Find research datasets worth reusing

opencc-by-4.0Jan 2021View details →

Mortality, growth and reproduction in five species of scleractinian corals following bleaching on the Great Barrier Reef in 1998

Study sites: These data were collected on the fringing reefs on the west side of Orpheus Island at Little Pioneer Bay (S18.594°, E146.485°), and the south-eastern side of Pelorus Island (S18.560°, E146.500°). Both islands are continental islands of the Palm Islands group in the Central Section of the Great Barrier Reef (GBR) Marine Park. These sites were amongst the worst affected by bleaching on the GBR following a sharp rise in sea surface temperature in the early months of 1998 (Berkelmans and Oliver 1999) Species response to and recovery from high Sea Surface Temperature (SST): On 24 March 1998, all living colonies of Acropora millepora (n = 37) and A. hyacinthus (n = 28) in a 20 m × 40 m area between 3-4 m deep on the fringing reef of south-east of Pelorus Island were tagged to examine the patterns of response to, and recovery from, high SST. Similarly, all colonies of Seriatopora hystrix at 10 m depth within a 5 by 40 m area at this site were tagged (n=27). Platygyra daedalea (n = 28) and Porites lobata (n = 14) at 3-4 m depth in an area of approximately 50 m × 10 m were tagged at Little Pioneer Bay on Orpheus Island. The extent of colony bleaching was classified into 6 categories following Marshall and Baird (2000): 1 = no bleaching; 2 = uniformly pale; 3 = 1-50; 4 = 51-99; 5 = 100% bleached, and 6 = dead. Colonies that were fluorescent were categorized as 100% bleached. The extent of colony bleaching was estimated on six occasions following the initial report of bleaching at these sites on 10 February 1998 (Hoegh-Guldberg 1999). Colony size: The size of P. daedalea colonies was determined from the maximum colony diameter of colonies at the initial census, which ranged from 10 to 40 cm. The projected area of the two species of Acropora was estimated from digitized photos of the colonies. The volume of Seriatopora hystrix was estimated by multiplying maximum diameter width x the perpendicular of maximum colony diameter x maximum colony height. All lengths were measured to the nearest cm with a tape measure. Partial mortality: Partial mortality was estimated as the proportion of the pre-bleaching tissue lost within each colony, estimated to the nearest 5%. Values ranged from zero (escape from injury) through various amounts of injury (partial mortality) to 100% (whole-colony mortality). Alternatively, in Seriatopora hystrix a categorical scale identical to the bleaching categories described above was used. References Berkelmans R, Oliver JK (1999) Large-scale bleaching of corals on the Great Barrier Reef. Coral Reefs 18:55-60 Hoegh-Guldberg O (1999) Climate change, coral bleaching and the future of the world's coral reefs. Mar Freshwat Res 50:839-866 Marshall PA, Baird AH (2000) Bleaching of corals on the Great Barrier Reef: differential susceptibilities among taxa. Coral Reefs 19:155-163

opencc-by-4.0May 2021View details →

Fig. 1 in Histopatological effects of bleaching and disease on the coral Siderastrea stellata from coastal reefs of Brazil

Fig. 1. Areas where corals were sampled, Ponta do SeiXas, state of ParaÍba, Brazil.

opencc-by-4.0Sep 2024View details →

Data from 'Hot spots of bleaching in massive Porites coral colonies'

Data from 'Hot spots of bleaching in massive Porites coral colonies' published in Marine Environmental Research.

openother-openAug 2021View details →

Coral cover and coral bleaching in the Gulf of Chiriqui

No description provided.

opencc-zeroOct 2021View details →

Response diversity in corals: hidden differences in bleaching mortality among cryptic Pocillopora species

Variation among functionally similar species in their response to environmental stress buffers ecosystems from changing states. Functionally similar species may often be cryptic species representing evolutionarily distinct genetic lineages that are morphologically indistinguishable. However, the extent to which cryptic species differ in their response to stress, and could therefore provide a source of response diversity, remains unclear because they are often not identified or are assumed to be ecologically equivalent. Here, we uncover differences in the bleaching response between sympatric cryptic species of the common Indo-Pacific coral, Pocillopora. In April 2019, prolonged ocean heating occurred at Moorea, French Polynesia. 72% of pocilloporid colonies bleached after 22 days of severe heating (>8°C-days) at 10 m depth on the north shore fore reef. Colony mortality ranged from 11% to 42% around the island four months after heating subsided. The majority (86%) of pocilloporids that died from bleaching belonged to a single haplotype, despite twelve haplotypes, representing at least five species, being sampled. Mitochondrial (open reading frame) sequence variation was greater between the haplotypes that experienced mortality versus haplotypes that all survived than it was between nominal species that all survived. Colonies >30 cm in diameter were identified as the haplotype experiencing the most mortality, and in 1125 colonies that were not genetically identified, bleaching and mortality increased with colony size. Mortality did not increase with colony size within the haplotype suffering the highest mortality, suggesting that size-dependent bleaching and mortality at the genus level was caused instead by differences among cryptic species. The relative abundance of haplotypes shifted between February and August, driven by declines in the same common haplotype for which mortality was estimated directly, at sites where heat accumulation was greatest, and where larger colony sizes occurred. The identification of morphologically indistinguishable species that differ in their response to thermal stress, but share a similar ecological function in terms of maintaining a coral-dominated state, has important consequences for uncovering response diversity that drives resilience, especially in systems with low or declining functional diversity.

opencc-zeroOct 2022View details →

Coral bleaching due to cold stress on a central Red Sea reef flat

Ocean warming is leading to more frequent coral bleaching events. However, cold stress can also induce bleaching in corals. Here, we report observations of a boreal winter bleaching event in Jan 2020 in the central Red Sea, mainly within a population of the branching coral Stylophora pistillata on an offshore reef flat. Sea surface temperatures rarely fall below 24°C in this region, but data loggers deployed on several nearby reef flats recorded overnight seawater temperatures as low as 18°C just three days before the observations. The low temperatures coincided with an extremely low tide and cool air temperatures, likely resulting in the aerial exposure of the corals during the nighttime low tide event. The risk of aerial exposure is rare in winter months, as the Red Sea exhibits seasonal fluctuations in sea level with winter values typically 0.3-0.4m higher than in summer. These observations are notable for a region typically characterized as a high-temperature sea, and highlight the need for long-term monitoring programs as this rare event may have gone unnoticed.

opencc-by-4.0Sep 2023View details →

Raw data and R Script: Bleaching coral event due to cold waters in the Gulf of California: effect on Pocillopora cryptofauna

R script code and raw data to reproduce the analyses made in the study "Bleaching coral event due to cold waters in the Gulf of California: effect on Pocillopora cryptofauna" published in Coral Reefs (10.1007/s00338-023-02422-3).

opencc-zeroOct 2023View details →

Algal symbiont diversity in Acropora muricata from the extreme reef of Bouraké associated with resistance to coral bleaching

Widespread coral bleaching has generally been linked to high water temperatures at larger geographic scale. However, teh bleaching response can be highly variable aming individuals of the same species, between different species, and across localities; what causes this variability remais unresolved. Here, we tracked bleached and non-bleached colonies of Acropora muricata to see if they recovered or died following a stress event inside the semi-enclosed lagoon of Bouraké (New Caledonia), where corals are long-term acclimatized to extreme conditions of temperature, pH and dissolved oxygen, and at a nearby control reef. We describe Symbiodiniaceae community changes, metabolic responses, and energetical reserves (12 physiological traits evaluated) during La Niña warm and rainy summer in 2021. Widespread coral bleaching (score 1 and 2 on coral colour health chart) was observed only in Bouraké, likely due to the combination of the high temperatures (up to 32 oC) and heavy rain. All colonies (i.e., Bouraké and reference site) had Cladocopium as their main genera. Unbleached colonies in Bouraké had a specific ITS2-type profile (proxies for Symbiodiniaceae genotypes), while the bleached colonies in Bouraké had the same ITS2-type profile of control colonies during the stress event. After four months, teh few bleached colonies thata survived acquired the same ITS2 type profiles of the unbleached resistant colonies. In terms of physiological performances, all bleached corals showed metabolic depression (e.g., Pgross and Rdark). In contrast, unbleahed colonies in Bouraké maintained higher metabolic rates and energetic reserves compared to control corals. Our study suggests that Acropora muricata enhanced their resistance to bleaching thanks to specific Symbiodiniaceae, while energetic reserves may increase their resilience after stress.

publicOct 2022View details →

Coral bleaching due to cold stress on a central Red Sea reef flat

Open the record for dataset details and reuse information.

publicOct 2023View details →

Algal symbiont diversity in Acropora muricata from the extreme reef of Bouraké associated with resistance to coral bleaching

Open the record for dataset details and reuse information.

publicSep 2017View details →

Data from: The genomics of recovery from coral bleaching

Open the record for dataset details and reuse information.

publicOct 2021View details →

Response diversity in corals: hidden differences in bleaching mortality among cryptic Pocillopora species

Open the record for dataset details and reuse information.

opencc-zeroAug 2020View details →

The legacy of stress: coral bleaching impacts reproduction years later

1. The extent to which populations persist under environmental stress depends on the reproductive output of individuals that survive the stress. In coral systems, corals bleach in response to stress from elevated water temperature. However, little is known of the extent to which thermal stress impairs the reproductive capacity of the survivors over the following years, limiting the capacity to predict how populations will persist in the Anthropocene. 2. Using histology to quantify the abundance and size of oocytes and spermaries per polyp, we tested how bleaching impairs the reproductive response of the coral Pocillopora meandrina over two reproductive seasons following the 2015 mass bleaching event in the Hawaiian Islands. 3. We found that smaller colonies not only had a greater probability of bleaching but also suffered greater reproductive impacts over a longer time. In contrast, larger colonies generated comparable reproductive output regardless of bleaching severity, although bleached colonies generated smaller oocytes the year after bleaching. 4. These results show that reproductive impacts of bleaching are more complex and size-specific than commonly assumed. Therefore, estimates of bleaching mortality may underestimate the true impact of thermal stress on populations, especially as populations lose larger individuals from repeated and co-occurring stressors.

opencc-zeroAug 2020View details →

Cryptic lineages respond differently to coral bleaching

Coral cover is decreasing worldwide largely as a result of a rise in seawater temperatures that triggers coral bleaching and induces coral mortality. How coral reefs will respond to climate change will be a function of genetic variation and how it is partitioned within and among species. A critical initial step is to accurately delineate species and quantify their physiological potential to cope with heat stress. Cryptic species are morphologically similar but genetically distinct and may respond physiologically different to climate change. A dominant Caribbean reef builder severely affected by climate change is the mountainous star coral, Orbicella faveolata. Recently, Dziedzic et al. (2019) reported quantitative genetic variation in the physiological response to thermal stress in a single population of this species, suggesting that variation within populations will allow these corals to adapt to rising ocean temperatures. We reanalyzed their data and found multiple cryptic lineages rather than a single panmictic population, with one of the lineages being not heat-tolerant. While different cryptic lineages co-occur in certain locations, there is at least one lineage that occurs only in a single location. Our finding of hidden lineages within a threatened species highlights the varying extinction risks faced by these independently evolving groups, especially when the prospects of survival under warmer oceans seem favorable for some of them only.

opencc-zeroDec 2010View details →

Data from: Multiple scales of genetic connectivity in a brooding coral on isolated reefs following catastrophic bleaching

Understanding the pattern of connectivity among populations is crucial for the development of realistic and spatially explicit population models in marine systems. Here we analysed variation at eight microsatellite loci to assess the genetic structure and to infer patterns of larval dispersal for a brooding coral, Seriatopora hystrix, at an isolated system of reefs in northern Western Australia. Spatial autocorrelation analyses show that populations are locally subdivided, and that the majority of larvae recruit to within 100 m of their natal colony. Further, a combination of F- and R- statistics showed significant differentiation at larger spatial scales (2–60 km) between sites, and this pattern was clearly not associated with distance. However, Bayesian analysis demonstrated that recruitment has been supplemented by less frequent but recent input of larvae from outside the local area; 2–6% of colonies were excluded from the site at which they were sampled. Individual assignments of these migrants to the most likely populations suggest that the majority of migrants were produced at the only site that was not decimated by a recent and catastrophic coral bleaching event. Furthermore, the only site that recovered to prebleaching levels received most of these immigrants. We conclude that the genetic structure of this brooding coral reflects its highly opportunistic life history, in which prolific, philopatric recruitment is occasionally supplemented by exogenously produced larvae.

opencc-zeroDec 2015View details →

Data from: Recovery from bleaching is mediated by threshold densities of background thermo-tolerant symbiont types in a reef-building coral

Sensitive molecular analyses show that most corals host a complement of Symbiodinium genotypes that includes thermo-tolerant types in low abundance. While tolerant symbiont types are hypothesized to facilitate tolerance to temperature and recovery from bleaching, empirical data on their distribution and relative abundance in corals under ambient and stress conditions are still rare. We quantified visual bleaching and mortality of coral hosts, along with relative abundance of C- and D-type Symbiodinium cells in 82 Acropora millepora colonies from three locations on the Great Barrier Reef transplanted to a central inshore site over a 13 month period. Our analyses reveal dynamic change in symbiont associations within colonies and among populations over time. Coral bleaching and declines in C- but not D-type symbionts were observed in transplanted corals. Survival and recovery of 25% of corals from one population was associated with either initial D-dominance or an increase in D-type symbionts that could be predicted by a minimum pre-stress D : C ratio of 0.003. One-third of corals from this population became D dominated at the bleached stage despite no initial detection of this symbiont type, but failed to recover and died in mid to late summer. These results provide a predictive threshold minimum density of background D-type symbionts in A. millepora, above which survival following extreme thermal stress is increased.

zenodo32/100

Scleractinian corals at their subtropical southwestern Atlantic limit: Post-2019 mass bleaching event analysis

Open the record for dataset details and reuse information.

opencc-by-4.0Nov 2024View details →

opencc-zeroJul 2022View details →

Species-level coral bleaching data for Maldives and GBR

Response to coral bleaching for 7368 coral colonies exposed to similar levels of temperature stress at a similar depth of occurrence and similar subsequent mortality. Collected in situ following moderate thermal bleaching events in the GBR in 2002 and the Maldives in 2016. Data gives species, site, depth of occurence and bleaching response which was scored by tissue colour.