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Author

Greta S. Aeby

Bio: Greta S. Aeby is an academic researcher from Qatar University. The author has contributed to research in topics: Coral & Coral reef. The author has an hindex of 31, co-authored 82 publications receiving 3501 citations. Previous affiliations of Greta S. Aeby include University of Hawaii at Manoa & University of Hawaii.
Topics: Coral, Coral reef, Reef, Montipora, Porites


Papers
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Journal ArticleDOI
25 Jul 2008-Science
TL;DR: The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle has the highest proportion of species in all categories of elevated extinction risk.
Abstract: The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures.

1,272 citations

Journal ArticleDOI
TL;DR: This work provides a framework to systematically describe and name diseases in corals involving 4 steps: naming the disease, describing the lesion, formulating a morphologic diagnosis and (4) formulating an etiologic diagnosis.
Abstract: Many coral diseases are characterized based on gross descriptions and, given the lack or difficulty of applying existing laboratory tools to understanding causes of coral diseases, most new diseases will continued to be described based on appearance in the field. Unfortunately, many existing descriptions of coral disease are ambiguous or open to subjective interpretation, making comparisons between oceans problematic. One reason for this is that the process of describing lesions is often confused with that of assigning causality for the lesion. However, causality is usually something not obtained in the field and requires additional laboratory tests. Because a concise and objective morphologic description provides the foundation for a case definition of any disease, there is a need for a consistent and standardized process to describe lesions of corals that focuses on morphology. We provide a framework to systematically describe and name diseases in corals involving 4 steps: (1) naming the disease, (2) describing the lesion, (3) formulating a morphologic diagnosis and (4) formulating an etiologic diagnosis. This process focuses field investigators on describing what they see and separates the process of describing a lesion from that of inferring causality, the latter being more appropriately done using laboratory techniques.

154 citations

Journal ArticleDOI
TL;DR: Both corals that were protected from and those that were exposed to fish predation contracted the disease, and either direct oral transmission of the pathogen from colony to colony and/or indirect fecal transmission could be occurring.
Abstract: Black-band disease affects many species of tropical reef-building corals, but it is unclear what factors contribute to the disease-susceptibility of individual corals or how the disease is transmitted between colonies. Studies have suggested that the ability of black-band disease to infect coral is enhanced by different stressors. We examined the effect of both water temperature and mechanical injury on the ability of this disease to infect the reef coral Montastraea faveolata, and investigated the possibility of an interaction between the 2 stressors. Under laboratory conditions, Phormidium corallyticum was able to successfully invade all injured fragments but no uninjured fragments of M. faveolata, irrespective of temperature regime. We also determined whether the local coral-feeding butterflyfish Chaetodon capistratus was involved in the inter-colony transfer of black-band disease. In aquaria, the presence of C. capistratus increased the rate at which the disease spread from infected to non-infected fragments of M. faveolata. Both corals that were protected from and those that were exposed to fish predation contracted the disease. Hence, either direct oral transmission of the pathogen from colony to colony and/or indirect fecal transmission could be occurring. Variables such as potential stressors and/or disease vectors on a reef could contribute to the patterns of black-band disease observed in the field.

142 citations

Journal ArticleDOI
08 Oct 2012-PLOS ONE
TL;DR: This investigation of Montipora white syndrome recognizes V. owensii OCN002 as the first bacterial coral pathogen identified from Hawaii’s reefs and expands the range of bacteria known to cause disease in corals.
Abstract: Incidences of coral disease in the Indo-Pacific are increasing at an alarming rate In particular, Montipora white syndrome, a tissue-loss disease found on corals throughout the Hawaiian archipelago, has the potential to degrade Hawaii’s reefs To identify the etiologic agent of Montipora white syndrome, bacteria were isolated from a diseased fragment of Montipora capitata and used in a screen for virulent strains A single isolate, designated strain OCN002, recreated disease signs in 53% of coral fragments in laboratory infection trials when added to a final concentration of 107 cells/ml of seawater In addition to displaying similar signs of disease, diseased coral fragments from the field and those from infection trials both had a dramatic increase in the abundance of associated culturable bacteria, with those of the genus Vibiro well represented Bacteria isolated from diseased fragments used in infection trails were shown to be descendants of the original OCN002 inocula based on both the presence of a plasmid introduced to genetically tag the strain and the sequence of a region of the OCN002 genome In contrast, OCN002 was not re-isolated from fragments that were exposed to the strain but did not develop tissue loss Sequencing of the rrsH gene, metabolic characterization, as well as multilocus sequence analysis indicated that OCN002 is a strain of the recently described species Vibrio owensii This investigation of Montipora white syndrome recognizes V owensii OCN002 as the first bacterial coral pathogen identified from Hawaii’s reefs and expands the range of bacteria known to cause disease in corals

105 citations

Journal ArticleDOI
TL;DR: Vibrio coralliilyticus strain OCN008 is described, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coralmontipora capitata in Kāne‘ohe Bay, Hawai‘i.
Abstract: Identification of a pathogen is a critical first step in the epidemiology and subsequent management of a disease. A limited number of pathogens have been identified for diseases contributing to the global decline of coral populations. Here we describe Vibrio coralliilyticus strain OCN008, which induces acute Montipora white syndrome (aMWS), a tissue loss disease responsible for substantial mortality of the coral Montipora capitata in Kāne'ohe Bay, Hawai'i. OCN008 was grown in pure culture, recreated signs of disease in experimentally infected corals, and could be recovered after infection. In addition, strains similar to OCN008 were isolated from diseased coral from the field but not from healthy M. capitata. OCN008 repeatedly induced the loss of healthy M. capitata tissue from fragments under laboratory conditions with a minimum infectious dose of between 10(7) and 10(8) CFU/ml of water. In contrast, Porites compressa was not infected by OCN008, indicating the host specificity of the pathogen. A decrease in water temperature from 27 to 23°C affected the time to disease onset, but the risk of infection was not significantly reduced. Temperature-dependent bleaching, which has been observed with the V. coralliilyticus type strain BAA-450, was not observed during infection with OCN008. A comparison of the OCN008 genome to the genomes of pathogenic V. coralliilyticus strains BAA-450 and P1 revealed similar virulence-associated genes and quorum-sensing systems. Despite this genetic similarity, infections of M. capitata by OCN008 do not follow the paradigm for V. coralliilyticus infections established by the type strain.

101 citations


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Journal ArticleDOI
19 Aug 2011-Science
TL;DR: A meta-analysis shows that species are shifting their distributions in response to climate change at an accelerating rate, and that the range shift of each species depends on multiple internal species traits and external drivers of change.
Abstract: The distributions of many terrestrial organisms are currently shifting in latitude or elevation in response to changing climate Using a meta-analysis, we estimated that the distributions of species have recently shifted to higher elevations at a median rate of 110 meters per decade, and to higher latitudes at a median rate of 169 kilometers per decade These rates are approximately two and three times faster than previously reported The distances moved by species are greatest in studies showing the highest levels of warming, with average latitudinal shifts being generally sufficient to track temperature changes However, individual species vary greatly in their rates of change, suggesting that the range shift of each species depends on multiple internal species traits and external drivers of change Rapid average shifts derive from a wide diversity of responses by individual species

3,986 citations

Journal ArticleDOI
TL;DR: In this paper, the main ecological services across a variety of estuarine and coastal ecosystems (ECEs) including marshes, mangroves, nearshore coral reefs, seagrass beds, and sand beaches and dunes are reviewed.
Abstract: The global decline in estuarine and coastal ecosystems (ECEs) is affecting a number of critical benefits, or ecosystem services. We review the main ecological services across a variety of ECEs, including marshes, mangroves, nearshore coral reefs, seagrass beds, and sand beaches and dunes. Where possible, we indicate estimates of the key economic values arising from these services, and discuss how the natural variability of ECEs impacts their benefits, the synergistic relationships of ECEs across seascapes, and management implications. Although reliable valuation estimates are beginning to emerge for the key services of some ECEs, such as coral reefs, salt marshes, and mangroves, many of the important benefits of seagrass beds and sand dunes and beaches have not been assessed properly. Even for coral reefs, marshes, and mangroves, important ecological services have yet to be valued reliably, such as cross-ecosystem nutrient transfer (coral reefs), erosion control (marshes), and pollution control (mangroves). An important issue for valuing certain ECE services, such as coastal protection and habitat-fishery linkages, is that the ecological functions underlying these services vary spatially and temporally. Allowing for the connectivity between ECE habitats also may have important implications for assessing the ecological functions underlying key ecosystems services, such coastal protection, control of erosion, and habitat-fishery linkages. Finally, we conclude by suggesting an action plan for protecting and/or enhancing the immediate and longer-term values of ECE services. Because the connectivity of ECEs across land-sea gradients also influences the provision of certain ecosystem services, management of the entire seascape will be necessary to preserve such synergistic effects. Other key elements of an action plan include further ecological and economic collaborative research on valuing ECE services, improving institutional and legal frameworks for management, controlling and regulating destructive economic activities, and developing ecological restoration options.

3,750 citations

Journal ArticleDOI
30 May 2014-Science
TL;DR: The biodiversity of eukaryote species and their extinction rates, distributions, and protection is reviewed, and what the future rates of species extinction will be, how well protected areas will slow extinction Rates, and how the remaining gaps in knowledge might be filled are reviewed.
Abstract: Background A principal function of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is to “perform regular and timely assessments of knowledge on biodiversity.” In December 2013, its second plenary session approved a program to begin a global assessment in 2015. The Convention on Biological Diversity (CBD) and five other biodiversity-related conventions have adopted IPBES as their science-policy interface, so these assessments will be important in evaluating progress toward the CBD’s Aichi Targets of the Strategic Plan for Biodiversity 2011–2020. As a contribution toward such assessment, we review the biodiversity of eukaryote species and their extinction rates, distributions, and protection. We document what we know, how it likely differs from what we do not, and how these differences affect biodiversity statistics. Interestingly, several targets explicitly mention “known species”—a strong, if implicit, statement of incomplete knowledge. We start by asking how many species are known and how many remain undescribed. We then consider by how much human actions inflate extinction rates. Much depends on where species are, because different biomes contain different numbers of species of different susceptibilities. Biomes also suffer different levels of damage and have unequal levels of protection. How extinction rates will change depends on how and where threats expand and whether greater protection counters them. Different visualizations of species biodiversity. ( A ) The distributions of 9927 bird species. ( B ) The 4964 species with smaller than the median geographical range size. ( C ) The 1308 species assessed as threatened with a high risk of extinction by BirdLife International for the Red List of Threatened Species of the International Union for Conservation of Nature. ( D ) The 1080 threatened species with less than the median range size. (D) provides a strong geographical focus on where local conservation actions can have the greatest global impact. Additional biodiversity maps are available at www.biodiversitymapping.org. Advances Recent studies have clarified where the most vulnerable species live, where and how humanity changes the planet, and how this drives extinctions. These data are increasingly accessible, bringing greater transparency to science and governance. Taxonomic catalogs of plants, terrestrial vertebrates, freshwater fish, and some marine taxa are sufficient to assess their status and the limitations of our knowledge. Most species are undescribed, however. The species we know best have large geographical ranges and are often common within them. Most known species have small ranges, however, and such species are typically newer discoveries. The numbers of known species with very small ranges are increasing quickly, even in well-known taxa. They are geographically concentrated and are disproportionately likely to be threatened or already extinct. We expect unknown species to share these characteristics. Current rates of extinction are about 1000 times the background rate of extinction. These are higher than previously estimated and likely still underestimated. Future rates will depend on many factors and are poised to increase. Finally, although there has been rapid progress in developing protected areas, such efforts are not ecologically representative, nor do they optimally protect biodiversity. Outlook Progress on assessing biodiversity will emerge from continued expansion of the many recently created online databases, combining them with new global data sources on changing land and ocean use and with increasingly crowdsourced data on species’ distributions. Examples of practical conservation that follow from using combined data in Colombia and Brazil can be found at www.savingspecies.org and www.youtube.com/watch?v=R3zjeJW2NVk.

2,360 citations

Journal ArticleDOI
TL;DR: In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wide-ranging biological effects.
Abstract: In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wideranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together with local climate-driven invasion and extinction, these processes result in altered community structure and diversity, including possible emergence of novel ecosystems. Impacts are particularly striking for the poles and the tropics, because of the sensitivity of polar ecosystems to sea-ice retreat and poleward species migrations as well as the sensitivity of coral-algal symbiosis to minor increases in temperature. Midlatitude upwelling systems, like the California Current, exhibit strong linkages between climate and species distributions, phenology, and demography. Aggregated effects may modify energy and material flows as well as biogeochemical cycles, eventually impacting the overall ecosystem functioning and services upon which people and societies depend.

2,136 citations

Journal ArticleDOI
21 Jan 2014-eLife
TL;DR: In this article, the authors present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes (sharks, rays, and chimaeras).
Abstract: The rapid expansion of human activities threatens ocean-wide biodiversity. Numerous marine animal populations have declined, yet it remains unclear whether these trends are symptomatic of a chronic accumulation of global marine extinction risk. We present the first systematic analysis of threat for a globally distributed lineage of 1,041 chondrichthyan fishes—sharks, rays, and chimaeras. We estimate that one-quarter are threatened according to IUCN Red List criteria due to overfishing (targeted and incidental). Large-bodied, shallow-water species are at greatest risk and five out of the seven most threatened families are rays. Overall chondrichthyan extinction risk is substantially higher than for most other vertebrates, and only one-third of species are considered safe. Population depletion has occurred throughout the world's ice-free waters, but is particularly prevalent in the Indo-Pacific Biodiversity Triangle and Mediterranean Sea. Improved management of fisheries and trade is urgently needed to avoid extinctions and promote population recovery.

1,467 citations