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Linking Ecological and Perceptual Assessments for Environmental Management: a Coral Reef Case Study
Elizabeth A. Dinsdale
Ecology and Society , 2009,
Abstract: Integrating information from a range of community members in environmental management provides a more complete assessment of the problem and a diversification of management options, but is difficult to achieve. To investigate the relationship between different environmental interpretations, I compared three distinct measures of anchor damage on coral reefs: ecological measures, perceptual meanings, and subjective health judgments. The ecological measures identified an increase in the number of overturned corals and a reduction in coral cover, the perceptual meanings identified a loss of visual quality, and the health judgments identified a reduction in the health of the coral reef sites associated with high levels of anchoring. Combining the perceptual meanings and health judgments identified that the judgment of environmental health was a key feature that both scientific and lay participants used to describe the environment. Some participants in the survey were familiar with the coral reef environment, and others were not. However, they provided consistent judgment of a healthy coral reef, suggesting that these judgments were not linked to present-day experiences. By combining subjective judgments and ecological measures, the point at which the environment is deemed to lose visual quality was identified; for these coral reefs, if the level of damage rose above 10.3% and the cover of branching corals dropped below 17.1%, the reefs were described as unhealthy. Therefore, by combining the information, a management agency can involve the community in identifying when remedial action is required or when management policies are effectively maintaining a healthy ecosystem.
Human Dimensions of Coral Reef Social-Ecological Systems  [cached]
John N. Kittinger,Elena M. Finkbeiner,Edward W. Glazier,Larry B. Crowder
Ecology and Society , 2012, DOI: 10.5751/es-05115-170417
Abstract: Coral reefs are among the most diverse ecosystems on the planet but are declining because of human activities. Despite general recognition of the human role in the plight of coral reefs, the vast majority of research focuses on the ecological rather than the human dimensions of reef ecosystems, limiting our understanding of social relationships with these environments as well as potential solutions for reef recovery. General frameworks for social-ecological systems (SESs) have been advanced, but system-specific approaches are needed to develop a more nuanced view of human-environmental interactions for specific contexts and resource systems, and at specific scales. We synthesize existing concepts related to SESs and present a human dimensions framework that explores the linkages between social system structural traits, human activities, ecosystem services, and human well-being in coral reef SESs. Key features of the framework include social-ecological reciprocity, proximate and underlying dimensions, and the directionality of key relationships and feedback loops. Such frameworks are needed if human dimensions research is to be more fully integrated into studies of ecosystem change and the sustainability of linked SESs.
Coral Reef Resilience through Biodiversity  [PDF]
Caroline S. Rogers
ISRN Oceanography , 2013, DOI: 10.5402/2013/739034
Abstract: Irrefutable evidence of coral reef degradation worldwide and increasing pressure from rising seawater temperatures and ocean acidification associated with climate change have led to a focus on reef resilience and a call to “manage” coral reefs for resilience. Ideally, global action to reduce emission of carbon dioxide and other greenhouse gases will be accompanied by local action. Effective management requires reduction of local stressors, identification of the characteristics of resilient reefs, and design of marine protected area networks that include potentially resilient reefs. Future research is needed on how stressors interact, on how climate change will affect corals, fish, and other reef organisms as well as overall biodiversity, and on basic ecological processes such as connectivity. Not all reef species and reefs will respond similarly to local and global stressors. Because reef-building corals and other organisms have some potential to adapt to environmental changes, coral reefs will likely persist in spite of the unprecedented combination of stressors currently affecting them. The biodiversity of coral reefs is the basis for their remarkable beauty and for the benefits they provide to society. The extraordinary complexity of these ecosystems makes it both more difficult to predict their future and more likely they will have a future. 1. Introduction Increasing concern over worldwide deterioration of coral reefs and the likelihood that global climate change will cause further degradation has led to a focus on the concept of reef resilience. Local, regional, and global stressors have the potential to cause irreversible losses of biodiversity in some reefs and consequently of the ecosystem services they provide [1–9]. Even the physical structure of some coral reefs may be in jeopardy. Can these reefs recover and persist? Can they be managed for resilience? The future of many reefs will depend on whether fundamental processes like photosynthesis, calcification, and recruitment can continue in the face of a multitude of local and global stressors. Reefs that previously could recover after a disturbance may not be able to survive the assaults of global climate change, especially when combined with local pressures. The limits of our current knowledge of the biodiversity of coral reefs, of the potential for corals and other reef species to adapt to climate change, and of the effects of increasing sea water temperatures, ocean acidification, and other components of climate change on reef organisms make it challenging to predict what the future holds
Habitat Associations of Juvenile Fish at Ningaloo Reef, Western Australia: The Importance of Coral and Algae  [PDF]
Shaun K. Wilson,Martial Depczynski,Rebecca Fisher,Thomas H. Holmes,Rebecca A. O'Leary,Paul Tinkler
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0015185
Abstract: Habitat specificity plays a pivotal role in forming community patterns in coral reef fishes, yet considerable uncertainty remains as to the extent of this selectivity, particularly among newly settled recruits. Here we quantified habitat specificity of juvenile coral reef fish at three ecological levels; algal meadows vs. coral reefs, live vs. dead coral and among different coral morphologies. In total, 6979 individuals from 11 families and 56 species were censused along Ningaloo Reef, Western Australia. Juvenile fishes exhibited divergence in habitat use and specialization among species and at all study scales. Despite the close proximity of coral reef and algal meadows (10's of metres) 25 species were unique to coral reef habitats, and seven to algal meadows. Of the seven unique to algal meadows, several species are known to occupy coral reef habitat as adults, suggesting possible ontogenetic shifts in habitat use. Selectivity between live and dead coral was found to be species-specific. In particular, juvenile scarids were found predominantly on the skeletons of dead coral whereas many damsel and butterfly fishes were closely associated with live coral habitat. Among the coral dependent species, coral morphology played a key role in juvenile distribution. Corymbose corals supported a disproportionate number of coral species and individuals relative to their availability, whereas less complex shapes (i.e. massive & encrusting) were rarely used by juvenile fish. Habitat specialisation by juvenile species of ecological and fisheries importance, for a variety of habitat types, argues strongly for the careful conservation and management of multiple habitat types within marine parks, and indicates that the current emphasis on planning conservation using representative habitat areas is warranted. Furthermore, the close association of many juvenile fish with corals susceptible to climate change related disturbances suggests that identifying and protecting reefs resilient to this should be a conservation priority.
ASSESSING ECOLOGICAL RESILIENCE OF INDONESIAN CORAL REEFS  [cached]
Imam Bachtiar1,2, Ario Damar1, Suharsono3, Neviaty P. Zamani4
Journal of Coastal Development , 2011,
Abstract: Ecological resilience is an important property of natural ecosystem to be understood in coral reef management. Resilience of Indonesian coral reefs was assessed using 2009 COREMAP data. The assessment used 698 data of line intercept transects collected from 15 districts and 4 marine physiographies. Resilience index used in the assessment was developed by the authors but will be published elsewhere. The results showed that coral reefs at western region had higher average resilience indices than eastern region, and Sunda Shelf reefs had higher resilience indices than coral reefs at Indian Ocean, Sulawesi-Flores, or Sahul Shelf. Four districts were found to have coral reefs with highest resilience indices, i.e. Bintan and Natuna (western region), and Wakatobi and Buton (eastern region). Raja Ampat had coral reefs with lower average resilience indices than that of Wakatobi. Uses of resilience index in coral reef management should be coupled with other information such as maximum depth of coral communities.
Coral Reef Monitoring: From Cytological Parameters to Community Indices  [PDF]
Ofer Ben-Tzvi,Mohammad Al-Zibdah,Vladimir Bresler,Yousef Jamal,Avigdor Abelson
Journal of Marine Biology , 2011, DOI: 10.1155/2011/151268
Abstract: Sound-ecosystem-based management of coral reefs is largely based on indicators of reef health state. Currently there are various ecological parameters that serve as reef state indices; however, their practical implications are under debate. In the present study we examine an alternative parameter, the deterioration index (DI), which does not purport to replace the traditional indices but can provide a reliable, stand-alone indication of reef state. Patterns of cytological indices, which are considered as reliable indicators of environmental stressors, have been compared to ten selected reef community indices. The DI showed the highest correlations among community indices to the cytological indices in artificial reefs and high correlation in natural reefs as well. Our results suggest that in cases of lacking adequate monitoring abilities where a full set of community indices cannot be obtained, the DI can serve in many cases as the preferred, stand-alone indicator of coral reef state. 1. Introduction Coral reefs are in serious decline worldwide [1, 2], and concerns for the future existence of the reefs have driven governments, international organizations, and NGOs to seek ways to prevent or mitigate the degradation of these essential ecosystems. A crucial element of coral reef protection and management is efficient and reliable monitoring; a critical tool for identification of reef deterioration, its causes, and countermeasures. At present, there are various monitoring methods that employ diverse indices of coral reef state (e.g., live cover, species diversity, key species abundances (for more details, see [3, 4])). However, many coral reef ecologists have raised doubts about the usefulness and reliability of the commonly used community parameters (in expressing the actual state of reefs (e.g., [5–9])). These doubts are derived from two major factors: first, the high complexity and natural variability of reef communities and, second, the strong dependency of acquiring reliable reef-state indications on long-term, expensive, and complicated monitoring, which includes assessment of diverse community variables (e.g., [10]). It should be stressed that most of the common indices, if examined repeatedly at the same site over several years, indeed provide reliable indications of trends of the coral community state (e.g., [10–13]). However, given the above noted limitations, long-term monitoring programs that include a wide range of community indices are rare. On the other hand, none of the traditional indices can stand alone as a reliable indication of reef
The Ecology of Coral Reef Top Predators in the Papahānaumokuākea Marine National Monument  [PDF]
Jonathan J. Dale,Carl G. Meyer,Christian E. Clark
Journal of Marine Biology , 2011, DOI: 10.1155/2011/725602
Abstract: Coral reef habitats in the Papahānaumokuākea Marine National Monument (PMNM) are characterized by abundant top-level predators such as sharks and jacks. The predator assemblage is dominated both numerically and in biomass by giant trevally (Caranx ignobilis) and Galapagos sharks (Carcharhinus galapagensis). A lower diversity of predatory teleosts, particularly groupers and snappers, distinguishes the PMNM from other remote, unfished atolls in the Pacific. Most coral reef top predators are site attached to a “home” atoll, but move extensively within these atolls. Abundances of the most common sharks and jacks are highest in atoll fore reef habitats. Top predators within the PMNM forage on a diverse range of prey and exert top-down control over shallow-water reef fish assemblages. Ecological models suggest ecosystem processes may be most impacted by top predators through indirect effects of predation. Knowledge gaps are identified to guide future studies of top predators in the PMNM. 1. Introduction Large predators are becoming scarce on many coral reefs, with fishing thought to be a major factor in declines [1–7]. Coral reef top predators often command high market prices, providing strong economic incentives for commercial harvesting [8, 9]. Major contributors to commercial overharvesting of coral reef predators include the shark fin fishery [8, 10–12] and the live reef food fish trade [9, 13]. Consequently, intensive commercial exploitation has resulted in dramatic declines in reef predators in many locations [4, 13], and recent studies suggest even subsistence fishing can deplete reef predators [2, 5, 6]. Although less clear cut than in terrestrial systems (e.g., [14, 15]), there is growing evidence that removal of top predators from marine ecosystems may trigger trophic cascades resulting in phase shifts [2, 6, 16–19]. In coral reef ecosystems, these shifts appear to favor algal-dominated reefs populated by small planktivorous fishes and echinoderms, at the expense of reef-building scleractinian corals [2, 6, 16, 19]. Collectively these studies indicate that effective conservation of top level predators is important for coral reef ecosystem health. Science-based management and effective conservation of coral reef top predators requires a broad understanding of their ecology. We need to know which species are present, their abundance, spatial dynamics and habitat requirements, rates of growth, reproduction and mortality, diet, and ecological interactions with other species. Unfortunately, the natural ecology of top predators has already been
Evaluating Social and Ecological Vulnerability of Coral Reef Fisheries to Climate Change  [PDF]
Joshua E. Cinner, Cindy Huchery, Emily S. Darling, Austin T. Humphries, Nicholas A. J. Graham, Christina C. Hicks, Nadine Marshall, Tim R. McClanahan
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074321
Abstract: There is an increasing need to evaluate the links between the social and ecological dimensions of human vulnerability to climate change. We use an empirical case study of 12 coastal communities and associated coral reefs in Kenya to assess and compare five key ecological and social components of the vulnerability of coastal social-ecological systems to temperature induced coral mortality [specifically: 1) environmental exposure; 2) ecological sensitivity; 3) ecological recovery potential; 4) social sensitivity; and 5) social adaptive capacity]. We examined whether ecological components of vulnerability varied between government operated no-take marine reserves, community-based reserves, and openly fished areas. Overall, fished sites were marginally more vulnerable than community-based and government marine reserves. Social sensitivity was indicated by the occupational composition of each community, including the importance of fishing relative to other occupations, as well as the susceptibility of different fishing gears to the effects of coral bleaching on target fish species. Key components of social adaptive capacity varied considerably between the communities. Together, these results show that different communities have relative strengths and weaknesses in terms of social-ecological vulnerability to climate change.
Behavior of Dissolved Organic Matter in Coral Reef Waters in Relation with Biological Processes  [cached]
Mohamed Farook Mohamed Fairoz,Beatriz E. Casareto,Yoshimi Suzuki
Modern Applied Science , 2011, DOI: 10.5539/mas.v5n1p3
Abstract: Behavior of dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in coral reef waters in relation with biological processes was studied with incubation experiments and field observations in May 2008 and 2009 at the fringing reef of Sesoko Island, Okinawa, Japan. Reef sea water (RSW) and coral mucus added RSW collected from Acropora digitifera (AcrRSW) and Montipora digitata (MonRSW) were incubated for one day in situ and then for 77 days in the laboratory under dark condition. The results indicated that the behavior of DON was different compared to that of DOC in RSW and mucus added (AcrRSW and MonRSW) during dark incubation. Concentration of DON increased from 8.3 μM to 11.8 μM for AcrRSW and 4.0 μM to 15.4 μM for MonRSW during dark incubation period. The increasing rates for DON in AcrSRW and MonRSW were 0.05 μM day-1 and 0.1 μM day-1 respectively. On the other hand DOC concentration decreased from 129.0 μM to 75.0 μM for AcrRSW and 75.1 μM to 64.7 μM for MonRSW, with decreasing rates of 0.7 μM day-1 and 0.1 μM day-1 respectively. We assume that the increase of DON may be determined by difference between rates of inputs of organic matter mainly from mucus and rate of degradation of dissolved organic matter in the water column. These results suggest that recycling of DON is slow than that of DOC in coral reef ecosystem.
Periodic Closures as Adaptive Coral Reef Management in the Indo-Pacific  [cached]
Josh Cinner,Michael J. Marnane,Timothy R. McClanahan,Glenn R. Almany
Ecology and Society , 2006,
Abstract: This study explores the social, economic, and ecological context within which communities in Papua New Guinea and Indonesia use adaptive coral reef management. We tested whether periodic closures had positive effects on reef resources, and found that both the biomass and the average size of fishes commonly caught in Indo-Pacific subsistence fisheries were greater inside areas subject to periodic closures compared to sites with year-round open access. Surprisingly, both long-lived and short-lived species benefited from periodic closures. Our study sites were remote communities that shared many socioeconomic characteristics; these may be crucial to the effectiveness of adaptive management of reef resources through periodic closures. Some of these factors include exclusive tenure over marine resources, a body of traditional ecological knowledge that allows for the rapid assessment of resource conditions, social customs that facilitate compliance with closures, relatively small human populations, negligible migration, and a relatively low dependence on fisheries. This dynamic adaptive management system, in which communities manage their resources among multiple social and ecological baselines, contrasts with western fisheries management practices, centered on maintaining exploited populations at stable levels in which net production is maximized.
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