Assessment Assessment of benthic and coral community structure in an inshore reef in Balok, Pahang, Malaysia

AbstractSubtropical reefs are unique ecosystems that require effective management – informed by regular ecological monitoring – to foster resilience to environmental changes. Resources to conduct monitoring are limited, and citizen science can complement data from local management agencies. Here, citizen science efforts document the ecological status of a subtropical reef, Flinders Reef, Moreton Bay Marine Park, Australia. Ecological surveys, following Reef Check Australia and CoralWatch protocols, were conducted by 44 trained volunteers. Ten sites at Flinders Reef were surveyed at 5-10 m depth in autumn and spring. Additionally, underwater photos and depth surveys were integrated with satellite imagery to create a detailed habitat map. Coral cover across sites ranged between 14% and 67%. Branching corals dominated the site with 67% cover and showed 89% dissimilarity in coral community composition compared to other sites. Coral community composition was mostly explained by spatial variation, of which 16% was influenced by wave exposure. Observed reef impacts including physical damage, unknown scars and coral disease were three times lower than studies on more accessible reefs in Moreton Bay Marine Park. Invertebrate abundance was relatively low (6.65 individuals per 100 m2), with the most abundant groups observed being sea urchins (Diademaspp.), gastropods (Drupellaspp.) and anemones. Butterflyfish were recorded at every site and were the most abundant fish group surveyed. Findings highlight the healthy condition of Flinders Reef, likely influenced by its offshore location and protection status as a ‘no-take’ zone. This study demonstrates that increasing the current 500m radius protection zone by a further 500m could double the protected area of coral, offering potential further conservation benefits. The findings resulting from the ecological data analysis and created benthic habitat map, provide an example of how citizen science based projects can assist marine park authorities and the public in ongoing conservation efforts.

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Coral communities condition in varying wave exposure: the gulf of Cazones, Cuba

Revista de Biología Tropical ◽

10.15517/rbt.v64i1.18231 ◽

2016 ◽

Vol 64 (1) ◽

pp. 79 ◽

Cited By ~ 3

Author(s):

Hansel Caballero Aragon ◽

Pedro M Alcolado ◽

Néstor Rey-Villiers ◽

Susana Perera Valderrama ◽

Juliett González Méndez

Keyword(s):

Species Richness ◽

Community Structure ◽

Marine Protected Area ◽

Coral Cover ◽

Coral Community ◽

Wave Exposure ◽

Maximum Diameter ◽

Live Coral ◽

Coral Mortality ◽

Coral Communities

Wave exposure can influence community structure and distribution of shallow coral reefs, by affecting organisms both directly and indirectly. To assess the current stony coral community condition under different degrees of wave exposure at a marine protected area of the Gulf of Cazones (SW Cuba), two expeditions were carried out in May 2010 and June 2012. Four sampling sites were sampled at reef crests (1.5 m deep), and twelve at fore-reefs, at 10, 15 and 20 m deep in four geographic locations. Live coral cover, species richness and composition, colony density, and maximum diameter were assessed using the AGRRA 2001 methodology. Multivariate and non-parametric statistics were applied to compare sites. The coral community structure within reef crests was not homogenous. The observed variability of indicators apparently was determined by great coral mortality events resulting from natural disturbances that occurred in the past (hurricanes, bleaching and diseases). Fore-reef coral communities displayed better condition and lower coral mortality than reef crests. Species richness and coral composition varied, while multivariate and statistical methods did not reveal site grouping with regard to wave exposure. The remaining biological condition indicators were similar among sites, except in the most exposed one, where coral cover and coral size were slightly lower. Wave exposure in the gulf of Cazones seemed not to have a significant influence on differences in condition and structure of the assessed coral communities.

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Coral community bleaching response on a highly urbanised reef

10.7287/peerj.preprints.760 ◽

2014 ◽

Author(s):

James R Guest ◽

Jeffrey Low ◽

Karenne Tun ◽

Jani I Tanzil ◽

Peter A Todd ◽

...

Keyword(s):

Community Structure ◽

Thermal Stress ◽

Anthropogenic Impacts ◽

Coral Cover ◽

Regional Scale ◽

Coral Community ◽

Bleaching Response ◽

Sea Surface Temperature Anomalies ◽

Relative Cover ◽

June July

Projected increases in the magnitude and frequency of sea surface temperature anomalies present a significant threat to the persistence of tropical coral reefs, however, detailed studies of community level responses to thermal stress are needed if its effect on reef resilience are to be understood. While many studies report on broad, regional scale responses to thermal stress (e.g., proportion of corals bleached), far fewer examine variation in susceptibility among taxa and change in coral community structure, before, during and after bleaching on individual reefs. Furthermore, relatively few studies of bleaching response come from highly urbanised reefs that experience chronic disturbances such as elevated sedimentation and turbidity. Here we report in detail on the bleaching response of corals at a highly urbanised reef site south of mainland Singapore during (June, July) and immediately after (October) a major thermal coral bleaching event in 2010. To estimate the capacity for resistance and resilience to thermal stress, we report on a) the overall bleaching severity during and after the event, b) differences in bleaching susceptibility among taxa during the event and c) the response of the reef in terms of taxonomic community structure before (2009) and after (2012) bleaching. Despite severe bleaching in 2010 (66% of colonies bleached), post-bleaching recovery appeared to be relatively rapid and coral taxa that are usually highly susceptible (e.g., Acropora and Pocillopora) were relatively unaffected, i.e., either they did not bleach or they bleached and recovered. Although there was no significant change in coral taxonomic community structure among years, taxa that bleached most severely tended to have the greatest reductions in relative cover. Several factors may have contributed to the overall high resistance of this site to bleaching including turbidity, symbiont affiliation and heterotrophy. A parsimonious explanation for the reversed pattern of bleaching susceptibility among taxa is that these coral populations have adapted and/or acclimatised to thermal stress. Despite ongoing chronic anthropogenic impacts, we suggest that this site has potential for rapid recovery of coral cover due to the dominant coral taxa and growth forms being capable of rapid regrowth from remnant colonies.

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Functional consequences of the long-term decline of reef-building corals in the Caribbean: evidence of across-reef functional convergence

Royal Society Open Science ◽

10.1098/rsos.190298 ◽

2019 ◽

Vol 6 (10) ◽

pp. 190298 ◽

Cited By ~ 9

Author(s):

Nuria Estrada-Saldívar ◽

Eric Jordán-Dalhgren ◽

Rosa E. Rodríguez-Martínez ◽

Chris Perry ◽

Lorenzo Alvarez-Filip

Keyword(s):

Community Composition ◽

Coral Species ◽

Coral Cover ◽

Coral Community ◽

Back Reef ◽

Anthropogenic Pressures ◽

Carbonate Production ◽

Fore Reef ◽

Functional Integrity ◽

Reef Zones

Functional integrity on coral reefs is strongly dependent upon coral cover and coral carbonate production rate being sufficient to maintain three-dimensional reef structures. Increasing environmental and anthropogenic pressures in recent decades have reduced the cover of key reef-building species, producing a shift towards the relative dominance of more stress-tolerant taxa and leading to a reduction in the physical functional integrity. Understanding how changes in coral community composition influence the potential of reefs to maintain their physical reef functioning is a priority for their conservation and management. Here, we evaluate how coral communities have changed in the northern sector of the Mexican Caribbean between 1985 and 2016, and the implications for the maintenance of physical reef functions in the back- and fore-reef zones. We used the cover of coral species to explore changes in four morpho-functional groups, coral community composition, coral community calcification, the reef functional index and the reef carbonate budget. Over a period of 31 years, ecological homogenization occurred between the two reef zones mostly due to a reduction in the cover of framework-building branching ( Acropora spp.) and foliose-digitiform ( Porites porites and Agaricia tenuifolia ) coral species in the back-reef, and a relative increase in non-framework species in the fore-reef ( Agaricia agaricites and Porites astreoides ). This resulted in a significant decrease in the physical functionality of the back-reef zone. At present, both reef zones have negative carbonate budgets, and thus limited capacity to sustain reef accretion, compromising the existing reef structure and its future capacity to provide habitat and environmental services.

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Impacts of Stony Coral Tissue Loss Disease (SCTLD) on Coral Community Structure at an Inshore Patch Reef of the Upper Florida Keys Using Photomosaics

Frontiers in Marine Science ◽

10.3389/fmars.2021.682163 ◽

2021 ◽

Vol 8 ◽

Author(s):

Graham Kolodziej ◽

Michael S. Studivan ◽

Arthur C. R. Gleason ◽

Chris Langdon ◽

Ian C. Enochs ◽

...

Keyword(s):

Community Structure ◽

Coral Reef ◽

Coral Cover ◽

Florida Keys ◽

Coral Community ◽

Tissue Loss ◽

Coral Tissue ◽

Coral Mortality ◽

Stony Coral ◽

Reef Tract

Since the appearance of stony coral tissue loss disease (SCTLD) on reefs off Miami in 2014, this unprecedented outbreak has spread across the entirety of Florida’s coral reef tract, as well as to many territories throughout the Caribbean. The endemic zone reached the upper Florida Keys by 2016, resulting in partial or complete mortality of coral colonies across numerous species. Disease was first observed at Cheeca Rocks (Islamorada, Florida) in the beginning of 2018, with reports of coral mortality peaking mid-year. The disease was still present at Cheeca Rocks as of March 2020, however, to a lesser degree compared to the initial outbreak. Annual monitoring efforts have been ongoing at Cheeca Rocks since 2012, including repeated benthic photomosaics of a 330 m2 survey zone, spanning six replicate sites. As such, a repository of coral community composition data exists for before and after the disease outbreak that was analyzed to assess the impacts of SCTLD on reef communities at an upper Florida Keys inshore reef. Cheeca Rocks is hypothesized to be a resilient reef due to its persistent high coral cover despite its inshore location, which subjects corals to fluctuating water quality and marginal environmental conditions. Coral populations here have been shown to recover from bleaching events and heat stress with minimal coral mortality. Though colonies of coral species characterized as highly and moderately susceptible to SCTLD (e.g., Colpophyllia natans, Diploria labyrinthiformis, Pseudodiploria strigosa, Orbicella annularis, and O. faveolata) suffered mortality as a result of the outbreak with an average loss of 16.42% relative cover by species, the overall impacts on coral cover and community structure were relatively low, contributing to a loss of total coral cover of only 1.65%. Comparison of photomosaic data to other studies indicate Cheeca Rocks may not have been affected as severely as other sites on Florida’s coral reef tract, underlying this site’s potential role in coral resilience to stressors including bleaching events, land-based pollution, and disease epizootics.

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Spatial Patterns of Coral Community Structure in the Toliara Region of Southwest Madagascar and Implications for Conservation and Management

Diversity ◽

10.3390/d13100486 ◽

2021 ◽

Vol 13 (10) ◽

pp. 486

Author(s):

Radonirina Lebely Botosoamananto ◽

Gildas Todinanahary ◽

Andriamanjato Razakandrainy ◽

Mahery Randrianarivo ◽

Lucie Penin ◽

...

Keyword(s):

Community Structure ◽

Spatial Heterogeneity ◽

Marine Protected Areas ◽

Size Structure ◽

Coral Cover ◽

Coral Community ◽

Large Area ◽

Coral Assemblage ◽

The 1960S ◽

Positive Results

The Great Reef of Toliara, on the southwestern coast of Madagascar, has been documented as harbouring flourishing reef communities in the 1960s, but has since been affected by various threats, causing a coral decline last reported in 2008. In 2017, we examined the spatial heterogeneity in coral community structure in the region of Toliara. Coral assemblages were characterized by a marked spatial variability, with significant variation for most of the descriptors among the three major habitats and also among stations within habitats. We recorded high coral cover, with values >40% at six of the 10 stations, which was associated with high abundance of coral colonies. We also documented the return to an Acropora-dominated coral assemblage. While these positive results suggest a recent return to healthier coral assemblages, they must be tempered, as the diversity that we recorded was lower than in the 1960s. Moreover, we found a high cover of algae at several stations, suggesting that the ecosystem is likely close to the tipping point toward a phase shift. Finally, the population size-structure of major coral taxa was positively skewed, with few large colonies to ensure the replenishment of local populations. The marked spatial variation suggests that marine protected areas should integrate a sufficiently large area to capture the scale of this spatial heterogeneity.

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Wave exposure shapes reef community composition and recovery trajectories at a remote coral atoll

Coral Reefs ◽

10.1007/s00338-021-02184-w ◽

2021 ◽

Author(s):

Ines D. Lange ◽

Cassandra E. Benkwitt ◽

Jamie M. McDevitt-Irwin ◽

Kristina L. Tietjen ◽

Brett Taylor ◽

...

Keyword(s):

Community Composition ◽

Benthic Community ◽

Coral Cover ◽

Principal Component ◽

Wave Exposure ◽

Ecological Change ◽

Live Coral ◽

Bleaching Event ◽

Community Patterns ◽

Similar Survey

AbstractIn a time of unprecedented ecological change, understanding natural biophysical relationships between reef resilience and physical drivers is of increasing importance. This study evaluates how wave forcing structures coral reef benthic community composition and recovery trajectories after the major 2015/2016 bleaching event in the remote Chagos Archipelago, Indian Ocean. Benthic cover and substrate rugosity were quantified from digital imagery at 23 fore reef sites around a small coral atoll (Salomon) in 2020 and compared to data from a similar survey in 2006 and opportunistic surveys in intermediate years. Cluster analysis and principal component analysis show strong separation of community composition between exposed (modelled wave exposure > 1000 J m−3) and sheltered sites (< 1000 J m−3) in 2020. This difference is driven by relatively high cover of Porites sp., other massive corals, encrusting corals, soft corals, rubble and dead table corals at sheltered sites versus high cover of pavement and sponges at exposed sites. Total coral cover and rugosity were also higher at sheltered sites. Adding data from previous years shows benthic community shifts from distinct exposure-driven assemblages and high live coral cover in 2006 towards bare pavement, dead Acropora tables and rubble after the 2015/2016 bleaching event. The subsequent recovery trajectories at sheltered and exposed sites are surprisingly parallel and lead communities towards their respective pre-bleaching communities. These results demonstrate that in the absence of human stressors, community patterns on fore reefs are strongly controlled by wave exposure, even during and after widespread coral loss from bleaching events.

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Variation in the components of Benthic community structure in a Coastal Lagoon as a function of Spatial Scale

Marine and Freshwater Research ◽

10.1071/mf9890079 ◽

1989 ◽

Vol 40 (1) ◽

pp. 79 ◽

Cited By ~ 18

Author(s):

A Hatcher

Keyword(s):

Community Structure ◽

Community Composition ◽

Coastal Lagoon ◽

Benthic Community ◽

Spatial Scales ◽

Small Scale ◽

Benthic Community Structure ◽

Extrinsic Factors ◽

Sessile Invertebrates ◽

Community Types

The perception of community structure is strongly related to the spatial resolution of data collection. To quantify variation in community structure at several spatial scales, the benthos was examined on the limestone substratum in a nearshore coastal lagoon. Community structure was described using a form of pattern analysis called correspondence analysis. Variance at three spatial scales was measured. These scales were described as: (I) between offshore and nearshore reefs (kilometres); (2) among areas on the nearshore reef-line (< 1 km); and (3) between community types on the nearshore reef-line (tens of metres and less). Organisms were classified according to higher taxa/functional classes. Parameters which varied between reef-lines included: (i) community composition determined using multivariate ordination, (ii) cover by calcareous and filamentous algae and (iii) abundance of seagrass and juvenile kelp (Ecklonia radiata). Among the areas on the nearshore reef-line, variance in community composition was due to the distribution of animals. There was a south to north gradient of increasing cover by encrusting animals and abundance of ascidians. Within the areas on the nearshore reef-line, there were two distinct community types characterized by macrophytic plants or sessile invertebrates. The major potential controls of the variation in benthic community structure were different at each of the spatial scales examined. The strong relationships between extrinsic factors and components of the communities suggested that the major potential controls were: (a) exposure to swell at the large scale (between reef-lines), (b) availability of food at the medium scale (within areas on the nearshore reef-line) and (c) biological interactions or responses to microtopography and light climate at the small scale (between and within communities on the nearshore reef-line).

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Coral community bleaching response on a highly urbanised reef

10.7287/peerj.preprints.760v1 ◽

2014 ◽

Author(s):

James R Guest ◽

Jeffrey Low ◽

Karenne Tun ◽

Jani I Tanzil ◽

Peter A Todd ◽

...

Keyword(s):

Community Structure ◽

Thermal Stress ◽

Anthropogenic Impacts ◽

Coral Cover ◽

Regional Scale ◽

Coral Community ◽

Bleaching Response ◽

Sea Surface Temperature Anomalies ◽

Relative Cover ◽

June July

Projected increases in the magnitude and frequency of sea surface temperature anomalies present a significant threat to the persistence of tropical coral reefs, however, detailed studies of community level responses to thermal stress are needed if its effect on reef resilience are to be understood. While many studies report on broad, regional scale responses to thermal stress (e.g., proportion of corals bleached), far fewer examine variation in susceptibility among taxa and change in coral community structure, before, during and after bleaching on individual reefs. Furthermore, relatively few studies of bleaching response come from highly urbanised reefs that experience chronic disturbances such as elevated sedimentation and turbidity. Here we report in detail on the bleaching response of corals at a highly urbanised reef site south of mainland Singapore during (June, July) and immediately after (October) a major thermal coral bleaching event in 2010. To estimate the capacity for resistance and resilience to thermal stress, we report on a) the overall bleaching severity during and after the event, b) differences in bleaching susceptibility among taxa during the event and c) the response of the reef in terms of taxonomic community structure before (2009) and after (2012) bleaching. Despite severe bleaching in 2010 (66% of colonies bleached), post-bleaching recovery appeared to be relatively rapid and coral taxa that are usually highly susceptible (e.g., Acropora and Pocillopora) were relatively unaffected, i.e., either they did not bleach or they bleached and recovered. Although there was no significant change in coral taxonomic community structure among years, taxa that bleached most severely tended to have the greatest reductions in relative cover. Several factors may have contributed to the overall high resistance of this site to bleaching including turbidity, symbiont affiliation and heterotrophy. A parsimonious explanation for the reversed pattern of bleaching susceptibility among taxa is that these coral populations have adapted and/or acclimatised to thermal stress. Despite ongoing chronic anthropogenic impacts, we suggest that this site has potential for rapid recovery of coral cover due to the dominant coral taxa and growth forms being capable of rapid regrowth from remnant colonies.

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Cross-Shelf Variation in Coral Community Response to Disturbance on the Great Barrier Reef

Diversity ◽

10.3390/d11030038 ◽

2019 ◽

Vol 11 (3) ◽

pp. 38 ◽

Cited By ~ 7

Author(s):

Camille Mellin ◽

Angus Thompson ◽

Michelle J. Jonker ◽

Michael J. Emslie

Keyword(s):

Great Barrier Reef ◽

Community Composition ◽

Community Dynamics ◽

Coral Cover ◽

Light Attenuation ◽

Coral Community ◽

Community Response ◽

Outer Shelf ◽

Barrier Reef ◽

Chronic Stressors

Changes in coral reef health and status are commonly reported using hard coral cover, however such changes may also lead to substantial shifts in coral community composition. Here we assess the extent to which coral communities departed from their pre-disturbance composition following disturbance (disassembly), and reassembled during recovery (reassembly) along an environmental gradient across the continental shelf on Australia’s Great Barrier Reef. We show that for similar differences in coral cover, both disassembly and reassembly were greater on inshore reefs than mid- or outer-shelf reefs. This pattern was mostly explained by spatial variation in the pre-disturbance community composition, of which 28% was associated with chronic stressors related to water quality (e.g., light attenuation, concentrations of suspended sediments and chlorophyll). Tropical cyclones exacerbated the magnitude of community disassembly, but did not vary significantly among shelf positions. On the outer shelf, the main indicator taxa (tabulate Acropora) were mostly responsible for community dissimilarity, whereas contribution to dissimilarity was distributed across many taxa on the inner shelf. Our results highlight that community dynamics are not well captured by aggregated indices such as coral cover alone, and that the response of ecological communities to disturbance depends on their composition and exposure to chronic stressors.

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