The Coral Bleaching Automated Stress System (CBASS): A low‐cost, portable system for standardized empirical assessments of coral thermal limits

Limnology and Oceanography Methods, Journal Year: 2023, Volume and Issue: 21(7), P. 421 - 434

Published: May 27, 2023

Abstract Ocean warming is increasingly affecting marine ecosystems across the globe. Reef‐building corals are particularly affected by warming, with mass bleaching events increasing in frequency and leading to widespread coral mortality. Yet, some can resist or recover from better than others. Such variability thermal resilience could be critical reef persistence; however, scientific community lacks standardized diagnostic approaches rapidly comparatively assess vulnerability prior events. We present Coral Bleaching Automated Stress System (CBASS) as a low‐cost, open‐source, field‐portable experimental system for rapid empirical assessment of thresholds using temperature stress profiles diagnostics. The CBASS consists four eight flow‐through aquaria independent water masses, lighting, individual automated controls capable delivering custom modulating profiles. used conduct daily exposures that typically include 3‐h ramps multiple target temperatures, hold period at 1‐h ramp back down ambient temperature, followed an overnight recovery period. This mimics shallow observed reefs prompts acute heat response serve tool identify putative thermotolerant in‐depth assessments adaptation mechanisms, targeted conservation, possible use restoration efforts. deployable within hours assay up 40 fragments/aquaria/day, enabling high‐throughput, determination genotypes, populations, species, sites framework.

Language: Английский

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Assessing acute thermal assays as a rapid screening tool for coral restoration

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Jan. 22, 2024

Abstract Escalating environmental threats to coral reefs coincides with global advancements in restoration programs. To improve long-term efficacy, practitioners must consider incorporating genotypes resilient ocean warming and disease while maintaining genetic diversity. Identifying such typically occurs under exposures that mimic natural stressors, but these experiments can be time-consuming, costly, introduce tank effects, hindering scalability for hundreds of nursery used outplanting. Here, we evaluated the efficacy acute Coral Bleaching Automated Stress System (CBASS) against on bleaching response Acropora cervicornis , dominant species Florida’s Reef. Comparing metrics, F v / m chlorophyll, host protein, observed similar responses between heat CBASS treatment 34.3 °C, which was also calculated threshold. This suggests potential as a rapid screening tool, 90% exhibiting tolerances. However, variations phenotypes arose from measurement timing experiment accumulation, cautioning generalizations solely based metrics like . These findings identify need better refine tools necessary quickly effectively screen determine their relative tolerance interventions.

Language: Английский

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The effects of marine heatwaves on acute heat tolerance in corals

Global Change Biology, Journal Year: 2022, Volume and Issue: 29(2), P. 404 - 416

Published: Oct. 26, 2022

Scleractinian coral populations are increasingly exposed to conditions above their upper thermal limits due marine heatwaves, contributing global declines of reef ecosystem health. However, historic mass bleaching events indicate there is considerable inter- and intra-specific variation in tolerance whereby species, individual colonies show differential susceptibility exposure elevated temperatures. Despite this, we lack a clear understanding how heat varies across large contemporary historical environmental gradients, or the selective pressures that underpin this variation. Here conducted standardised acute stress experiments identify among species isolated reefs spanning gradient Coral Sea Marine Park. We quantified photochemical yield (Fv /Fm ) samples three Acropora cf humilis, Pocillopora meandrina, verrucosa, following four temperature treatments (local ambient temperatures, + 3°C, +6°C 9°C local maximum monthly mean). at which Fv decreased by 50% (termed ED50) used derived values directly compare species. The ED50 for was 0.4-0.7°C lower than either with 0.3°C difference between two also recorded 0.9°C 1.9°C phenotypic within indicating spatial heterogeneity broad gradients. Acute had strong positive relationship mild heatwave over past 35 years (since 1986) but negatively related recent severe heatwaves (2016-2020). Phenotypic associated history environments provides supportive evidence selecting tolerant individuals populations; however, adaptive potential may be compromised heatwaves.

Language: Английский

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Management approaches to conserve Australia’s marine ecosystem under climate change

Science, Journal Year: 2023, Volume and Issue: 381(6658), P. 631 - 636

Published: Aug. 10, 2023

Australia's coastal marine ecosystems have a deep cultural significance to Indigenous Australians, include multiple World Heritage sites, and support the nation's rapidly growing blue economy. Yet, increasing local pressures global climate change are expected undermine biological, social, cultural, economic value of these within human generation. Mitigating causes is most urgent action secure their future; however, conventional new management actions will play roles in preserving ecosystem function until that achieved. This includes strategies codeveloped with Australians guided by traditional ecological knowledge modeling decision framework. We provide examples developments at one iconic ecosystems, Great Barrier Reef, where recent, large block funding supports research, governance, engagement accelerate development tools for under change.

Language: Английский

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Heat tolerance varies considerably within a reef-building coral species on the Great Barrier Reef

Communications Earth & Environment, Journal Year: 2024, Volume and Issue: 5(1)

Published: Sept. 23, 2024

Language: Английский

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Environmental, host, and symbiont drivers of heat tolerance in a species complex of reef-building corals

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 1, 2024

Abstract Reef-building coral populations are under unprecedented threat from climate warming. Yet, variation in heat tolerance exists whereby some colonies can cope with higher sea temperatures than others and thus may hold unique value for conservation restoration. Here, we quantify of an ecologically important tabular species complex across the Great Barrier Reef (GBR) while also measuring genomic host symbiont partners. Coral bleaching photochemical traits were measured 569 within Acropora hyacinthus 17 reefs following exposure to standardized acute stress assays. We detected substantial tolerance, where individual colony thermal thresholds differed by up 7.3°C 5.7°C among reefs, respectively. Sea surface temperature climatology was strongest predictor warmer northern inshore typically exhibited highest thresholds, cooler southern able tolerate greater increases relative their local summer temperatures. Heat positively associated weeks preceding measurements. Assignment clusters revealed four putative A. that did not vary responses experimental stress. Symbiodiniaceae communities comprised primarily Cladocopium ITS2 variants spatially but had minimal effect on tolerance. Between 36 - 80% explained environmental, host, predictors, leaving 20 64% be additional underlying drivers such as functional here. These results used inform restoration actions, including targeting tolerant individuals selective breeding, will provide a foundation evaluating basis

Language: Английский

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Short-term stress testing predicts subsequent natural bleaching variation

Coral Reefs, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 6, 2025

Reef degradation induced by climate change is motivating interest in active management strategies to retain living coral cover including restoration. Understanding the level and range of heat tolerance available populations critical determining their viability may be important choosing corals propagate for restoration projects. There a need assess experimentally relate experimental performance real-world bleaching conditions outcomes. We sampled model population key reef-building (Montipora capitata) Kāneʻohe Bay, Oʻahu, Hawaiʻi subjected fragments an artificial stress profile. subsequently revisited assessed source colonies at height natural event. Measurements photosystem efficiency taken on samples during were predictive subsequent field responses colonies. By additive modeling along with previous measures symbiont community site characteristics, we improved predictions later Survival measured several months after experiencing had strong positive value outcomes but also produced many false negatives. These results support notion that complex trait detectable partitioning its underlying sources. This work reinforces utility heat-based experimentation both understanding biological underpinnings gleaning information about individual has direct applicability conservation forecasting activities.

Language: Английский

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Laboratory experiments revealed different bleaching susceptibilities to heat stress in eight species of subtropical urban corals

Marine Environmental Research, Journal Year: 2025, Volume and Issue: 208, P. 107132 - 107132

Published: April 6, 2025

Understanding species' susceptibility to environmental stressors is crucial for conservation planning, but such data are unavailable many subtropical corals. We therefore conducted 1-month laboratory experiments determine the heat stress of eight species from areas by exposing them 32 °C (treatment) or 25 (control). Four (Dipsastraea rotumana, Echinophyllia aspera, Pavona decussata, and Platygyra carnosa) survived whole experiment, although bleaching occurred after one two weeks exposure. The exposure caused total mortality in other four species: on day 2 Acropora solitaryensis, 7 digitifera, 9 pruinosa, 17 Montipora peltiformis. These results suggest that repeated heatwaves may cause changes coral communities causing disproportionally high heat-sensitive species. Coral tested this study, collected reefs previously thought be refuges under global warming, demonstrated greater than their tropical counterparts. This raises concerns about persistence as sea surface temperatures continue rise.

Language: Английский

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Thermal tolerance traits of individual corals are widely distributed across the Great Barrier Reef

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 29, 2024

Abstract Adaptation of reef-building corals to global warming depends upon standing heritable variation in tolerance traits which selection can act. Yet limited knowledge exists on heat among conspecific individuals separated by meters hundreds kilometers. Here, we performed standardized acute stress assays quantify the thermal 768 colonies Acropora spathulata from 14 reefs spanning 1060 km (9.5° latitude) Great Barrier Reef. Thermal thresholds for photochemical efficiency and chlorophyll retention varied considerably individual both (∼6 °C) within (∼3 °C). Although rankings between traits, most tolerant (i.e. top 25% each trait) were found at virtually all reefs, indicating widespread phenotypic variation. Reef-scale environmental predictors explained 12–62% trait Corals exposed high averages recent exhibited greatest performance, likely reflecting local adaptation pre-acclimatization, lowest suggesting pre- sensitization. Importantly, relative summer temperatures was southern suggestive higher adaptive potential. These results be used identify naturally coral populations conservation restoration applications.

Language: Английский

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Thermal tolerance traits of individual corals are widely distributed across the Great Barrier Reef

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2030)

Published: Sept. 1, 2024

Adaptation of reef-building corals to global warming depends upon standing heritable variation in tolerance traits which selection can act. Yet limited knowledge exists on heat-tolerance among conspecific individuals separated by metres hundreds kilometres. Here, we performed standardized acute heat-stress assays quantify the thermal 709 colonies

Language: Английский

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