Mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event

This work analyzes the mortality, recovery, and shifts in the composition of scleractinian corals from Puerto Rico one decade after the 2005 regional coral bleaching event. Temporal and spatial patterns of coral community structure were examined using a stratified, non-random sampling approach based on five permanent transects per reef at 16 reef stations. A negative correlation between percent coral cover loss and light attenuation coefficient (Kd490) was observed, suggesting that light attenuation, as influenced by water turbidity and depth, played a major role in coral protection during the bleaching event (“sunblock effect”). Responses of coral assemblages varied after the bleaching event, including shifts of cover from massive corals (Orbicellaspp.) to opportunistic (Porites astreoides) and branching corals (Madracis auretenra,P. porites) and/or turf algae; partial recovery of reef substrate cover byO. annulariscomplex; and no measurable changes in coral assemblages before and after the event.

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The mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event

10.7287/peerj.preprints.2898v1 ◽

2017 ◽

Author(s):

Jorge R García-Sais ◽

Stacey M Williams ◽

Ali Amirrezvani

Keyword(s):

Puerto Rico ◽

Coral Cover ◽

Light Attenuation ◽

Coral Community ◽

Scleractinian Corals ◽

Partial Recovery ◽

Bleaching Event ◽

Before And After ◽

Coral Recovery ◽

And Shifts

This work analyzes the mortality, recovery, and shifts in the composition of scleractinian corals in Puerto Rico one decade after the 2005 regional coral bleaching event. Temporal and spatial patterns of coral community structure were examined using a stratified, non-random sampling approach based on five permanent transects per reef at 16 reef stations. A negative correlation between percent coral cover loss and light attenuation coefficient (Kd490) was observed, suggesting that water turbidity played a major role in coral protection during the bleaching event (“sunblock effect”). Loss of coral cover after the bleaching event was lower at nearshore reefs, and with increasing depth at oceanic and shelf-edge reefs. By 2015, coral recovery was observed at all reefs surveyed, but coastal reefs exhibited a higher rate of recovery. The responses of coral assemblages varied after the bleaching event, including shifts in cover from massive corals (Orbicella spp.) to turf algae and/or by opportunistic (Porites astreoides) and branching corals (Madracis auretenra, P. porites); partial recovery by O. annularis complex; and no measurable change in coral assemblages before and after the event.

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The mortality, recovery, and community shifts of scleractinian corals in Puerto Rico one decade after the 2005 regional bleaching event

10.7287/peerj.preprints.2898 ◽

2017 ◽

Author(s):

Jorge R García-Sais ◽

Stacey M Williams ◽

Ali Amirrezvani

Keyword(s):

Puerto Rico ◽

Coral Cover ◽

Light Attenuation ◽

Coral Community ◽

Scleractinian Corals ◽

Partial Recovery ◽

Bleaching Event ◽

Before And After ◽

Coral Recovery ◽

And Shifts

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Prey selection of corallivorous muricids at Koh Tao (Gulf of Thailand) four years after a major coral bleaching event

Contributions to Zoology ◽

10.1163/18759866-08503003 ◽

2016 ◽

Vol 85 (3) ◽

pp. 291-309 ◽

Cited By ~ 14

Author(s):

Michelangelo S. Moerland ◽

Chad M. Scott ◽

Bert W. Hoeksema

Keyword(s):

Coral Bleaching ◽

Resource Selection ◽

Prey Availability ◽

Prey Selection ◽

Coral Cover ◽

Coral Community ◽

Live Coral ◽

Bleaching Event ◽

Major Outbreak ◽

Depth Ranges

Corallivorous Drupella (Muricidae) snails at Koh Tao are reported to have extended their range of prey species following a major coral bleaching event in 2010. Populations of their preferred Acropora prey had locally diminished in both size and abundance, and the snails had introduced free-living mushroom corals in their diet. Although the coral community largely recovered, the Drupella population grew and reached outbreak proportions. For this study, corallivorous muricids at Koh Tao were studied more intensively to examine their identities, distribution and prey choice four years after the bleaching event. Drupella rugosa was identified as the major outbreak species and occurred at densities > 3 m-2 in depth ranges of 2-5 and 5-8 m. The density of D. rugosa was related to the live coral cover, Acropora colony density, and depth. Resource selection ratios revealed that species of Acropora, Psammocora and Pavona corals were attacked more frequently than would be expected based on their availability. Strikingly, fungiid corals were now avoided as prey in the recovered coral community, despite them being part of the preferred diet directly after the bleaching. Although D. rugosa showed a clear prey preference, it appears to be plastic by changing with prey availability. The muricids Drupella margariticola and Morula spinosa occurred in much lower densities and were less often associated with corals. Snails of the opportunistic corallivore D. margariticola usually co-occurred in D. rugosa aggregations, although they also formed feeding aggregations by themselves. Whether M. spinosa generally associates with corals as a corallivore or a scavenger has yet to be determined. Molecular analyses did not reveal cryptic speciation among snails sampled from different coral hosts and also no geographic variation. The present study also showed that corallivory is more common among D. margariticola and M. spinosa than previously known.

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Shallow-water hard corals (Hexacorallia: Scleractinia) from Bangka Belitung Islands Waters, Indonesia

Aceh Journal of Animal Science ◽

10.13170/ajas.4.2.14571 ◽

2019 ◽

Vol 4 (2) ◽

pp. 89-98

Author(s):

Singgih A. Putra ◽

Helmy Akbar ◽

Indra A. Syari

Keyword(s):

Coral Reef ◽

Coral Cover ◽

Anthropogenic Activities ◽

Coral Community ◽

Scleractinian Corals ◽

Seagrass Beds ◽

Mangrove Forests ◽

Dead Coral ◽

The Status ◽

Line Intercept

Bangka Belitung Islands (Sumatra, Indonesia) has various coastal resources, e.g., coral reefs, seagrass beds, mangrove forests. However, the coral community has been threatened by anthropogenic activities, i.e., tin mining and illegal tin mining. Threatened species assessment is important for mitigation of coral losses and management. The ojective of the present study was to examine the status of Scleractinian corals in Bangka Belitung Islands, Indonesia. A line intercept transect was performed for the coral reef survey. Live and dead coral cover were recorded in the three locations. Corals species were identified following taxonomic revisions. The results showed that there were 142 species of Scleractinian corals recorded from Bangka Belitung Islands. Of these, 22 species are the new report from the areas of the the eastern part of Belitung Island. Family of Merulinidae, Acroporidae, and Poritidae were predominant group in this region. It is concluded that the condition of the coral reef ecosystem in the Belitung Islands is relatively good, but fair in Gaspar Strait and Bangka Island. Keywords: Coral cover, coral diversity, hard coral, Scleractinia

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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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Nitrogen enrichment in macroalgae following mass coral mortality

Coral Reefs ◽

10.1007/s00338-021-02079-w ◽

2021 ◽

Author(s):

Eleanor J. Vaughan ◽

Shaun K. Wilson ◽

Samantha J. Howlett ◽

Valeriano Parravicini ◽

Gareth J. Williams ◽

...

Keyword(s):

Coral Reefs ◽

Coral Cover ◽

Strong Association ◽

French Polynesia ◽

Mass Mortality ◽

Transplant Experiment ◽

Bleaching Event ◽

Coral Mortality ◽

Absolute Increase ◽

Inorganic Matter

AbstractScleractinian corals are engineers on coral reefs that provide both structural complexity as habitat and sustenance for other reef-associated organisms via the release of organic and inorganic matter. However, coral reefs are facing multiple pressures from climate change and other stressors, which can result in mass coral bleaching and mortality events. Mass mortality of corals results in enhanced release of organic matter, which can cause significant alterations to reef biochemical and recycling processes. There is little known about how long these nutrients are retained within the system, for instance, within the tissues of other benthic organisms. We investigated changes in nitrogen isotopic signatures (δ15N) of macroalgal tissues (a) ~ 1 year after a bleaching event in the Seychelles and (b) ~ 3 months after the peak of a bleaching event in Mo’orea, French Polynesia. In the Seychelles, there was a strong association between absolute loss in both total coral cover and branching coral cover and absolute increase in macroalgal δ15N between 2014 and 2017 (adjusted r2 = 0.79, p = 0.004 and adjusted r2 = 0.86, p = 0.002, respectively). In Mo’orea, a short-term transplant experiment found a significant increase in δ15N in Sargassum mangarevense after specimens were deployed on a reef with high coral mortality for ~ 3 weeks (p < 0.05). We suggest that coral-derived nutrients can be retained within reef nutrient cycles, and that this can affect other reef-associated organisms over both short- and long-term periods, especially opportunistic species such as macroalgae. These species could therefore proliferate on reefs that have experienced mass mortality events, because they have been provided with both space and nutrient subsidies by the death and decay of corals.

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Assessing population collapse of Drupella spp. (Mollusca: Gastropoda) 2 years after a coral bleaching event in the Republic of Maldives

Hydrobiologia ◽

10.1007/s10750-021-04546-5 ◽

2021 ◽

Author(s):

L. Saponari ◽

I. Dehnert ◽

P. Galli ◽

S. Montano

Keyword(s):

Coral Bleaching ◽

Prey Availability ◽

Coral Cover ◽

Environmental Data ◽

High Plasticity ◽

Bleaching Event ◽

Coral Recovery ◽

The Republic ◽

The Impact ◽

Line Intercept

AbstractCorallivory causes considerable damage to coral reefs and can exacerbate other disturbances. Among coral predators, Drupella spp. are considered as delayer of coral recovery in the Republic of Maldives, although little information is available on their ecology. Thus, we aimed to assess their population structure, feeding behaviour and spatial distribution around 2 years after a coral bleaching event in 2016. Biological and environmental data were collected using belt and line intercept transects in six shallow reefs in Maldives. The snails occurred in aggregations with a maximum of 62 individuals and exhibited a preference for branching corals. Yet, the gastropods showed a high plasticity in adapting feeding preferences to prey availability. Drupella spp. were homogenously distributed in the study area with an average of 9.04 ± 19.72 ind/200 m2. However, their occurrence was significantly different at the reef scale with the highest densities found in locations with higher coral cover. The impact of Drupella spp. appeared to be minimal with the population suffering from the loss of coral cover. We suggest that monitoring programs collect temporal- and spatial-scale data on non-outbreaking populations or non-aggregating populations to understand the dynamics of predation related to the co-occurrence of anthropogenic and natural impacts.

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Coverage Increases of Porites astreoides in Grenada Determined by Shifts in Size-Frequency Distribution

Diversity ◽

10.3390/d13070288 ◽

2021 ◽

Vol 13 (7) ◽

pp. 288

Author(s):

Ryan G. Eagleson ◽

John S. Lumsden ◽

Lorenzo Álvarez-Filip ◽

Christophe M. Herbinger ◽

Ryan A. Horricks

Keyword(s):

Coral Community ◽

Scleractinian Corals ◽

Area Measurement ◽

Coralline Algae ◽

Measurement Tool ◽

Size Frequency Distribution ◽

Point Count ◽

Porites Astreoides ◽

The Mean ◽

The Caribbean

Despite coral community collapse, the mustard hill coral (Porites astreoides) is a species currently experiencing success throughout the Caribbean. The inshore reefs of Grenada were selected to study the influence of benthic factors on the abundance, size, and coverage of P. astreoides colonies. Surveys of reef communities along established 30 m transects were conducted at eight sites in 2014 and 2017 using a 0.5 m² quadrat. Coral Point Count was used to annotate the images, estimating the coverage of scleractinian corals, sponges, algae, and benthic substrates. Coverage, size, and abundance of P. astreoides colonies were quantified using the area measurement tool in ImageJ standardized against the quadrats. There were significant differences in benthic community assemblages between islands, selected sites, and between years. From 2014 to 2017 there was a significant decrease in the mean abundance of P. astreoides colonies and significant increases in mean colony size and coverage. The presence of P. astreoides colonies was significantly correlated with: rubble (−), sand (−); pavement (+); macroalgae (−); coralline algae (+); sponges (varying response); gorgonians (−); massive corals (+); and branching corals (−). P. astreoides follows similar recruitment patterns as other scleractinian corals. Observed changes in P. astreoides populations appear to indicate a recovery event following a disturbance, potentially tropical storm Chantal in 2013.

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Apparent stability of a low-density Diadema antillarum regime for Puerto Rican coral reefs

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy093 ◽

2018 ◽

Vol 75 (6) ◽

pp. 2193-2201 ◽

Cited By ~ 3

Author(s):

Ruber Rodríguez-Barreras ◽

Alfredo Montañez-Acuña ◽

Abimarie Otaño-Cruz ◽

Scott D Ling

Keyword(s):

Puerto Rico ◽

Sea Urchin ◽

Coral Cover ◽

Live Coral ◽

Low Density ◽

Limited Evidence ◽

Diadema Antillarum ◽

Benthic Habitats ◽

Stable Regime ◽

Apparent Stability

Abstract Caribbean reefs have suffered decline in coral cover in recent decades due to recurrent anthropogenic and natural stressors. The regional collapse of the sea urchin Diadema antillarum, combined with overfishing, has contributed to a phase-shift of coral reef communities towards fleshy macroalgal dominance. Here, we examine the population dynamics of D. antillarum at five sites in Puerto Rico from 2011 to 2016 and determine trends between the sea urchin and local benthic habitats. The sea urchin population exhibited low but stable densities (with slight, but non-significant trend of increase), yet showed variability between sites. Large urchins (>60 mm test diam.) were the most abundant across sites and through time, followed by medium urchins (41–60 mm test diam.), whereas small individuals (<40 mm) were rare, indicating recruitment-limitation. Spatial and temporal differences in benthic habitats were not related to local D. antillarum abundances. Macroalgae cover declined at all sites over the 6 years, ranging 5–86%, whereas live coral cover also decreased across all sites (ranging 4–38%). Diadema antillarum populations in Puerto Rico appear stable with limited evidence for recovery trends back to pre-mass mortality densities. Full population recovery may take longer than expected; however, evidence indicates that the contemporary low-density D. antillarum population represents a novel stable regime.

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River Streamflow, Remotely Sensed Water Quality, and Benthic Composition of Previously Undescribed Nearshore Coral Reefs in Northern Puerto Rico

Frontiers in Marine Science ◽

10.3389/fmars.2021.720712 ◽

2021 ◽

Vol 8 ◽

Author(s):

Juan L. Torres-Pérez ◽

Carlos E. Ramos-Scharrón ◽

William J. Hernández ◽

Roy A. Armstrong ◽

Maritza Barreto-Orta ◽

...

Keyword(s):

Water Quality ◽

Puerto Rico ◽

Coral Reefs ◽

Coral Species ◽

Coral Cover ◽

Remotely Sensed ◽

North Coast ◽

Acropora Palmata ◽

Chl A ◽

Benthic Composition

Land-based sediment stress represents a threat to many coral reefs in Puerto Rico primarily as a result of unrestricted land cover/land use changes and poor best management practices. The effects of such stresses have been documented along most coasts around the island. However, little attention has been paid to reefs located on the north coast, and very little is known about their composition and current state. Here, we present a study characterizing riverine inputs, water quality conditions, and benthic composition of two previously undescribed coral reefs (Tómbolo and Machuca reefs) located just eastward of the Río Grande de Manatí outlet in north-central Puerto Rico. This study utilizes a time series of remotely sensed ocean color products [diffuse vertical attenuation coefficient at 490 nm (Kd490) and chlorophyll-a concentration (Chl-a) estimated with data from the Visible Infrared Imaging Radiometer Suite (VIIRS)] to characterize water quality in this coastal region. In general, the months with relatively high mean daily river streamflow also coincide with months having the highest proportion of eastward wave direction, which can promote the eastward influence of river waters toward the two coral reefs sites. Kd490 and Chl-a showed a higher riverine influence closer to the watershed outlet. Kd490 and Chl-a monthly peaks also coincide with river streamflow highs, particularly at those pixels closer to shore. Tómbolo Reef, located farther eastward of the river outlet, shows a well-developed primary reef framework mainly composed of threatened reef-building species (Acropora palmata, Pseudodiploria) and high coral cover (19–51%). The benthos of Machuca Reef, located closer to the river outlet, is dominated by macroalgae with a significantly lower coral cover (0.2–2.7%) mainly composed of “weedy” coral species (Porites astreoides and Siderastrea radians). Cover of major benthic components correlates with distance from the river outlet, and with gradients in Kd490 and Chl-a, with higher coral cover and lower macroalgal cover farther from the river outlet. Coral cover at Tómbolo Reef is higher than what has been reported for similar sites around Puerto Rico and other Caribbean islands showing its ecological importance, and as up until now, an unrecognized potential refuge of reef-building threatened coral species.

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