Hidden heatwaves and severe coral bleaching linked to mesoscale eddies and thermocline dynamics

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Jan. 6, 2023

Abstract The severity of marine heatwaves (MHWs) that are increasingly impacting ocean ecosystems, including vulnerable coral reefs, has primarily been assessed using remotely sensed sea-surface temperatures (SSTs), without information relevant to heating across ecosystem depths. Here, a rare combination SST, high-resolution in-situ temperatures, and sea level anomalies observed over 15 years near Moorea, French Polynesia, we document subsurface MHWs have paradoxical in comparison SST metrics associated with unexpected bleaching Variations the depth range was driven by mesoscale (10s 100s km) eddies altered levels thermocline depths decreased (2007, 2017 2019) or increased (2012, 2015, 2016) internal-wave cooling. Pronounced eddy-induced reductions internal waves during early 2019 contributed prolonged MHW unexpectedly severe bleaching, subsequent mortality offsetting almost decade recovery. Variability eddy fields, thus depths, is expected increase climate change, which, along strengthening deepening stratification, could occurrence ecosystems historically insulated from surface cooling effects waves.

Language: Английский

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Integrating cryptic diversity into coral evolution, symbiosis and conservation

Nature Ecology & Evolution, Journal Year: 2024, Volume and Issue: 8(4), P. 622 - 636

Published: Feb. 13, 2024

Language: Английский

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Early life stage bottleneck determines rates of coral recovery following severe disturbance

Ecology, Journal Year: 2025, Volume and Issue: 106(1)

Published: Jan. 1, 2025

Abstract Understanding how foundation species recover from disturbances is key for predicting the future of ecosystems in Anthropocene. Coral reefs are dynamic that can undergo rapid declines coral abundance following disturbances. why some quickly these whereas others slowly (or not at all) gives insight into drivers community resilience. From 2006 to 2010 on fore reef Moorea, French Polynesia, experienced severe reduced cover ~46% 2005 <1% 2010. Following disturbances, increased 2018. Although there was a and widespread recovery corals, 17 m depth recovered more than 10 depth. We investigated different rates between depths 2018 using combination time‐series data recruitment, density, growth, mortality addition field experiments testing effects predation. Propagule did influence recovery, as density recruits (spat <6 months old) differ depths. However, juvenile corals (≤5 cm diameter) higher m, leading densities 3.5 times Yet, were no differences growth These results point an early life stage bottleneck after settlement, resulting greater likely driver differential used test mechanisms could drive across depths, including predation, competition, availability suitable substratum. The suggested may have been influenced by intensity fish attached unfavorable In contrast, macroalgae, competitor, explain survival. Our work suggests top‐down processes substratum quality create bottlenecks disturbance.

Language: Английский

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Cophylogeny and specificity between cryptic coral species (Pocillopora spp.) at Mo′orea and their symbionts (Symbiodiniaceae)

Molecular Ecology, Journal Year: 2022, Volume and Issue: 31(20), P. 5368 - 5385

Published: Aug. 12, 2022

Abstract The congruence between phylogenies of tightly associated groups organisms (cophylogeny) reflects evolutionary links ecologically important interactions. However, despite being a classic example an obligate symbiosis, tests cophylogeny scleractinian corals and their photosynthetic algal symbionts have been hampered in the past because both algae contain genetically unresolved morphologically cryptic species. Here, we studied co‐occurring, Pocillopora species from Mo′orea, French Polynesia, that differ relative abundance across depth. We constructed new host (using complete mitochondrial genomes, genomic loci, thousands single nucleotide polymorphisms) Symbiodiniaceae ITS2 psbA ncr markers) tested for cophylogeny. analysis supported presence five on fore reef at Mo′orea mostly hosted either Cladocopium latusorum or C. pacificum. Only hosting also taxa Symbiodinium Durusdinium . In general, phylogeny mirrored phylogeny. Within species, lineages differed associations with haplotypes, except those showing evidence nuclear introgression, depth two most common found (haplotype 10), has so far only sampled warrants formal identification. linked these suggest symbiont speciation is driven by niche diversification host, but there still flexibility some cases.

Language: Английский

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Disparate genetic divergence patterns in three corals across a pan-Pacific environmental gradient highlight species-specific adaptation

npj Biodiversity, Journal Year: 2023, Volume and Issue: 2(1)

Published: July 7, 2023

Tropical coral reefs are among the most affected ecosystems by climate change and face increasing loss in coming decades. Effective conservation strategies that maximize ecosystem resilience must be informed accurate characterization of extant genetic diversity population structure together with an understanding adaptive potential keystone species. Here we analyzed samples from Tara Pacific Expedition (2016-2018) completed 18,000 km longitudinal transect Ocean sampling three widespread corals-Pocillopora meandrina, Porites lobata, Millepora cf. platyphylla-across 33 sites 11 islands. Using deep metagenomic sequencing 269 colonies conjunction morphological analyses variability data, can show despite a targeted encompasses multiple cryptic These species exhibit disparate biogeographic patterns and, importantly, distinct evolutionary identical environmental regimes. Our findings demonstrate on basin scale trajectories species-specific only part predicted environment. This highlights integrate multi-species investigations to discern genomic footprints shaped selection as well for change.

Language: Английский

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High physiological function for corals with thermally tolerant, host-adapted symbionts

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2023, Volume and Issue: 290(2003)

Published: July 19, 2023

The flexibility to associate with more than one symbiont may considerably expand a host's niche breadth. Coral animals and dinoflagellate micro-algae represent of the most functionally integrated widespread mutualisms between two eukaryotic partners. Symbiont identity greatly affects coral's ability cope extremes in temperature light. Over its broad distribution across Eastern Pacific, ecologically dominant branching coral, Pocillopora grandis , depends on dinoflagellates Durusdinium glynnii Cladocopium latusorum . Measurements skeletal growth, calcification rates, total mass increase, calyx dimensions, reproductive output response thermal stress were used assess functional performance these partner combinations. results show both host–symbiont combinations displayed similar phenotypes; however, significant differences emerged when exposed increased temperatures. Negligible physiological colonies hosting thermally tolerant D. refute prevailing view that have considerable growth tradeoffs. Well beyond pocilloporid are found Pacific warm, environmentally variable, near shore lagoonal habitats. While rising ocean temperatures threaten persistence contemporary coral reefs, lessons from indicate co-evolved likely spread geographically dominate reef ecosystems future.

Language: Английский

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Cryptic diversity begets challenges and opportunities in biodiversity research

Integrative Zoology, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 23, 2024

Abstract How many species of life are there on Earth? This is a question that we want to know but cannot yet answer. Some scholars speculate the number may reach 2.2 billion when considering cryptic diversity and each morphology‐based insect contain an average 3.1 species. With nearly two million described species, such high estimates would suggest widespread. The development molecular delimitation has led discovery large biodiversity gradually entered our field vision attracted more attention. paper introduces concept how they evolve, methods by which be discovered confirmed, provides theoretical methodological guidance for study hidden A workflow confirm provided. In addition, importance reliability multi‐evidence‐based integrated taxonomy reaffirmed as way better standardize decision‐making processes. Special focus increased funding needed ensure in hyperdiverse groups discoverable described. An future will naturally arise difficult studied, thereby, finally understand rules governing evolution maintenance biodiversity.

Language: Английский

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Symbiodiniaceae diversity varies by host and environment across thermally distinct reefs

Molecular Ecology, Journal Year: 2024, Volume and Issue: 33(9)

Published: April 7, 2024

Abstract Endosymbiotic dinoflagellates (Symbiodiniaceae) influence coral thermal tolerance at both local and regional scales. In isolation, the effects of host genetics, environment, disturbances on symbiont communities are well understood, yet their combined remain poorly resolved. Here, we investigate Symbiodiniaceae across 1300 km in Australia's Coral Sea Marine Park to disentangle these interactive effects. We identified species‐level resolution for three species ( Acropora cf humilis, Pocillopora verrucosa , meandrina ) by sequencing two genetic markers (ITS2 psbA ncr ), paired with genotype‐by‐sequencing (DArT‐seq). Our samples predominantly returned sequences from genus Cladocopium where humilis affiliated C3k, C. pacificum latusorum . Multivariate analyses revealed that symbionts were driven strongly environment disturbances. contrast, partitioned 2.5‐fold more structure than environmental structure. Among species, genetics explained four times variation P. verrucosa. The concurrent bleaching event 2020 had variable impacts communities, consistent patterns A. but not findings demonstrate how macroscale community responses gradients depend respective population Integrating host, symbiont, data will help forecast adaptive potential corals amidst a rapidly changing environment.

Language: Английский

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Geographical patterns of intraspecific genetic diversity reflect the adaptive potential of the coral Pocillopora damicornis species complex

PLoS ONE, Journal Year: 2025, Volume and Issue: 20(1), P. e0316380 - e0316380

Published: Jan. 22, 2025

Marine heatwaves are increasing in intensity and frequency however, responses survival of reef corals vary geographically. Geographical differences thermal tolerance may be part a consequence intraspecific diversity, where high-diversity localities more likely to support heat-tolerant alleles that promote through stress. Here, we assessed geographical patterns genetic diversity the ubiquitous coral Pocillopora damicornis species complex using 428 sequences Internal Transcribed Spacer 2 (ITS2) region across 44 sites Pacific Indian Oceans. We focused on detecting hotspots, wherein some individuals possess gene variants tolerate marine heatwaves. A deep-learning, multi-layer neural-network model showed location played major role with mean sea-surface temperature oceanic regions being most influential predictor variables differentiating diversity. The highest estimate variation was recorded French Polynesia Southeast Asia. these reefs than elsewhere harbor adaptive potential survive climate change, so managers should prioritize when forming conservation goals.

Language: Английский

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Cryptic coral community composition across environmental gradients

PLoS ONE, Journal Year: 2025, Volume and Issue: 20(2), P. e0318653 - e0318653

Published: Feb. 6, 2025

Cryptic genetic variation is increasingly being identified in numerous coral species, with prior research indicating that different cryptic lineages can exhibit varied responses to environmental changes. This suggests a potential link between and local conditions. In this study, we investigate how communities of vary along gradients. We began by identifying within six species sampled around St. Croix, USVI based on 2b-RAD sequencing data. then analyzed associations the distributions across (i.e., “cryptic community composition”) ecoregions, or geographically distinct Our findings show depth more significant predictor composition than ecoregions most influential factor among 40 abiotic variables characterize ecoregions. These results imply are influenced both conditions, although exact factors driving these patterns remain unknown. Understanding turnover seascape important consider when outplanting corals restore reef, as locally-adapted may have differential fitness

Language: Английский

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