Coral ReefsPub Date : 2024-09-19DOI: 10.1007/s00338-024-02565-x
Lachan Roth, Tom Shlesinger, Yossi Loya
{"title":"Reproductive ecology of fire corals in the northern Red Sea","authors":"Lachan Roth, Tom Shlesinger, Yossi Loya","doi":"10.1007/s00338-024-02565-x","DOIUrl":"https://doi.org/10.1007/s00338-024-02565-x","url":null,"abstract":"<p>Scleractinian corals, the principal architects of coral reefs, face substantial threats from ongoing and anticipated climate change and other anthropogenic disturbances. This underscores the significance of investigating alternative reef-building organisms and their contribution to reefs’ resilience. Among these alternatives, colonial hydrozoans of the genus <i>Millepora</i>, commonly called ‘fire corals’, play substantial roles in contributing to coral reef structure and functionality by depositing calcareous exoskeletons. Despite the ecological importance of fire corals, fundamental knowledge gaps remain regarding their biology and reproductive ecology. Here, we present a comprehensive study on the population dynamics, reproductive ecology, phenology, and sex ratio of the three Red Sea fire corals—<i>Millepora dichotoma, M. exaesa</i>, and <i>M. platyphylla—</i>in the Gulf of Aqaba and Eilat. The abundance of <i>M. dichotoma</i> and <i>M. exaesa</i> seems to have remained consistent over the last 50 years across two of the three depth zones surveyed, indicating their potential resistance or resilience. However, at the third depth surveyed, their abundance appears to have decreased. Our extensive <i>in-situ</i> monitoring of breeding events over six consecutive years has revealed a previously undetected relationship between <i>Millepora</i> species breeding events and the lunar cycle. Histological analyses indicated remarkably short reproductive cycles of only 2–3 weeks, recurring multiple times within a single season, in both <i>M. dichotoma</i> and <i>M. exaesa,</i> which is a unique reproductive aspect compared to other reef-building corals. These results highlight the high reproductive and resilience potential of <i>Millepora</i> species. Consequently, fire corals could assume a more substantial role as keystone species in changing environments and future reefs, emphasizing their importance in reef conservation and management.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"4 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-19DOI: 10.1007/s00338-024-02564-y
Defne Sahin, Nestor E. Bosch, Chenae Cooper, Karen Filbee-Dexter, Ben Radford, Verena Schoepf, Damian P. Thomson, Thomas Wernberg
{"title":"Spatial structuring of coral traits along a subtropical-temperate transition zone persists despite localised signs of tropicalisation","authors":"Defne Sahin, Nestor E. Bosch, Chenae Cooper, Karen Filbee-Dexter, Ben Radford, Verena Schoepf, Damian P. Thomson, Thomas Wernberg","doi":"10.1007/s00338-024-02564-y","DOIUrl":"https://doi.org/10.1007/s00338-024-02564-y","url":null,"abstract":"<p>Climate-driven species range expansions are underway with more tropically affiliated species, including Scleractinian corals, becoming increasingly abundant at higher latitudes. However, uncertainty remains on how these range shifts will affect reef-scale ecosystem processes, which will ultimately depend on the traits of the taxa that dominate these assemblages. Here, we quantified spatiotemporal patterns in the taxonomic and trait structure of coral assemblages along the subtropical-temperate coast of Western Australia (27°–34°S). Coral abundance was generally low and coral cover < 5% across our study sites. Coral assemblages shared similarities in morphological trait structures across the latitudinal gradient, mostly characterised by taxa with simple morphologies; yet subtle differences were also observed across latitudes, with high-latitude corals characterised by slower growth rates and reduced maximum colony sizes. We found a 3.4-fold increase (from 1 to 3.4 individuals m<sup>−2</sup>) in coral abundance at one heavily disturbed location, where canopy-forming seaweeds were replaced by turfing algae, a pattern that was partly driven by an increase in the relative contribution of warm affinity taxa, such as <i>Acropora</i> spp. We predicted these changes would be reflected in different components of functional diversity; yet, despite a localised signal of tropicalisation, we only observed subtle changes in the functional identity, richness, evenness, and divergence. The spatially invariant trait structure of coral assemblages suggests that the nature of ecosystem functions will likely remain unchanged during early stages of tropicalisation, and hence their contribution to temperate reef-scale ecological processes will depend on dominance over other benthic foundational species.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"17 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-18DOI: 10.1007/s00338-024-02566-w
M. Aravinda Kishan Peiris, Shang-Yin Vanson Liu, Joseph D. DiBattista, Michael Bunce, Yi-Hsuan Chen, Kang-Ning Shen, Chih-Wei Chang
{"title":"eDNA metabarcoding captures a decline of coral diversity at Taiping Island after an outbreak of Crown-of-Thorns starfish","authors":"M. Aravinda Kishan Peiris, Shang-Yin Vanson Liu, Joseph D. DiBattista, Michael Bunce, Yi-Hsuan Chen, Kang-Ning Shen, Chih-Wei Chang","doi":"10.1007/s00338-024-02566-w","DOIUrl":"https://doi.org/10.1007/s00338-024-02566-w","url":null,"abstract":"<p>Coral reefs are known to be one of the most diverse marine ecosystems on earth. However, these important ecosystems are heavily stressed by natural and anthropogenic activities. Environmental DNA (eDNA) metabarcoding is an innovative approach that can provide a greater diversity of taxonomic detections, non-invasive sampling, and a lower field component cost than traditional biomonitoring methods. Taiping Island (Itu Aba Island) is one of the major coral reef islands situated in the South China Sea where underwater visual surveys documented an outbreak of Crown-of-Thorns starfish (COTS) in 2021. In our study, we used eDNA metabarcoding to investigate whether there were shifts in coral communities by comparing pre- and post-COTS outbreak communities. One metabarcoding assay targeting the 18S gene and two assays targeting the ITS2 region (one of these assays specifically targeting Acroporid corals) were applied to 42 seawater samples collected in 2019 and 2021 from 12 sites around Taiping Island. Based on these three metabarcoding assays, 52 unique hard coral species were identified, corresponding to a total of 51 species in 2019 and 26 species in 2021. Our results indicated a significant decline in coral diversity but an increase in sponge diversity from the phylum porifera at Taiping Island in 2021. We suggest that these faunal shifts may be due to active feeding and disturbance of COTS at outbreak proportions that result in habitat changes. Our findings also suggest that eDNA can continue to serve as a promising tool to monitor the change in coral as well as reef-associated taxa during devastating outbreak events.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"55 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-16DOI: 10.1007/s00338-024-02540-6
Tries B. Razak, Ravienkha R. Budaya, Frensly D. Hukom, Beginer Subhan, Fathia K. Assakina, Shifa Fauziah, Haifa H. Jasmin, Rindah Talitha Vida, Cut Aja Gita Alisa, Rizya Ardiwijaya, Alan T. White, Sterling B. Tebbett
{"title":"Long-term dynamics of hard coral cover across Indonesia","authors":"Tries B. Razak, Ravienkha R. Budaya, Frensly D. Hukom, Beginer Subhan, Fathia K. Assakina, Shifa Fauziah, Haifa H. Jasmin, Rindah Talitha Vida, Cut Aja Gita Alisa, Rizya Ardiwijaya, Alan T. White, Sterling B. Tebbett","doi":"10.1007/s00338-024-02540-6","DOIUrl":"https://doi.org/10.1007/s00338-024-02540-6","url":null,"abstract":"<p>Most comparative studies assessing reef health focus on living hard coral cover as the key metric. In Indonesia, in situ monitoring of coral cover has been ongoing for over five decades. However, as monitoring data and research findings are predominantly published in the local language (Bahasa Indonesia), local data often escape global attention, resulting in Indonesian coral reefs receiving less scientific attention despite accounting for ~ 15% of all coral reef area globally. Here, we systematically compiled both globally and locally published data on coral cover across Indonesia to assess changes over recent decades. We analysed 7,614 data entries extracted from 621 publications and found that the majority (79.1%) of the publications were written in Bahasa Indonesia, constituting 63.4% of the total data entries. Our dataset revealed limited evidence of net declines in coral cover over the last three decades (1994–2022). There was also no clear relationship between coral cover and human density, as well as with the thirteen environmental/anthropogenic drivers examined. We discuss several factors that may contribute to this lack of detectable large-scale change including: recent data potentially representing a ‘shifted baseline’; the ‘averaging out’ of localised changes in coral cover dynamics at a broad scale; sampling biases; and/or the potential resilience of Indonesian coral reefs compared to other regions. This study highlights the wealth of accessible local coral reef data published in languages other than English and emphasises the importance of using such data to enhance our understanding of the long-term dynamics of coral reef ecosystems worldwide.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"49 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142258359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-11DOI: 10.1007/s00338-024-02556-y
David R. Bellwood, Sterling B. Tebbett
{"title":"Habitat trumps biogeography in structuring coral reef fishes","authors":"David R. Bellwood, Sterling B. Tebbett","doi":"10.1007/s00338-024-02556-y","DOIUrl":"https://doi.org/10.1007/s00338-024-02556-y","url":null,"abstract":"<p>As one of the world’s most diverse ecosystems, coral reefs have been the focus of numerous biogeographic analyses. With strong biodiversity gradients across the Indo-Pacific, coral reefs have shed light on the effects of evolutionary history, isolation, and human exploitation on local assemblages. However, there are also strong environmentally driven local gradients in faunal assemblages. We ask, does reef fish community composition and trait space vary to a greater extent across small scales (i.e. along habitat gradients) or across large scales (i.e. across geographic regions separated by up to 12,000 km)? Using a standardized survey method that explicitly includes habitats (i.e. the slope, crest, and flat), we surveyed a highly diverse family of reef fishes (Labridae) in nine regions across the Indo-Pacific, from the Cocos (Keeling) Islands to French Polynesia. We demonstrate that small-scale habitat gradients represent a greater axis of variation, in both the taxonomic and trait composition of fish assemblages, than large-scale biogeographic gradients. Indeed, fish assemblages just 10 m apart, along a habitat gradient, appear to differ more than assemblages in the same habitats separated by over 12,000 km along the world’s largest biodiversity gradient. Essentially, fish assemblages cluster by habitat regardless of their biogeographic region, with habitat associations trumping biogeographic affiliations. This emphasizes the primacy of local environmental factors, such as hydrodynamics, in shaping the ecology of reef fishes. It also raises serious concerns over the use of combined datasets, where data from different habitats are used, without explicit recognition, in global-scale analyses.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"31 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-06DOI: 10.1007/s00338-024-02548-y
Danijela Dimitrijević, Nadia Santodomingo, Wolfgang Kiessling
{"title":"Reef refugia in the aftermath of past episodes of global warming","authors":"Danijela Dimitrijević, Nadia Santodomingo, Wolfgang Kiessling","doi":"10.1007/s00338-024-02548-y","DOIUrl":"https://doi.org/10.1007/s00338-024-02548-y","url":null,"abstract":"<p>In the face of rising global temperatures, coral reefs experience coral mass bleaching and mortality. Subtropical and mesophotic environments may represent refugia for reef corals under climate change, where they can survive and eventually recolonize degraded areas. Using a comprehensive database of fossil reefs, we empirically assess the efficacy of subtropical, deeper, and turbid mesophotic environments to restore coral reefs after past global warming events. We focus on tropical coral reefs over the last 275 million years and four rapid climate warming events, which coincided with global reef crises in the geological record. In the aftermath of such hyperthermal events, we observed an increase in the proportions of reefs occurring in deeper (blue) mesophotic environments. Additionally, we found a trend of reef distributions and coral shifting towards higher latitudes. The number of coral occurrences in turbid (brown mesophotic) environments also increased after hyperthermal events. Our results suggest that subtropical, blue, and brown mesophotic environments may have served as immediate refugia for shallow-water coral species escaping warming seawater. While the patterns of reef range shifts and the establishment of blue and brown mesophotic refugia following ancient hyperthermal events provide some hope for coral reefs under current climate change, re-establishement of background reef conditions took most times millions of years.</p><br/><p>Ante el incremento de temperatura global, los arrecifes coralinos están experimentando eventos masivos de blanqueamiento y mortalidad. Los ambientes subtropicales y mesofóticos pueden representar refugios para los corales arrecifales, en los cuales pueden escapar de los efectos del cambio climático, sobrevivir y desde allí recolonizar áreas previamente degradadas. Mediante el uso de una exhaustiva base de datos en arrecifes coralinos, en este estudio se evaluó empíricamente la eficacia de los ambientes subtropicales y mesofóticos, tanto de aguas turbias someras (marrones) como de aguas claras profundas (azules), en la recuperación de arrecifes coralinos después de eventos hipertermales en el pasado. Nuestro enfoque estuvo en los arrecifes coralinos tropicales durante los últimos 275 millones de años y cuatro eventos de calentamiento climático rápido, los cuales coinciden con crisis globales en la ocurrencia de arrecifes en el registro fósil. Como consecuencia de dichos eventos hipertermales, observamos un aumento del número de arrecifes en ambientes mesofóticos de aguas profundas (azules). Además, encontramos una tendencia en la distribución de arrecifes y corales que se desplazan hacia latitudes más altas. También se observó un aumento en el número de corales que estuvieron presentes en ambientes de aguas turbias (marrones) después de dichos eventos hipertermales. Nuestros resultados sugieren que, en el pasado, los ambientes subtropicales, mesofóticos azules y mesofóticos marrones pudieron haber servid","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"2 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-05DOI: 10.1007/s00338-024-02559-9
Ryan N. Jones
{"title":"Habitat partitioning by two coral-dwelling scorpionfishes in Hawai‘i","authors":"Ryan N. Jones","doi":"10.1007/s00338-024-02559-9","DOIUrl":"https://doi.org/10.1007/s00338-024-02559-9","url":null,"abstract":"<p>Coral reefs are among the most biodiverse ecosystems on Earth, largely due to the structural complexity created by corals. Coral habitat is crucial refuge for numerous small animals, and competition for habitat can structure populations if in short supply. Reefs in Hawai‘i are largely dominated by the small branching coral <i>Pocillopora meandrina</i>, which supports diverse communities of fishes and invertebrates. Two species of nocturnal scorpionfishes, <i>Sebastapistes coniorta</i> and <i>S</i>. <i>galactacma</i>, are particularly common in <i>P</i>. <i>meandrina</i>, inhabiting the complex branching morphology of their host corals during the day and feeding in and around these corals at night. Surveys of scorpionfishes in 458 <i>P</i>. <i>meandrina</i> between 3 and 22 m deep along the south and west shores of O‘ahu revealed inverse depth distributions over which these species occurred in <i>P</i>. <i>meandrina</i>. <i>Sebastapistes coniorta</i> almost exclusively occurred in coral colonies between 5 and 10 m deep, while <i>S</i>. <i>galactacma</i> were found across all depths surveyed, though were far more common and abundant in deeper coral colonies (15–20 m) below the range of <i>S</i>. <i>coniorta</i>. Further, measurements of host colony morphometrics revealed that these species appeared to use microhabitat in subtly different ways. The larger-bodied species, <i>S</i>. <i>coniorta</i>, was more commonly found in <i>P</i>. <i>meandrina</i> with wider spaces between branches, while the smaller-bodied species was negatively associated with wider branch spacing. These patterns indicate habitat partitioning between <i>S</i>. <i>coniorta</i> and <i>S</i>. <i>galactacma</i> at both the reef and colony scale, which may explain how these species are able to coexist on reefs in Hawai‘i.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"26 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-03DOI: 10.1007/s00338-024-02553-1
Christine D. Roper, Jennifer L. Matthews, Emma F. Camp, Matthew P. Padula, Unnikrishnan Kuzhiumparambil, John Edmondson, Lorna Howlett, David J. Suggett
{"title":"Lipid composition of coral propagules and reproductive material in coral restoration nurseries","authors":"Christine D. Roper, Jennifer L. Matthews, Emma F. Camp, Matthew P. Padula, Unnikrishnan Kuzhiumparambil, John Edmondson, Lorna Howlett, David J. Suggett","doi":"10.1007/s00338-024-02553-1","DOIUrl":"https://doi.org/10.1007/s00338-024-02553-1","url":null,"abstract":"<p>Coral restoration efforts have rapidly increased worldwide, including the development of several programmes on the Great Barrier Reef (GBR) in recent years. While many restoration programmes utilise in-water nurseries to accelerate coral biomass yields, the impact of nursery environments on propagule quality has not been examined despite the importance of coral fitness for ensuring resistant populations. Here, we investigated two fitness indicators (lipid diversity and tissue protein abundance) of <i>Acropora millepora</i> adults and eggs grown on coral nurseries versus native reef on the GBR, with adults assessed at two sites (Blue Lagoon and Rayban) and eggs assessed at one site (Blue Lagoon). Lipid profiles of adult colonies varied by site and origin (nursery versus wild reef), with adult nursery corals exhibiting an elevated relative abundance of storage lipids (diacylglycerols and triacylglycerols) and lipid classes responsible for regulating membrane structure (phosphatidylcholines and sterol esters), while wild corals were characterised by a greater relative abundance of fatty acids and classes involved in immunoregulation. Comparing eggs from different origins, nursery offspring were richer in energy-storing triacylglycerols, as well as ceramides and phosphatidylcholines essential for membrane structure, while wild eggs had a greater relative abundance of wax ester species also important for energy storage. No differences were found in total protein abundance (adult or eggs) or egg physical characteristics (count and size) between nursery and wild origins. Variations in lipid profiles are consistent with differences in environmental conditions between reef sites and origin (nursery versus wild), highlighting the need to consider site selection and propagation conditions when planning restoration projects. Importantly, these findings demonstrate that the lipid classes with the highest relative abundance in <i>A. millepora</i> nursery and wild eggs differed from those in adults from the same origin, suggesting that propagation origin is more important for driving lipid profiles in coral eggs compared to parental effects.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"18 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coral ReefsPub Date : 2024-09-02DOI: 10.1007/s00338-024-02549-x
Nuba Zamora-Jordán, Pedro Martínez Martínez, Mariano Hernández, Cataixa López
{"title":"Responses of Palythoa caribaeorum and its associated endosymbionts to thermal stress","authors":"Nuba Zamora-Jordán, Pedro Martínez Martínez, Mariano Hernández, Cataixa López","doi":"10.1007/s00338-024-02549-x","DOIUrl":"https://doi.org/10.1007/s00338-024-02549-x","url":null,"abstract":"<p>In recent years, several studies have highlighted the high resilience of zoantharians to ocean warming. In particular, populations of <i>Palythoa caribaeorum</i> are proliferating and beginning to dominate the coastal ecosystems of the Canary Islands. This expansion has been associated with increasing sea surface temperatures (SSTs). Here, we provide new insights into the endosymbiont-<i>P. caribaeorum</i> associations during and after a heat stress experiment to understand the processes underlying their high resilience to elevated temperatures. For this purpose, 61 colonies collected in the Canary Islands were exposed to an increasing temperature gradient (from 24 to 32 °C) to assess their heat tolerance, and then transferred back to the control temperature (24 °C) to evaluate their resilience. Colonies performance was assessed by comparing host color changes (bleaching degree), analyzing their Symbiodiniaceae morphological condition, and determining the dominant lineage of Symbiodiniaceae using the psbA<sub>ncr</sub> molecular marker. All colonies showed signs of bleaching during heat stress, evidenced by color loss and a decrease in healthy Symbiodiniaceae content. Nevertheless, <i>P. caribaeorum</i> showed high resistance to heat stress, as all colonies kept up to 30 °C were able to survive and significantly recover. Furthermore, as the experimental temperature increased, a new haplotype of the <i>Cladocopium</i> C1 lineage, not detected in the control and wild samples, emerged and dominated most of the colonies (59.09%). Our study demonstrates the resilience of <i>P. caribaeorum</i> to heat stress in the Canary Islands, raising important ecological concerns about the future of native macroalgae ecosystems in an ocean warming scenario.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"22 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spawning window and fecundity in three Acroporid corals from the environmentally variable semi-enclosed lagoon of Bouraké","authors":"Cinzia Alessi, Carly J. Randall, Mahe Dumas, Hugues Lemonnier, Riccardo Rodolfo-Metalpa","doi":"10.1007/s00338-024-02551-3","DOIUrl":"https://doi.org/10.1007/s00338-024-02551-3","url":null,"abstract":"<p>The gametogenic cycle in broadcast spawning corals takes several months, with oogenesis culminating in synchronized maturation when seawater temperatures rise. Temperature is known for governing reproductive seasonality, yet little is known about how multiple stressors may affect spawning timing. The semi-enclosed lagoon of Bouraké in New Caledonia is subjected to high fluctuations in seawater temperature, pH, salinity, and oxygen, representing an ideal playground to explore possible effects of extreme environmental variability on coral gametogenesis. Here, the spawning window and fecundity metrics (i.e., colony- and polyp-level fecundity, and egg size) of <i>Acropora tenuis, Montipora digitata</i>, and <i>M. stellata</i> from Bouraké were compared with four reference sites located at variable distances from Bouraké. Results suggest that Bouraké and its nearby control site largely spawned synchronously, but there was a spawning asynchrony between Bouraké and the sites further south, in all three species. Interestingly, no reduction in the number of eggs per fecund polyp or number of fecund polyps was observed in Bouraké compared with the reference sites, in any species. However, <i>A. tenuis</i> and <i>M. digitata</i> had smaller eggs in Bouraké compared to reference sites, with possible repercussions for coral fitness. In conclusion, some reproductive traits are maintained in coral species inhabiting a highly variable environment, but smaller gametes may alter population recovery processes. Furthermore, since our data are limited to 2 yrs of observations, spawning synchronization between Bouraké and its surroundings warrant continued investigation to determine whether coral colonies from this area harbor traits that increase fitness under future climate scenarios.</p>","PeriodicalId":10821,"journal":{"name":"Coral Reefs","volume":"11 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142181503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}