish biomass increased in the reserve by 27.2%. Trap and gillnet catches outside the reserve increased 26.9% by 2001. The Apo reserve was protected from 1982 to 2001. Total catch of major fish families was significantly higher after (1985–2001) than before (1981) reserve establishment at Apo, increasing 41.3% between 1981 and 1998–2001. These experiments, plus spillover evidence, suggest that marine reserves may help maintain, or even enhance, local fishery yields in the long-term

    Marine reserve benefits local fisheries

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    Abstract. The utility of no-take marine reserves as fisheries-management tools is controversial. It is hypothesized that marine reserves will help to sustain fisheries external to them by becoming net exporters of adults (the ''spillover effect'') and net exporters of propagules (the ''recruitment effect''). Local fishery benefits from spillover will likely generate support from fishing communities for marine reserves. We used underwater visual census to show that biomass of Acanthuridae (surgeonfish) and Carangidae (jacks), two families of reef fish that account for 40-75% of the fishery yield from Apo Island, Philippines, tripled in a well-protected no-take reserve over 18 years (1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001). Biomass of these families did not change significantly over the same period at a site open to fishing. The reserve protected 10% of the total reef fishing area at the island. Outside the reserve, biomass of these families increased significantly closer to (200-250 m) than farther away from (250-500 m) the reserve boundary over time. We used published estimates of fishery catch and effort, and fisher interviews (creel surveys) to show that the total catch of Carangidae and Acanthuridae combined at Apo Island was significantly higher after (1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001) than before (1981) reserve establishment. Hook-and-line catch per unit effort (CPUE) at the island was 50% higher during 1998-2001 (reserve protected 16-19 years) than during 1981-1986 (pre-reserve and early phases of reserve protection). Total hook-and-line effort declined by 46% between 1986 and 1998-2001. Hook-and-line CPUE of Acanthuridae was significantly higher close to (within 200 m) than far from the reserve. CPUE of Carangidae was significantly higher away from the reserve, possibly reflecting a local oceanographic effect. The benefits of the reserve to local fisheries at the island were higher catch, increased catch rate, and a reduction in fishing effort. The fishery and tourism benefits generated by the reserve have enhanced the living standard of the fishing community

    Extensive cryptic species diversity and fine-scale endemism in the marine red alga Portieria in the Philippines

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    We investigated species diversity and distribution patterns of the marine red alga Portieria in the Philippine archipelago. Species boundaries were tested based on mitochondrial, plastid and nuclear encoded loci, using a general mixed Yule-coalescent (GMYC) model-based approach and a Bayesian multilocus species delimitation method. The outcome of the GMYC analysis of the mitochondrial encoded cox2-3 dataset was highly congruent with the multilocus analysis. In stark contrast with the current morphology-based assumption that the genus includes a single, widely distributed species in the Indo-West Pacific (Portieria hornemannii), DNA-based species delimitation resulted in the recognition of 21 species within the Philippines. Species distributions were found to be highly structured with most species restricted to island groups within the archipelago. These extremely narrow species ranges and high levels of intra-archipelagic endemism contrast with the wide-held belief that marine organisms generally have large geographical ranges and that endemism is at most restricted to the archipelagic level. Our results indicate that speciation in the marine environment may occur at spatial scales smaller than 100 km, comparable with some terrestrial systems. Our finding of fine-scale endemism has important consequences for marine conservation and management

    Guidelines for conducting integrated environmental assessment

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    Integrated Environmental Assessments (IEA) are powerful tools to help inform the development of evidence-based environmental policy and decision making, bring relevant scientific findings to a broad audience and raise awareness of changing environmental conditions as well as identify emerging environmental issues. Integrated Environmental Assessments also provide a forum for stakeholders, including scientists, policy-makers, and decision-makers to interact and discuss environmental issues and potential solutions. Integrated Environmental Assessments have been part of the environmental management landscape following up on the Resolution 2997 of the 1972 United Nations (UN) Conference on The Human Environment, Stockholm, that stated, in part, that UNEP "should keep the global environment under review". These assessments have grown to become a major and common feature of environmental management conducted by various stakeholders. For these assessments to be most useful, they must be performed in a consistent manner. For this reason, Member States of the United Nations Environment Programme (UN Environment) requested that guidelines be developed for conducting Integrated Environmental Assessments. These guidelines are advisory and provide approaches for conducting a large gamut of integrated environmental assessments for different objectives. They are intended to be practical in application and sensitive to different levels of available resources and objectives and further complement environmental management monitoring and evaluation programmes

    Extinction risk assessment of the world's seagrass species

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    Seagrasses, a functional group of marine flowering plants rooted in the world's coastal oceans, support marine food webs and provide essential habitat for many coastal species, playing a critical role in the equilibrium of coastal ecosystems and human livelihoods. For the first time, the probability of extinction is determined for the world's seagrass species under the Categories and Criteria of the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. Several studies have indicated that seagrass habitat is declining worldwide. Our focus is to determine the risk of extinction for individual seagrass species, a 4-year process involving seagrass experts internationally, compilation of data on species' status, populations, and distribution, and review of the biology and ecology of each of the world's seagrass species. Ten seagrass species are at elevated risk of extinction (14% of all seagrass species), with three species qualifying as Endangered. Seagrass species loss and degradation of seagrass biodiversity will have serious repercussions for marine biodiversity and the human populations that depend upon the resources and ecosystem services that seagrasses provide

    Data from: Evidence of host-associated divergence from coral-eating snails (genus Coralliophila) in the Coral Triangle

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    We studied how host-associations and geography shape the genetic structure of sister species of marine snails Coralliophila radula (A. Adams, 1853) and C. violacea (Kiener, 1836). These obligate ectoparasites prey upon corals and are sympatric throughout much of their ranges in coral reefs of the tropical and subtropical Indo-Pacific. We tested for population genetic structure of snails in relation to geography and their host corals using mtDNA (COI) sequences in minimum spanning trees and AMOVAs. We also examined the evolutionary relationships of their Porites host coral species using maximum likelihood trees of RAD-seq (restriction site-associated DNA sequencing) loci mapped to a reference transcriptome. A maximum likelihood tree of host corals revealed three distinct clades. Coralliophila radula showed a pronounced genetic break across the Sunda Shelf (Φ CT = 0.735) but exhibited no genetic structure with respect to host. C. violacea exhibited significant geographic structure (Φ CT = 0.427), with divergence among Hawaiian populations, the Coral Triangle and the Indian Ocean. Notably, C. violacea showed evidence of ecological divergence; two lineages were associated with different groups of host coral species, one widespread found at all sites, and the other restricted to the Coral Triangle. Sympatric populations of C. violacea found on different suites of coral species were highly divergent (Φ CT = 0.561, d = 5.13%), suggesting that symbiotic relationships may contribute to lineage diversification in the Coral Triangle
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