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Edmunds PJ. Decadal-scale time series highlight the role of chronic disturbances in driving ecosystem collapse in the Anthropocene. Ecology 2024; 105:e4360. [PMID: 38899537 DOI: 10.1002/ecy.4360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/12/2024] [Accepted: 04/09/2024] [Indexed: 06/21/2024]
Abstract
Biome degradation characterizes the Anthropocene Epoch, and modern ecology is deeply involved with describing the changes underway. Most research has focused on the role of acute disturbances in causing conspicuous changes in ecosystem structure, which leads to an underappreciation of the chronic effects causing large changes through the cumulative effects of small perturbations over decades. Coral reefs epitomize this trend, because the changes in community structure are profound, yet the data to quantify these effects are usually insufficient to evaluate the relative roles of different disturbance types. Here, four decades of surveys from two coral reefs (9 and 14 m depth) off St. John, US Virgin Islands, are used to quantify the associations of acute and chronic events with the changes in benthic community structure. These reefs profoundly changed over 36 years, with coral death altering species assemblages to depress abundances of the ecologically important coral Orbicella spp. and elevating the coverage of macroalgae and crustose coralline algae/turf/bare space (CTB). Linear mixed models revealed the prominent role of chronic variation in temperature in accounting for changes in coverage of corals, macroalgae, and CTB, with rising temperature associated with increases in coral cover on the deep reef, and declines on the shallow reef. Hurricanes were also associated with declines in coral cover on the shallow reef, and increases on the deep reef. Multivariate analyses revealed strong associations between community structure and temperature, but weaker associations with hurricanes, bleaching, and diseases. These results highlight the overwhelming importance of chronically increasing temperature in altering the benthic community structure of Caribbean reefs.
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Affiliation(s)
- Peter J Edmunds
- Department of Biology, California State University, Northridge, California, USA
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2
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Repetto MF, Torchin ME, Ruiz GM, Schlöder C, Freestone AL. Biogeographic and seasonal differences in consumer pressure underlie strong predation in the tropics. Proc Biol Sci 2024; 291:20240868. [PMID: 38955327 DOI: 10.1098/rspb.2024.0868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 06/03/2024] [Indexed: 07/04/2024] Open
Abstract
Biotic interactions play a critical role in shaping patterns of global biodiversity. While several macroecological studies provide evidence for stronger predation in tropical regions compared with higher latitudes, results are variable even within the tropics, and the drivers of this variability are not well understood. We conducted two complementary standardized experiments on communities of sessile marine invertebrate prey and their associated predators to test for spatial and seasonal differences in predation across the tropical Atlantic and Pacific coastlines of Panama. We further tested the prediction that higher predator diversity contributes to stronger impacts of predation, using both direct observations of predators and data from extensive reef surveys. Our results revealed substantially higher predation rates and stronger effects of predators on prey in the Pacific than in the Atlantic, demonstrating striking variation within tropical regions. While regional predator diversity was high in the Atlantic, functional diversity at local scales was markedly low. Peak predation strength in the Pacific occurred during the wet, non-upwelling season when ocean temperatures were warmer and predator communities were more functionally diverse. Our results highlight the importance of regional biotic and abiotic drivers that shape interaction strength and the maintenance of tropical communities, which are experiencing rapid environmental change.
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Affiliation(s)
- Michele F Repetto
- Department of Biology, Temple University, Philadelphia, PA 19122, USA
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama
- Smithsonian Environmental Research Center, Edgewater, MD 21037-0028, USA
| | - Mark E Torchin
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama
| | - Gregory M Ruiz
- Smithsonian Environmental Research Center, Edgewater, MD 21037-0028, USA
| | - Carmen Schlöder
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama
| | - Amy L Freestone
- Department of Biology, Temple University, Philadelphia, PA 19122, USA
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancon, Panama
- Smithsonian Environmental Research Center, Edgewater, MD 21037-0028, USA
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3
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Young HS, McCauley FO, Micheli F, Dunbar RB, McCauley DJ. Shortened food chain length in a fished versus unfished coral reef. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2024; 34:e3002. [PMID: 38840322 DOI: 10.1002/eap.3002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 02/23/2024] [Accepted: 04/09/2024] [Indexed: 06/07/2024]
Abstract
Direct exploitation through fishing is driving dramatic declines of wildlife populations in ocean environments, particularly for predatory and large-bodied taxa. Despite wide recognition of this pattern and well-established consequences of such trophic downgrading on ecosystem function, there have been few empirical studies examining the effects of fishing on whole system trophic architecture. Understanding these kinds of structural impacts is especially important in coral reef ecosystems-often heavily fished and facing multiple stressors. Given the often high dietary flexibility and numerous functional redundancies in diverse ecosystems such as coral reefs, it is important to establish whether web architecture is strongly impacted by fishing pressure or whether it might be resilient, at least to moderate-intensity pressure. To examine this question, we used a combination of bulk and compound-specific stable isotope analyses measured across a range of predatory and low-trophic-level consumers between two coral reef ecosystems that differed with respect to fishing pressure but otherwise remained largely similar. We found that even in a high-diversity system with relatively modest fishing pressure, there were strong reductions in the trophic position (TP) of the three highest TP consumers examined in the fished system but no effects on the TP of lower-level consumers. We saw no evidence that this shortening of the affected food webs was being driven by changes in basal resource consumption, for example, through changes in the spatial location of foraging by consumers. Instead, this likely reflected internal changes in food web architecture, suggesting that even in diverse systems and with relatively modest pressure, human harvest causes significant compressions in food chain length. This observed shortening of these food webs may have many important emergent ecological consequences for the functioning of ecosystems impacted by fishing or hunting. Such important structural shifts may be widespread but unnoticed by traditional surveys. This insight may also be useful for applied ecosystem managers grappling with choices about the relative importance of protection for remote and pristine areas and the value of strict no-take areas to protect not just the raw constituents of systems affected by fishing and hunting but also the health and functionality of whole systems.
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Affiliation(s)
- Hillary S Young
- Department of Ecology, Evolution and Marine Biology, UC Santa Barbara, Santa Barbara, California, USA
| | | | - Fiorenza Micheli
- Oceans Department, Hopkins Marine Station, and Stanford Center for Ocean Solutions, Stanford University, Pacific Grove, California, USA
| | - Robert B Dunbar
- Oceans Department and Earth Systems Science, Stanford University, Pacific Grove, California, USA
| | - Douglas J McCauley
- Department of Ecology, Evolution and Marine Biology, UC Santa Barbara, Santa Barbara, California, USA
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4
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Muruga P, Siqueira AC, Bellwood DR. Meta-analysis reveals weak associations between reef fishes and corals. Nat Ecol Evol 2024; 8:676-685. [PMID: 38374185 DOI: 10.1038/s41559-024-02334-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 01/18/2024] [Indexed: 02/21/2024]
Abstract
Habitat associations underpin species ecologies in high-diversity systems. Within tropical, shallow water coral reefs, the relationship between fishes and corals is arguably the most iconic and highly scrutinized. A strong relationship between fishes and reef-building hard corals is often assumed, a belief supported by studies that document the decline of reef fishes following coral loss. However, the extent of this relationship is often unclear, as evidenced by conflicting reports. Here we assess the strength of this ecological association by relying on literature that has surveyed both fishes and corals synchronously. We quantitatively synthesize 723 bivariate correlation coefficients (from 66 papers), published over 38 years, that relate fish metrics (abundance, biomass and species richness) with the percentage of hard coral cover. Remarkably, despite extensive variation, the pattern of association on a global scale reveals a predominantly positive, albeit weak (|r| < 0.4), correlation. Even for commonly hypothesized drivers of fish-coral associations, fish family and trophic group, associations were consistently weak. These findings question our assumptions regarding the strength and ubiquity of fish-coral associations, and caution against assuming a direct and omnipresent relationship between these two iconic animal groups.
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Affiliation(s)
- Pooventhran Muruga
- Research Hub for Coral Reef Ecosystem Functions, College of Science and Engineering, James Cook University, Townsville, Queensland, Australia.
| | - Alexandre C Siqueira
- Research Hub for Coral Reef Ecosystem Functions, College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
| | - David R Bellwood
- Research Hub for Coral Reef Ecosystem Functions, College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
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McDevitt-Irwin JM, McCauley DJ, Brumbaugh DR, Elmer F, Ferretti F, White TD, Wible JG, Micheli F. Dynamic interplay: disentangling the temporal variability of fish effects on coral recruitment. Sci Rep 2023; 13:20971. [PMID: 38017077 PMCID: PMC10684556 DOI: 10.1038/s41598-023-47758-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 11/17/2023] [Indexed: 11/30/2023] Open
Abstract
Ecosystems around the world are continuously undergoing recovery from anthropogenic disturbances like climate change, overexploitation, and habitat destruction. Coral reefs are a prime example of a threatened ecosystem and coral recruitment is a critical component of reef recovery from disturbances. Reef fishes structure this recruitment by directly consuming macroalgae and coral recruits or by indirectly altering the substrate to facilitate coral settlement (e.g., grazing scars). However, how these direct and indirect mechanisms vary through time remains largely unknown. Here, we quantified coral recruitment on settlement tiles with divots that mimic grazing scars and caging treatments to exclude or allow fish feeding over 3 years at Palmyra Atoll in the Pacific Ocean. We found that the positive and negative effects of fishes on coral recruitment varies through time. After 3 years, both grazing scars and fish grazing no longer predicted coral recruitment, suggesting that the role of fishes decreases over time. Our results emphasize that reef fish populations are important in promoting initial coral recovery after disturbances. However, over time, factors like the environment may become more important. Future work should continue to explore how the strength and direction of top-down control by consumers varies through time across multiple ecosystems.
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Affiliation(s)
- Jamie M McDevitt-Irwin
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA.
- Marine Science Institute, University of California, Santa Barbara, CA, USA.
| | - Douglas J McCauley
- Marine Science Institute, University of California, Santa Barbara, CA, USA
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA, USA
| | - Daniel R Brumbaugh
- Elkhorn Slough National Estuarine Research Reserve, Watsonville, CA, USA
- Environmental Studies, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Franziska Elmer
- School for Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
- Center for Marine Resource Studies, School for Field Studies, Cockburn Harbour, South Caicos, Turks and Caicos Islands
| | - Francesco Ferretti
- Fish and Wildlife Conservation Department, Virginia Tech, Blacksburg, VA, USA
| | - Timothy D White
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Joseph G Wible
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
| | - Fiorenza Micheli
- Hopkins Marine Station, Stanford University, Pacific Grove, CA, USA
- Center for Ocean Solutions, Stanford University, Pacific Grove, CA, USA
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Caballero-Aragón H, Perera-Valderrama S, Cobián-Rojas D, Hernández Gonzalez Z, González Méndez J, De la Guardia E. A decade of study on the condition of western Cuban coral reefs, with low human impact. PeerJ 2023; 11:e15953. [PMID: 37667748 PMCID: PMC10475277 DOI: 10.7717/peerj.15953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 08/01/2023] [Indexed: 09/06/2023] Open
Abstract
Background The long-time study of coral reefs with low human impacts can provide information on the effects of regional pressures like climate change, and is an opportunity to document how these pressures are reflected in coral communities. An example of minimal local anthropogenic impacts are the Guanahacabibes coral reefs, located in the westernmost region of Cuba. The objectives of this study were: to evaluate the temporal variability of six benthic biological indicators of coral reefs, and to explore the possible relationship between predictive abiotic variables and biological response variables. Methods Four coral reef sites were sampled between 2008 and 2017, to analyze biological indicators (living coral cover, fleshy algae index, coral species richness, coral species abundance, coral trait groups species abundance, Functional Reef Index). Seven abiotic variables (wave exposure, sea surface temperature, degree heating week, chlorophyll-a concentration, particulate organic carbon, photosynthetically available radiation, and the diffuse attenuation coefficient) were compiled between 2007 and 2016, from remote sensing datasets, to analyze their relationship with the biological indicators. Permanova statistical analysis was used to evaluate trends in biological variables between sites and years, and Routine Analysis Based on Linear Distances (DISTLM) was used to explore some dependencies between biotic and abiotic variables. Results We found significant variability in the temporal analysis, with a decrease in living coral cover, a decline in the predominance of the branching and massive framework reef-building species, a decline in Orbicella species abundance, and an increase in the fleshy algae index. Some abiotic variables (average of degree heating weeks, standard deviation of the diffuse attenuation coefficient, average of the sea surface temperature, among others) significantly explained the variability of biological indicators; however, determination coefficients were low. Conclusions Certain decrease in the functionality of the coral reef was appreciated, taking into account the predominance of secondary and nom-massive framework reef-building species in the last years. A weak association between abiotic and biological variables was found in the temporal analysis. The current scenario of the condition of the coral reefs seems to be regulated by the global effects of climate change, weakly associated effects, and in longer terms.
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Binder BM, Rieucau G, Locascio JV, Taylor JC, Boswell KM. Active acoustic surveys reveal coastal fish community resistance to an environmental perturbation in South Florida. PeerJ 2023; 11:e14888. [PMID: 37131991 PMCID: PMC10149053 DOI: 10.7717/peerj.14888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 01/22/2023] [Indexed: 05/04/2023] Open
Abstract
Coastal fish communities are under increasing levels of stress associated with climate variation and anthropogenic activities. However, the high degree of behavioral plasticity of many species within these communities allow them to cope with altered environmental conditions to some extent. Here, we combine meteorological information, data from hydroacoustic surveys, and recordings of goliath grouper sound production to examine the response of coastal fish communities to heavy rainfall events in South Florida, USA, that resulted in the release of excess storm water into surrounding estuaries and coastal waters. We observed a nearly 12,000% increase in water column acoustic backscatter following a heavy rainfall event of September 16th, 2015. Interestingly, estimates of school backscatter, a proxy for biomass, increased by 172% with the onset of the perturbation. Schooling fish density also increased by 182%, as did acoustically derived estimates of mean schooling fish length (21%). Following the perturbed period, school backscatter decreased by 406%, along with schooling density (272%), and mean schooling fish length (35%). Hydrophone and hydroacoustic data also revealed that goliath grouper (Epinephelus itajara) spawning aggregations were persistent in the region throughout the duration of the study and continued to exhibit courtship behavior during the perturbed period. Our observations demonstrate the high level of resistance common in coastal species but raises new questions regarding the threshold at which fish communities and reproductive activities are disrupted. As coastal land use continues to increase, and the effects of global climate change become more pronounced, more Before-After Control Impact (BACI) studies will provide improved insight into the overall response of nearshore communities to future perturbations and the cumulative effect of repeated perturbations over extended periods.
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Affiliation(s)
- Benjamin M. Binder
- Department of Biology / Marine Sciences Program / Florida International University, Florida International University, North Miami, FL, United States of America
| | - Guillaume Rieucau
- Louisiana Universities Marine Consortium, Chauvin, LA, United States of America
| | | | - J. Christopher Taylor
- National Ocean Service, National Oceanic and Atmospheric Administration, Beaufort, NC, United States of America
| | - Kevin M. Boswell
- Department of Biology, Marine Sciences Program, Florida International University, North Miami, FL, United States of America
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8
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Nguyen KAT, Jolly CM, Nguelifack BM, Nguyen TAT. The Use of a Production Function to Evaluate Caribbean Ocean Health Conflicts and Economic Development: Policy Implications. ENVIRONMENTAL MANAGEMENT 2022; 70:808-826. [PMID: 36028629 DOI: 10.1007/s00267-022-01696-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
Central American and Caribbean (CAC) countries enjoy diverse marine environments. The oceans that enclose these coastlines contribute significantly to their economic growth. Industrial expansion and tourism place pressure on the marine ecosystems causing a decline in ocean health. To evaluate the cause of ocean health changes we investigated the factors influencing CAC ocean health using a health production function. Using Rank-Based Regression and the set of extractive, cultural and human well-being and services goals measuring Ocean Health Index (OHI), data from the World Bank, and the Human Development Index we developed a production function for CAC countries ocean health. Results show that all regional OHI scores, but Tourism and Recreation, the main income earning industry for most of the CAC countries, are less than the global score with four of the goals less than 40. The production function shows that all the goals, but the biodiversity sub-goal species, positively influencing OHI. Two climatic related variables, Nitrous Oxide and Carbon Dioxide negatively influenced OHI. The results are important to policy makers as they decide on the need to make greater effort towards improving sustainable contribution of CAC ocean resources to the blue economy.
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Affiliation(s)
| | - Curtis M Jolly
- Department of Agricultural Economics, College of Agriculture, Auburn University, Alabama Agricultural Experiment Station, Auburn, 36849, AL, USA.
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9
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Alves C, Valdivia A, Aronson RB, Bood N, Castillo KD, Cox C, Fieseler C, Locklear Z, McField M, Mudge L, Umbanhowar J, Bruno JF. Twenty years of change in benthic communities across the Belizean Barrier Reef. PLoS One 2022; 17:e0249155. [PMID: 35041688 PMCID: PMC8765652 DOI: 10.1371/journal.pone.0249155] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 11/26/2021] [Indexed: 11/23/2022] Open
Abstract
Disease, storms, ocean warming, and pollution have caused the mass mortality of reef-building corals across the Caribbean over the last four decades. Subsequently, stony corals have been replaced by macroalgae, bacterial mats, and invertebrates including soft corals and sponges, causing changes to the functioning of Caribbean reef ecosystems. Here we describe changes in the absolute cover of benthic reef taxa, including corals, gorgonians, sponges, and algae, at 15 fore-reef sites (12-15m depth) across the Belizean Barrier Reef (BBR) from 1997 to 2016. We also tested whether Marine Protected Areas (MPAs), in which fishing was prohibited but likely still occurred, mitigated these changes. Additionally, we determined whether ocean-temperature anomalies (measured via satellite) or local human impacts (estimated using the Human Influence Index, HII) were related to changes in benthic community structure. We observed a reduction in the cover of reef-building corals, including the long-lived, massive corals Orbicella spp. (from 13 to 2%), and an increase in fleshy and corticated macroalgae across most sites. These and other changes to the benthic communities were unaffected by local protection. The covers of hard-coral taxa, including Acropora spp., Montastraea cavernosa, Orbicella spp., and Porites spp., were negatively related to the frequency of ocean-temperature anomalies. Only gorgonian cover was related, negatively, to our metric of the magnitude of local impacts (HII). Our results suggest that benthic communities along the BBR have experienced disturbances that are beyond the capacity of the current management structure to mitigate. We recommend that managers devote greater resources and capacity to enforcing and expanding existing marine protected areas and to mitigating local stressors, and most importantly, that government, industry, and the public act immediately to reduce global carbon emissions.
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Affiliation(s)
- Catherine Alves
- Environment, Ecology, and Energy Program, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- ECS Federal, Inc., in support of Northeast Fisheries Science Center, Social Science Branch, National Oceanic and Atmospheric Administration, Narragansett, RI, United States of America
| | | | - Richard B. Aronson
- Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology, Melbourne, Florida, United States of America
| | - Nadia Bood
- World Wildlife Fund Mesoamerica, Belize Field Programme Office, Belize City, Belize, Central America
| | - Karl D. Castillo
- Department of Marine Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Courtney Cox
- Rare, Arlington, Virginia, United States of America
| | - Clare Fieseler
- Science, Technology, and International Affairs Program, Georgetown University, Washington, District of Columbia, United States of America
| | - Zachary Locklear
- Green Bay Wildlife Conservation Office, United States Fish and Wildlife Service, New Franken, Wisconsin, United States of America
| | - Melanie McField
- Healthy Reefs for Healthy People Initiative, Smithsonian Institution, Fort Pierce, FL, United States of America
| | - Laura Mudge
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Integral Consulting Inc., Annapolis, Maryland, United States of America
| | - James Umbanhowar
- Environment, Ecology, and Energy Program, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - John F. Bruno
- Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
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Linardich C, Brookson CB, Green SJ. Trait-based vulnerability reveals hotspots of potential impact for a global marine invader. GLOBAL CHANGE BIOLOGY 2021; 27:4322-4338. [PMID: 34091996 DOI: 10.1111/gcb.15732] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 05/13/2021] [Indexed: 06/12/2023]
Abstract
Predation from the invasive Indo-Pacific lionfish is likely to amplify declines in marine fishes observed in multiple ocean basins. As the invasion intensifies and expands, there is an urgent need to identify species that are most at risk for extirpation-and possible extinction-from this added threat. To address this gap and inform conservation plans, we develop and apply a quantitative framework for classifying the relative vulnerability of fishes based on morphological and behavioural traits known to influence susceptibility to lionfish predation (e.g. body shape, water column position and aggregation behaviour), habitat overlap with lionfish, and degree of geographic range restriction. Applying the framework to fishes across the invaded Caribbean Sea and ahead of the invasion front in the southwestern Atlantic revealed the identity of at least 77 fishes with relatively small ranges that are likely to be most affected by lionfish predation. Trait-based vulnerability scores significantly predict the probability of fishes appearing within the diets of lionfish across the invaded region. Spatial richness analyses reveal hotspots of vulnerable species in the Bahamas, Belize and Curaçao. Crucially, our framework identifies 29 vulnerable fishes endemic to Brazil, which has not yet been colonized by lionfish. Of these, we suggest reefs around offshore island groups occupied by a dozen highly vulnerable and range-restricted species as priorities for intervention should lionfish spread to the region. Observations of the rate of lionfish spread across the invaded range suggest that an average of 5 years (with a median of nearly 2 years) elapses from first sighting to maximum observed densities. This lag may allow managers to mobilize plans to suppress lionfish ahead of an invasion front in priority locations. Our framework also provides a method for assessing the relative vulnerability of cryptobenthic and/or deep-reef fishes, for which population-monitoring data are limited.
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Affiliation(s)
- Christi Linardich
- International Union for Conservation of Nature Marine Biodiversity Unit, Department of Biological Sciences, Old Dominion University, Norfolk, VA, USA
| | - Cole B Brookson
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
| | - Stephanie J Green
- Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada
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11
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Cramer KL, Donovan MK, Jackson JBC, Greenstein BJ, Korpanty CA, Cook GM, Pandolfi JM. The transformation of Caribbean coral communities since humans. Ecol Evol 2021; 11:10098-10118. [PMID: 34367562 PMCID: PMC8328467 DOI: 10.1002/ece3.7808] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 05/24/2021] [Accepted: 06/03/2021] [Indexed: 11/06/2022] Open
Abstract
The mass die-off of Caribbean corals has transformed many of this region's reefs to macroalgal-dominated habitats since systematic monitoring began in the 1970s. Although attributed to a combination of local and global human stressors, the lack of long-term data on Caribbean reef coral communities has prevented a clear understanding of the causes and consequences of coral declines. We integrated paleoecological, historical, and modern survey data to track the occurrence of major coral species and life-history groups throughout the Caribbean from the prehuman period to the present. The regional loss of Acropora corals beginning by the 1960s from local human disturbances resulted in increases in the occurrence of formerly subdominant stress-tolerant and weedy scleractinian corals and the competitive hydrozoan Millepora beginning in the 1970s and 1980s. These transformations have resulted in the homogenization of coral communities within individual countries. However, increases in stress-tolerant and weedy corals have slowed or reversed since the 1980s and 1990s in tandem with intensified coral bleaching and disease. These patterns reveal the long history of increasingly stressful environmental conditions on Caribbean reefs that began with widespread local human disturbances and have recently culminated in the combined effects of local and global change.
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Affiliation(s)
- Katie L. Cramer
- Center for Biodiversity Outcomes and School of Life SciencesArizona State UniversityTempeAZUSA
| | - Mary K. Donovan
- Center for Global Discovery and Conservation Science and School of Geographical Sciences and Urban PlanningArizona State UniversityTempeAZUSA
| | - Jeremy B. C. Jackson
- Center for Biodiversity and Conservation and Department of PaleontologyAmerican Museum of Natural HistoryNew YorkNYUSA
| | | | - Chelsea A. Korpanty
- MARUM Center for Marine Environmental SciencesUniversity of BremenBremenGermany
| | - Geoffrey M. Cook
- Department of Biology and Health ScienceNew England CollegeHennikerNHUSA
| | - John M. Pandolfi
- Centre for Marine ScienceSchool of Biological Sciences and ARC Centre of Excellence for Coral Reef StudiesThe University of QueenslandSt LuciaQldAustralia
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12
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Blanar CA, Hornbeck JR, Kerstetter DW, Hirons AC. Stable isotopes and community surveys reveal differential use of artificial and natural reefs by South Florida fishes. Heliyon 2021; 7:e07413. [PMID: 34286118 PMCID: PMC8273218 DOI: 10.1016/j.heliyon.2021.e07413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/28/2021] [Accepted: 06/23/2021] [Indexed: 11/23/2022] Open
Abstract
Artificial reefs may enhance the biological production of reef-associated flora and fauna, but their trophic structure relative to that of natural reefs remains understudied. We assessed trophic relationships by 1) comparing reef fish communities and 2) comparing δ13C and δ15N in 43 fish species from both artificial reef sites and adjacent natural reef tracts in Broward County, Florida. We tested the effect of sampling location (artificial, first, and second reef), general feeding strategy (herbivore, omnivore, invertivore, and carnivore), phylogeny, and standard length on δ13C and δ15N. The reef fish communities of the artificial and natural reef tracts were significantly different; the artificial sites also exhibited more variability. For all samples, δ13C and δ15N ranged from -19.5 to -13.1‰ and 6.7–13.3‰, respectively. Significant effects were detected for both general feeding strategy and phylogeny. Significant differences were also seen in δ13C and δ15N profiles between artificial and natural reefs; however, these changes were primarily driven by differences in fish community structure, rather than by changes in the feeding strategy or trophic relationships of individual fish taxa. The trophic guild invertivore was the only group of fish to demonstrate significant isotopic differences between both reef tracts (inner and outer) and reef types (artificial and natural). The artificial reef may act more as a foraging corridor between the natural first and second reef tracts for omnivores and carnivores. If the function of artificial reefs is to provide additional foraging habitat for fishes, then perhaps more time is needed for the trophically important, infaunal invertebrate community to develop similarly to the natural reef environment.
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Affiliation(s)
- Christopher A Blanar
- Department of Biological Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 3301 College Avenue, Fort Lauderdale, FL 33314 USA
| | - Joseph R Hornbeck
- Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL 33004 USA
| | - David W Kerstetter
- Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL 33004 USA
| | - Amy C Hirons
- Department of Marine and Environmental Sciences, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, FL 33004 USA
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13
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Edmunds PJ. Recruitment hotspots and bottlenecks mediate the distribution of corals on a Caribbean reef. Biol Lett 2021; 17:20210149. [PMID: 34256581 PMCID: PMC8278041 DOI: 10.1098/rsbl.2021.0149] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/21/2021] [Indexed: 12/21/2022] Open
Abstract
Recruitment hotspots are locations where organisms are added to populations at high rates. On tropical reefs where coral abundance has declined, recruitment hotspots are important because they have the potential to promote population recovery. Around St. John, US Virgin Islands, coral recruitment at five sites revealed a hotspot that has persistent for 14 years. Recruitment created a hotspot in density of juvenile corals that was 600 m southeast of the recruitment hotspot. Neither hotspot led to increased coral cover, thus revealing the stringency of the demographic bottleneck impeding progression of recruits to adult sizes and preventing population growth. Recruitment hotspots in low-density coral populations are valuable targets for conservation and sources of corals for restoration.
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Affiliation(s)
- Peter J. Edmunds
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA 91330-8303, USA
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14
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Edmunds PJ, Didden C, Frank K. Over three decades, a classic winner starts to lose in a Caribbean coral community. Ecosphere 2021. [DOI: 10.1002/ecs2.3517] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Peter J. Edmunds
- Department of Biology California State University 18111 Nordhoff Street Northridge California91330USA
| | - Craig Didden
- Viewpoint School 23620 Mulholland Highway Calabasas California91302USA
| | - Karl Frank
- Campbell Hall School 4533 Laurel Canyon Boulevard Studio City California91607USA
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15
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Habitat loss and range shifts contribute to ecological generalization among reef fishes. Nat Ecol Evol 2021; 5:656-662. [PMID: 33686182 DOI: 10.1038/s41559-020-01342-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 10/05/2020] [Indexed: 01/31/2023]
Abstract
Human activities are altering the structure of ecological communities, often favouring generalists over specialists. For reef fishes, increasingly degraded habitats and climate-driven range shifts may independently augment generalization, particularly if fishes with least-specific habitat requirements are more likely to shift geographic ranges to track their thermal niche. Using a unique global dataset on temperate and tropical reef fishes and habitat composition, we calculated a species generalization index that empirically estimates the habitat niche breadth of each fish species. We then applied the species generalization index to evaluate potential impacts of habitat loss and range shifts across large scales, on coral and rocky reefs. Our analyses revealed consistent habitat-induced shifts in community structure that favoured generalist fishes following regional coral mortality events and between adjacent sea urchin barrens and kelp habitats. Analysis of the distribution of tropical fishes also identified the species generalization index as the most important trait in predicting their poleward range extent, more so than body or range size. Generalist tropical reef fishes penetrate further into subtropical and temperate zones than specialists. Dynamic responses of reef fishes to habitat degradation imply loss of specialists at local scales, while generalists will be broadly favoured under intensifying anthropogenic pressures. An increased focus on individual requirements of specialists could provide useful guidance for species threat assessments and conservation actions, while ecosystem and multi-species fisheries models should recognize increasing prevalence of generalists.
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16
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Molina-Hernández A, González-Barrios FJ, Perry CT, Álvarez-Filip L. Two decades of carbonate budget change on shifted coral reef assemblages: are these reefs being locked into low net budget states? Proc Biol Sci 2020; 287:20202305. [PMID: 33290684 DOI: 10.1098/rspb.2020.2305] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The ecology of coral reefs is rapidly shifting from historical baselines. One key-question is whether under these new, less favourable ecological conditions, coral reefs will be able to sustain key geo-ecological processes such as the capacity to accumulate carbonate structure. Here, we use data from 34 Caribbean reef sites to examine how the carbonate production, net erosion and net carbonate budgets, as well as the organisms underlying these processes, have changed over the past 15 years in the absence of further severe acute disturbances. We find that despite fundamental benthic ecological changes, these ecologically shifted coral assemblages have exhibited a modest but significant increase in their net carbonate budgets over the past 15 years. However, contrary to expectations this trend was driven by a decrease in erosion pressure, largely resulting from changes in the abundance and size-frequency distribution of parrotfishes, and not by an increase in rates of coral carbonate production. Although in the short term, the carbonate budgets seem to have benefitted marginally from reduced parrotfish erosion, the absence of these key substrate grazers, particularly of larger individuals, is unlikely to be conducive to reef recovery and will thus probably lock these reefs into low budget states.
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Affiliation(s)
- Ana Molina-Hernández
- Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Ciudad Universitaria 3000, C.P. 04510, Coyoacán, Ciudad de México, México.,Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
| | - F Javier González-Barrios
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
| | - Chris T Perry
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | - Lorenzo Álvarez-Filip
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
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17
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Size-specific recolonization success by coral-dwelling damselfishes moderates resilience to habitat loss. Sci Rep 2020; 10:17016. [PMID: 33046807 PMCID: PMC7550353 DOI: 10.1038/s41598-020-73979-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/05/2020] [Indexed: 11/08/2022] Open
Abstract
Increasing degradation of coral reef ecosystems and specifically, loss of corals is causing significant and widespread declines in the abundance of coral reef fishes, but the proximate cause(s) of these declines are largely unknown. Here, we examine specific responses to host coral mortality for three species of coral-dwelling damselfishes (Dascyllus aruanus, D. reticulatus, and Pomacentrus moluccensis), explicitly testing whether these fishes can successfully move and recolonize nearby coral hosts. Responses of fishes to localized coral loss was studied during population irruptions of coral feeding crown-of-thorns starfish, where starfish consumed 29 (34%) out of 85 coral colonies, of which 25 (86%) were occupied by coral-dwelling damselfishes. Damselfishes were not tagged or individually recognizable, but changes in the colonization of different coral hosts was assessed by carefully assessing the number and size of fishes on every available coral colony. Most damselfishes (> 90%) vacated dead coral hosts within 5 days, and either disappeared entirely (presumed dead) or relocated to nearby coral hosts. Displaced fishes only ever colonized corals already occupied by other coral-dwelling damselfishes (mostly conspecifics) and colonization success was strongly size-dependent. Despite movement of damselfishes to surviving corals, the local abundance of coral-dependent damselfishes declined in approximate accordance with the proportional loss of coral habitat. These results suggest that even if alternative coral hosts are locally abundant, there are significant biological constraints on movement of coral-dwelling damselfishes and recolonization of alternative coral habitats, such that localized persistence of habitat patches during moderate or patchy disturbances do not necessarily provide resilience against overall habitat loss.
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18
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Zimmerman JK, Willig MR, Hernández‐Delgado EA. Resistance, resilience, and vulnerability of social‐ecological systems to hurricanes in Puerto Rico. Ecosphere 2020. [DOI: 10.1002/ecs2.3159] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Jess K. Zimmerman
- Department of Environmental Sciences University of Puerto Rico San Juan Puerto Rico 00925 USA
| | - Michael R. Willig
- Institute of the Environment Center for Environmental Sciences & Engineering and Department of Ecology & Evolutionary Biology University of Connecticut Storrs Connecticut 06269 USA
| | - Edwin A. Hernández‐Delgado
- Department of Environmental Sciences University of Puerto Rico San Juan Puerto Rico 00925 USA
- Center for Applied Tropical Ecology and Conservation University of Puerto Rico San Juan Puerto Rico 00925 USA
- Sociedad Ambiente Marino San Juan Puerto Rico 00931 USA
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19
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Precht WF, Aronson RB, Gardner TA, Gill JA, Hawkins JP, Hernández-Delgado EA, Jaap WC, McClanahan TR, McField MD, Murdoch TJT, Nugues MM, Roberts CM, Schelten CK, Watkinson AR, Côté IM. The timing and causality of ecological shifts on Caribbean reefs. ADVANCES IN MARINE BIOLOGY 2020; 87:331-360. [PMID: 33293016 DOI: 10.1016/bs.amb.2020.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Caribbean reefs have experienced unprecedented changes in the past four decades. Of great concern is the perceived widespread shift from coral to macroalgal dominance and the question of whether it represents a new, stable equilibrium for coral-reef communities. The primary causes of the shift-grazing pressure (top-down), nutrient loading (bottom-up) or direct coral mortality (side-in)-still remain somewhat controversial in the coral-reef literature. We have attempted to tease out the relative importance of each of these causes. Four insights emerge from our analysis of an early regional dataset of information on the benthic composition of Caribbean reefs spanning the years 1977-2001. First, although three-quarters of reef sites have experienced coral declines concomitant with macroalgal increases, fewer than 10% of the more than 200 sites studied were dominated by macroalgae in 2001, by even the most conservative definition of dominance. Using relative dominance as the threshold, a total of 49 coral-to-macroalgae shifts were detected. This total represents ~35% of all sites that were dominated by coral at the start of their monitoring periods. Four shifts (8.2%) occurred because of coral loss with no change in macroalgal cover, 15 (30.6%) occurred because of macroalgal gain without coral loss, and 30 (61.2%) occurred owing to concomitant coral decline and macroalgal increase. Second, the timing of shifts at the regional scale is most consistent with the side-in model of reef degradation, which invokes coral mortality as a precursor to macroalgal takeover, because more shifts occurred after regional coral-mortality events than expected by chance. Third, instantaneous observations taken at the start and end of the time-series for individual sites showed these reefs existed along a continuum of coral and macroalgal cover. The continuous, broadly negative relationship between coral and macroalgal cover suggests that in some cases coral-to-macroalgae phase shifts may be reversed by removing sources of perturbation or restoring critical components such as the herbivorous sea urchin Diadema antillarum to the system. The five instances in which macroalgal dominance was reversed corroborate the conclusion that macroalgal dominance is not a stable, alternative community state as has been commonly assumed. Fourth, the fact that the loss in regional coral cover and concomitant changes to the benthic community are related to punctuated, discrete events with known causes (i.e. coral disease and bleaching), lends credence to the hypothesis that coral reefs of the Caribbean have been under assault from climate-change-related maladies since the 1970s.
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Affiliation(s)
- William F Precht
- Marine and Coastal Programs, Dial Cordy and Associates, Miami, FL, United States.
| | - Richard B Aronson
- Department of Ocean Engineering and Marine Sciences, Florida Institute of Technology, Melbourne, FL, United States
| | | | - Jennifer A Gill
- Centre for Ecology, Evolution and Conservation, School of Biological Sciences, University of East Anglia, Norwich, United Kingdom
| | - Julie P Hawkins
- Environment Department, University of York, York, United Kingdom
| | - Edwin A Hernández-Delgado
- Department of Environmental Sciences and Center for Applied Tropical Ecology and Conservation, Applied Marine Ecology Laboratory, University of Puerto Rico, San Juan, Puerto Rico
| | - Walter C Jaap
- Lithophyte Research LLC, Saint Petersburg, FL, United States
| | - Tim R McClanahan
- Wildlife Conservation Society, Marine Programs, Bronx, NY, United States
| | | | | | - Maggy M Nugues
- EPHE, Laboratoire d'Excellence "CORAIL", PSL Research University, UPVD, CNRS, USR, Perpignan, France
| | - Callum M Roberts
- Environment Department, University of York, York, United Kingdom
| | | | - Andrew R Watkinson
- Living with Environmental Change, School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
| | - Isabelle M Côté
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
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20
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Bradley P, Jessup B, Pittman SJ, Jeffrey CFG, Ault JS, Carrubba L, Lilyestrom C, Appeldoorn RS, Schärer MT, Walker BK, McField M, Santavy DL, Smith TB, García-Moliner G, Smith SG, Huertas E, Gerritsen J, Oliver LM, Horstmann C, Jackson SK. Development of a reef fish biological condition gradient model with quantitative decision rules for the protection and restoration of coral reef ecosystems. MARINE POLLUTION BULLETIN 2020; 159:111387. [PMID: 32827871 PMCID: PMC8717739 DOI: 10.1016/j.marpolbul.2020.111387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 06/11/2020] [Accepted: 06/16/2020] [Indexed: 05/09/2023]
Abstract
Coral reef ecosystems are declining due to multiple interacting stressors. A bioassessment framework focused on stressor-response associations was developed to help organize and communicate complex ecological information to support coral reef conservation. This study applied the Biological Condition Gradient (BCG), initially developed for freshwater ecosystems, to fish assemblages of U.S. Caribbean coral reef ecosystems. The reef fish BCG describes how biological conditions changed incrementally along a gradient of increasing anthropogenic stress. Coupled with physical and chemical water quality data, the BGC forms a scientifically defensible basis to prioritize, protect and restore water bodies containing coral reefs. Through an iterative process, scientists from across the U.S. Caribbean used fishery-independent survey data and expert knowledge to develop quantitative decision rules to describe six levels of coral reef ecosystem condition. The resultant reef fish BCG provides an effective tool for identifying healthy and degraded coral reef ecosystems and has potential for global application.
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Affiliation(s)
| | | | | | - Christopher F G Jeffrey
- CSS-Inc., Fairfax, VA, USA; Under Contract to NOAA, National Centers for Coastal Ocean Science, Marine Spatial Ecology Division, Biogeography Branch, Silver Spring, MD, USA
| | - Jerald S Ault
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, Miami, FL, USA
| | | | - Craig Lilyestrom
- Puerto Rico Department of Natural and Environmental Resources, San Juan, PR, USA
| | | | | | - Brian K Walker
- Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, Fort Lauderdale, FL, USA
| | | | - Deborah L Santavy
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA.
| | - Tyler B Smith
- University of the Virgin Islands, St. Thomas, VI, USA
| | | | - Steven G Smith
- University of Miami, Rosenstiel School of Marine and Atmospheric Science, Miami, FL, USA
| | - Evelyn Huertas
- U.S. Environmental Protection Agency, Region 2, Guaynabo, PR, USA
| | | | - Leah M Oliver
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA
| | - Christina Horstmann
- U.S. Environmental Protection Agency (US EPA), Office of Research and Development (ORD), Center for Environmental, Measurement and Modeling (CEMM), Gulf Ecosystem Measurement and Modeling Division (GEMMD), Gulf Breeze, FL, USA; Oak Ridge Institute for Science Education Fellow, US EPA, ORD, CEMM, GEMMD, Gulf Breeze, FL, USA
| | - Susan K Jackson
- U.S. Environmental Protection Agency, Office of Water, Washington, DC, USA
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21
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Lester SE, Rassweiler A, McCoy SJ, Dubel AK, Donovan MK, Miller MW, Miller SD, Ruttenberg BI, Samhouri JF, Hay ME. Caribbean reefs of the Anthropocene: Variance in ecosystem metrics indicates bright spots on coral depauperate reefs. GLOBAL CHANGE BIOLOGY 2020; 26:4785-4799. [PMID: 32691514 PMCID: PMC7497265 DOI: 10.1111/gcb.15253] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/09/2020] [Accepted: 06/12/2020] [Indexed: 05/18/2023]
Abstract
Dramatic coral loss has significantly altered many Caribbean reefs, with potentially important consequences for the ecological functions and ecosystem services provided by reef systems. Many studies examine coral loss and its causes-and often presume a universal decline of ecosystem services with coral loss-rather than evaluating the range of possible outcomes for a diversity of ecosystem functions and services at reefs varying in coral cover. We evaluate 10 key ecosystem metrics, relating to a variety of different reef ecosystem functions and services, on 328 Caribbean reefs varying in coral cover. We focus on the range and variability of these metrics rather than on mean responses. In contrast to a prevailing paradigm, we document high variability for a variety of metrics, and for many the range of outcomes is not related to coral cover. We find numerous "bright spots," where herbivorous fish biomass, density of large fishes, fishery value, and/or fish species richness are high, despite low coral cover. Although it remains critical to protect and restore corals, understanding variability in ecosystem metrics among low-coral reefs can facilitate the maintenance of reefs with sustained functions and services as we work to restore degraded systems. This framework can be applied to other ecosystems in the Anthropocene to better understand variance in ecosystem service outcomes and identify where and why bright spots exist.
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Affiliation(s)
- Sarah E. Lester
- Department of GeographyFlorida State UniversityTallahasseeFLUSA
| | - Andrew Rassweiler
- Department of Biological ScienceFlorida State UniversityTallahasseeFLUSA
| | - Sophie J. McCoy
- Department of Biological ScienceFlorida State UniversityTallahasseeFLUSA
| | - Alexandra K. Dubel
- Department of Biological ScienceFlorida State UniversityTallahasseeFLUSA
| | - Mary K. Donovan
- Hawai'i Institute of Marine BiologyUniversity of Hawai'i at MānoaKāne'oheHIUSA
- Marine Science InstituteUniversity of CaliforniaSanta BarbaraCAUSA
| | | | - Scott D. Miller
- Department of Biological ScienceFlorida State UniversityTallahasseeFLUSA
| | - Benjamin I. Ruttenberg
- Biological Sciences Department and Center for Coastal Marine SciencesCalifornia Polytechnic State UniversitySan Luis ObispoCAUSA
| | - Jameal F. Samhouri
- Conservation Biology DivisionNorthwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationSeattleWAUSA
| | - Mark E. Hay
- School of Biological SciencesGeorgia Institute of TechnologyAtlantaGAUSA
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22
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Contreras-Silva AI, Tilstra A, Migani V, Thiel A, Pérez-Cervantes E, Estrada-Saldívar N, Elias-Ilosvay X, Mott C, Alvarez-Filip L, Wild C. A meta-analysis to assess long-term spatiotemporal changes of benthic coral and macroalgae cover in the Mexican Caribbean. Sci Rep 2020; 10:8897. [PMID: 32483234 PMCID: PMC7264131 DOI: 10.1038/s41598-020-65801-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 05/06/2020] [Indexed: 11/09/2022] Open
Abstract
Coral reefs in the wider Caribbean declined in hard coral cover by ~80% since the 1970s, but spatiotemporal analyses for sub-regions are lacking. Here, we explored benthic change patterns in the Mexican Caribbean reefs through meta-analysis between 1978 and 2016 including 125 coral reef sites. Findings revealed that hard coral cover decreased from ~26% in the 1970s to 16% in 2016, whereas macroalgae cover increased to ~30% in 2016. Both groups showed high spatiotemporal variability. Hard coral cover declined in total by 12% from 1978 to 2004 but increased again by 5% between 2005 and 2016 indicating some coral recovery after the 2005 mass bleaching event and hurricane impacts. In 2016, more than 80% of studied reefs were dominated by macroalgae, while only 15% were dominated by hard corals. This stands in contrast to 1978 when all reef sites surveyed were dominated by hard corals. This study is among the first within the Caribbean region that reports local recovery in coral cover in the Caribbean, while other Caribbean reefs have failed to recover. Most Mexican Caribbean coral reefs are now no longer dominated by hard corals. In order to prevent further reef degradation, viable and reliable conservation alternatives are required.
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Affiliation(s)
- Ameris I Contreras-Silva
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße UFT, 28359, Bremen, Germany.
| | - Arjen Tilstra
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße UFT, 28359, Bremen, Germany
| | - Valentina Migani
- Population and Evolutionary Ecology Group, Institute of Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße 5, 28359, Bremen, Germany
| | - Andra Thiel
- Population and Evolutionary Ecology Group, Institute of Ecology, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße 5, 28359, Bremen, Germany
| | - Esmeralda Pérez-Cervantes
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico
| | - Nuria Estrada-Saldívar
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico
| | - Xochitl Elias-Ilosvay
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße UFT, 28359, Bremen, Germany
| | - Claudius Mott
- Remote Sensing Solutions GmbH, Dingolfinger Str. 9, 81673, München, Germany
| | - Lorenzo Alvarez-Filip
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, Mexico.
| | - Christian Wild
- Marine Ecology Department, Faculty of Biology and Chemistry, University of Bremen, Leobener Straße UFT, 28359, Bremen, Germany.
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23
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Lin CH, De Gracia B, Pierotti MER, Andrews AH, Griswold K, O’Dea A. Reconstructing reef fish communities using fish otoliths in coral reef sediments. PLoS One 2019; 14:e0218413. [PMID: 31199853 PMCID: PMC6568422 DOI: 10.1371/journal.pone.0218413] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 05/31/2019] [Indexed: 11/18/2022] Open
Abstract
Little is known about long-term changes in coral reef fish communities. Here we present a new technique that leverages fish otoliths in reef sediments to reconstruct coral reef fish communities. We found over 5,400 otoliths in 169 modern and mid-Holocene bulk samples from Caribbean Panama and Dominican Republic mid-Holocene and modern reefs, demonstrating otoliths are abundant in reef sediments. With a specially-built reference collection, we were able to assign over 4,400 otoliths to one of 56 taxa (35 families) though mostly at genus and family level. Many otoliths were from juvenile fishes for which identification is challenging. Richness (by rarefaction) of otolith assemblages was slightly higher in modern than mid-Holocene reefs, but further analyses are required to elucidate the underlying causes. We compared the living fish communities, sampled using icthyocide, with the sediment otolith assemblages on four reefs finding the otolith assemblages faithfully capture the general composition of the living fish communities. Radiocarbon dating performed directly on the otoliths suggests that relatively little mixing of sediment layers particularly on actively accreting branching coral reefs. All otolith assemblages were strongly dominated by small, fast-turnover fish taxa and juvenile individuals, and our exploration on taxonomy, functional ecology and taphonomy lead us to the conclusion that intense predation is likely the most important process for otolith accumulation in reef sediments. We conclude that otolith assemblages in modern and fossil reef sediments can provide a powerful tool to explore ecological changes in reef fish communities over time and space.
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Affiliation(s)
- Chien-Hsiang Lin
- Center for Ecology and Environment, Tunghai University, Taichung, Taiwan
- Department of Life Science, Tunghai University, Taichung, Taiwan
| | | | | | - Allen H. Andrews
- Department of Oceanography, University of Hawaii at Manoa, HI, United States of America
| | - Katie Griswold
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
| | - Aaron O’Dea
- Smithsonian Tropical Research Institute, Balboa, Republic of Panama
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24
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Vermeij MJA, Latijnhouwers KRW, Dilrosun F, Chamberland VF, Dubé CE, Van Buurt G, Debrot AO. Historical changes (1905-present) in catch size and composition reflect altering fisheries practices on a small Caribbean island. PLoS One 2019; 14:e0217589. [PMID: 31194756 PMCID: PMC6564285 DOI: 10.1371/journal.pone.0217589] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/14/2019] [Indexed: 11/18/2022] Open
Abstract
Effective assessments of the status of Caribbean fish communities require historical baselines to adequately understand how much fish communities have changed through time. To identify such changes and their causes, we compiled a historical overview using data collected at the beginning (1905–1908), middle (1958–1965) and end (1984–2016) of the 20th century, of the artisanal fishing practices and their effects on fish populations around Curaçao, a small island in the southern Caribbean. We documented historical trends in total catch, species composition, and catch sizes per fisher per month for different types of fisheries and related these to technological and environmental changes affecting the island’s fisheries and fish communities. We found that since 1905, fishers targeted species increasingly farther from shore after species occurring closer to shore had become rare. This resulted in surprisingly similar catches in terms of weight, but not composition. Large predatory reef fishes living close to shore (e.g., large Epinephelid species) had virtually disappeared from catches around the mid-20th century, questioning the use of data from this period as baseline data for modern day fish assessments. Secondly, we compared fish landings to in-situ counts from 1969 to estimate the relative contributions of habitat destruction and overfishing to the changes in fish abundance around Curaçao. The decline in coral dominated reef communities corresponded to a concurrent decrease in the abundance and diversity of smaller reef fish species not targeted by fishers, suggesting habitat loss, in addition to fishing, caused the observed declines in reef fish abundance around Curaçao.
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Affiliation(s)
- Mark J. A. Vermeij
- Carmabi Foundation, Willemstad, Curaçao
- Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands
- * E-mail:
| | - Kelly R. W. Latijnhouwers
- Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands
| | - Faisal Dilrosun
- Department of Agriculture and Fisheries, Ministry of Health, Environment and Nature, Willemstad, Curaçao
| | - Valérie F. Chamberland
- Carmabi Foundation, Willemstad, Curaçao
- Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands
| | - Caroline E. Dubé
- Carmabi Foundation, Willemstad, Curaçao
- Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Adolphe O. Debrot
- Carmabi Foundation, Willemstad, Curaçao
- Wageningen Marine Research, Den Helder, the Netherlands
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Rioja-Nieto R, Álvarez-Filip L. Coral reef systems of the Mexican Caribbean: Status, recent trends and conservation. MARINE POLLUTION BULLETIN 2019; 140:616-625. [PMID: 30005908 DOI: 10.1016/j.marpolbul.2018.07.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 06/27/2018] [Accepted: 07/02/2018] [Indexed: 06/08/2023]
Abstract
Over the last four decades the Mexican Caribbean has experienced intensive coastal development, and change on the reef system condition has already been observed. This paper describes the reef system characteristics, at local and seascape scales, and discusses the current status and trends, considering the main research efforts from academia and Non-Governmental Organizations. To date, the coral cover of most reefs in the region is between 15 and 20%, following a slight recovery on mean coral cover over the last decade. During this same period, fleshy macroalgae and herbivorous fish biomass appear to have increased. At seascape scales, an increase of macroalgae and the loss of seagrass habitat have been observed. Considering that anthropogenic and environmental disturbances will most likely increase, the establishment of newly protected areas in the Mexican Caribbean is appropriate, but sufficient accompanying funding is required.
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Affiliation(s)
- Rodolfo Rioja-Nieto
- Laboratorio de Análisis Espacial de Zonas Costeras, Unidad Multidisciplinaria de Docencia e Investigación-Sisal, Facultad de Ciencias, Universidad Nacional Autónoma de México, Carretera Sierra Papacal-Chuburná Puerto Km 5, Sierra Papacal, Yucatán 97302, México.
| | - Lorenzo Álvarez-Filip
- Biodiversity and Reef Conservation Laboratory, Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, México.
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Bruno JF, Côté IM, Toth LT. Climate Change, Coral Loss, and the Curious Case of the Parrotfish Paradigm: Why Don't Marine Protected Areas Improve Reef Resilience? ANNUAL REVIEW OF MARINE SCIENCE 2019; 11:307-334. [PMID: 30606097 DOI: 10.1146/annurev-marine-010318-095300] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Scientists have advocated for local interventions, such as creating marine protected areas and implementing fishery restrictions, as ways to mitigate local stressors to limit the effects of climate change on reef-building corals. However, in a literature review, we find little empirical support for the notion of managed resilience. We outline some reasons for why marine protected areas and the protection of herbivorous fish (especially parrotfish) have had little effect on coral resilience. One key explanation is that the impacts of local stressors (e.g., pollution and fishing) are often swamped by the much greater effect of ocean warming on corals. Another is the sheer complexity (including numerous context dependencies) of the five cascading links assumed by the managed-resilience hypothesis. If reefs cannot be saved by local actions alone, then it is time to face reef degradation head-on, by directly addressing anthropogenic climate change-the root cause of global coral decline.
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Affiliation(s)
- John F Bruno
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599-3280, USA;
| | - Isabelle M Côté
- Earth to Ocean Research Group, Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Lauren T Toth
- St. Petersburg Coastal and Marine Science Center, US Geological Survey, St. Petersburg, Florida 33701, USA
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Disturbance in Mesophotic Coral Ecosystems and Linkages to Conservation and Management. CORAL REEFS OF THE WORLD 2019. [DOI: 10.1007/978-3-319-92735-0_47] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Francis F, Filbee-Dexter K, Yan H, Côté I. Invertebrate herbivores: Overlooked allies in the recovery of degraded coral reefs? Glob Ecol Conserv 2019. [DOI: 10.1016/j.gecco.2019.e00593] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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29
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Seyedmousavi S, Bosco SDMG, de Hoog S, Ebel F, Elad D, Gomes RR, Jacobsen ID, Jensen HE, Martel A, Mignon B, Pasmans F, Piecková E, Rodrigues AM, Singh K, Vicente VA, Wibbelt G, Wiederhold NP, Guillot J. Fungal infections in animals: a patchwork of different situations. Med Mycol 2018. [PMID: 29538732 DOI: 10.1093/mmy/myx104] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The importance of fungal infections in both human and animals has increased over the last decades. This article represents an overview of the different categories of fungal infections that can be encountered in animals originating from environmental sources without transmission to humans. In addition, the endemic infections with indirect transmission from the environment, the zoophilic fungal pathogens with near-direct transmission, the zoonotic fungi that can be directly transmitted from animals to humans, mycotoxicoses and antifungal resistance in animals will also be discussed. Opportunistic mycoses are responsible for a wide range of diseases from localized infections to fatal disseminated diseases, such as aspergillosis, mucormycosis, candidiasis, cryptococcosis and infections caused by melanized fungi. The amphibian fungal disease chytridiomycosis and the Bat White-nose syndrome are due to obligatory fungal pathogens. Zoonotic agents are naturally transmitted from vertebrate animals to humans and vice versa. The list of zoonotic fungal agents is limited but some species, like Microsporum canis and Sporothrix brasiliensis from cats, have a strong public health impact. Mycotoxins are defined as the chemicals of fungal origin being toxic for warm-blooded vertebrates. Intoxications by aflatoxins and ochratoxins represent a threat for both human and animal health. Resistance to antifungals can occur in different animal species that receive these drugs, although the true epidemiology of resistance in animals is unknown, and options to treat infections caused by resistant infections are limited.
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Affiliation(s)
- Seyedmojtaba Seyedmousavi
- Molecular Microbiology Section, Laboratory of Clinical Microbiology and Immunology (LCMI), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Sandra de M G Bosco
- Department of Microbiology and Immunology, Institute of Biosciences-UNESP Univ Estadual Paulista Botucatu, São Paulo, Brazil
| | - Sybren de Hoog
- Westerdijk Fungal Biodiversity Institute, Utrecht, and Center of Expertise in Mycology of Radboudumc/CWZ, Nijmegen, The Netherlands
| | - Frank Ebel
- Institut für Infektionsmedizin und Zoonosen, Munich, Germany
| | - Daniel Elad
- Department of Clinical Bacteriology and Mycology, Kimron Veterinary Institute, Veterinary Services, Ministry of Agriculture, Beit Dagan, Israel
| | - Renata R Gomes
- Microbiology, Parasitology and Pathology Graduate Programme, Curitiba Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Hans Knöll Institute, Jena, Germany
| | | | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases. Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Bernard Mignon
- Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, FARAH (Fundamental and Applied Research for Animals & Health), University of Liège, Liège, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases. Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Elena Piecková
- Faculty of Medicine, Slovak Medical University, Faculty of Chemical and Food Technology, Slovak University of Technology, Bratislava, Slovakia
| | - Anderson Messias Rodrigues
- Department of Microbiology, Immunology and Parasitology, Federal University of São Paulo, São Paulo, Brazil
| | - Karuna Singh
- Department of Zoology, Mahila Mahavidyalaya, Banaras Hindu University, Varanasi, India
| | - Vania A Vicente
- Research Group Microbial Immunology, Hans Knöll Institute, Jena, Germany
| | - Gudrun Wibbelt
- Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Nathan P Wiederhold
- Fungus Testing Laboratory, Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Jacques Guillot
- Department of Parasitology, Mycology and Dermatology, EA Dynamyc UPEC, EnvA, Ecole nationale vétérinaire d'Alfort, Maisons-Alfort, France
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Abstract
AbstractCoastal ecosystems have been degraded by human activity over centuries, with loss of memory about past states resulting in shifted baselines. More recently conservation efforts have resulted in localized recoveries of species and ecosystems. Given the dynamism of ecosystem degradation and recovery, understanding how communities perceive long-term and recent changes is important for developing and implementing conservation measures. We interviewed stakeholders on three Caribbean islands and identified a shifted baseline with respect to the extent and degree of long-term declines in marine animal populations; stakeholders with more experience identified more species as depleted and key species as less abundant than those with less experience. Notably, the average respondent with < 15 years of experience listed no species as depleted despite clear evidence of declines. We also identified a phenomenon we call the policy placebo effect, in which interviewees perceived some animal populations as recently recovering following passage of new conservation legislation but in the absence of evidence for actual recovery. Although shifted baselines have a negative effect on conservation as they can lower recovery goals, the outcomes of a policy placebo effect are unclear. If the public prematurely perceives recovery, motivation for continued conservation could decline. Alternatively, perception of rapid success could lead communities to set more ambitious conservation goals.
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Invasive Lionfish (Pterois volitans/miles) feeding ecology in Biscayne National Park, Florida, USA. Biol Invasions 2018. [DOI: 10.1007/s10530-018-1705-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Variable density dependence and the restructuring of coral-reef fisheries across 25 years of exploitation. Sci Rep 2018; 8:5725. [PMID: 29636494 PMCID: PMC5893587 DOI: 10.1038/s41598-018-23971-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/15/2018] [Indexed: 12/14/2022] Open
Abstract
Variable density dependence within multispecies fisheries results in species restructuring as exploitation intensifies that is poorly understood. We examined unique species-based records across 25 years of exploitation to evaluate patterns, consequences, and predictions of species replacements within three coral-reef fisheries. Body-size was an expected determinant of species replacements, as larger fishes were consistently replaced by smaller, faster-growing counterparts. However, many species with similar sizes and growth rates responded differently. Naso unicornis, a primary component of coral-reef fisheries across the Pacific, was one of the most resilient species to exploitation despite having a similar maximum size and growth as many large parrotfishes that slowly disappeared from landings. Assessments conducted for all primary target species revealed clear distinctions in compensatory responses: 31% had diminishing size structures, 18% had diminishing proportional contribution, but only 5% showed both. Standard approaches to fisheries management assume constant rates of size-and-age restructuring and rely upon metrics such as fishing-versus-natural mortality. Instead, a deeper appreciation for varying recruitment rates may help to (re)define fisheries management units and reduce complexity in multispecies fisheries. We last consider our results alongside traditional knowledge and management in the Pacific that clearly appreciated species responses, but have been lost over the years.
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Seemann J, Yingst A, Stuart-Smith RD, Edgar GJ, Altieri AH. The importance of sponges and mangroves in supporting fish communities on degraded coral reefs in Caribbean Panama. PeerJ 2018; 6:e4455. [PMID: 29610704 PMCID: PMC5878927 DOI: 10.7717/peerj.4455] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 02/15/2018] [Indexed: 11/21/2022] Open
Abstract
Fish communities associated with coral reefs worldwide are threatened by habitat degradation and overexploitation. We assessed coral reefs, mangrove fringes, and seagrass meadows on the Caribbean coast of Panama to explore the influences of their proximity to one another, habitat cover, and environmental characteristics in sustaining biomass, species richness and trophic structure of fish communities in a degraded tropical ecosystem. We found 94% of all fish across all habitat types were of small body size (≤10 cm), with communities dominated by fishes that usually live in habitats of low complexity, such as Pomacentridae (damselfishes) and Gobiidae (gobies). Total fish biomass was very low, with the trend of small fishes from low trophic levels over-represented, and top predators under-represented, relative to coral reefs elsewhere in the Caribbean. For example, herbivorous fishes comprised 27% of total fish biomass in Panama relative to 10% in the wider Caribbean, and the small parrotfish Scarus iseri comprised 72% of the parrotfish biomass. We found evidence that non-coral biogenic habitats support reef-associated fish communities. In particular, the abundance of sponges on a given reef and proximity of mangroves were found to be important positive correlates of reef fish species richness, biomass, abundance and trophic structure. Our study indicates that a diverse fish community can persist on degraded coral reefs, and that the availability and arrangement within the seascape of other habitat-forming organisms, including sponges and mangroves, is critical to the maintenance of functional processes in such ecosystems.
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Affiliation(s)
- Janina Seemann
- MarineGEO, Smithsonian Tropical Research Institute, Panamá, Republic of Panama
| | - Alexandra Yingst
- MarineGEO, Smithsonian Tropical Research Institute, Panamá, Republic of Panama.,University of Pittsburgh, Pittsburgh, PA, United States of America
| | - Rick D Stuart-Smith
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Graham J Edgar
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia
| | - Andrew H Altieri
- MarineGEO, Smithsonian Tropical Research Institute, Panamá, Republic of Panama.,Department of Environmental Engineering Sciences, Engineering School of Sustainable Infrastructure and Environment, University of Florida, United States of America
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Ruttenberg B, Caselle JE, Estep AJ, Johnson AE, Marhaver KL, Richter LJ, Sandin SA, Vermeij MJA, Smith JE, Grenda D, Cannon A. Ecological assessment of the marine ecosystems of Barbuda, West Indies: Using rapid scientific assessment to inform ocean zoning and fisheries management. PLoS One 2018; 13:e0189355. [PMID: 29309413 PMCID: PMC5757985 DOI: 10.1371/journal.pone.0189355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 11/27/2017] [Indexed: 12/18/2022] Open
Abstract
To inform a community-based ocean zoning initiative, we conducted an intensive ecological assessment of the marine ecosystems of Barbuda, West Indies. We conducted 116 fish and 108 benthic surveys around the island, and measured the abundance and size structure of lobsters and conch at 52 and 35 sites, respectively. We found that both coral cover and fish biomass were similar to or lower than levels observed across the greater Caribbean; live coral cover and abundance of fishery target species, such as large snappers and groupers, was generally low. However, Barbuda lacks many of the high-relief forereef areas where similar work has been conducted in other Caribbean locations. The distribution of lobsters was patchy, making it difficult to quantify density at the island scale. However, the maximum size of lobsters was generally larger than in other locations in the Caribbean and similar to the maximum size reported 40 years ago. While the lobster population has clearly been heavily exploited, our data suggest that it is not as overexploited as in much of the rest of the Caribbean. Surveys of Barbuda’s Codrington Lagoon revealed many juvenile lobsters, but none of legal size (95 mm carapace length), suggesting that the lagoon functions primarily as nursery habitat. Conch abundance and size on Barbuda were similar to that of other Caribbean islands. Our data suggest that many of the regional threats observed on other Caribbean islands are present on Barbuda, but some resources—particularly lobster and conch—may be less overexploited than on other Caribbean islands. Local management has the potential to provide sustainability for at least some of the island’s marine resources. We show that a rapid, thorough ecological assessment can reveal clear conservation opportunities and facilitate rapid conservation action by providing the foundation for a community-driven policymaking process at the island scale.
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Affiliation(s)
- Benjamin Ruttenberg
- Department of Biological Sciences, California Polytechnic State University, San Luis Obispo, CA, United States of America
- * E-mail:
| | - Jennifer E. Caselle
- Marine Science Institute, University of California Santa Barbara, Santa Barbara, CA, United States of America
| | | | | | | | - Lee J. Richter
- South Florida Caribbean Network, National Park Service, St. John, USVI
| | - Stuart A. Sandin
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States of America
| | - Mark J. A. Vermeij
- South Florida Caribbean Network, National Park Service, St. John, USVI
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Jennifer E. Smith
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States of America
| | - David Grenda
- Independent Researcher, Lakeland, FL, United States of America
| | - Abigail Cannon
- Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States of America
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Suchley A, Alvarez-Filip L. Herbivory facilitates growth of a key reef-building Caribbean coral. Ecol Evol 2017; 7:11246-11256. [PMID: 29299297 PMCID: PMC5743540 DOI: 10.1002/ece3.3620] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/11/2017] [Accepted: 10/08/2017] [Indexed: 01/13/2023] Open
Abstract
The decline of reef-building corals in conjunction with shifts to short-lived opportunistic species has prompted concerns that Caribbean reef framework-building capacity has substantially diminished. Restoring herbivore populations may be a potential driver of coral recovery; however, the impact of herbivores on coral calcification has been little studied. We performed an exclusion experiment to evaluate the impact of herbivory on Orbicella faveolata coral growth over 14 months. The experiment consisted of three treatments: full exclusion cages; half cage procedural controls; and uncaged control plates, each with small O. faveolata colonies. We found that herbivorous fish exclusion had a substantial impact on both macroalgal cover and coral growth. Fleshy macroalgae reached 50% cover within some exclusion cages, but were almost absent from uncaged control plates. Critically, O. faveolata calcification rates were suppressed by almost half within exclusion cages, with monthly coral growth negatively related to overgrowth by fleshy macroalgae. These findings highlight the importance of herbivorous fishes for coral growth and the detrimental impact of macroalgal proliferation in the Caribbean. Policy makers and local managers should consider measures to protect herbivorous fishes and reduce macroalgal proliferation to enable coral communities to continue to grow and function.
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Affiliation(s)
- Adam Suchley
- Posgrado en Ciencias del Mar y Limnología Universidad Nacional Autónoma de México Mexico City Mexico
| | - Lorenzo Alvarez-Filip
- Biodiversity and Reef Conservation Laboratory Unidad Académica de Sistemas Arrecifales Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de México Puerto Morelos Mexico
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Silveira CB, Cavalcanti GS, Walter JM, Silva-Lima AW, Dinsdale EA, Bourne DG, Thompson CC, Thompson FL. Microbial processes driving coral reef organic carbon flow. FEMS Microbiol Rev 2017; 41:575-595. [PMID: 28486655 DOI: 10.1093/femsre/fux018] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 04/10/2017] [Indexed: 01/13/2023] Open
Abstract
Coral reefs are one of the most productive ecosystems on the planet, with primary production rates compared to that of rain forests. Benthic organisms release 10-50% of their gross organic production as mucus that stimulates heterotrophic microbial metabolism in the water column. As a result, coral reef microbes grow up to 50 times faster than open ocean communities. Anthropogenic disturbances cause once coral-dominated reefs to become dominated by fleshy organisms, with several outcomes for trophic relationships. Here we review microbial processes implicated in organic carbon flux in coral reefs displaying species phase shifts. The first section presents microbial players and interactions within the coral holobiont that contribute to reef carbon flow. In the second section, we identify four ecosystem-level microbial features that directly respond to benthic species phase shifts: community composition, biomass, metabolism and viral predation. The third section discusses the significance of microbial consumption of benthic organic matter to reef trophic relationships. In the fourth section, we propose that the 'microbial phase shifts' discussed here are conducive to lower resilience, facilitating the transition to new degradation states in coral reefs.
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Affiliation(s)
- Cynthia B Silveira
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil.,Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - Giselle S Cavalcanti
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil.,Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - Juline M Walter
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Arthur W Silva-Lima
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Elizabeth A Dinsdale
- Biology Department, San Diego State University, 5500 Campanille Dr, San Diego, CA 92182, USA
| | - David G Bourne
- College of Science and Engineering, James Cook University and Australian Institute of Marine Science, Townsville, Queensland 4810, Australia
| | - Cristiane C Thompson
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
| | - Fabiano L Thompson
- Institute of Biology and COPPE/SAGE, Federal University of Rio de Janeiro. Av. Carlos Chagas Filho, 373, Cidade Universitária, RJ 21941-599, Brazil
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Kadison E, Brandt M, Nemeth R, Martens J, Blondeau J, Smith T. Abundance of commercially important reef fish indicates different levels of over-exploitation across shelves of the U.S. Virgin Islands. PLoS One 2017; 12:e0180063. [PMID: 28704387 PMCID: PMC5509108 DOI: 10.1371/journal.pone.0180063] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 06/08/2017] [Indexed: 11/18/2022] Open
Abstract
The United States Virgin Islands are comprised of two separate insular platforms separated by the deep water Anegada Passage. Although managed by the same regulations, as one fishery, several physical and spatial differences exist between the two northern shelf islands, St. Thomas and St. John, and isolated St. Croix. Based on two long-term fisheries independent datasets, collected by the U.S. Virgin Islands Territorial Coral Reef Monitoring Program and the National Oceanographic and Atmospheric Administration Center for Coastal Monitoring and Assessment, there were significant differences between the northern USVI and St. Croix in both the occurrence and size of several species of large and commercially important reef fishes. These fishes are primarily apex piscivores and generally the first species over-exploited in small-scale fisheries. The disparities between the fish communities on the two island shelves cannot be explained solely by differences in habitat (coral cover, rugosity) or fisheries management, such as relative amount of marine protected area in local waters. They are instead probably caused by a combination of several other interrelated factors including water depth, fishing methodology, fishable area, and the presence or absence of viable fish spawning areas. This study considers those aspects, and illustrates the need for management of island artisanal fisheries that is tailored to the physical and spatial constraints imposed by insular platforms.
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Affiliation(s)
- Elizabeth Kadison
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, USVI, United States of America
- * E-mail:
| | - Marilyn Brandt
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, USVI, United States of America
| | - Richard Nemeth
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, USVI, United States of America
| | - Justin Martens
- U.S. Fish and Wildlife Service, Alpine, AZ, United States of America
| | - Jeremiah Blondeau
- NOAA Southwest Fisheries Science Center, 75 Virginia Beach Dr., Miami, FL, United States of America
| | - Tyler Smith
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, USVI, United States of America
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Crane NL, Nelson P, Abelson A, Precoda K, Rulmal J, Bernardi G, Paddack M. Atoll-scale patterns in coral reef community structure: Human signatures on Ulithi Atoll, Micronesia. PLoS One 2017; 12:e0177083. [PMID: 28489903 PMCID: PMC5425048 DOI: 10.1371/journal.pone.0177083] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 04/21/2017] [Indexed: 11/18/2022] Open
Abstract
The dynamic relationship between reefs and the people who utilize them at a subsistence level is poorly understood. This paper characterizes atoll-scale patterns in shallow coral reef habitat and fish community structure, and correlates these with environmental characteristics and anthropogenic factors, critical to conservation efforts for the reefs and the people who depend on them. Hierarchical clustering analyses by site for benthic composition and fish community resulted in the same 3 major clusters: cluster 1-oceanic (close proximity to deep water) and uninhabited (low human impact); cluster 2-oceanic and inhabited (high human impact); and cluster 3-lagoonal (facing the inside of the lagoon) and inhabited (highest human impact). Distance from village, reef exposure to deep water and human population size had the greatest effect in predicting the fish and benthic community structure. Our study demonstrates a strong association between benthic and fish community structure and human use across the Ulithi Atoll (Yap State, Federated States of Micronesia) and confirms a pattern observed by local people that an 'opportunistic' scleractinian coral (Montipora sp.) is associated with more highly impacted reefs. Our findings suggest that small human populations (subsistence fishing) can nevertheless have considerable ecological impacts on reefs due, in part, to changes in fishing practices rather than overfishing per se, as well as larger global trends. Findings from this work can assist in building local capacity to manage reef resources across an atoll-wide scale, and illustrates the importance of anthropogenic impact even in small communities.
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Affiliation(s)
- Nicole L. Crane
- Department of Biology, Cabrillo College, Aptos, California, United States of America
- Oceanic Society, Ross, California, United States of America
- One People One Reef, Santa Cruz, California, United States of America
| | - Peter Nelson
- One People One Reef, Santa Cruz, California, United States of America
- H. T. Harvey & Associates, Bldg D, Los Gatos, California, United States of America
| | - Avigdor Abelson
- One People One Reef, Santa Cruz, California, United States of America
- Department of Zoology, Tel Aviv University, Ramat Aviv, Israel
| | - Kristin Precoda
- One People One Reef, Santa Cruz, California, United States of America
- Marine Studies Institute, University of Sydney, Sydney, New South Wales, Australia
| | - John Rulmal
- One People One Reef, Santa Cruz, California, United States of America
- Ulithi Falalop Community Action Program, Yap, Federated States of Micronesia
| | - Giacomo Bernardi
- One People One Reef, Santa Cruz, California, United States of America
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California, United States of America
| | - Michelle Paddack
- One People One Reef, Santa Cruz, California, United States of America
- Santa Barbara City College, Santa Barbara, California, United States of America
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Social interactions among grazing reef fish drive material flux in a coral reef ecosystem. Proc Natl Acad Sci U S A 2017; 114:4703-4708. [PMID: 28396400 DOI: 10.1073/pnas.1615652114] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In human financial and social systems, exchanges of information among individuals cause speculative bubbles, behavioral cascades, and other correlated actions that profoundly influence system-level function. Exchanges of information are also widespread in ecological systems, but their effects on ecosystem-level processes are largely unknown. Herbivory is a critical ecological process in coral reefs, where diverse assemblages of fish maintain reef health by controlling the abundance of algae. Here, we show that social interactions have a major effect on fish grazing rates in a reef ecosystem. We combined a system for observing and manipulating large foraging areas in a coral reef with a class of dynamical decision-making models to reveal that reef fish use information about the density and actions of nearby fish to decide when to feed on algae and when to flee foraging areas. This "behavioral coupling" causes bursts of feeding activity that account for up to 68% of the fish community's consumption of algae. Moreover, correlations in fish behavior induce a feedback, whereby each fish spends less time feeding when fewer fish are present, suggesting that reducing fish stocks may not only reduce total algal consumption but could decrease the amount of algae each remaining fish consumes. Our results demonstrate that social interactions among consumers can have a dominant effect on the flux of energy and materials through ecosystems, and our methodology paves the way for rigorous in situ measurements of the behavioral rules that underlie ecological rates in other natural systems.
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Okazaki RR, Towle EK, van Hooidonk R, Mor C, Winter RN, Piggot AM, Cunning R, Baker AC, Klaus JS, Swart PK, Langdon C. Species-specific responses to climate change and community composition determine future calcification rates of Florida Keys reefs. GLOBAL CHANGE BIOLOGY 2017; 23:1023-1035. [PMID: 27561209 DOI: 10.1111/gcb.13481] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Revised: 08/15/2016] [Accepted: 08/16/2016] [Indexed: 06/06/2023]
Abstract
Anthropogenic climate change compromises reef growth as a result of increasing temperatures and ocean acidification. Scleractinian corals vary in their sensitivity to these variables, suggesting species composition will influence how reef communities respond to future climate change. Because data are lacking for many species, most studies that model future reef growth rely on uniform scleractinian calcification sensitivities to temperature and ocean acidification. To address this knowledge gap, calcification of twelve common and understudied Caribbean coral species was measured for two months under crossed temperatures (27, 30.3 °C) and CO2 partial pressures (pCO2 ) (400, 900, 1300 μatm). Mixed-effects models of calcification for each species were then used to project community-level scleractinian calcification using Florida Keys reef composition data and IPCC AR5 ensemble climate model data. Three of the four most abundant species, Orbicella faveolata, Montastraea cavernosa, and Porites astreoides, had negative calcification responses to both elevated temperature and pCO2 . In the business-as-usual CO2 emissions scenario, reefs with high abundances of these species had projected end-of-century declines in scleractinian calcification of >50% relative to present-day rates. Siderastrea siderea, the other most common species, was insensitive to both temperature and pCO2 within the levels tested here. Reefs dominated by this species had the most stable end-of-century growth. Under more optimistic scenarios of reduced CO2 emissions, calcification rates throughout the Florida Keys declined <20% by 2100. Under the most extreme emissions scenario, projected declines were highly variable among reefs, ranging 10-100%. Without considering bleaching, reef growth will likely decline on most reefs, especially where resistant species like S. siderea are not already dominant. This study demonstrates how species composition influences reef community responses to climate change and how reduced CO2 emissions can limit future declines in reef calcification.
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Affiliation(s)
- Remy R Okazaki
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
- Joint Institute for the Study of the Atmosphere and Ocean, University of Washington, 3737 Brooklyn Ave NE, Seattle, WA, 98195, USA
- NOAA Pacific Marine Environmental Laboratory, 7600 Sandpoint Way NE, Seattle, WA, 98115, USA
| | - Erica K Towle
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Ruben van Hooidonk
- Ocean Chemistry and Ecosystems Division, NOAA Atlantic Oceanographic and Meteorological Laboratory, 4301 Rickenbacker Cswy, Miami, FL, 33149, USA
- Cooperative Institute for Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Carolina Mor
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Rivah N Winter
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Alan M Piggot
- Department of Marine Geosciences, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Ross Cunning
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Andrew C Baker
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - James S Klaus
- Department of Geological Sciences, University of Miami, 1320 S. Dixie Hwy, Coral Gables, FL, 33124, USA
| | - Peter K Swart
- Department of Marine Geosciences, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
| | - Chris Langdon
- Department of Marine Biology and Ecology, University of Miami Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Cswy, Miami, FL, 33149, USA
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Valdivia A, Cox CE, Bruno JF. Predatory fish depletion and recovery potential on Caribbean reefs. SCIENCE ADVANCES 2017; 3:e1601303. [PMID: 28275730 PMCID: PMC5332153 DOI: 10.1126/sciadv.1601303] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 01/16/2017] [Indexed: 05/11/2023]
Abstract
The natural, prehuman abundance of most large predators is unknown because of the lack of historical data and a limited understanding of the natural factors that control their populations. Determining the supportable predator biomass at a given location (that is, the predator carrying capacity) would help managers to optimize protection and would provide site-specific recovery goals. We assess the relationship between predatory reef fish biomass and several anthropogenic and environmental variables at 39 reefs across the Caribbean to (i) estimate their roles determining local predator biomass and (ii) determine site-specific recovery potential if fishing was eliminated. We show that predatory reef fish biomass tends to be higher in marine reserves but is strongly negatively related to human activities, especially coastal development. However, human activities and natural factors, including reef complexity and prey abundance, explain more than 50% of the spatial variation in predator biomass. Comparing site-specific predator carrying capacities to field observations, we infer that current predatory reef fish biomass is 60 to 90% lower than the potential supportable biomass in most sites, even within most marine reserves. We also found that the scope for recovery varies among reefs by at least an order of magnitude. This suggests that we could underestimate unfished biomass at sites that provide ideal conditions for predators or greatly overestimate that of seemingly predator-depleted sites that may have never supported large predator populations because of suboptimal environmental conditions.
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Affiliation(s)
- Abel Valdivia
- Center for Biological Diversity, 1212 Broadway Suite 800, Oakland, CA 94612, USA
- Corresponding author.
| | - Courtney Ellen Cox
- National Museum of Natural History, 1000 Constitution Avenue Northwest, Washington, DC 20560, USA
| | - John Francis Bruno
- Department of Biology, University of North Carolina at Chapel Hill, Wilson Hall, 120 South Road, Chapel Hill, NC 27599, USA
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Januchowski-Hartley FA, Graham NAJ, Wilson SK, Jennings S, Perry CT. Drivers and predictions of coral reef carbonate budget trajectories. Proc Biol Sci 2017; 284:20162533. [PMID: 28123092 PMCID: PMC5310043 DOI: 10.1098/rspb.2016.2533] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/03/2017] [Indexed: 11/12/2022] Open
Abstract
Climate change is one of the greatest threats to the long-term maintenance of coral-dominated tropical ecosystems, and has received considerable attention over the past two decades. Coral bleaching and associated mortality events, which are predicted to become more frequent and intense, can alter the balance of different elements that are responsible for coral reef growth and maintenance. The geomorphic impacts of coral mass mortality have received relatively little attention, particularly questions concerning temporal recovery of reef carbonate production and the factors that promote resilience of reef growth potential. Here, we track the biological carbonate budgets of inner Seychelles reefs from 1994 to 2014, spanning the 1998 global bleaching event when these reefs lost more than 90% of coral cover. All 21 reefs had positive budgets in 1994, but in 2005 budgets were predominantly negative. By 2014, carbonate budgets on seven reefs were comparable with 1994, but on all reefs where an ecological regime shift to macroalgal dominance occurred, budgets remained negative through 2014. Reefs with higher massive coral cover, lower macroalgae cover and lower excavating parrotfish biomass in 1994 were more likely to have positive budgets post-bleaching. If mortality of corals from the 2016 bleaching event is as severe as that of 1998, our predictions based on past trends would suggest that six of eight reefs with positive budgets in 2014 would still have positive budgets by 2030. Our results highlight that reef accretion and framework maintenance cannot be assumed from the ecological state alone, and that managers should focus on conserving aspects of coral reefs that support resilient carbonate budgets.
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Affiliation(s)
- Fraser A Januchowski-Hartley
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
- UMR 248 MARBEC/UMR250 ENTROPIE, UM2-CNRS-IRD-IFREMER-UM1, Université Montpellier 2, Montpellier, France
| | - Nicholas A J Graham
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Queensland 4811, Australia
| | - Shaun K Wilson
- Department of Parks and Wildlife, Kensington, Perth, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Simon Jennings
- Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft NR33 0HT, UK
- School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK
| | - Chris T Perry
- Geography, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
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Harborne AR, Rogers A, Bozec YM, Mumby PJ. Multiple Stressors and the Functioning of Coral Reefs. ANNUAL REVIEW OF MARINE SCIENCE 2017; 9:445-468. [PMID: 27575738 DOI: 10.1146/annurev-marine-010816-060551] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Coral reefs provide critical services to coastal communities, and these services rely on ecosystem functions threatened by stressors. By summarizing the threats to the functioning of reefs from fishing, climate change, and decreasing water quality, we highlight that these stressors have multiple, conflicting effects on functionally similar groups of species and their interactions, and that the overall effects are often uncertain because of a lack of data or variability among taxa. The direct effects of stressors on links among functional groups, such as predator-prey interactions, are particularly uncertain. Using qualitative modeling, we demonstrate that this uncertainty of stressor impacts on functional groups (whether they are positive, negative, or neutral) can have significant effects on models of ecosystem stability, and reducing uncertainty is vital for understanding changes to reef functioning. This review also provides guidance for future models of reef functioning, which should include interactions among functional groups and the cumulative effect of stressors.
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Affiliation(s)
- Alastair R Harborne
- Department of Biological Sciences, Florida International University, North Miami, Florida 33181;
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Alice Rogers
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Yves-Marie Bozec
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
| | - Peter J Mumby
- Marine Spatial Ecology Lab and Australian Research Council Centre of Excellence for Coral Reef Studies, School of Biological Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia; , ,
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44
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Sangil C, Guzman HM. Assessing the herbivore role of the sea-urchin Echinometra viridis: Keys to determine the structure of communities in disturbed coral reefs. MARINE ENVIRONMENTAL RESEARCH 2016; 120:202-213. [PMID: 27591516 DOI: 10.1016/j.marenvres.2016.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/11/2016] [Accepted: 08/23/2016] [Indexed: 06/06/2023]
Abstract
Echinometra viridis previously was considered a cryptic species unable to control the development and growth of macroalgae on coral reefs. Its role as a herbivore was seen as minor compared to other grazers present on the reef. However, the present disturbed state of some reefs has highlighted the role played by this sea-urchin. Combining field data with experiments on the Caribbean coast of Panama, we demonstrate that the current community organization on disturbed coral reefs in the Mesoamerican Caribbean is largely due to the action of E. viridis. It is the most abundant sea-urchin species, together with two others (Diadema antillarum and Echinometra lucunter). Field data also indicate that the relationship between its density and the abundance of macroalgae is stronger and it is more negative in impact than those of the other two. However, the niche this urchin exploits most efficiently is confined to leeward reefs with low levels of sedimentation. Outside these habitats, their populations are not decisive in controlling macroalgal growth. Grazing experiments showed that E. viridis consumes more fresh macroalgae per day and per weight of sea-urchin, and is a more effective grazer than D. antillarum or E. lucunter. E. viridis showed food preferences for early-successional turf macroalgae (Acanthophora spicifera), avoiding the less palatable late-successional and fleshy macroalgae (Lobophora variegata, Halimeda opuntia). However, it becomes a generalist herbivore feeding on all varieties of macroalgae when resources are scarce. H. opuntia is the macroalga that most resists E. viridis activity, which may explain its wide distribution.
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Affiliation(s)
- Carlos Sangil
- Department of Botany, Ecology and Plant Physiology, University of La Laguna, Canary Islands, Spain; Departament of Animal Biology, Soil Science and Geology, University of La Laguna, Canary Islands, Spain.
| | - Hector M Guzman
- Smithsonian Tropical Research Institute, Smithsonian Institution, Panama City, Panama
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45
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Alemu I JB. The status and management of the lionfish, Pterois sp. in Trinidad and Tobago. MARINE POLLUTION BULLETIN 2016; 109:402-408. [PMID: 27236231 DOI: 10.1016/j.marpolbul.2016.05.042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/13/2016] [Accepted: 05/18/2016] [Indexed: 06/05/2023]
Abstract
Trinidad and Tobago was the last Caribbean island to be invaded by the lionfish and since its invasion in 2012 they have spread to most coral reef and hard bottom environments. Standard reef fish surveys were used to assess lionfish population densities and size distributions from 2013-2015. Total lengths ranged between 6.2-40.4cm and 2.2-950g in weight. The length-weight relationship was described by W=0.0002L(2.5654). Fish densities were highest in the northeast Tobago at 326lionfish/ha and the lowest in the southwest Tobago at 10.5lionfish/ha. In order to curtail the spread of this invasive species, a culling programme was initiated at selected reefs to regularly remove lionfish at monthly intervals. On the selected reefs 26-30% reduction in mean lionfish biomass and 25-27% reduction in abundance was noted compared to control sites (p<0.05).
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Affiliation(s)
- Jahson B Alemu I
- Biodiversity and Ecology Research Programme, Institute of Marine Affairs, Hilltop Lane, Chaguaramas, W.I., Trinidad and Tobago.
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46
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Suchley A, McField MD, Alvarez-Filip L. Rapidly increasing macroalgal cover not related to herbivorous fishes on Mesoamerican reefs. PeerJ 2016; 4:e2084. [PMID: 27280075 PMCID: PMC4893329 DOI: 10.7717/peerj.2084] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 05/05/2016] [Indexed: 12/28/2022] Open
Abstract
Long-term phase shifts from coral to macroalgal dominated reef systems are well documented in the Caribbean. Although the impact of coral diseases, climate change and other factors is acknowledged, major herbivore loss through disease and overfishing is often assigned a primary role. However, direct evidence for the link between herbivore abundance, macroalgal and coral cover is sparse, particularly over broad spatial scales. In this study we use a database of coral reef surveys performed at 85 sites along the Mesoamerican Reef of Mexico, Belize, Guatemala and Honduras, to examine potential ecological links by tracking site trajectories over the period 2005–2014. Despite the long-term reduction of herbivory capacity reported across the Caribbean, the Mesoamerican Reef region displayed relatively low macroalgal cover at the onset of the study. Subsequently, increasing fleshy macroalgal cover was pervasive. Herbivorous fish populations were not responsible for this trend as fleshy macroalgal cover change was not correlated with initial herbivorous fish biomass or change, and the majority of sites experienced increases in macroalgae browser biomass. This contrasts the coral reef top-down herbivore control paradigm and suggests the role of external factors in making environmental conditions more favourable for algae. Increasing macroalgal cover typically suppresses ecosystem services and leads to degraded reef systems. Consequently, policy makers and local coral reef managers should reassess the focus on herbivorous fish protection and consider complementary measures such as watershed management in order to arrest this trend.
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Affiliation(s)
- Adam Suchley
- Posgrado en Ciencias del Mar y Limnología, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad de México, México; Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Puerto Morelos, Quintana Roo, México
| | - Melanie D McField
- Healthy Reefs for Healthy People Initiative, Smithsonian Institution , Ft Lauderdale, Florida , USA
| | - Lorenzo Alvarez-Filip
- Unidad Académica de Sistemas Arrecifales, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México , Puerto Morelos, Quintana Roo , México
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Reef Fish Survey Techniques: Assessing the Potential for Standardizing Methodologies. PLoS One 2016; 11:e0153066. [PMID: 27111085 PMCID: PMC4844186 DOI: 10.1371/journal.pone.0153066] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 03/23/2016] [Indexed: 11/19/2022] Open
Abstract
Dramatic changes in populations of fishes living on coral reefs have been documented globally and, in response, the research community has initiated efforts to assess and monitor reef fish assemblages. A variety of visual census techniques are employed, however results are often incomparable due to differential methodological performance. Although comparability of data may promote improved assessment of fish populations, and thus management of often critically important nearshore fisheries, to date no standardized and agreed-upon survey method has emerged. This study describes the use of methods across the research community and identifies potential drivers of method selection. An online survey was distributed to researchers from academic, governmental, and non-governmental organizations internationally. Although many methods were identified, 89% of survey-based projects employed one of three methods–belt transect, stationary point count, and some variation of the timed swim method. The selection of survey method was independent of the research design (i.e., assessment goal) and region of study, but was related to the researcher’s home institution. While some researchers expressed willingness to modify their current survey protocols to more standardized protocols (76%), their willingness decreased when methodologies were tied to long-term datasets spanning five or more years. Willingness to modify current methodologies was also less common among academic researchers than resource managers. By understanding both the current application of methods and the reported motivations for method selection, we hope to focus discussions towards increasing the comparability of quantitative reef fish survey data.
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48
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Management Strategy Evaluation Applied to Coral Reef Ecosystems in Support of Ecosystem-Based Management. PLoS One 2016; 11:e0152577. [PMID: 27023183 PMCID: PMC4811577 DOI: 10.1371/journal.pone.0152577] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 03/16/2016] [Indexed: 12/02/2022] Open
Abstract
Ecosystem modelling is increasingly used to explore ecosystem-level effects of changing environmental conditions and management actions. For coral reefs there has been increasing interest in recent decades in the use of ecosystem models for evaluating the effects of fishing and the efficacy of marine protected areas. However, ecosystem models that integrate physical forcings, biogeochemical and ecological dynamics, and human induced perturbations are still underdeveloped. We applied an ecosystem model (Atlantis) to the coral reef ecosystem of Guam using a suite of management scenarios prioritized in consultation with local resource managers to review the effects of each scenario on performance measures related to the ecosystem, the reef-fish fishery (e.g., fish landings) and coral habitat. Comparing tradeoffs across the selected scenarios showed that each scenario performed best for at least one of the selected performance indicators. The integrated ‘full regulation’ scenario outperformed other scenarios with four out of the six performance metrics at the cost of reef-fish landings. This model application quantifies the socio-ecological costs and benefits of alternative management scenarios. When the effects of climate change were taken into account, several scenarios performed equally well, but none prevented a collapse in coral biomass over the next few decades assuming a business-as-usual greenhouse gas emissions scenario.
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Bégin C, Schelten CK, Nugues MM, Hawkins J, Roberts C, Côté IM. Effects of Protection and Sediment Stress on Coral Reefs in Saint Lucia. PLoS One 2016; 11:e0146855. [PMID: 26845451 PMCID: PMC4742058 DOI: 10.1371/journal.pone.0146855] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 12/21/2015] [Indexed: 11/18/2022] Open
Abstract
The extent to which Marine Protected Areas (MPAs) benefit corals is contentious. On one hand, MPAs could enhance coral growth and survival through increases in herbivory within their borders; on the other, they are unlikely to prevent disturbances, such as terrestrial runoff, that originate outside their boundaries. We examined the effect of spatial protection and terrestrial sediment on the benthic composition of coral reefs in Saint Lucia. In 2011 (10 to 16 years after MPAs were created), we resurveyed 21 reefs that had been surveyed in 2001 and analyzed current benthic assemblages as well as changes in benthic cover over that decade in relation to protection status, terrestrial sediment influence (measured as the proportion of terrigenous material in reef-associated sediment) and depth. The cover of all benthic biotic components has changed significantly over the decade, including a decline in coral and increase in macroalgae. Protection status was not a significant predictor of either current benthic composition or changes in composition, but current cover and change in cover of several components were related to terrigenous content of sediment deposited recently. Sites with a higher proportion of terrigenous sediment had lower current coral cover, higher macroalgal cover and greater coral declines. Our results suggest that terrestrial sediment is an important factor in the recent degradation of coral reefs in Saint Lucia and that the current MPA network should be complemented by measures to reduce runoff from land.
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Affiliation(s)
- Chantale Bégin
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
- * E-mail:
| | - Christiane K. Schelten
- GEOMAR, Helmholtz Centre for Ocean Research Kiel, Düsternbrooker Weg 20, 24105, Kiel, Germany
| | - Maggy M. Nugues
- Laboratoire d’Excellence ‘CORAIL’ and USR 3278 CRIOBE EPHE-CNRS-UPVD, 58 Av. Paul Alduy, 66860 Perpignan Cedex, France
| | - Julie Hawkins
- Environment Department, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Callum Roberts
- Environment Department, University of York, Heslington, York, YO10 5DD, United Kingdom
| | - Isabelle M. Côté
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada
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Abstract
In 1983-1984, the sea urchin Diadema antillarum suffered mass mortality throughout the Caribbean, Florida, and Bermuda. The demise of this herbivore contributed to a phase shift of Caribbean reefs from coral-dominated to alga-dominated communities. A compilation of published data of D. antillarum population densities shows that there has been moderate recovery since 1983, with the highest rates on islands of the eastern Caribbean. On the average the current population densities are approximately 12% of those before the die-off, apparently because of recruitment limitation, but the exact factors that are constraining the recovery are unclear. Scattered D. antillarum cohorts in some localities and aggregation of settled individuals in shallow water have created zones of higher herbivory in which juvenile coral recruitment, survivorship, and growth are higher than they are in alga-dominated areas. Unlike other stressors on Caribbean coral reefs, recent changes in D. antillarum populations progress toward aiding the recovery of coral cover.
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Affiliation(s)
- H A Lessios
- Smithsonian Tropical Research Institute, Balboa, Panama;
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