1
|
Liu C, Zhang Y, Botana MT, Fu Y, Huang L, Jiang L, Yu X, Luo Y, Huang H. The bioenergetics response of the coral Pocillopora damicornis to temperature changes during its reproduction stage. MARINE ENVIRONMENTAL RESEARCH 2024; 198:106557. [PMID: 38823094 DOI: 10.1016/j.marenvres.2024.106557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 04/21/2024] [Accepted: 05/14/2024] [Indexed: 06/03/2024]
Abstract
Sexual reproduction of reef-building corals is vital for coral reef ecosystem recovery. Corals allocate limited energy to growth and reproduction, when being under environmental disturbance, which ultimately shapes the community population dynamics. In the present study, energetic and physiological parameters of both parental colonies and larvae of the coral Pocillopora damicornis were measured during their reproduction stage under four temperatures; 28 °C (low-temperature acclimation, LA), 29 °C (control temperature, CT), 31 °C (high-temperature acclimation, HA), and 32 °C (heat stress, HS). The results showed temperature changes altered the larvae release timing and fecundity in P. damicornis. Parental colonies exposed to the LA treatment exhibited reduced investment in reproduction and released fewer larvae, while retaining more energy for their development. However, each larva acquired higher energy and symbiont densities enabling survival through longer planktonic periods before settlement. In contrast, parental colonies exposed to the HA treatment had increased investment for reproduction and larvae output, while per larva gained less energy to mitigate the threat of higher temperature. Furthermore, the energy allocation processes restructured fatty acids concentration and composition in both parental colonies and larvae as indicated by shifts in membrane fluidity under adaptable temperature changes. Notably, parental colonies from the HS treatment expended more energy in response to heat stress, resulting in adverse effects, especially after larval release. Our study expands the current knowledge on the energy allocation strategies of P. damicornis and how it is impacted by temperature. Parental colonies employed different energy allocation strategies under distinct temperature regimes to optimize their development and offspring success, but under heat stress, both were compromised. Lipid metabolism is essential for the success of coral reproduction and further understanding their response to heat stress can improve intervention strategies for coral reef conservation in warmer future oceans.
Collapse
Affiliation(s)
- Chengyue Liu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; Department of Ocean Science and Hong Kong Branch (HKB) of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology (HKUST), Hong Kong, China.
| | - Yuyang Zhang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Marina Tonetti Botana
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Yousi Fu
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA
| | - Lintao Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Lei Jiang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; Department of Ocean Science and Hong Kong Branch (HKB) of the Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology (HKUST), Hong Kong, China
| | - Xiaolei Yu
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Yong Luo
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, USA; CAS-HKUST Sanya Joint Laboratory of Marine Science Research, Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya, China
| | - Hui Huang
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Provincial Key Laboratory of Applied Marine Biology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China; CAS-HKUST Sanya Joint Laboratory of Marine Science Research, Key Laboratory of Tropical Marine Biotechnology of Hainan Province, Sanya Institute of Oceanology, SCSIO, Sanya, China; Sanya National Marine Ecosystem Research Station, Tropical Marine Biological Research Station in Hainan, Chinese Academy of Sciences, Sanya, China.
| |
Collapse
|
2
|
Johnston EC, Caruso C, Mujica E, Walker NS, Drury C. Complex parental effects impact variation in larval thermal tolerance in a vertically transmitting coral. Heredity (Edinb) 2024; 132:275-283. [PMID: 38538721 PMCID: PMC11167003 DOI: 10.1038/s41437-024-00681-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 03/12/2024] [Accepted: 03/14/2024] [Indexed: 06/13/2024] Open
Abstract
Coral populations must be able to adapt to changing environmental conditions for coral reefs to persist under climate change. The adaptive potential of these organisms is difficult to forecast due to complex interactions between the host animal, dinoflagellate symbionts and the environment. Here we created 26 larval families from six Montipora capitata colonies from a single reef, showing significant, heritable variation in thermal tolerance. Our results indicate that 9.1% of larvae are expected to exhibit four times the thermal tolerance of the general population. Differences in larval thermotolerance were driven mainly by maternal contributions, but we found no evidence that these effects were driven by symbiont identity despite vertical transmission from the dam. We also document no evidence of reproductive incompatibility attributable to symbiont identity. These data demonstrate significant genetic variation within this population which provides the raw material upon which natural selection can act.
Collapse
Affiliation(s)
- Erika C Johnston
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI, USA.
| | - Carlo Caruso
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI, USA
| | - Elena Mujica
- Department of Bioengineering, University of California, Berkeley, CA, USA
| | - Nia S Walker
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI, USA
| | - Crawford Drury
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI, USA
| |
Collapse
|
3
|
Jones NP, Gilliam DS. Temperature and local anthropogenic pressures limit stony coral assemblage viability in southeast Florida. MARINE POLLUTION BULLETIN 2024; 200:116098. [PMID: 38310721 DOI: 10.1016/j.marpolbul.2024.116098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 01/07/2024] [Accepted: 01/28/2024] [Indexed: 02/06/2024]
Abstract
Climate change is viewed as the primary threat to coral reefs, with local pressures exacerbating coral cover decline. The consensus is that improving water quality may increase resilience, but disentangling water quality and temperature impacts is difficult. We used distance-based linear models and random forests to analyze spatiotemporal variation in benthic community structure and interannual changes in the coral assemblage, in relation to specific environmental metrics in Southeast Florida. Temperature accounted for most of the variation, recruitment doubled and interannual increases in coral abundance tripled when mean annual temperature reached 27 °C, until maximum temperatures exceeded 31 °C. Benefits associated with warmer temperatures were negated by poor water quality, as nutrient enrichment was related to increased macroalgal cover, reduced coral recruitment and higher coral partial mortality. We suggest reducing local pressures will contribute to reduced macroalgae and enhance coral recovery, but that temperature is the predominant influence on coral assemblages.
Collapse
Affiliation(s)
- Nicholas P Jones
- National Coral Reef Institute, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 N Ocean Drive, Dania Beach, FL 33004, USA.
| | - David S Gilliam
- National Coral Reef Institute, Halmos College of Arts and Sciences, Nova Southeastern University, 8000 N Ocean Drive, Dania Beach, FL 33004, USA
| |
Collapse
|
4
|
Alessi C, Lemonnier H, Camp EF, Wabete N, Payri C, Rodolfo Metalpa R. Algal symbiont diversity in Acropora muricata from the extreme reef of Bouraké associated with resistance to coral bleaching. PLoS One 2024; 19:e0296902. [PMID: 38416713 PMCID: PMC10901360 DOI: 10.1371/journal.pone.0296902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 12/21/2023] [Indexed: 03/01/2024] Open
Abstract
Widespread coral bleaching has generally been linked to high water temperatures at larger geographic scales. However, the bleaching response can be highly variable among individual of the same species, between different species, and across localities; what causes this variability remains 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 where conditions are more benign. We describe Symbiodiniaceae community changes based on next-generation sequencing of the ITS2 marker, metabolic responses, and energetic reserve measures (12 physiological traits evaluated) during the La Niña warm and rainy summer in 2021. Widespread coral bleaching (score 1 and 2 on the coral colour health chart) was observed only in Bouraké, likely due to the combination of the high temperatures (up to 32°C) and heavy rain. All colonies (i.e., Bouraké and reference site) associated predominantly with Symbiodinaceae from the genera Cladocopium. 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 the reef control colonies during the stress event. After four months, the few bleached colonies that survived in Bouraké (B2) acquired the same ITS2 type profiles of the unbleached colonies in Bouraké. In terms of physiological performances, all bleached corals showed metabolic depression (e.g., Pgross and Rdark). In contrast, unbleached 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 associations, while energetic reserves may increase their resilience after stress.
Collapse
Affiliation(s)
- Cinzia Alessi
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
- Laboratoire d'Excellence CORAIL, ENTROPIE (UMR9220), IRD, Nouméa, New Caledonia
| | - Hugues Lemonnier
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
- Laboratoire d'Excellence CORAIL, ENTROPIE (UMR9220), IRD, Nouméa, New Caledonia
| | - Emma F Camp
- Climate Change Cluster, University of Technology, Ultimo, NSW, Australia
| | - Nelly Wabete
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
| | - Claude Payri
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
- Laboratoire d'Excellence CORAIL, ENTROPIE (UMR9220), IRD, Nouméa, New Caledonia
| | - Riccardo Rodolfo Metalpa
- ENTROPIE, IRD, Université de la Réunion, CNRS, IFREMER, Université de Nouvelle-Calédonie, Nouméa, New Caledonia
- Laboratoire d'Excellence CORAIL, ENTROPIE (UMR9220), IRD, Nouméa, New Caledonia
- Labex ICONA International CO2 Natural Analogues Network, Shimoda, Japan
| |
Collapse
|
5
|
Adaptations by the coral Acropora tenuis confer resilience to future thermal stress. Commun Biol 2022; 5:1371. [PMID: 36517561 PMCID: PMC9751277 DOI: 10.1038/s42003-022-04309-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Elevated temperatures cause coral bleaching and reef degradation. However, coral may have strategies to survive by reproducing more heat-tolerable larvae. We examine the direct and carryover effects of thermal stress on fecundity and fitness in the reef-building coral Acropora tenuis. Fragments from the same colony are subjected to control temperature (~27.5 °C) or heat stress (~31 °C) for ten days. We then examine the fecundity of adults (egg number and size) and the thermal tolerance of larvae and recruits (survival rates, growth, and size). The stressed fragments show a trade-off in egg production, an increase in egg number but a decrease in size. In addition, larvae and recruits from the stressed colony show marginally higher survival rates in the higher water temperature but do not differ in the control condition. Therefore, corals produce more heat-resistant larvae and recruits after they experience heat stress, which may improve coral reef resilience.
Collapse
|
6
|
Howells EJ, Hagedorn M, Van Oppen MJ, Burt JA. Challenges of sperm cryopreservation in transferring heat adaptation of corals across ocean basins. PeerJ 2022; 10:e13395. [PMID: 35651741 PMCID: PMC9150692 DOI: 10.7717/peerj.13395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/16/2022] [Indexed: 01/14/2023] Open
Abstract
Reef-building corals live very close to their upper thermal limits and their persistence is imperiled by a rapidly warming climate. Human interventions may be used to increase the thermal limits of sensitive corals by cross-breeding with heat-adapted populations. However, the scope of breeding interventions is constrained by regional variation in the annual reproductive cycle of corals. Here we use cryopreservation technology to overcome this barrier and cross-breed conspecific coral populations across ocean basins for the first time. During regional spawning events, sperm samples were cryopreserved from populations of the widespread Indo-Pacific coral, Platygyra daedalea, from the southern Persian Gulf (maximum daily sea surface temperature of 36 °C), the Oman Sea (33 °C), and the central Great Barrier Reef (30 °C). These sperm samples were thawed during a later spawning event to test their ability to fertilize freshly spawned eggs of P. daedalea colonies from the central Great Barrier Reef. Average fertilization success for the Persian Gulf (9%) and Oman Sea (6%) sperm were 1.4-2.5 times lower than those for the native cryopreserved sperm from Great Barrier Reef (13-15%), potentially due to lower sperm quality of the Middle Eastern sperm and/or reproductive incompatibility between these distant populations. Overall, fertilization success with cryopreserved sperm was low compared with fresh sperm (>80%), likely due to the low motility of thawed sperm (≤5%, reduced from 50% to >90% in fresh sperm). To evaluate whether cross-bred offspring had enhanced thermal tolerance, the survival of larvae sired by Persian Gulf cryopreserved sperm, Great Barrier Reef cryopreserved sperm, and Great Barrier Reef fresh sperm was monitored for six days at ambient (27 °C) and elevated (33 °C) temperature. Against expectations of thermal tolerance enhancement, survival of larvae sired by Persian Gulf cryopreserved sperm was 2.6 times lower than larvae sired by Great Barrier Reef fresh sperm at 33 °C (27% versus 71%), but did not differ at 27 °C (77% versus 84%). This lack of enhanced thermal tolerance was unlikely due to outbreeding depression as survival was equally poor in larvae sired by Great Barrier Reef cryopreserved sperm. Rather, follow-up tests showed that cryoprotectant exposure during fertilization (0.1% DMSO) has a negative effect on the survival of P. daedalea larvae which is exacerbated at elevated temperature. Collectively, our findings highlight challenges of breeding corals for enhanced thermal tolerance using cryopreserved sperm, which may be overcome by methodological advances in the collection and preservation of high-quality motile sperm and minimizing the exposure time of eggs to cryoprotectants.
Collapse
Affiliation(s)
- Emily J. Howells
- Water Research Center and Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates,National Marine Science Centre, Faculty of Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
| | - Mary Hagedorn
- Center for Species Survival, Smithsonian Conservation Biology Institute, Smithsonian Institution, Free Royal, Virginia, United States of America,Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, Hawaii, United States of America
| | - Madeleine J.H. Van Oppen
- School of Biocsiences, The University of Melbourne, Melbourne, Victoria, Australia,Australian Institute of Marine Science, Townsville, Queenslabd, Australia
| | - John A. Burt
- Water Research Center and Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| |
Collapse
|
7
|
Bejarano I, Orenes-Salazar V, Bento R, García-Charton JA, Mateos-Molina D. Coral reefs at Sir Bu Nair Island: An offshore refuge of Acropora in the southern Arabian Gulf. MARINE POLLUTION BULLETIN 2022; 178:113570. [PMID: 35349864 DOI: 10.1016/j.marpolbul.2022.113570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/04/2022] [Accepted: 03/12/2022] [Indexed: 06/14/2023]
Abstract
Coral reefs across the southern Arabian Gulf have declined in the past two decades, with extensive loss of formerly Acropora table corals, which are now functionally extinct in nearshore reefs. This study documents the coral community at Sir Bu Nair (SBN), an offshore island buffered by less extreme environmental conditions, which contains the last remaining large stands of Acropora in the southern Gulf. We found that Acropora is a major reef-building coral throughout SBN. Mean coral cover was 27% (range: 6%-49%) across all sites and depths, of which more than half was comprised by Acropora. This varied around the island, with the highest densities to the south and southwest in shallow waters. Our study provides essential information for the management and conservation of these highly valuable and vulnerable corals.
Collapse
Affiliation(s)
- Ivonne Bejarano
- Department of Biology, Chemistry and Environmental Sciences Department, American University of Sharjah, 26666, Sharjah, United Arab Emirates
| | - Victor Orenes-Salazar
- Departamento de Ecología e Hidrología, Universidad de Murcia, Campus Espinardo, 30100, Murcia, Spain
| | - Rita Bento
- Emirates Nature - World Wide Fund for Nature (Emirates Nature-WWF), P.O. Box 23304, Dubai, United Arab Emirates
| | | | - Daniel Mateos-Molina
- Departamento de Ecología e Hidrología, Universidad de Murcia, Campus Espinardo, 30100, Murcia, Spain; Emirates Nature - World Wide Fund for Nature (Emirates Nature-WWF), P.O. Box 23304, Dubai, United Arab Emirates.
| |
Collapse
|
8
|
Doropoulos C, Gómez-Lemos LA, Salee K, McLaughlin MJ, Tebben J, Van Koningsveld M, Feng M, Babcock RC. Limitations to coral recovery along an environmental stress gradient. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2022; 32:e2558. [PMID: 35112758 DOI: 10.1002/eap.2558] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 11/09/2021] [Accepted: 11/16/2021] [Indexed: 06/14/2023]
Abstract
Positive feedbacks driving habitat-forming species recovery and population growth are often lost as ecosystems degrade. For such systems, identifying mechanisms that limit the re-establishment of critical positive feedbacks is key to facilitating recovery. Theory predicts the primary drivers limiting system recovery shift from biological to physical as abiotic stress increases, but recent work has demonstrated that this seldom happens. We combined field and laboratory experiments to identify variation in limitations to coral recovery along an environmental stress gradient at Ningaloo Reef and Exmouth Gulf in northwest Australia. Many reefs in the region are coral depauperate due to recent cyclones and thermal stress. In general, recovery trajectories are prolonged due to limited coral recruitment. Consistent with theory, clearer water reefs under low thermal stress appear limited by biological interactions: competition with turf algae caused high mortality of newly settled corals and upright macroalgal stands drove mortality in transplanted juvenile corals. Laboratory experiments showed a positive relationship between crustose coralline algae cover and coral settlement, but only in the absence of sedimentation. Contrary to expectation, coral recovery does not appear limited by the survival or growth of recruits on turbid reefs under higher thermal stress, but to exceptionally low larval supply. Laboratory experiments showed that larval survival and settlement are unaffected by seawater quality across the study region. Rather, connectivity models predicted that many of the more turbid reefs in the Gulf are predominantly self seeded, receiving limited supply under degraded reef states. Overall, we find that the influence of oceanography can overwhelm the influences of physical and biological interactions on recovery potential at locations where environmental stressors are high, whereas populations in relatively benign physical conditions are predominantly structured by local ecological drivers. Such context-dependent information can help guide expectations and assist managers in optimizing strategies for spatial conservation planning for system recovery.
Collapse
Affiliation(s)
| | - Luis A Gómez-Lemos
- Universidad Nacional de Colombia - Sede de La Paz - Escuela de Pregrados, La Paz, Colombia
| | - Kinam Salee
- CSIRO Oceans and Atmosphere, St Lucia, Queensland, Australia
| | | | - Jan Tebben
- Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
| | - Mark Van Koningsveld
- Van Oord Dredging and Marine Contractors B.V., Rotterdam, The Netherlands
- Ports and Waterways, Delft University of Technology, Delft, The Netherlands
| | - Ming Feng
- CSIRO Oceans and Atmosphere, St Lucia, Queensland, Australia
| | | |
Collapse
|
9
|
Ding DS, Wang SH, Sun WT, Liu HL, Pan CH. The Effect of Feeding on Briareum violacea Growth, Survival and Larval Development under Temperature and Salinity Stress. BIOLOGY 2022; 11:410. [PMID: 35336784 PMCID: PMC8945342 DOI: 10.3390/biology11030410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
In recent years, climate change has often caused fluctuations in seawater salinity and temperature, which threaten the survival and growth of corals. Effectively improving the stress response to temperature and salinity changes in corals to prevent bleaching is one of the important issues. This study initially explored the use of artificial polyunsaturated fatty acids to assess the ability of Briareum violacea to slow bleaching, enhance growth, stabilize larval development and reduce antistress factors (superoxide dismutase and catalase) when they were exposed to temperature and salinity stress. The salinities used in the experiment were 25, 30, 35 and 40 psu, and the temperatures were 20, 25 and 30 °C. It was divided into two parts: Experiment 1-Effects of temperature and salinity and feeding on digestive enzymes, reproduction and stress response of B. violacea; Experiment 2-Effects of temperature and salinity and feeding on the settlement and survival of larvae. The results showed that the feeding treatment group reduced the superoxide dismutase, catalase and mortality of corals under stress and significantly improved larval development and larval settlement.
Collapse
|
10
|
Matsuda SB, Chakravarti LJ, Cunning R, Huffmyer AS, Nelson CE, Gates RD, van Oppen MJH. Temperature-mediated acquisition of rare heterologous symbionts promotes survival of coral larvae under ocean warming. GLOBAL CHANGE BIOLOGY 2022; 28:2006-2025. [PMID: 34957651 PMCID: PMC9303745 DOI: 10.1111/gcb.16057] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 12/04/2021] [Accepted: 12/07/2021] [Indexed: 06/14/2023]
Abstract
Reef-building corals form nutritional symbioses with endosymbiotic dinoflagellates (Symbiodiniaceae), a relationship that facilitates the ecological success of coral reefs. These symbionts are mostly acquired anew each generation from the environment during early life stages ("horizontal transmission"). Symbiodiniaceae species exhibit trait variation that directly impacts the health and performance of the coral host under ocean warming. Here, we test the capacity for larvae of a horizontally transmitting coral, Acropora tenuis, to establish symbioses with Symbiodiniaceae species in four genera that have varying thermal thresholds (the common symbiont genera, Cladocopium and Durusdinium, and the less common Fugacium and Gerakladium). Over a 2-week period in January 2018, a series of both no-choice and four-way choice experiments were conducted at three temperatures (27, 30, and 31°C). Symbiont acquisition success and cell proliferation were measured in individual larvae. Larvae successfully acquired and maintained symbionts of all four genera in no-choice experiments, and >80% of larvae were infected with at least three genera when offered a four-way choice. Unexpectedly, Gerakladium symbionts increased in dominance over time, and at high temperatures outcompeted Durusdinium, which is regarded as thermally tolerant. Although Fugacium displayed the highest thermal tolerance in culture and reached similar cell densities to the other three symbionts at 31°C, it remained a background symbiont in choice experiments, suggesting host preference for other symbiont species. Larval survivorship at 1 week was highest in larvae associated with Gerakladium and Fugacium symbionts at 27 and 30°C, however at 31°C, mortality was similar for all treatments. We hypothesize that symbionts that are currently rare in corals (e.g., Gerakladium) may become more common and widespread in early life stages under climate warming. Uptake of such symbionts may function as a survival strategy in the wild, and has implications for reef restoration practices that use sexually produced coral stock.
Collapse
Affiliation(s)
- Shayle B. Matsuda
- Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at MānoaKāne‘oheHawai‘iUSA
| | | | - Ross Cunning
- Daniel P. Haerther Center for Conservation and ResearchJohn G. Shedd AquariumChicagoIllinoisUSA
| | - Ariana S. Huffmyer
- Department of Biological SciencesUniversity of Rhode IslandKingstonRhode IslandUSA
| | - Craig E. Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and EducationDepartment of Oceanography and Sea Grant College ProgramUniversity of Hawai‘i at MānoaHonoluluHawai‘iUSA
| | - Ruth D. Gates
- Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at MānoaKāne‘oheHawai‘iUSA
| | - Madeleine J. H. van Oppen
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
- School of BioSciencesThe University of MelbourneParkvilleVictoriaAustralia
| |
Collapse
|
11
|
Leinbach SE, Speare KE, Rossin AM, Holstein DM, Strader ME. Energetic and reproductive costs of coral recovery in divergent bleaching responses. Sci Rep 2021; 11:23546. [PMID: 34876599 PMCID: PMC8651640 DOI: 10.1038/s41598-021-02807-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 11/23/2021] [Indexed: 11/08/2022] Open
Abstract
Mass thermal bleaching events are a primary threat to coral reefs, yet the sublethal impacts, particularly on energetics and reproduction, are poorly characterized. Given that the persistence of coral populations is contingent upon the reproduction of individuals that survive disturbances, there is an urgent need to understand the sublethal effects of bleaching on reproductive output to accurately predict coral recovery rates. In 2019, the French Polynesian island of Mo'orea experienced a severe mass bleaching event accompanied by widespread coral mortality. At the most heavily impacted sites, we observed Acropora hyacinthus individuals that were resistant to bleaching, alongside colonies that bleached but showed signs of symbiont recovery shortly after the bleaching event. We collected fragments from A. hyacinthus colonies five months post-bleaching and, using energetic assays and histological measurements, examined the physiological and reproductive consequences of these two distinct heat stress responses. Despite healthy appearances in both resistant and recovered corals, we found that recovered colonies had significantly reduced energy reserves compared to resistant colonies. In addition, we detected compound effects of stress on reproduction: recovered colonies displayed both a lower probability of containing gametes and lower fecundity per polyp. Our results indicate that bleaching inflicts an energetic constraint on the concurrent re-accumulation of energy reserves and development of reproductive material, with decreased reproductive potential of survivors possibly hampering overall reef resilience. These findings highlight the presence of intraspecific responses to bleaching and the importance of considering multiple trajectories for individual species when predicting population recovery following disturbance.
Collapse
Affiliation(s)
- Sarah E Leinbach
- Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA.
| | - Kelly E Speare
- Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA, 93117, USA
| | - Ashley M Rossin
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Daniel M Holstein
- Department of Oceanography and Coastal Sciences, Louisiana State University, Baton Rouge, LA, 70803, USA
| | - Marie E Strader
- Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA
| |
Collapse
|
12
|
Innis T, Allen-Waller L, Brown KT, Sparagon W, Carlson C, Kruse E, Huffmyer AS, Nelson CE, Putnam HM, Barott KL. Marine heatwaves depress metabolic activity and impair cellular acid-base homeostasis in reef-building corals regardless of bleaching susceptibility. GLOBAL CHANGE BIOLOGY 2021; 27:2728-2743. [PMID: 33784420 DOI: 10.1111/gcb.15622] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/18/2021] [Accepted: 03/21/2021] [Indexed: 06/12/2023]
Abstract
Ocean warming is causing global coral bleaching events to increase in frequency, resulting in widespread coral mortality and disrupting the function of coral reef ecosystems. However, even during mass bleaching events, many corals resist bleaching despite exposure to abnormally high temperatures. While the physiological effects of bleaching have been well documented, the consequences of heat stress for bleaching-resistant individuals are not well understood. In addition, much remains to be learned about how heat stress affects cellular-level processes that may be overlooked at the organismal level, yet are crucial for coral performance in the short term and ecological success over the long term. Here we compared the physiological and cellular responses of bleaching-resistant and bleaching-susceptible corals throughout the 2019 marine heatwave in Hawai'i, a repeat bleaching event that occurred 4 years after the previous regional event. Relative bleaching susceptibility within species was consistent between the two bleaching events, yet corals of both resistant and susceptible phenotypes exhibited pronounced metabolic depression during the heatwave. At the cellular level, bleaching-susceptible corals had lower intracellular pH than bleaching-resistant corals at the peak of bleaching for both symbiont-hosting and symbiont-free cells, indicating greater disruption of acid-base homeostasis in bleaching-susceptible individuals. Notably, cells from both phenotypes were unable to compensate for experimentally induced cellular acidosis, indicating that acid-base regulation was significantly impaired at the cellular level even in bleaching-resistant corals and in cells containing symbionts. Thermal disturbances may thus have substantial ecological consequences, as even small reallocations in energy budgets to maintain homeostasis during stress can negatively affect fitness. These results suggest concern is warranted for corals coping with ocean acidification alongside ocean warming, as the feedback between temperature stress and acid-base regulation may further exacerbate the physiological effects of climate change.
Collapse
Affiliation(s)
- Teegan Innis
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Kristen T Brown
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
- ARC Centre of Excellence for Coral Reef Studies and School of Biological Sciences, University of Queensland, St. Lucia, Qld, Australia
| | - Wesley Sparagon
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, Department of Oceanography and Sea Grant College Program, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | | | - Elisa Kruse
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Ariana S Huffmyer
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, USA
| | - Craig E Nelson
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education, Department of Oceanography and Sea Grant College Program, University of Hawai'i at Mānoa, Honolulu, HI, USA
| | - Hollie M Putnam
- Department of Biological Sciences, University of Rhode Island, Kingston, RI, USA
| | - Katie L Barott
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
13
|
Coral bleaching response is unaltered following acclimatization to reefs with distinct environmental conditions. Proc Natl Acad Sci U S A 2021; 118:2025435118. [PMID: 34050025 PMCID: PMC8179235 DOI: 10.1073/pnas.2025435118] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Ocean warming has caused catastrophic losses of corals on reefs worldwide and is intensifying faster than the adaptive rate of most coral populations that remain. Human interventions, such as propagation of heat-resistant corals, may help maintain reef function and delay further devastation of these valuable ecosystems as society confronts the climate crisis. However, exposing adult corals to a complex suite of new environmental conditions could lead to tradeoffs that alter their heat stress responses, and empirical data are needed to test the utility of this approach. Here, we show that corals transplanted to novel reef conditions did not exhibit changes in their heat stress response or negative fitness tradeoffs, supporting the inclusion of this approach in our management arsenal. Urgent action is needed to prevent the demise of coral reefs as the climate crisis leads to an increasingly warmer and more acidic ocean. Propagating climate change–resistant corals to restore degraded reefs is one promising strategy; however, empirical evidence is needed to determine whether stress resistance is affected by transplantation beyond a coral’s native reef. Here, we assessed the performance of bleaching-resistant individuals of two coral species following reciprocal transplantation between reefs with distinct pH, salinity, dissolved oxygen, sedimentation, and flow dynamics to determine whether heat stress response is altered following coral exposure to novel physicochemical conditions in situ. Critically, transplantation had no influence on coral heat stress responses, indicating that this trait was relatively fixed. In contrast, growth was highly plastic, and native performance was not predictive of performance in the novel environment. Coral metabolic rates and overall fitness were higher at the reef with higher flow, salinity, sedimentation, and diel fluctuations of pH and dissolved oxygen, and did not differ between native and cross-transplanted corals, indicating acclimatization via plasticity within just 3 mo. Conversely, cross-transplants at the second reef had higher fitness than native corals, thus increasing the fitness potential of the recipient population. This experiment was conducted during a nonbleaching year, so the potential benefits to recipient population fitness are likely enhanced during bleaching years. In summary, this study demonstrates that outplanting bleaching-resistant corals is a promising tool for elevating the resistance of coral populations to ocean warming.
Collapse
|
14
|
McRae CJ, Huang WB, Fan TY, Côté IM. Effects of thermal conditioning on the performance of Pocillopora acuta adult coral colonies and their offspring. CORAL REEFS (ONLINE) 2021; 40:1491-1503. [PMID: 34720373 PMCID: PMC8550305 DOI: 10.1007/s00338-021-02123-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Accepted: 05/25/2021] [Indexed: 05/02/2023]
Abstract
UNLABELLED Ocean warming induced by climate change is the greatest threat to the persistence of coral reefs globally. Given the current rate of ocean warming, there may not be sufficient time for natural acclimation or adaptation by corals. This urgency has led to the exploration of active management techniques aimed at enhancing thermal tolerance in corals. Here, we test the capacity for transgenerational acclimation in the reef-building coral Pocillopora acuta as a means of increasing offspring performance in warmer waters. We exposed coral colonies from a reef influenced by intermittent upwelling and constant warm-water effluent from a nuclear power plant to temperatures that matched (26 °C) or exceeded (29.5 °C) season-specific mean temperatures for three reproductive cycles; offspring were allowed to settle and grow at both temperatures. Heated colonies reproduced significantly earlier in the lunar cycle and produced fewer and smaller planulae. Recruitment was lower at the heated recruitment temperature regardless of parent treatment. Recruit survival did not differ based on parent or recruitment temperature. Recruits from heated parents were smaller and had lower maximum quantum yield (Fv/Fm), a measurement of symbiont photochemical performance. We found no direct evidence that thermal conditioning of adult P. acuta corals improves offspring performance in warmer water; however, chronic exposure of parent colonies to warmer temperatures at the source reef site may have limited transgenerational acclimation capacity. The extent to which coral response to this active management approach might vary across species and sites remains unclear and merits further investigation. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00338-021-02123-9.
Collapse
Affiliation(s)
- Crystal J. McRae
- Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien, Taiwan
- Department of Biological Sciences, Simon Fraser University, British Columbia, Canada
| | - Wen-Bin Huang
- Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien, Taiwan
| | - Tung-Yung Fan
- Institute of Marine Biology, National Dong Hwa University, Pingtung, Taiwan
- National Museum of Marine Biology and Aquarium, Pingtung, Taiwan
| | - Isabelle M. Côté
- Department of Biological Sciences, Simon Fraser University, British Columbia, Canada
| |
Collapse
|
15
|
Johnston EC, Counsell CWW, Sale TL, Burgess SC, Toonen RJ. The legacy of stress: Coral bleaching impacts reproduction years later. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13653] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Erika C. Johnston
- School of Ocean and Earth Science Technology Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at Mānoa Kāne‘ohe HI USA
- Department of Biological Science Florida State University Tallahassee FL USA
| | - Chelsie W. W. Counsell
- School of Ocean and Earth Science Technology Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at Mānoa Kāne‘ohe HI USA
| | - Tayler L. Sale
- Department of Biology University of Hawai‘i at Mānoa Honolulu HI USA
| | - Scott C. Burgess
- Department of Biological Science Florida State University Tallahassee FL USA
| | - Robert J. Toonen
- School of Ocean and Earth Science Technology Hawai‘i Institute of Marine BiologyUniversity of Hawai‘i at Mānoa Kāne‘ohe HI USA
| |
Collapse
|
16
|
Howells EJ, Bauman AG, Vaughan GO, Hume BCC, Voolstra CR, Burt JA. Corals in the hottest reefs in the world exhibit symbiont fidelity not flexibility. Mol Ecol 2020; 29:899-911. [DOI: 10.1111/mec.15372] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/17/2020] [Accepted: 01/29/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Emily J. Howells
- Center for Genomics and Systems Biology New York University Abu Dhabi Abu Dhabi United Arab Emirates
- Centre for Sustainable Ecosystem Solutions and School of Earth, Atmospheric and Life Sciences University of Wollongong Wollongong NSW Australia
| | - Andrew G. Bauman
- Experimental Marine Ecology Laboratory Department of Biological Sciences National University of Singapore Singapore City Singapore
| | - Grace O. Vaughan
- Center for Genomics and Systems Biology New York University Abu Dhabi Abu Dhabi United Arab Emirates
| | - Benjamin C. C. Hume
- Red Sea Research Center Division of Biological and Environmental Sciences and Engineering King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
| | - Christian R. Voolstra
- Red Sea Research Center Division of Biological and Environmental Sciences and Engineering King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia
- Department of Biology University of Konstanz Konstanz Germany
| | - John A. Burt
- Center for Genomics and Systems Biology New York University Abu Dhabi Abu Dhabi United Arab Emirates
| |
Collapse
|
17
|
Monteil Y, Teo A, Fong J, Bauman AG, Todd PA. Effects of macroalgae on coral fecundity in a degraded coral reef system. MARINE POLLUTION BULLETIN 2020; 151:110890. [PMID: 32056657 DOI: 10.1016/j.marpolbul.2020.110890] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 12/17/2019] [Accepted: 01/06/2020] [Indexed: 06/10/2023]
Abstract
Global declines in live coral cover and the proliferation of macroalgae on coral reefs is leading to increased coral-macroalgal interactions that impact reef recovery. However, the effects of macroalgae on coral sexual reproduction-a fundamental life-history process for maintaining population abundances-have rarely been quantified. Here, we examined the direct effects of macroalgae contact on the fecundity (eggs mesentery-1) of two coral species, Echinopora lamellosa and Merulina ampliata, across three degraded reefs in Singapore. Increasing macroalgae contact from 5% to 25% significantly reduced fecundity in colonies of both species by 67-82%, and also reduced M. ampliata egg sizes by 11.4%. These results suggest the diversion of energy from reproduction towards other processes such as repair and defence, and also reveal potential differential energy allocation strategies among coral taxa. While corals on Singapore's impacted reefs continue to produce eggs, increasing macroalgae that suppresses coral fecundity may constrain future reef recovery.
Collapse
Affiliation(s)
- Yann Monteil
- Université de La Rochelle, Pôle Sciences, Laboratoire de Biologie et d'Environnement Marins, FRE2727, Avenue Michel Crépeau, 17042 La Rochelle, Cedex, France
| | - Aaron Teo
- Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore
| | - Jenny Fong
- Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore
| | - Andrew G Bauman
- Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore.
| | - Peter A Todd
- Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore
| |
Collapse
|
18
|
Riegl B, Johnston M, Purkis S, Howells E, Burt J, Steiner SCC, Sheppard CRC, Bauman A. Population collapse dynamics in Acropora downingi, an Arabian/Persian Gulf ecosystem-engineering coral, linked to rising temperature. GLOBAL CHANGE BIOLOGY 2018; 24:2447-2462. [PMID: 29504709 DOI: 10.1111/gcb.14114] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 06/08/2023]
Abstract
As in the tropical Atlantic, Acropora populations in the southern Persian/Arabian Gulf plummeted within two decades after having been ecosystem engineers on most wave-exposed reefs since the Pleistocene. Since 1996/1998 live coral cover in the Gulf declined by over 90% in many areas, primarily due to bleaching and diseases caused by rising temperatures. In the formerly dominant table-coral species A. downingi, population dynamics corresponding to disturbance regimes was quantified in three transition matrices (lower disturbance pre-1996; moderate disturbance from 1998 to 2010 and 2013 to 2017, disturbed in 1996/1998, 2010/11/12, 2017). Increased disturbance frequency and severity caused progressive reduction in coral size, cover, and population fecundity. Small size-classes were bolstered more by partial colony mortality than sexual recruitment. Some large corals had a size refuge and resisted die-back but were also lost with increasing disturbance. Matrix and biophysical larval flow models suggested one metapopulation. Southern, Arabian, populations could be connected to northern, Iranian, populations but this connectivity was lost under assumptions of pelagic larval duration at rising temperatures shortened to a third. Then, the metapopulation disintegrated into isolated populations. Connectivity required to avoid extinctions increased exponentially with disturbance frequency and correlation of disturbances across the metapopulation. Populations became unsustainable at eight disturbances in 15 years, when even highest theoretical recruitment no longer compensated mortality. This lethal disturbance frequency was 3-fold that of the moderately disturbed monitoring period and 4-fold of the preceding low-disturbance period-suggesting ongoing shortening of the disturbance-free period. Observed population collapse and environmental changes in the Gulf suggest that A. downingi is heading toward at least functional extinction mainly due to increasingly frequent temperature-induced mortality events, clearly linked to climate change.
Collapse
Affiliation(s)
- Bernhard Riegl
- Department of Marine and Environmental Sciences, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, FL, USA
| | - Matthew Johnston
- Department of Biology, Halmos College of Natural Sciences and Oceanography, Nova Southeastern University, Dania Beach, FL, USA
| | - Sam Purkis
- Department of Marine Geology and Geophysics, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL, USA
| | - Emily Howells
- Center for Genomics and Systems Biology, New York University at Abu Dhabi, Abu Dhabi, UAE
| | - John Burt
- Center for Genomics and Systems Biology, New York University at Abu Dhabi, Abu Dhabi, UAE
| | | | | | - Andrew Bauman
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| |
Collapse
|
19
|
McMahon KM, Evans RD, van Dijk KJ, Hernawan U, Kendrick GA, Lavery PS, Lowe R, Puotinen M, Waycott M. Disturbance Is an Important Driver of Clonal Richness in Tropical Seagrasses. FRONTIERS IN PLANT SCIENCE 2017; 8:2026. [PMID: 29259609 PMCID: PMC5723400 DOI: 10.3389/fpls.2017.02026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 11/14/2017] [Indexed: 05/26/2023]
Abstract
Clonality is common in many aquatic plant species, including seagrasses, where populations are maintained through a combination of asexual and sexual reproduction. One common measure used to describe the clonal structure of populations is clonal richness. Clonal richness is strongly dependent on the biological characteristics of the species, and how these interact with the environment but can also reflect evolutionary scale processes especially at the edge of species ranges. However, little is known about the spatial patterns and drivers of clonal richness in tropical seagrasses. This study assessed the spatial patterns of clonal richness in meadows of three tropical seagrass species, Thalassia hemprichii, Halodule uninervis, and Halophila ovalis, spanning a range of life-history strategies and spatial scales (2.5-4,711 km) in Indonesia and NW Australia. We further investigated the drivers of clonal richness using general additive mixed models for two of the species, H. uninervis and H. ovalis, over 8° latitude. No significant patterns were observed in clonal richness with latitude, yet disturbance combined with sea surface temperature strongly predicted spatial patterns of clonal richness. Sites with a high probability of cyclone disturbance had low clonal richness, whereas an intermediate probability of cyclone disturbance and the presence of dugong grazing combined with higher sea surface temperatures resulted in higher levels of clonal richness. We propose potential mechanisms for these patterns related to the recruitment and mortality rates of individuals as well as reproductive effort. Under a changing climate, increased severity of tropical cyclones and the decline in populations of mega-grazers have the potential to reduce clonal richness leading to less genetically diverse populations.
Collapse
Affiliation(s)
- Kathryn M. McMahon
- School of Science and Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
- Western Australian Marine Science Institution, Crawley, WA, Australia
| | - Richard D. Evans
- Marine Science Program, Science and Conservation Division, Department of Biodiversity, Conservation and Attractions, Kensington, WA, Australia
- School of Biological Sciences, University of Western Australia, Crawley, WA, Australia
- UWA Oceans Institute, Crawley, WA, Australia
| | - Kor-jent van Dijk
- School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Udhi Hernawan
- School of Science and Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
- Pusat Penelitian Oseanografi - Lembaga Ilmu Pengetahuan Indonesia, Jakarta, Indonesia
| | - Gary A. Kendrick
- School of Biological Sciences, University of Western Australia, Crawley, WA, Australia
- UWA Oceans Institute, Crawley, WA, Australia
| | - Paul S. Lavery
- School of Science and Centre for Marine Ecosystems Research, Edith Cowan University, Joondalup, WA, Australia
- Western Australian Marine Science Institution, Crawley, WA, Australia
- Centro de Estudios Avanzados de Blanes, Consejo Superior de Investigaciones Cientificas, Blanes, Spain
| | - Ryan Lowe
- UWA Oceans Institute, Crawley, WA, Australia
- School of Earth Sciences, University of Western Australia, Crawley, WA, Australia
| | - Marji Puotinen
- Indian Ocean Marine Research Centre, Australian Institute of Marine Science, University of Western Australia, Crawley, WA, Australia
| | - Michelle Waycott
- School of Biological Sciences, University of Adelaide, Adelaide, SA, Australia
- State Herbarium of South Australia, Department of Environment, Water and Natural Resources, Adelaide, SA, Australia
| |
Collapse
|
20
|
Pratchett MS, Baird AH, Bauman AG, Burt JA. Abundance and composition of juvenile corals reveals divergent trajectories for coral assemblages across the United Arab Emirates. MARINE POLLUTION BULLETIN 2017; 114:1031-1035. [PMID: 27889075 DOI: 10.1016/j.marpolbul.2016.11.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 11/15/2016] [Accepted: 11/16/2016] [Indexed: 06/06/2023]
Abstract
Marked shifts in the composition of coral assemblages are occurring at many locations, but it is unknown whether these are permanent shifts reinforced by patterns of population replenishment. This study examined the composition of juvenile coral assemblages across the United Arab Emirates (UAE). Densities of juvenile corals varied significantly among locations, but were highest where coral cover was highest. Juvenile coral assemblages within the Persian Gulf were dominated by Porites, while no Acropora were recorded. We expect therefore, continued declines in Acropora abundance, while observed dominance of Porites is likely to persist. In the Oman Sea, Pocillopora was the dominant juvenile coral, with Acropora and Stylophora also recorded. This study shows that taxonomic differences in replenishment are reinforcing temporal shifts in coral composition within the southern Persian Gulf, but not in the Oman Sea. Differences in environmental conditions and disturbance regimes likely explain the divergent responses between regions.
Collapse
Affiliation(s)
- Morgan S Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville Q4811, Australia
| | - Andrew H Baird
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville Q4811, Australia
| | - Andrew G Bauman
- Experimental Marine Ecology Laboratory, Department of Biological Sciences, National University of Singapore, 117543, Singapore
| | - John A Burt
- Center for Genomics and Systems Biology, New York University, Abu Dhabi, PO Box 129188, Abu Dhabi, United Arab Emirates.
| |
Collapse
|
21
|
Howells EJ, Abrego D, Meyer E, Kirk NL, Burt JA. Host adaptation and unexpected symbiont partners enable reef-building corals to tolerate extreme temperatures. GLOBAL CHANGE BIOLOGY 2016; 22:2702-14. [PMID: 26864257 DOI: 10.1111/gcb.13250] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 02/02/2016] [Accepted: 02/02/2016] [Indexed: 05/18/2023]
Abstract
Understanding the potential for coral adaptation to warming seas is complicated by interactions between symbiotic partners that define stress responses and the difficulties of tracking selection in natural populations. To overcome these challenges, we characterized the contribution of both animal host and symbiotic algae to thermal tolerance in corals that have already experienced considerable warming on par with end-of-century projections for most coral reefs. Thermal responses in Platygyra daedalea corals from the hot Persian Gulf where summer temperatures reach 36°C were compared with conspecifics from the milder Sea of Oman. Persian Gulf corals had higher rates of survival at elevated temperatures (33 and 36°C) in both the nonsymbiotic larval stage (32-49% higher) and the symbiotic adult life stage (51% higher). Additionally, Persian Gulf hosts had fixed greater potential to mitigate oxidative stress (31-49% higher) and their Symbiodinium partners had better retention of photosynthetic performance under elevated temperature (up to 161% higher). Superior thermal tolerance of Persian Gulf vs. Sea of Oman corals was maintained after 6-month acclimatization to a common ambient environment and was underpinned by genetic divergence in both the coral host and symbiotic algae. In P. daedalea host samples, genomewide SNP variation clustered into two discrete groups corresponding with Persian Gulf and Sea of Oman sites. Symbiodinium within host tissues predominantly belonged to ITS2 rDNA type C3 in the Persian Gulf and type D1a in the Sea of Oman contradicting patterns of Symbiodinium thermal tolerance from other regions. Our findings provide evidence that genetic adaptation of both host and Symbiodinium has enabled corals to cope with extreme temperatures in the Persian Gulf. Thus, the persistence of coral populations under continued warming will likely be determined by evolutionary rates in both, rather than single, symbiotic partners.
Collapse
Affiliation(s)
- Emily J Howells
- Center for Genomics and Systems Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
| | - David Abrego
- Department of Natural Science and Public Health, Zayed University, P.O. Box 144534, Abu Dhabi, United Arab Emirates
| | - Eli Meyer
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
| | - Nathan L Kirk
- Department of Integrative Biology, Oregon State University, 3029 Cordley Hall, Corvallis, OR 97331, USA
| | - John A Burt
- Center for Genomics and Systems Biology, New York University Abu Dhabi, P.O. Box 129188, Abu Dhabi, United Arab Emirates
| |
Collapse
|
22
|
Bento R, Hoey AS, Bauman AG, Feary DA, Burt JA. The implications of recurrent disturbances within the world's hottest coral reef. MARINE POLLUTION BULLETIN 2016; 105:466-472. [PMID: 26478453 DOI: 10.1016/j.marpolbul.2015.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/25/2015] [Accepted: 10/06/2015] [Indexed: 06/05/2023]
Abstract
Determining how coral ecosystems are structured within extreme environments may provide insights into how coral reefs are impacted by future climate change. Benthic community structure was examined within the Persian Gulf, and adjacent Musandam and northern Oman regions across a 3-year period (2008-2011) in which all regions were exposed to major disturbances. Although there was evidence of temporal switching in coral composition within regions, communities predominantly reflected local environmental conditions and the disturbance history of each region. Gulf reefs showed little change in coral composition, being dominated by stress-tolerant Faviidae and Poritidae across the 3 years. In comparison, Musandam and Oman coral communities were comprised of stress-sensitive Acroporidae and Pocilloporidae; Oman communities showed substantial declines in such taxa and increased cover of stress-tolerant communities. Our results suggest that coral communities may persist within an increasingly disturbed future environment, albeit in a much more structurally simple configuration.
Collapse
Affiliation(s)
- Rita Bento
- ICBAS, Porto University, Rua de Jorge Viterbo Ferreira no. 228, 4050-313 Porto, Portugal; Emirates Diving Association, PO Box 33220 Dubai, United Arab Emirates
| | - Andrew S Hoey
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville Q4811, Australia.
| | - Andrew G Bauman
- Experimental Marine Ecology Laboratory, Department of Biological Science, National University of Singapore, 117543 Singapore
| | - David A Feary
- School of Life Sciences, University of Nottingham, NG7 2RD, United Kingdom
| | - John A Burt
- Center for Genomics and Systems Biology, New York University Abu Dhabi, PO Box 129188, Abu Dhabi, United Arab Emirates
| |
Collapse
|
23
|
Shuail D, Wiedenmann J, D'Angelo C, Baird AH, Pratchett MS, Riegl B, Burt JA, Petrov P, Amos C. Local bleaching thresholds established by remote sensing techniques vary among reefs with deviating bleaching patterns during the 2012 event in the Arabian/Persian Gulf. MARINE POLLUTION BULLETIN 2016; 105:654-659. [PMID: 26971815 DOI: 10.1016/j.marpolbul.2016.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/06/2016] [Accepted: 03/01/2016] [Indexed: 06/05/2023]
Abstract
A severe bleaching event affected coral communities off the coast of Abu Dhabi, UAE in August/September, 2012. In Saadiyat and Ras Ghanada reefs ~40% of the corals showed signs of bleaching. In contrast, only 15% of the corals were affected on Delma reef. Bleaching threshold temperatures for these sites were established using remotely sensed sea surface temperature (SST) data recorded by MODIS-Aqua. The calculated threshold temperatures varied between locations (34.48 °C, 34.55 °C, 35.05 °C), resulting in site-specific deviations in the numbers of days during which these thresholds were exceeded. Hence, the less severe bleaching of Delma reef might be explained by the lower relative heat stress experienced by this coral community. However, the dominance of Porites spp. that is associated with the long-term exposure of Delma reef to elevated temperatures, as well as the more pristine setting may have additionally contributed to the higher coral bleaching threshold for this site.
Collapse
Affiliation(s)
- Dawood Shuail
- Coral Reef Laboratory, Ocean and Earth Science, University of Southampton, SO143ZH Southampton, UK
| | - Jörg Wiedenmann
- Coral Reef Laboratory, Ocean and Earth Science, University of Southampton, SO143ZH Southampton, UK
| | - Cecilia D'Angelo
- Coral Reef Laboratory, Ocean and Earth Science, University of Southampton, SO143ZH Southampton, UK
| | - Andrew H Baird
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia
| | - Morgan S Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland 4811, Australia
| | - Bernhard Riegl
- National Coral Reef Institute, Nova Southeastern University, Fort Lauderdale, Florida 33314-7796, USA
| | - John A Burt
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Peter Petrov
- Regional Organization for the Protection of the Marine Environment (ROPME), 13124 Safat, Kuwait
| | - Carl Amos
- Coral Reef Laboratory, Ocean and Earth Science, University of Southampton, SO143ZH Southampton, UK
| |
Collapse
|