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The Ecology of Fishes on Coral Reefs

Citation Information: The Ecology of Fishes on Coral Reefs. Edited by Peter F. Sale. Academic Press. San Diego. 1991. 754 pages. $75.00. (Available from the American Fisheries Society for $71.25.)

Description: This book provides a comprehensive and up-to-date review of the ecology of coral reef fishes presented by top researchers from North America and Australia. Immense strides have been made over the past twenty years in our understanding of ecological systems in general and of reef fish ecology in particular. Many of the methodologies that reef fish ecologists use in their studies will be useful to a wider audience of ecologists for the design of their ecological studies. Significant among the impacts of the research on reef fish ecology are the development of nonequilibrium models of community organization, more emphasis on the role of recruitment variability in structuring local assemblages, the development and testing of evolutionary models of social organization and reproductive biology, and new insights into predator-prey and plant-herbivore interactions.

Top 10 List: 
Coral Reef Management

Reduction of Wind and Swell Waves by Mangroves

Citation Information: McIvor, A.L., Möller, I., Spencer, T. and Spalding. M. (2012) Reduction of wind and swell waves by mangroves. Natural Coastal Protection Series: Report 1. Cambridge Coastal Research Unit Working Paper 40. Published by The Nature Conservancy and Wetlands International. 27 pages. ISSN 2050-7941.

Executive Summary: Coastal populations are particularly vulnerable to the impacts of extreme events such as storms and hurricanes, and these pressures may be exacerbated through the influence of climate change and sea level rise. Coastal ecosystems such as mangrove forests are increasingly being promoted and used as a tool in coastal defence strategies. There remains, however, a pressing need to better understand the roles that ecosystems can play in defending coasts. This report focuses on mangrove forests and the role they can play in reducing wind and swell waves. While mangrove forests are usually found on shores with little incoming wave energy, they may receive larger waves during storms, hurricanes and periods of high winds. Large wind and swell waves can cause flooding and damage to coastal infrastructure. By reducing wave energy and height, mangroves can potentially reduce associated damage.

All evidence suggests that mangroves can reduce the height of wind and swell waves over relatively short distances: wave height can be reduced by between 13 and 66% over 100 m of mangroves. The highest rate of wave height reduction per unit distance occurs near the mangrove edge, as waves begin their passage through the mangroves.

A number of characteristics of mangroves affect the rate of reduction of wave height with distance, most notably the physical structure of the trees. Waves are most rapidly reduced when they pass through a greater density of obstacles. Mangroves with aerial roots will attenuate waves in shallow water more rapidly than those without. At greater water depths, waves may pass above aerial roots, but the lower branches can perform a similar function. The slope of the shore and the height of the waves also affect wave reduction rates through mangroves.

Organic micropollutants in coastal waters from NW Mediterranean Sea: Sources distribution and potential risk

Citation Information: Environment International; Volume 46, 1 October 2012, Pages 50–62

Authors: Juan Sánchez-Avila, Romà Tauler, Silvia Lacorte

Abstract: This study provides a first estimation on the sources, distribution and risk of organic micropollutants (OMPs) in coastal waters from NW Mediterranean Sea. Polycyclic aromatic hydrocarbons, polychlorinated biphenyls, organochlorinated pesticides, polybrominated diphenyl ethers, phthalates and alkylphenols were analyzed by solid phase extraction and gas chromatography coupled to tandem mass spectrometry (SPE–GC–EI-MS/MS). River waters and wastewater treatment plant effluents discharging to the sea were identified as the main sources of OMPs to coastal waters, with an estimated input amount of around of 25,800 g d 1. The concentration of ΣOMPs in coastal areas ranged from 17.4 to 8442 ng L 1, and was the highest in port waters, followed by coastal and river mouth seawaters. A summarized overview of the patterns and sources of OMP contamination on the investigated coastal sea waters of NW Mediterranean Sea, as well as of their geographical distribution was obtained by Principal Component Analysis of the complete data set after its adequate pretreatment. Alkylphenols, bisphenol A and phthalates were the main contributors to ΣOMPs and produced an estimated significant pollution risk for fish, algae and the sensitive mysid shrimp organisms in seawater samples. The combination of GC-MS/MS, chemometrics and risk analysis is proven to be useful for a better control and management of OMP discharges

Detection of a Diverse Marine Fish Fauna Using Environmental DNA from Seawater Samples

Citation Information: Thomsen PF, Kielgast J, Iversen LL, Møller PR, Rasmussen M, et al. (2012) Detection of a Diverse Marine Fish Fauna Using Environmental DNA from Seawater Samples. PLoS ONE 7(8): e41732. doi:10.1371/journal.pone.0041732

Abstract: Marine ecosystems worldwide are under threat with many fish species and populations suffering from human over-exploitation. This is greatly impacting global biodiversity, economy and human health. Intriguingly, marine fish are largely surveyed using selective and invasive methods, which are mostly limited to commercial species, and restricted to particular areas with favourable conditions. Furthermore, misidentification of species represents a major problem. Here, we investigate the potential of using metabarcoding of environmental DNA (eDNA) obtained directly from seawater samples to account for marine fish biodiversity. This eDNA approach has recently been used successfully in freshwater environments, but never in marine settings. We isolate eDNA from ½-litre seawater samples collected in a temperate marine ecosystem in Denmark. Using next-generation DNA sequencing of PCR amplicons, we obtain eDNA from 15 different fish species, including both important consumption species, as well as species rarely or never recorded by conventional monitoring. We also detect eDNA from a rare vagrant species in the area; European pilchard (Sardina pilchardus). Additionally, we detect four bird species. Records in national databases confirmed the occurrence of all detected species. To investigate the efficiency of the eDNA approach, we compared its performance with 9 methods conventionally used in marine fish surveys. Promisingly, eDNA covered the fish diversity better than or equal to any of the applied conventional methods. Our study demonstrates that even small samples of seawater contain eDNA from a wide range of local fish species. Finally, in order to examine the potential dispersal of eDNA in oceans, we performed an experiment addressing eDNA degradation in seawater, which shows that even small (100-bp) eDNA fragments degrades beyond detectability within days.

Spatial Variability of Benthic-Pelagic Coupling in an Estuary Ecosystem: Consequences for Microphytobenthos Resuspension Phenomenon

Citation Information: Ubertini M, Lefebvre S, Gangnery A, Grangeré K, Le Gendre R, et al. (2012) Spatial Variability of Benthic-Pelagic Coupling in an Estuary Ecosystem: Consequences for Microphytobenthos Resuspension Phenomenon. PLoS ONE 7(8): e44155. doi:10.1371/journal.pone.0044155

Abstract: The high degree of physical factors in intertidal estuarine ecosystem increases material processing between benthic and pelagic compartments. In these ecosystems, microphytobenthos resuspension is a major phenomenon since its contribution to higher trophic levels can be highly significant. Understanding the sediment and associated microphytobenthos resuspension and its fate in the water column is indispensable for measuring the food available to benthic and pelagic food webs. To identify and hierarchize the physical/biological factors potentially involved in MPB resuspension, the entire intertidal area and surrounding water column of an estuarine ecosystem, the Bay des Veys, was sampled during ebb tide. A wide range of physical parameters (hydrodynamic regime, grain size of the sediment, and suspended matter) and biological parameters (flora and fauna assemblages, chlorophyll) were analyzed to characterize benthic-pelagic coupling at the bay scale. Samples were collected in two contrasted periods, spring and late summer, to assess the impact of forcing variables on benthic-pelagic coupling. A mapping approach using kriging interpolation enabled us to overlay benthic and pelagic maps of physical and biological variables, for both hydrological conditions and trophic indicators. Pelagic Chl a concentration was the best predictor explaining the suspension-feeders spatial distribution. Our results also suggest a perennial spatio-temporal structure of both benthic and pelagic compartments in the ecosystem, at least when the system is not imposed to intense wind, with MPB distribution controlled by both grain size and bathymetry. The benthic component appeared to control the pelagic one via resuspension phenomena at the scale of the bay. Co-inertia analysis showed closer benthic-pelagic coupling between the variables in spring. The higher MPB biomass observed in summer suggests a higher contribution to filter-feeders diets, indicating a higher resuspension effect in summer than in spring, in turn suggesting an important role of macrofauna bioturbation and filter feeding (Cerastoderma edule).

Investigating the Potential Use of Environmental DNA (eDNA) for Genetic Monitoring of Marine Mammals

Citation Information: Foote AD, Thomsen PF, Sveegaard S, Wahlberg M, Kielgast J, et al. (2012) Investigating the Potential Use of Environmental DNA (eDNA) for Genetic Monitoring of Marine Mammals. PLoS ONE 7(8): e41781. doi:10.1371/journal.pone.0041781

Abstract: The exploitation of non-invasive samples has been widely used in genetic monitoring of terrestrial species. In aquatic ecosystems, non-invasive samples such as feces, shed hair or skin, are less accessible. However, the use of environmental DNA (eDNA) has recently been shown to be an effective tool for genetic monitoring of species presence in freshwater ecosystems. Detecting species in the marine environment using eDNA potentially offers a greater challenge due to the greater dilution, amount of mixing and salinity compared with most freshwater ecosystems. To determine the potential use of eDNA for genetic monitoring we used specific primers that amplify short mitochondrial DNA sequences to detect the presence of a marine mammal, the harbor porpoise, Phocoena phocoena, in a controlled environment and in natural marine locations. The reliability of the genetic detections was investigated by comparing with detections of harbor porpoise echolocation clicks by static acoustic monitoring devices. While we were able to consistently genetically detect the target species under controlled conditions, the results from natural locations were less consistent and detection by eDNA was less successful than acoustic detections. However, at one site we detected long-finned pilot whale, Globicephala melas, a species rarely sighted in the Baltic. Therefore, with optimization aimed towards processing larger volumes of seawater this method has the potential to compliment current visual and acoustic methods of species detection of marine mammals.

Turning up the Heat: Increasing Temperature and Coral Bleaching at the High Latitude Coral Reefs of the Houtman Abrolhos Islands

Citation Information: Abdo DA, Bellchambers LM, Evans SN (2012) Turning up the Heat: Increasing Temperature and Coral Bleaching at the High Latitude Coral Reefs of the Houtman Abrolhos Islands. PLoS ONE 7(8): e43878. doi:10.1371/journal.pone.0043878

Abstract:

Backgr​ound

Coral reefs face increasing pressures particularly when on the edge of their distributions. The Houtman Abrolhos Islands (Abrolhos) are the southernmost coral reef system in the Indian Ocean, and one of the highest latitude reefs in the world. These reefs have a unique mix of tropical and temperate marine fauna and flora and support 184 species of coral, dominated by Acropora species. A significant La Niña event during 2011 produced anomalous conditions of increased temperature along the whole Western Australian coastline, producing the first-recorded widespread bleaching of corals at the Abrolhos.

Methodology/ Principal Find​ings

We examined long term trends in the marine climate at the Abrolhos using historical sea surface temperature data (HadISST data set) from 1900–2011. In addition in situ water temperature data for the Abrolhos (from data loggers installed in 2008, across four island groups) were used to determine temperature exposure profiles. Coupled with the results of coral cover surveys conducted annually since 2007; we calculated bleaching thresholds for monitoring sites across the four Abrolhos groups.

Conclusions/ Sig​nificance

Prioritizing Key Resilience Indicators to Support Coral Reef Management in a Changing Climate

Citation Information: McClanahan TR, Donner SD, Maynard JA, MacNeil MA, Graham NAJ, et al. (2012) Prioritizing Key Resilience Indicators to Support Coral Reef Management in a Changing Climate. PLoS ONE 7(8): e42884. doi:10.1371/journal.pone.0042884

Abstract: Managing coral reefs for resilience to climate change is a popular concept but has been difficult to implement because the empirical scientific evidence has either not been evaluated or is sometimes unsupportive of theory, which leads to uncertainty when considering methods and identifying priority reefs. We asked experts and reviewed the scientific literature for guidance on the multiple physical and biological factors that affect the ability of coral reefs to resist and recover from climate disturbance. Eleven key factors to inform decisions based on scaling scientific evidence and the achievability of quantifying the factors were identified. Factors important to resistance and recovery, which are important components of resilience, were not strongly related, and should be assessed independently. The abundance of resistant (heat-tolerant) coral species and past temperature variability were perceived to provide the greatest resistance to climate change, while coral recruitment rates, and macroalgae abundance were most influential in the recovery process. Based on the 11 key factors, we tested an evidence-based framework for climate change resilience in an Indonesian marine protected area. The results suggest our evidence-weighted framework improved upon existing un-weighted methods in terms of characterizing resilience and distinguishing priority sites. The evaluation supports the concept that, despite high ecological complexity, relatively few strong variables can be important in influencing ecosystem dynamics. This is the first rigorous assessment of factors promoting coral reef resilience based on their perceived importance, empirical evidence, and feasibility of measurement. There were few differences between scientists' perceptions of factor importance and the scientific evidence found in journal publications but more before and after impact studies will be required to fully test the validity of all the factors. The methods here will increase the feasibility and defensibility of including key resilience metrics in evaluations of coral reefs, as well as reduce costs. Adaptation, marine protected areas, priority setting, resistance, recovery.

Effects of Fishing and Regional Species Pool on the Functional Diversity of Fish Communities

Citation Information: Martins GM, Arenas F, Neto AI, Jenkins SR (2012) Effects of Fishing and Regional Species Pool on the Functional Diversity of Fish Communities. PLoS ONE 7(8): e44297. doi:10.1371/journal.pone.0044297

Abstract: The potential population and community level impacts of fishing have received considerable attention, but little is known about how fishing influences communities’ functional diversity at regional scales. We examined how estimates of functional diversity differed among 25 regions of variable richness and investigated the functional consequences of removing species targeted by commercial fisheries. Our study shows that fishing leads to substantial losses in functional diversity. The magnitude of such loss was, however, reduced in the more speciose regions. Moreover, the removal of commercially targeted species caused a much larger reduction in functional diversity than expected by random species deletions, which was a consequence of the selective nature of fishing for particular species traits. Results suggest that functional redundancy is spatially variable, that richer biotas provide some degree of insurance against the impact of fishing on communities’ functional diversity and that fishing predominantly selects for particular species traits. Understanding how fishing impacts community functional diversity is key to predict its effects for biodiversity as well as ecosystem functioning.

Estimating Global “Blue Carbon” Emissions from Conversion and Degradation of Vegetated Coastal Ecosystems

Citation Information: Pendleton L, Donato DC, Murray BC, Crooks S, Jenkins WA, et al. (2012) Estimating Global “Blue Carbon” Emissions from Conversion and Degradation of Vegetated Coastal Ecosystems. PLoS ONE 7(9): e43542. doi:10.1371/journal.pone.0043542

Abstract: Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems—marshes, mangroves, and seagrasses—that may be lost with habitat destruction (‘conversion’). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this ‘blue carbon’ can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15–1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3–19% of those from deforestation globally, and result in economic damages of $US 6–42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats.

Macroalgae Decrease Growth and Alter Microbial Community Structure of the Reef-Building Coral, Porites astreoides

Citation Information: Vega Thurber R, Burkepile DE, Correa AMS, Thurber AR, Shantz AA, et al. (2012) Macroalgae Decrease Growth and Alter Microbial Community Structure of the Reef-Building Coral, Porites astreoides. PLoS ONE 7(9): e44246. doi:10.1371/journal.pone.0044246

Abstract: With the continued and unprecedented decline of coral reefs worldwide, evaluating the factors that contribute to coral demise is of critical importance. As coral cover declines, macroalgae are becoming more common on tropical reefs. Interactions between these macroalgae and corals may alter the coral microbiome, which is thought to play an important role in colony health and survival. Together, such changes in benthic macroalgae and in the coral microbiome may result in a feedback mechanism that contributes to additional coral cover loss. To determine if macroalgae alter the coral microbiome, we conducted a field-based experiment in which the coral Porites astreoides was placed in competition with five species of macroalgae. Macroalgal contact increased variance in the coral-associated microbial community, and two algal species significantly altered microbial community composition. All macroalgae caused the disappearance of a γ-proteobacterium previously hypothesized to be an important mutualist of P. astreoides. Macroalgal contact also triggered: 1) increases or 2) decreases in microbial taxa already present in corals, 3) establishment of new taxa to the coral microbiome, and 4) vectoring and growth of microbial taxa from the macroalgae to the coral. Furthermore, macroalgal competition decreased coral growth rates by an average of 36.8%. Overall, this study found that competition between corals and certain species of macroalgae leads to an altered coral microbiome, providing a potential mechanism by which macroalgae-coral interactions reduce coral health and lead to coral loss on impacted reefs.

Recurrent Disturbances and the Degradation of Hard Coral Communities in Taiwan

Citation Information: Kuo C-Y, Yuen YS, Meng P-J, Ho P-H, Wang J-T, et al. (2012) Recurrent Disturbances and the Degradation of Hard Coral Communities in Taiwan. PLoS ONE 7(8): e44364. doi:10.1371/journal.pone.0044364

Abstract: Recurrent disturbances can have a critical effect on the structure and function of coral reef communities. In this study, long-term changes were examined in the hard coral community at Wanlitung, in southern Taiwan, between 1985 and 2010. In this 26 year interval, the reef has experienced repeated disturbances that include six typhoons and two coral-bleaching events. The frequency of disturbance has meant that species susceptible to disturbance, such as those in the genus Acropora and Montipora have almost disappeared from the reef. Indeed, almost all hard coral species have declined in abundance, with the result that total hard coral cover in 2010 (17.7%) was less than half what it was in 1985 (47.5%). In addition, macro-algal cover has increased from 11.3% in 2003 to 28.5% in 2010. The frequency of disturbance combined with possible chronic influence of a growing human population mean that a diverse reef assemblage is unlikely to persist on this reef into the future.

Toxicity of Nano-Zero Valent Iron to Freshwater and Marine Organisms

Citation Information: Keller AA, Garner K, Miller RJ, Lenihan HS (2012) Toxicity of Nano-Zero Valent Iron to Freshwater and Marine Organisms. PLoS ONE 7(8): e43983. doi:10.1371/journal.pone.0043983

Abstract: We tested whether three commercial forms (uncoated, organic coating, and iron oxide coating) of nano zero-valent iron (nZVI) are toxic to freshwater and marine organisms, specifically three species of marine phytoplankton, one species of freshwater phytoplankton, and a freshwater zooplankton species (Daphnia magna), because these organisms may be exposed downstream of where nZVI is applied to remediate polluted soil. The aggregation and reactivity of the three types of nZVI varied considerably, which was reflected in their toxicity. Since levels of Fe2+ and Fe3+ increase as the nZVI react, we also evaluated their toxicity independently. All four phytoplankton species displayed decreasing population growth rates, and Daphnia magna showed increasing mortality, in response to increasing levels of nZVI, and to a lesser degree with increasing Fe2+ and Fe3+. All forms of nZVI aggregated in soil and water, especially in the presence of a high concentration of calcium ions in groundwater, thus reducing their transports through the environment. However, uncoated nZVI aggregated extremely rapidly, thus vastly reducing the probability of environmental transport and potential for toxicity. This information can be used to design a risk management strategy to arrest the transport of injected nZVI beyond the intended remediation area, by injecting inert calcium salts as a barrier to transport.

Scuba Diving and Marine Conservation: Collaboration at two Australian Subtropical Destinations

Citation Information: Tourism in Marine Environments, Volume 8, Numbers 1-2, 2012 , pp. 77-90 (14)

Authors: Hammerton, Zan; Dimmock, Kay; Hahn, Christine; Dalton, Steven J.; Smith, Stephen D.A.

Abstract: Divers are increasingly becoming involved in marine conservation, often doing so as part of their recreational activities. Two New South Wales (NSW) volunteer underwater conservation groups [Solitary Islands Underwater research Group Inc. (SURG) and Byron Underwater research Groups (BURG)] were studied to characterize members' motivations to assist with conservation in subtropical/temperate marine environments. The collaboration between private and government organizations at two dive destinations was explored to reveal implications towards marine conservation outcomes. Primary motivations to engage in marine conservation programs were a desire to contribute to environmental conservation and to increase personal knowledge and diving skill-base. The volunteer work of these two underwater research groups builds on existing monitoring programs within local marine protected areas with benefits possible through collaboration at each diving destination.

Eutrophication and environmental policy in the Mediterranean Sea: a review

Citation Information: Environmental Monitoring and Assessment; Volume 184, Number 8 (2012), 4931-4984

DOI: 10.1007/s10661-011-2313-2

Authors: Michael Karydis and Dimitra Kitsiou

Abstract: The Mediterranean Sea is a semienclosed basin connected with the open sea mainly through the Strait of Gibraltar. Due to the circulation pattern and the long residence time ranging between 80 and 100 years, the Mediterranean Sea is a sensitive environment to eutrophication pressures. The main body of water of the Mediterranean is characterized by very low nutrient concentrations, and therefore, the Mediterranean is classified among the most oligotrophic (very poor waters in nutrients) seas of the world’s oceans. However, some coastal areas, mainly in the northern part of the basin, receive excessive loads of nutrients from sewage effluents, river fluxes, aquaculture farms, fertilizers, and industrial facilities, showing intense eutrophic phenomena with many adverse effects for the marine ecosystem and humans. Various national and international authorities, in addition to monitoring, have taken legal and administrative measures to mitigate eutrophication trends in the area. The Mediterranean environment is a good paradigm of integration of extensive legal framework, scientific knowledge, and administrative practices. The Barcelona Convention, the Mediterranean Action Plan, and European Union Directives on water quality and coastal management, together with scientific information derived from international research programs in the Mediterranean, provide a sound background for practical actions in eutrophication problems. In the present work, the problem of coastal eutrophication in the Mediterranean is reviewed in connection with public policies of the Mediterranean States based on national and international legislation and scientific knowledge on Mediterranean oceanography—ecology and actions coordinated by international bodies. These common actions and practices on coastal management are also discussed in relation to the need for sustainable development and protection of the coastal zone in the Mediterranean Sea. 

Optimal Bioeconomic Multispecies Fisheries Management: A Baltic Sea Case Study

Citation Information: EMMI NIEMINEN, MARKO LINDROOS, and OUTI HEIKINHEIMO (2012) Optimal Bioeconomic Multispecies Fisheries Management: A Baltic Sea Case Study. Marine Resource Economics: June 2012, Vol. 27, No. 2, pp. 115-136.

Abstract: We assess cod, herring, and sprat fisheries in the Baltic Sea under different environmental conditions using a bioeconomic model with simple predation functions. We compare the status quo fishing policy to an optimal policy under two different salinity conditions, which have a link to climate change. The fishery of these species is not at the most profitable level. If the fishing mortalities are lower, economic return will be greater in the long run. A lower fishing mortality for cod, which allows time for individuals to grow and achieve a higher economic value and reproduction potential, would result in the recovery of the cod stock. Under a high salinity level, which leads to better conditions for cod recruitment, the cod stock has a better chance to recover even without a decrease in fishing mortality. Therefore, fishery management is even more important under conditions of low salinity, which are likely to prevail in the future due to changing climate.

Fishing, Finning and Tourism: Trends in Pacific Shark Conservation and Management

Citation Information: The International Journal of Marine and Coastal Law, Volume 27, Number 3, 2012 , pp. 597-621(25)

Author: Techera, Erika J.

Abstract: Sharks have a key position in the ocean food chain and their removal could have far-reaching implications beyond the species themselves. Yet since the 1980s the harvesting of sharks, primarily for their fins, and their extraction as bycatch have resulted in a rapid decline in numbers. It is against this backdrop that the Pacific is leading the way in legal developments for shark conservation: from the US shark conservation law, and finning bans in Hawai'i, the Commonwealth of the Northern Mariana Islands and Guam, to the declaration of Palau's shark sanctuary. These national initiatives have been complemented by regional action, including the adoption of a Regional Plan of Action for sharks by the Pacific nations. This article examines the legal developments and the emerging leadership role the region is taking. The lessons that they offer are explored, as well as some of the remaining challenges.

For the turtles’ sake: Miracles, the third sector and hegemony on the coast of Oaxaca (Mexico)

Citation Information: Critique of Anthropology September 2012 vol. 32 no. 3 241-260

Author: Ricardo F. Macip

Abstract: Turtle fishing – which defined life and work, and the tempo and contours of the coast of Oaxaca – was halted by presidential decree in 1990. The industry’s workers converted from predators into guardians of nature under the stewardship of an emergent civil society that coordinated the efforts of environmental NGOs, the regulations of corresponding governmental agencies, and funding from private and public donors. Here I discuss the material and ideological transformation of the social relations of production in an ‘environmental’ class project. I argue an interpretation focused on the relation between coercion and consent in a hegemonic process of class rule.

Separability indexes and accuracy of Neuro-fuzzy classification in Geographical Information Systems for assessment of coastal environmental vulnerability

Citation Information: Ecological Informatics; Available online 4 September 2012; In Press, Accepted Manuscript

Authors: J. Moreno, T. Telfer, L.G. Ross

Abstract: The aim of this study was the development, evaluation and analysis of a Neuro-fuzzy classifier for a supervised and hard classification of coastal environmental vulnerability due to marine aquaculture using minimal training sets within a Geographic Information System (GIS). The neuro-fuzzy classification model NEFCLASS–J, was used to develop learning algorithms to create the structure (rule base) and the parameters (fuzzy sets) of a fuzzy classifier from a set of labeled data. The training sites were manually classified based on four categories of coastal environmental vulnerability through meetings and interviews with experts having field experience and specific knowledge of the environmental problems investigated. The inter-class separability estimations were performed on the training data set to assess the difficulty of the class separation problem under investigation. The two training data sets did not follow the assumptions of multivariate normality. For this reason Bhattacharyy and Jeffries-Matusita distances were used to estimate the probability of correct classification. Further evaluation and analysis of the quality of the classification achieved low values of quantity and allocation disagreement and a good overall accuracy. For each of the four classes the user and producer values for accuracy were between 77% and 100%.

In conclusion, the use of a neuro-fuzzy classifier for a supervised and hard classification of coastal environmental vulnerability demonstrated an ability to derive an accurate and reliable classification using a minimal number of training sets.

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