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1.
Coral Reefs - Herbivorous fishes and urchins can contribute to reef resilience by removing algae that are competitive with corals, yet herbivorous fishes are frequently targeted by fishers. The... 相似文献
2.
Edward T. Game Michael Bode Eve McDonald-Madden Hedley S. Grantham Hugh P. Possingham 《Ecology letters》2009,12(12):1336-1346
Marine Protected Areas are usually static, permanently closed areas. There are, however, both social and ecological reasons to adopt dynamic closures, where reserves move through time. Using a general theoretical framework, we investigate whether dynamic closures can improve the mean biomass of herbivorous fishes on reef systems, thereby enhancing resilience to undesirable phase-shifts. At current levels of reservation (10–30%), moving protection between all reefs in a system is unlikely to improve herbivore biomass, but can lead to a more even distribution of biomass. However, if protected areas are rotated among an appropriate subset of the entire reef system (e.g. rotating 10 protected areas between only 20 reefs in a 100 reef system), dynamic closures always lead to increased mean herbivore biomass. The management strategy that will achieve the highest mean herbivore biomass depends on both the trajectories and rates of population recovery and decline. Given the current large-scale threats to coral reefs, the ability of dynamic marine protected areas to achieve conservation goals deserves more attention. 相似文献
3.
Coral reef marine protected areas (MPA) are widely distributed around the globe for social and ecological reasons. Relatively
few of these MPAs are well managed. This review examines the governance of coral reef MPAs and the means to improve coral
reef MPA management. It highlights common governance challenges, such as confused goals, conflict, and unrealistic attempts
to scale up beyond institutional capacity. Recommendations, based on field experience and empirical evidence from around the
world, are made for best practices at various stages of MPA implementation.
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A. T. WhiteEmail: |
4.
Dulvy NK 《Current biology : CB》2006,16(23):R989-R991
Populations of two coral reef shark species are declining rapidly: the pattern of decline highlights both the substantial impact of poaching on closed areas and the success of strict no-entry marine protected areas in maintaining healthy shark populations. 相似文献
5.
The effect of a marine protected area on the Lamellodiscus spp. monogenean community was tested by comparing the communities of parasites of Diplodus sargus inside and outside of the area. A total of 104 D. sargus were dissected harbouring 1280 monogeneans from the genus Lamellodiscus and belonging to 11 species. No modification in the global parasite community linked with the protection of the host populations was revealed. The most abundant and less specific parasite species, Lamellodiscus elegans , however, increased its abundance in the protected area. A significant relationship was found between parasite host range and the percentage of infected hosts. A significant relationship also occurred between epidemiological and genetic distances for the parasite species found. The results are discussed in term of parasite success and specificity and the importance of taking into account parasitism in the biological conservation of hosts. 相似文献
6.
Mark Westera Paul Lavery Glenn Hyndes 《Journal of experimental marine biology and ecology》2003,294(2):145-168
Many comparisons have been made between sanctuary (no-fishing) and fished areas, where fishing pressure is exerted by artisanal or commercial fishers, but few have examined the effect of recreational fishing on fish assemblages in coral reef habitats. In this study, we compared assemblages of targeted fish from coral reef habitats in sanctuary (no-fishing) and recreationally fished zones of a marine protected area (MPA). Surface visual census (SVC) transects were conducted two times, at three regions, to compare the composition of predatory fish assemblages and the abundance, biomass, and size of the most commonly targeted fish. Baited remote underwater video (BRUV) was used to make relative counts of fish between zones. We also measured benthic cover and rugosity, which may influence fish assemblages. Analysis of similarity (ANOSIM) revealed significant differences in the composition of fish families/genera targeted by fishers (Lethrinidae, Lutjanidae, Haemulidae, Serranidae, and the genus Choerodon of the family Labridae) in terms of biomass (P<0.01) and abundance (P<0.05). The most consistent trends were recorded for biomass and this was supported by clustering of replicates in nonmetric multidimensional scaling (nMDS) ordinations. Similarity percentages (SIMPER) analysis indicated that the family Lethrinidae accounted for 73% (as abundance), and up to 69% (as biomass), of the dissimilarity between zones. Three-factor ANOVA highlighted significantly greater biomass, size, and abundance of legal-sized lethrinids (the most targeted family in the region) in sanctuary zones, but no differences in other families/genera. Results of BRUV supported SVC with greater relative counts of lethrinids (P<0.01) in sanctuaries, but no significant differences for other families. Cover of Acropora coral and hard substrate differed between zones at some regions but differences were inconsistent. There were no significant differences in algal cover or rugosity between zones. Given the inconsistency in benthic cover, the similarity of rugosity between zones, the consistently greater biomass of lethrinids in sanctuaries, and the abundance of large lethrinids in sanctuaries, the cessation of fishing in sanctuary zones appears responsible for observed differences in the populations of these fish. These results demonstrate that recreational fishing pressure may be sufficient to deplete fish populations below that of adjacent protected areas and that the effect of recreational fishing in coral reef habitats may be greater than previously thought. 相似文献
7.
Climate warming, marine protected areas and the ocean-scale integrity of coral reef ecosystems 总被引:1,自引:0,他引:1
Graham NA McClanahan TR MacNeil MA Wilson SK Polunin NV Jennings S Chabanet P Clark S Spalding MD Letourneur Y Bigot L Galzin R Ohman MC Garpe KC Edwards AJ Sheppard CR 《PloS one》2008,3(8):e3039
Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef fish assemblages are the most species dense vertebrate communities on earth, contributing critical ecosystem functions and providing crucial ecosystem services to human societies in tropical countries. Our assessment of the impacts of the 1998 mass bleaching event on coral cover, reef structural complexity, and reef associated fishes spans 7 countries, 66 sites and 26 degrees of latitude in the Indian Ocean. Using Bayesian meta-analysis we show that changes in the size structure, diversity and trophic composition of the reef fish community have followed coral declines. Although the ocean scale integrity of these coral reef ecosystems has been lost, it is positive to see the effects are spatially variable at multiple scales, with impacts and vulnerability affected by geography but not management regime. Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change. 相似文献
8.
Marine Protected Areas (MPAs), if well designed and managed, can produce conservation benefits to fish assemblages within no-take zones and fishery benefits in neighboring areas through ‘spillover’. However, although plenty of studies have provided evidence of the benefits produced within MPA boundaries, overall benefits to local fisheries, especially via spillover, seem to be still unclear. Because of the lost fishing grounds following an MPA establishment, local fishermen usually oppose MPAs. There is, therefore, the urgent need for a better understanding of the mechanism(s) through which MPAs can export fishable fish biomass towards adjacent fished areas, a process that could counterbalance the loss of fishing grounds. Here we review the literature on spillover for refining the terminology, detailing the underlying mechanisms and identifying both the existing and needed methodological approaches to measure spillover. Operationally, two types of spillover should be considered: ecological spillover (i.e. the net export of juvenile, subadult and adult biomass from MPAs outwards driven by density-dependent processes) and the fishery spillover (i.e. the proportion of this biomass that can be fished, taking into account regulations and accessibility). Underwater visual census and tagging/tracking may allow getting evidence of ecological spillover, while experimental catch data are essential to assess and monitor fishery spillover, which is the main component of MPAs that can provide direct benefit to local fisheries. 相似文献
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12.
Tundi Agardy M 《Trends in ecology & evolution》1994,9(7):267-270
The world's oceans are now attracting the serious attention of conservationists. Paradoxically, as the value of marine biological diversity is recognized, the ecosystems that harbor this diversity are fast becoming degraded. New thinking about how to conserve coastal areas has resulted in protected-area models that incorporate principles of landscape ecology, adaptive and ecosystem management, and zoning in protected-area plans. 相似文献
13.
Carolina Camargo Jorge H. Maldonado Elvira Alvarado Rocío Moreno-Sánchez Sandra Mendoza Nelson Manrique Andrés Mogollón Juan D. Osorio Alejandro Grajales Juan Armando Sánchez 《Biodiversity and Conservation》2009,18(4):935-956
Climate change is posing new challenges to conservation because management policies on protected coral reefs are less effective
than they were before the current ecosystem degradation. Coral reefs, the most diverse and complex marine ecosystem provide
economic services for millions, but are seriously threatened worldwide because reef-building corals are experiencing bleaching
phenomena and a steady decline in abundance. The resources of a Marine Protected Area (MPA) in Cartagena, Colombia, are in
constant decline, despite a current management plan and on-site staff, urging new conservation actions. A multidisciplinary
team gathered to evaluate management effectiveness including biophysical, socioeconomic and governance indicators. Coral cover
and fish diversity and abundance were low both inside and outside the MPA, which suggests a limited efficiency of management.
Currently, the MPA is a reef with low coral cover and high algae cover as well as large dead coral areas, which are generally
signs of highly degraded reef habitats. Live coral cover in the MPA was represented by pioneer coral species such as Agaricia tenuifolia and Porites astreoides. Nonetheless, 35% of the scleractinian species sampled in the area harbored more than one zooxanthellae symbiont, which suggests
potential resistance and resilience against coral bleaching. Maintenance of trophic structure and functional diversity is
an important endeavor that should be a priority for management in order to allow ecosystem resilience. Social and governance
indicators showed low-income levels and few opportunities for communities living in and around the park, low governability,
weak communication among stakeholders and with authorities at different levels. As a result, problems related to over exploitation
of resources were commonplace in the MPA. These results reflect low adaptive capacity of communities to comply with restrictive
conservation rules, showing that establishment of a protected area is a necessary but insufficient condition to guarantee
conservation goals. Ignoring the role of local communities only will exacerbate the problems associated with natural resources.
Involvement of communities in strategic ecosystems management appears to be a requisite to improve effectiveness of protected
areas, and participatory strategies, such as co-management, offer opportunities to improve governability while letting communities
adapt to MPA needs. 相似文献
14.
Many estimates of ‘marine protected area (MPA) effects’ may be confounded by environmental heterogeneity between MPA and ‘Control’
sites. However, the magnitude and extent of such confounding is generally unknown. Here, the effects of microhabitat availability
on estimates of MPA performance were explicitly explored. Abundance of a reef fish species, Ctenochaetus striatus (Quoy & Gaimard, 1825), available microhabitat, and, microhabitat preference for C. striatus within six ‘Ra’ui’ (traditionally managed MPAs) and six paired ‘Control’ sites on the island of Rarotonga, Cook Islands,
were estimated. Response ratios accounting for available microhabitat qualitatively modified inferences of Ra’ui effectiveness
for two of the six Ra’ui when contrasted with response ratios not accounting for available microhabitat. However, analysis
of covariance (ANCOVA) indicated that available microhabitat accounted for significant variation in C. striatus densities between Ra’ui and Control, rather than protection. Our results suggest that adjusting for microhabitat availability
may significantly alter our perception of the effects of Ra’ui on C. striatus. Our framework, in concert with our ANCOVA models, provides a stronger assessment of MPA effects. Further, we conclude that
metrics of environmental heterogeneity should be incorporated into future assessments of MPA effectiveness, with our work
describing one potential framework to accomplish this. 相似文献
15.
Connectivity and resilience of coral reef metapopulations in marine protected areas: matching empirical efforts to predictive needs 总被引:1,自引:1,他引:1
Botsford LW White JW Coffroth MA Paris CB Planes S Shearer TL Thorrold SR Jones GP 《Coral reefs (Online)》2009,28(2):327-337
Design and decision-making for marine protected areas (MPAs) on coral reefs require prediction of MPA effects with population
models. Modeling of MPAs has shown how the persistence of metapopulations in systems of MPAs depends on the size and spacing
of MPAs, and levels of fishing outside the MPAs. However, the pattern of demographic connectivity produced by larval dispersal
is a key uncertainty in those modeling studies. The information required to assess population persistence is a dispersal matrix
containing the fraction of larvae traveling to each location from each location, not just the current number of larvae exchanged
among locations. Recent metapopulation modeling research with hypothetical dispersal matrices has shown how the spatial scale
of dispersal, degree of advection versus diffusion, total larval output, and temporal and spatial variability in dispersal
influence population persistence. Recent empirical studies using population genetics, parentage analysis, and geochemical
and artificial marks in calcified structures have improved the understanding of dispersal. However, many such studies report
current self-recruitment (locally produced settlement/settlement from elsewhere), which is not as directly useful as local
retention (locally produced settlement/total locally released), which is a component of the dispersal matrix. Modeling of
biophysical circulation with larval particle tracking can provide the required elements of dispersal matrices and assess their
sensitivity to flows and larval behavior, but it requires more assumptions than direct empirical methods. To make rapid progress
in understanding the scales and patterns of connectivity, greater communication between empiricists and population modelers
will be needed. Empiricists need to focus more on identifying the characteristics of the dispersal matrix, while population
modelers need to track and assimilate evolving empirical results. 相似文献
16.
Safra Altman Robert B. Whitlatch 《Journal of experimental marine biology and ecology》2007,342(1):15-29
Introductions of non-indigenous species have resulted in many ecological problems including the reduction of biodiversity, decline of commercially important species and alteration of ecosystems. The link between disturbance and invasion potential has rarely been studied in the marine environment where dominance hierarchies, dynamics of larval supply, and resource acquisition may differ greatly from terrestrial systems. In this study, hard substrate marine communities in Long Island Sound, USA were used to assess the effect of disturbance on resident species and recent invaders, ascidian growth form (i.e. colonial and solitary growth form), and the dominant species-specific responses within the community. Community age was an additional factor considered through manipulation of 5-wk old assemblages and 1-yr old assemblages. Disturbance treatments, exposing primary substrate, were characterized by frequency (single, biweekly, monthly) and magnitude (20%, 48%, 80%) of disturbance. In communities of different ages, disturbance frequency had a significant positive effect on space occupation of recent invaders and a significant negative effect on resident species. In the 5-wk community, magnitude of disturbance also had a significant effect. Disturbance also had a significant effect on ascidian growth form; colonial species occupied more primary space than controls in response to increased disturbance frequency and magnitude. In contrast, solitary species occupied significantly less space than controls. Species-specific responses were similar regardless of community age. The non-native colonial ascidian Diplosoma listerianum responded positively to increased disturbance frequency and magnitude, and occupied more primary space in treatments than in controls. The resident solitary ascidian Molgula manhattensis responded negatively to increased disturbance frequency and magnitude, and occupied less primary space in treatments than in controls. Small-scale biological disturbances, by creating space, may facilitate the success of invasive species and colonial organisms in the development of subtidal hard substrate communities. 相似文献
17.
John W. Turnbull Yasmina Shah Esmaeili Graeme F. Clark Will F. Figueira Emma L. Johnston Renata Ferrari 《Biodiversity and Conservation》2018,27(9):2217-2242
Marine Protected Areas (MPAs) are a key management tool for the conservation of biodiversity and restoration of marine communities. While large, well-designed and enforced MPAs have been found to be effective, results from small MPAs vary. The Hawkesbury Shelf, a coastal bioregion in New South Wales, Australia, has ten small, near-shore MPAs known as Aquatic Reserves with a variety of protection levels from full no-take to partial protection. This study assessed the effectiveness of these MPAs and analysed how MPA age, size, protection level, wave exposure, habitat complexity, and large canopy-forming algal cover affected fish, invertebrate and benthic communities. We found aspect, protection level, complexity and algal canopy to be important predictors of communities in these MPAs. Most MPAs, however, were not effective in meeting their goals. Only full no-take protection (three out of ten MPAs) had a significant impact on fish assemblages. One no-take MPA—Cabbage Tree Bay—which is naturally sheltered from wave action and benefits from an active local community providing informal enforcement, accounted for most of the increased richness of large fish and increased biomass of targeted fish species. Our findings suggest that small MPAs can enhance biodiversity and biomass on a local scale but only if they have full no-take protection, are in sheltered locations with complex habitat, and have positive community involvement to engender support and stewardship. These results provide a baseline for robust assessment of the effectiveness of small MPAs and inform future management decisions and small MPA design in other locations. 相似文献
18.
Marine reserves are widely implemented worldwide to meet both conservation and fisheries management goals. This study examines
the efficacy of Philippine marine reserves using meta-analysis by comparing variations in fish density (1) between reserves
and adjacent fished reefs (spatial comparison), (2) within reserves before establishment relative to years following the establishment
(temporal comparison), and (3) among reserves classified based on size, age, and enforcement capacity. A grand (total) mean
of nineteen 22.3 ha coral reef reserves, protected for a mean duration of 8.2 years, were included in the meta-analyses. The
overall density of fishes was higher in the reserves compared with the fished reefs and this difference was largely accounted
for by exploited fishes. However, the overall density of fishes within the same reserves remained similar from the period
before its establishment to several years following its establishment. Only the density of nonexploited fishes increased significantly
during years subsequent to the establishment of the reserves. Neither age nor size of reserves correlated with pattern of
change in fish density following the establishment of the reserves; however, fish density was consistently higher in larger
and older reserves relative to smaller and younger reserves in the spatial comparison. Furthermore, well-enforced reserves
had higher density of exploited fishes relative to less-enforced reserves in both spatial and temporal comparisons. In general,
the magnitude and trajectory of change in fish density following the establishment of Philippine marine reserves are influenced
by (1) functional groups of fishes under consideration, (2) size and age of the reserve, and (3) level of enforcement of the
regulatory mechanisms necessary to sustain a marine reserve. 相似文献
19.
Abner A. Bucol Rene A. Abesamis Brian L. Stockwell Jake R. Lowe Garry R. Russ 《Journal of fish biology》2021,99(5):1561-1575
Empirical evidence for increases in the reproductive potential (egg output per unit area) of coral reef fish in no-take marine reserves (NTMRs) is sparse. Here, we inferred the development of reproductive potential in two species of protogynous reef fishes, Chlorurus bleekeri (Labridae: Scarinae) and Cephalopholis argus (Epinephelidae), inside and outside of Philippine NTMRs. We estimated key reproductive parameters and applied these to species-specific density and length data from 17 NTMRs (durations of protection 0–11 years) and paired fished sites (controls) in a space-for-time substitution approach. For C. argus, we also used density and length data collected almost annually over 29 years from a NTMR and an adjacent control at Apo Island. The results suggest that C. bleekeri can develop 6.0 times greater reproductive potential in NTMRs than controls after 11 years of protection, equivalent to approximately 582,000 more eggs produced 500 m−2 inside NTMRs. Enhancement of reproductive potential in C. argus was not evident after 11 years in the space-for-time substitution. At Apo Island NTMR, reproductive potential of C. argus increased approximately 6-fold over 29 years but NTMR/control ratios in reproductive potential decreased through time (from 3.2 to 2.4), probably due to spillover of C. argus from the NTMR to the control. C. argus was estimated to produce approximately 113,000 more eggs 500 m−2 inside Apo Island NTMR at the 29th year of protection. Ratios of reproductive potential between NTMR and controls in C. bleekeri and C. argus were often greater than corresponding ratios in density or biomass. The study underscores the importance of species-specific reproductive life history traits that drive variation in the development of larval fish subsidies that originate from NTMRs. 相似文献
20.
Borie-Mojica Alfredo Rezende Sergio Magalhães Padovani Ferreria Beatrice Maida Mauro Travassos Paulo 《Environmental Biology of Fishes》2022,105(5):575-587
Environmental Biology of Fishes - This study implemented Passive Acoustic Monitoring (PAM) to evaluate temporal acoustic patterns in a protected coastal reef area in Tamandaré beach... 相似文献