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Foo SA, Millican HR, Byrne M. Crown-of-thorns seastar (Acanthaster spp.) feeding ecology across species and regions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 930:172691. [PMID: 38663591 DOI: 10.1016/j.scitotenv.2024.172691] [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: 01/24/2024] [Revised: 04/09/2024] [Accepted: 04/20/2024] [Indexed: 05/03/2024]
Abstract
The coral predators, crown-of-thorns starfish (COTS, Acanthaster spp.) remain a major cause of extensive and widespread coral loss in Indo-Pacific coral reefs. With increased phylogenetic understanding of these seastars, at least five species appear to be present across different regions. We compare the feeding ecology of these species. Where acroporid corals are prevalent, Acanthaster spp. often exhibit a preference for these corals, with Porites being least preferred, as seen in most species including Acanthaster planci in the northern Indian Ocean and Acanthaster cf. solaris in the west Pacific. In the eastern Pacific, where Acropora is largely absent, Acanthaster cf. ellisii prey on a range of coral species, including Porites. Coral predation by COTS is influenced by several factors including food availability, coral nutritional value, protective crustaceans and coral defenses, with differences in feeding ecology and behaviour emerging across the different COTS species. Feeding behaviour of COTS can act to increase coral species richness by reducing the dominance of fast-growing species. In outbreaking populations, COTS impacts reef systems by reducing live coral cover, eroding reef complexity and causing shifts in reef trophic structure. Where data are available, we synthesise and contrast the feeding preferences and foraging behaviour of Acanthaster species, and their impact on coral assemblages across the different species and regions. For areas where focal predation on Acropora occurs, also the fastest growing coral with the greatest recovery potential following mass mortality events, the combination of climate change and COTS outbreaks presents an imminent threat to coral reefs. This is exacerbated by the dietary flexibility of Acanthaster species. The impacts of heatwaves, COTS and other stressors are creating a negative feedback loop accelerating coral reef decline.
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Affiliation(s)
- Shawna A Foo
- School of Life and Environmental Sciences, the University of Sydney, NSW 2006, Australia.
| | - Hayden R Millican
- School of Life and Environmental Sciences, the University of Sydney, NSW 2006, Australia
| | - Maria Byrne
- School of Life and Environmental Sciences, the University of Sydney, NSW 2006, Australia
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2
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Morin M, Jönsson M, Wang CK, Craik DJ, Degnan SM, Degnan BM. Seasonal tissue-specific gene expression in wild crown-of-thorns starfish reveals reproductive and stress-related transcriptional systems. PLoS Biol 2024; 22:e3002620. [PMID: 38743647 PMCID: PMC11093393 DOI: 10.1371/journal.pbio.3002620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 04/10/2024] [Indexed: 05/16/2024] Open
Abstract
Animals are influenced by the season, yet we know little about the changes that occur in most species throughout the year. This is particularly true in tropical marine animals that experience relatively small annual temperature and daylight changes. Like many coral reef inhabitants, the crown-of-thorns starfish (COTS), well known as a notorious consumer of corals and destroyer of coral reefs, reproduces exclusively in the summer. By comparing gene expression in 7 somatic tissues procured from wild COTS sampled on the Great Barrier Reef, we identified more than 2,000 protein-coding genes that change significantly between summer and winter. COTS genes that appear to mediate conspecific communication, including both signalling factors released into the surrounding sea water and cell surface receptors, are up-regulated in external secretory and sensory tissues in the summer, often in a sex-specific manner. Sexually dimorphic gene expression appears to be underpinned by sex- and season-specific transcription factors (TFs) and gene regulatory programs. There are over 100 TFs that are seasonally expressed, 87% of which are significantly up-regulated in the summer. Six nuclear receptors are up-regulated in all tissues in the summer, suggesting that systemic seasonal changes are hormonally controlled, as in vertebrates. Unexpectedly, there is a suite of stress-related chaperone proteins and TFs, including HIFa, ATF3, C/EBP, CREB, and NF-κB, that are uniquely and widely co-expressed in gravid females. The up-regulation of these stress proteins in the summer suggests the demands of oogenesis in this highly fecund starfish affects protein stability and turnover in somatic cells. Together, these circannual changes in gene expression provide novel insights into seasonal changes in this coral reef pest and have the potential to identify vulnerabilities for targeted biocontrol.
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Affiliation(s)
- Marie Morin
- Centre for Marine Science, School of the Environment, The University of Queensland, Brisbane, Australia
| | - Mathias Jönsson
- Centre for Marine Science, School of the Environment, The University of Queensland, Brisbane, Australia
| | - Conan K. Wang
- Institute for Molecular Bioscience, ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Australia
| | - David J. Craik
- Institute for Molecular Bioscience, ARC Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Australia
| | - Sandie M. Degnan
- Centre for Marine Science, School of the Environment, The University of Queensland, Brisbane, Australia
| | - Bernard M. Degnan
- Centre for Marine Science, School of the Environment, The University of Queensland, Brisbane, Australia
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3
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Mos B, Mesic N, Dworjanyn SA. Variable food alters responses of larval crown-of-thorns starfish to ocean warming but not acidification. Commun Biol 2023; 6:639. [PMID: 37316528 DOI: 10.1038/s42003-023-05028-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 06/08/2023] [Indexed: 06/16/2023] Open
Abstract
Phytoplankton abundance is decreasing and becoming more variable as the ocean climate changes. We examine how low, high, and variable phytoplankton food supply affected the survival, development, and growth of larval crown-of-thorns starfish, Acanthaster sp. exposed to combined warming (26, 30 °C) and acidification (pH 8.0, 7.6). Larvae fed a low food ration are smaller, and develop slower and with more abnormalities than larvae fed a high ration. Larvae fed a variable food supply (low, followed by high ration) overcome the negative effects of low food on development rate and occurrence of abnormalities, but are 16-17% smaller than larvae fed the high ration continuously. Acidification (pH 7.6) slows growth and development and increases abnormalities regardless of the food regime. Warming slows growth and development, but these effects are mitigated by high food availability. As tropical oceans warm, the success of crown-of-thorns starfish larvae may depend on the abundance of their phytoplankton prey.
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Affiliation(s)
- Benjamin Mos
- Moreton Bay Research Station (MBRS), School of Biological Sciences, The University of Queensland, 37 Fraser Street, Dunwich, Minjerribah, QLD 4183, Australia.
- Centre for Marine Science (CMS), The University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Naomi Mesic
- National Marine Science Centre, Faculty of Science and Engineering, Southern Cross University, PO Box 4321, Coffs Harbour, NSW, 2450, Australia
| | - Symon A Dworjanyn
- National Marine Science Centre, Faculty of Science and Engineering, Southern Cross University, PO Box 4321, Coffs Harbour, NSW, 2450, Australia
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Wang L, Xu J, Liu H, Wang S, Ou W, Zhang M, Wei F, Luo S, Chen B, Zhang S, Yu K. Ultrasensitive and on-site eDNA detection for the monitoring of crown-of-thorns starfish densities at the pre-outbreak stage using an electrochemical biosensor. Biosens Bioelectron 2023; 230:115265. [PMID: 36996547 DOI: 10.1016/j.bios.2023.115265] [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: 12/16/2022] [Revised: 03/02/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023]
Abstract
The coral reef crisis has significantly intensified over the last decades, mainly due to severe outbreaks of crown-of-thorns starfish (COTS). Current ecological monitoring has failed to detect COTS densities at the pre-outbreak stage, thus preventing early intervention. In this work, we developed an effective electrochemical biosensor modified by a MoO2/C nanomaterial, as well as a specific DNA probe that could detect trace COTS environmental DNA (eDNA) at a lower detection limit (LOD = 0.147 ng/μL) with excellent specificity. The reliability and accuracy of the biosensor were validated against the standard methods by an ultramicro spectrophotometer and droplet digital PCR (p > 0.05). The biosensor was then utilized for the on-site analysis of seawater samples from SYM-LD and SY sites in the South China Sea. For the SYM-LD site suffering an outbreak, the COTS eDNA concentrations were 0.33 ng/μL (1 m, depth) and 0.26 ng/μL (10 m, depth), respectively. According to the ecological survey, the COTS density was 500 ind/hm2 at the SYM-LD site, verifying the accuracy of our measurements. At the SY site, COTS eDNA was also detected at 0.19 ng/μL, but COTS was not found by the traditional survey. Hence, larvae were possibly present in this region. Therefore, this electrochemical biosensor could be used to monitor COTS populations at the pre-outbreak stages, and potentially serve as a revolutionary early warning method. We will continue to improve this method for picomolar or even femtomolar detection of COTS eDNA.
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Affiliation(s)
- Liwei Wang
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China; School of Resources, Environment and Materials, Guangxi, Key Laboratory of Processing for Non-ferrous Metallic and Featured Materials, Nanning, 530003, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China
| | - Jiarong Xu
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China; School of Resources, Environment and Materials, Guangxi, Key Laboratory of Processing for Non-ferrous Metallic and Featured Materials, Nanning, 530003, China
| | - Hongjie Liu
- School of Resources, Environment and Materials, Guangxi, Key Laboratory of Processing for Non-ferrous Metallic and Featured Materials, Nanning, 530003, China; School of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, China; College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Shaopeng Wang
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Wenchao Ou
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Man Zhang
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Fen Wei
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Songlin Luo
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Biao Chen
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China
| | - Shaolong Zhang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, 518060, China
| | - Kefu Yu
- School of Marine Sciences, Coral Reef Research Center of China, Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Guangxi University, Nanning, 530004, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, 519080, China.
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Mendoza-Porras O, Nguyen TV, Shah RM, Thomas-Hall P, Bastin L, Deaker DJ, Motti CA, Byrne M, Beale DJ. Biochemical metabolomic profiling of the Crown-of-Thorns Starfish (Acanthaster): New insight into its biology for improved pest management. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 861:160525. [PMID: 36574554 DOI: 10.1016/j.scitotenv.2022.160525] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 11/20/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
The Crown-of-Thorns Starfish (COTS), Acanthaster species, is a voracious coral predator that destroys coral reefs when in outbreak status. The baseline metabolite and lipid biomolecules of 10 COTS tissues, including eggs from gravid females, were investigated in this study to provide insight into their biology and identify avenues for control. Targeted and untargeted metabolite- and lipidomics-based mass spectrometry approaches were used to obtain tissue-specific metabolite and lipid profiles. Across all COTS tissues, 410 metabolites and 367 lipids were identified. Most abundant were amino acids and peptides (18.7%) and wax esters (17%). There were 262 metabolites and 192 lipids identified in COTS eggs. Wax esters were more abundant in the eggs (30%) followed by triacylglycerols (TG), amino acids, and peptides. The diversity of asterosaponins in eggs (34) was higher than in tissues (2). Several asterosaponins known to modulate sperm acrosome reaction were putatively identified, including glycoside B, asterosaponin-4 (Co-Aris III), and regularoside B (asterosaponin A). The saponins saponin A, thornasteroside A, hillaside B, and non-saponins dictyol J and axinellamine B which have been shown to possess defensive properties, were found in abundance in gonads, skin, and radial nerve tissues. Inosine and 2-hexyldecanoic acid are the most abundant metabolites in tissues and eggs. As a secondary metabolite of purine degradation, inosine plays an important role in purine biosynthesis, while 2-hexyldecanoic acid is known to suppress side-chain crystallization during the synthesis of amphiphilic macromolecules (i.e., phospholipids). These significant spatial changes in metabolite, lipid, and asterosaponin profiles enabled unique insights into key biological tissue-specific processes that could be manipulated to better control COTS populations. Our findings highlight COTS as a novel source of molecules with therapeutic and cosmetic properties (ceramides, sphingolipids, carnosine, and inosine). These outcomes will be highly relevant for the development of strategies for COTS management including chemotaxis-based biocontrol and exploitation of COTS carcasses for the extraction of commercial molecules.
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Affiliation(s)
- Omar Mendoza-Porras
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Queensland Bioscience Precinct, St Lucia, QLD 4067, Australia
| | - Thao V Nguyen
- Land and Water, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Ecosciences Precinct, Dutton Park, QLD 4102, Australia
| | - Rohan M Shah
- Land and Water, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Ecosciences Precinct, Dutton Park, QLD 4102, Australia
| | - Peter Thomas-Hall
- Australian Institute of Marine Science (AIMS), Townsville, QLD 4810, Australia
| | - Lee Bastin
- Australian Institute of Marine Science (AIMS), Townsville, QLD 4810, Australia
| | - Dione J Deaker
- Marine Studies Institute, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Cherie A Motti
- Australian Institute of Marine Science (AIMS), Townsville, QLD 4810, Australia
| | - Maria Byrne
- Marine Studies Institute, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - David J Beale
- Land and Water, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Ecosciences Precinct, Dutton Park, QLD 4102, Australia.
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6
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Mita M, Osugi T, Kawada T, Satake H, Katayama H, Kitamura T, Miura T, Miura C. Characterization and localization of relaxin-like gonad-stimulating peptide in the crown-of-thorns starfish, Acanthaster cf. solaris. Gen Comp Endocrinol 2022; 328:114107. [PMID: 35973586 DOI: 10.1016/j.ygcen.2022.114107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 07/27/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022]
Abstract
In starfish, a relaxin-like gonad-stimulating peptide (RGP) is the gonadotropin responsible for final gamete maturation. RGP comprises two different peptides, A- and B-chains with two interchain and one intrachain disulfide bonds. The existence of two isomers of RGP in the crown-of-thorns starfish, Acanthaster planci, has been reported previously, but it was recently shown that A. planci represents a species complex with four different species. Here we elucidated the authentic sequence of the Pacific species, Acanthaster cf. solaris, RGP (Aso-RGP). The Aso-RGP precursor encoded by a 354 base pair open reading frame was composed of 117 amino acids (aa). The amino acid identity of Aso-RGP to Patiria pectinifera RGP (Ppe-RGP) and Asterias amurensis RGP (Aam-RGP) was 74% and 60%, respectively. Synthetic Aso-RGP induced spawning of ovarian fragments from A. cf. solaris. Ppe-RGP and Aam-RGP also induced spawning by A. cf. solaris ovaries. In contrast, Ppe-RGP and Aso-RGP induced spawning by P. pectinifera ovaries, but Aam-RGP was inactive. Notably, anti-Ppe-RGP antibodies recognized Aso-RGP as well as Ppe-RGP. Localization of Aso-RGP was observed immunohistochemically using anti-Ppe-RGP antibodies, showing that Aso-RGP was mainly present in the radial nerve cords of A. cf. solaris. Aso-RGP was distributed not only in the epithelium of the ectoneural region but also in the neuropile of the ectoneural region. These results suggest that Aso-RGP is synthesized in the epithelium of the ectoneural region, then transferred to fibers in the neuropile of the ectoneural region in radial nerve cords.
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Affiliation(s)
- Masatoshi Mita
- Department of Biochemistry, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
| | - Tomohiro Osugi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Tsuyoshi Kawada
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, 8-1-1 Seikadai, Seika-cho, Soraku-gun, Kyoto 619-0284, Japan
| | - Hidekazu Katayama
- Department of Applied Biochemistry, School of Engineering, Tokai University, 4-1-1, Kitakaname, Hiratsuka, Kanagawa 259-1292, Japan
| | - Takaya Kitamura
- The Kuroshio Biological Research Foundation, Nishidomari, Otsuki-cho, Hata-gun, Kochi 788-0333, Japan
| | - Takeshi Miura
- Laboratory of Aquaculture and Livestock Production, The United Graduate School of Agricultural Science, Ehime University, Tarumi 3-5-7, Matuyama-shi, Ehime 790-8566, Japan
| | - Chiemi Miura
- Department of Global Environmental Studies, Faculty of Environmental Studies, Hiroshima Institute of Technology, Miyake 2-1-1, Saeki-ku, Hiroshima 731-5193, Japan
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Oulhen N, Byrne M, Duffin P, Gomez-Chiarri M, Hewson I, Hodin J, Konar B, Lipp EK, Miner BG, Newton AL, Schiebelhut LM, Smolowitz R, Wahltinez SJ, Wessel GM, Work TM, Zaki HA, Wares JP. A Review of Asteroid Biology in the Context of Sea Star Wasting: Possible Causes and Consequences. THE BIOLOGICAL BULLETIN 2022; 243:50-75. [PMID: 36108034 PMCID: PMC10642522 DOI: 10.1086/719928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
AbstractSea star wasting-marked in a variety of sea star species as varying degrees of skin lesions followed by disintegration-recently caused one of the largest marine die-offs ever recorded on the west coast of North America, killing billions of sea stars. Despite the important ramifications this mortality had for coastal benthic ecosystems, such as increased abundance of prey, little is known about the causes of the disease or the mechanisms of its progression. Although there have been studies indicating a range of causal mechanisms, including viruses and environmental effects, the broad spatial and depth range of affected populations leaves many questions remaining about either infectious or non-infectious mechanisms. Wasting appears to start with degradation of mutable connective tissue in the body wall, leading to disintegration of the epidermis. Here, we briefly review basic sea star biology in the context of sea star wasting and present our current knowledge and hypotheses related to the symptoms, the microbiome, the viruses, and the associated environmental stressors. We also highlight throughout the article knowledge gaps and the data needed to better understand sea star wasting mechanistically, its causes, and potential management.
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Affiliation(s)
- Nathalie Oulhen
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Maria Byrne
- School of Life and Environmental Sciences, University of Sydney, Sydney, New South Wales, Australia
| | - Paige Duffin
- Department of Genetics, University of Georgia, Athens, Georgia
| | - Marta Gomez-Chiarri
- Department of Fisheries, Animal, and Veterinary Science, University of Rhode Island, Kingston, Rhode Island
| | - Ian Hewson
- Department of Microbiology, Cornell University, Ithaca, New York
| | - Jason Hodin
- Friday Harbor Labs, University of Washington, Friday Harbor, Washington
| | - Brenda Konar
- College of Fisheries and Ocean Sciences, University of Alaska, Fairbanks, Alaska
| | - Erin K. Lipp
- Department of Environmental Health Science, University of Georgia, Athens, Georgia
| | - Benjamin G. Miner
- Department of Biology, Western Washington University, Bellingham, Washington
| | | | - Lauren M. Schiebelhut
- Department of Life and Environmental Sciences, University of California, Merced, California
| | - Roxanna Smolowitz
- Department of Biology and Marine Biology, Roger Williams University, Bristol, Rhode Island
| | - Sarah J. Wahltinez
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, Florida
| | - Gary M. Wessel
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - Thierry M. Work
- US Geological Survey, National Wildlife Health Center, Honolulu Field Station, Honolulu, Hawaii
| | - Hossam A. Zaki
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, Rhode Island
| | - John P. Wares
- Department of Genetics, University of Georgia, Athens, Georgia
- Odum School of Ecology, University of Georgia, Athens, Georgia
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Culling corallivores improves short-term coral recovery under bleaching scenarios. Nat Commun 2022; 13:2520. [PMID: 35534497 PMCID: PMC9085818 DOI: 10.1038/s41467-022-30213-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 04/21/2022] [Indexed: 12/02/2022] Open
Abstract
Management of coral predators, corallivores, is recommended to improve coral cover on tropical coral reefs under projected increasing levels of accumulated thermal stress, but whether corallivore management can improve coral cover, which is necessary for large-scale operationalisation, remains equivocal. Here, using a multispecies ecosystem model, we investigate intensive management of an invertebrate corallivore, the Crown-of-Thorns Starfish (Acanthaster cf. solaris), and show that culling could improve coral cover at sub-reef spatial scales, but efficacy varied substantially within and among reefs. Simulated thermal stress events attenuated management-derived coral cover improvements and was dependent on the level of accumulated thermal stress, the thermal sensitivity of coral communities and the rate of corallivore recruitment at fine spatial scales. Corallivore management was most effective when accumulated thermal stress was low, coral communities were less sensitive to heat stress and in areas of high corallivore recruitment success. Our analysis informs how to manage a pest species to promote coral cover under future thermal stress events. This study uses multispecies modelling to show that the management of a coral predator, the crown-of-thorns starfish, could help corals recover following bleaching events. They show that management was most effective when heat stress severity for corals was low to moderate, when corals had lower heat sensitivity and when the recruitment rate of starfish was high.
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Tea YK, Najeeb A, Rowlett J, Rocha LA. Cirrhilabrus finifenmaa (Teleostei, Labridae), a new species of fairy wrasse from the Maldives, with comments on the taxonomic identity of C. rubrisquamis and C. wakanda. Zookeys 2022; 1088:65-80. [PMID: 35437369 PMCID: PMC8924139 DOI: 10.3897/zookeys.1088.78139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/14/2022] [Indexed: 11/12/2022] Open
Abstract
Cirrhilabrus rubrisquamis is redescribed on the basis of the juvenile holotype and compared to known species of Cirrhilabrus. Examination of material from the Maldives identified as C. rubrisquamis reveal differences from the holotype collected from the Chagos Archipelago. Consequently, the Maldivian specimens are herein described as Cirrhilabrus finifenmaasp. nov., on the basis of the holotype and twelve paratypes. The new species differs from all congeners in having: males with anterior third to half of body bright magenta, peach to orange-pink posteriorly; lateral line with 22–26 pored scales (16–18 in the dorso-anterior series, 6–8 in the posterior peduncular series); tenth to eleventh dorsal-fin spine longest (14.0–15.5% SL); scales on the opercle, chest, isthmus, and anterior third of the body with a dark purple-red central region (purple in alcohol), the markings joining appearing crosshatched; dorsal, caudal, anal, and pelvic-fin rays purple in alcohol. Meristic details and coloration patterns of C. rubrisquamis are very similar to C. wakanda from Tanzania, Africa, although synonymy of both species cannot be determined without additional material from Chagos. This potential synonymy is briefly discussed; however, until such material becomes available, the taxonomic statuses of C. wakanda and C. rubrisquamis are here provisionally regarded as valid.
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Kroeker KJ, Sanford E. Ecological Leverage Points: Species Interactions Amplify the Physiological Effects of Global Environmental Change in the Ocean. ANNUAL REVIEW OF MARINE SCIENCE 2022; 14:75-103. [PMID: 34416127 DOI: 10.1146/annurev-marine-042021-051211] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Marine ecosystems are increasingly impacted by global environmental changes, including warming temperatures, deoxygenation, and ocean acidification. Marine scientists recognize intuitively that these environmental changes are translated into community changes via organismal physiology. However, physiology remains a black box in many ecological studies, and coexisting species in a community are often assumed to respond similarly to environmental stressors. Here, we emphasize how greater attention to physiology can improve our ability to predict the emergent effects of ocean change. In particular, understanding shifts in the intensity and outcome of species interactions such as competition and predation requires a sharpened focus on physiological variation among community members and the energetic demands and trophic mismatches generated by environmental changes. Our review also highlights how key species interactions that are sensitive to environmental change can operate as ecological leverage points through which small changes in abiotic conditions are amplified into large changes in marine ecosystems.
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Affiliation(s)
- Kristy J Kroeker
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California 95064, USA;
| | - Eric Sanford
- Bodega Marine Laboratory, University of California, Davis, Bodega Bay, California 94923, USA;
- Department of Evolution and Ecology, University of California, Davis, California 95616, USA
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11
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Hart MW, Guerra VI, Allen JD, Byrne M. Cloning and Selfing Affect Population Genetic Variation in Simulations of Outcrossing, Sexual Sea Stars. THE BIOLOGICAL BULLETIN 2021; 241:286-302. [PMID: 35015625 DOI: 10.1086/717293] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
AbstractMany sea stars are well known for facultative or obligate asexual reproduction in both the adult and larval life-cycle stages. Some species and lineages are also capable of facultative or obligate hermaphroditic reproduction with self-fertilization. However, models of population genetic variation and empirical analyses of genetic data typically assume only sexual reproduction and outcrossing. A recent reanalysis of previously published empirical data (microsatellite genotypes) from two studies of one of the most well-known sea star species (the crown-of-thorns sea star; Acanthaster sp.) concluded that cloning and self-fertilization in that species are rare and contribute little to patterns of population genetic variation. Here we reconsider that conclusion by simulating the contribution of cloning and selfing to genetic variation in a series of models of sea star demography. Simulated variation in two simple models (analogous to previous analyses of empirical data) was consistent with high rates of cloning or selfing or both. More realistic scenarios that characterize population flux in sea stars of ecological significance, including outbreaks of crown-of-thorns sea stars that devastate coral reefs, invasions by Asterias amurensis, and epizootics of sea star wasting disease that kill Pisaster ochraceus, also showed significant but smaller effects of cloning and selfing on variation within subpopulations and differentiation between subpopulations. Future models or analyses of genetic variation in similar study systems might benefit from simulation modeling to characterize possible contributions of cloning or selfing to genetic variation in population samples or to understand the limits on inferring the effects of cloning or selfing in nature.
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Deaker DJ, Balogh R, Dworjanyn SA, Mos B, Byrne M. Echidnas of the Sea: The Defensive Behavior of Juvenile and Adult Crown-of-Thorns Sea Stars. THE BIOLOGICAL BULLETIN 2021; 241:259-270. [PMID: 35015617 DOI: 10.1086/716777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
AbstractCrown-of-thorns sea stars are one of the most ecologically important tropical marine invertebrates, with boom-bust population dynamics that influence the community structure of coral reefs. Although predation is likely to influence the development of population outbreaks, little is known about the defensive behavior of crown-of-thorns sea stars. Righting behavior after being overturned, a key defensive response in echinoderms, was investigated for the newly settled herbivorous juvenile, the corallivorous juvenile, and adult stages of crown-of-thorns sea stars. The average righting time of the newly settled juveniles (0.3-1.0-mm diameter) was 2.74 minutes. For the coral-eating juveniles (15-55-mm diameter), the righting time (mean = 6.24 min) was faster in larger juveniles, and the mean righting time of the adults was 6.28 minutes. During righting and in response to being lifted off of the substrate, the juveniles and adults exhibited an arm curling response, during which their arms closed over their oral side, often forming a spine ball, a feature not known for other asteroids. The righting and curling responses of the corallivorous juveniles were influenced by the presence of a natural enemy, a coral guard crab, which caused the juveniles to spend more time with their arms curled. These behaviors indicate that crown-of-thorns sea stars use their spines to protect the soft tissue of their oral side. The highly defended morphology and behavioral adaptations of crown-of-thorns sea stars are likely to have evolved as antipredator mechanisms. This points to the potential importance of predators in regulating their populations, which may have decreased in recent times due to fishing, a factor that may contribute to outbreaks.
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Lang BJ, Donelson JM, Caballes CF, Doll PC, Pratchett MS. Metabolic Responses of Pacific Crown-of-Thorns Sea Stars ( Acanthaster sp.) to Acute Warming. THE BIOLOGICAL BULLETIN 2021; 241:347-358. [PMID: 35015619 DOI: 10.1086/717049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
AbstractClimate change and population irruptions of crown-of-thorns sea stars (Acanthaster sp.) are two of the most pervasive threats to coral reefs. Yet there has been little consideration regarding the synergies between ocean warming and the coral-feeding sub-adult and adult stages of this asteroid. Here we explored the thermosensitivity of the aforementioned life stages by assessing physiological responses to acute warming. Thermal sensitivity was assessed based on the maximal activity of enzymes involved in aerobic (citrate synthase) and anaerobic (lactate dehydrogenase) metabolic pathways, as well as the standard metabolic rate of sub-adult and adult sea stars. In both life stages, citrate synthase activity declined with increasing temperature from 15 °C to 40 °C, with negligible activity occurring >35 °C. On the other hand, lactate dehydrogenase activity increased with temperature from 20 °C to 45 °C, indicating a greater reliance on anaerobic metabolism in a warmer environment. The standard metabolic rate of sub-adult sea stars increased with temperature throughout the testing range (24 °C to 36 °C). Adult sea stars exhibited evidence of thermal stress, with metabolic depression occurring from 33 °C. Here, we demonstrate that crown-of-thorns sea stars are sensitive to warming but that adults, and especially sub-adults, may have some resilience to short-term marine heatwaves in the near future.
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Yuasa H, Kajitani R, Nakamura Y, Takahashi K, Okuno M, Kobayashi F, Shinoda T, Toyoda A, Suzuki Y, Thongtham N, Forsman Z, Bronstein O, Seveso D, Montalbetti E, Taquet C, Eyal G, Yasuda N, Itoh T. Elucidation of the speciation history of three sister species of crown-of-thorns starfish (Acanthaster spp.) based on genomic analysis. DNA Res 2021; 28:6350483. [PMID: 34387305 DOI: 10.1093/dnares/dsab012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Indexed: 11/14/2022] Open
Abstract
The crown-of-thorns starfish (COTS) is a coral predator that is widely distributed in Indo-Pacific Oceans. A previous phylogenetic study using partial mitochondrial sequences suggested that COTS had diverged into four distinct species, but a nuclear genome-based analysis to confirm this was not conducted. To address this, COTS species nuclear genome sequences were analysed here, sequencing Northern Indian Ocean (NIO) and Red Sea (RS) species genomes for the first time, followed by a comparative analysis with the Pacific Ocean (PO) species. Phylogenetic analysis and ADMIXTURE analysis revealed clear divergences between the three COTS species. Furthermore, within the PO species, the phylogenetic position of the Hawaiian sample was further away from the other Pacific-derived samples than expected based on the mitochondrial data, suggesting that it may be a PO subspecies. The pairwise sequentially Markovian coalescent model showed that the trajectories of the population size diverged by region during the Mid-Pleistocene transition when the sea-level was dramatically decreased, strongly suggesting that the three COTS species experienced allopatric speciation. Analysis of the orthologues indicated that there were remarkable genes with species-specific positive selection in the genomes of the PO and RS species, which suggested that there may be local adaptations in the COTS species.
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Affiliation(s)
- Hideaki Yuasa
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Rei Kajitani
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Yuta Nakamura
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Kazuki Takahashi
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Miki Okuno
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Fumiya Kobayashi
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Takahiro Shinoda
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Atsushi Toyoda
- Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima City, Shizuoka 411-8540, Japan
| | - Yutaka Suzuki
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa-shi, Chiba 272-8562, Japan
| | | | - Zac Forsman
- Hawai'i Institute of Marine Biology, School of Ocean & Earth Sciences & Technology, University of Hawai'i at Mānoa, Coconut Island, Kāne'ohe, HI, USA
| | - Omri Bronstein
- George S. Wise Faculty of Life Sciences, School of Zoology, Tel Aviv University, Tel Aviv 6997801, Israel.,The Steinhardt Museum of Natural History, Israel National Center for Biodiversity Studies, Tel-Aviv University, Tel-Aviv 6997801, Israel
| | - Davide Seveso
- Department of Earth and Environmental Sciences (DISAT), University of Milano-Bicocca, 20126 Milan, Italy.,Marine Research and High Education Center (MaRHE Center), 12030 Faafu Magoodhoo, Republic of Maldives
| | - Enrico Montalbetti
- Department of Earth and Environmental Sciences (DISAT), University of Milano-Bicocca, 20126 Milan, Italy.,Marine Research and High Education Center (MaRHE Center), 12030 Faafu Magoodhoo, Republic of Maldives
| | | | - Gal Eyal
- ARC Centre of Excellence for Coral Reef Studies, School of Biological Sciences, University of Queensland, St. Lucia, QLD 4072, Australia.,The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Nina Yasuda
- Faculty of Agriculture, University of Miyazaki, Miyazaki, Miyazaki 889-2192, Japan
| | - Takehiko Itoh
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
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15
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Deaker DJ, Mos B, Lin HA, Lawson C, Budden C, Dworjanyn SA, Byrne M. Diet flexibility and growth of the early herbivorous juvenile crown-of-thorns sea star, implications for its boom-bust population dynamics. PLoS One 2020; 15:e0236142. [PMID: 32687524 PMCID: PMC7371202 DOI: 10.1371/journal.pone.0236142] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 06/29/2020] [Indexed: 11/18/2022] Open
Abstract
The ecology of the early herbivorous juvenile stage of the crown-of-thorns sea star (COTS, Acanthaster spp.) is poorly understood, yet the success of this life stage is key to generating population outbreaks that devastate coral reefs. Crustose coralline algae (CCA) has been considered to be the main diet of herbivorous juveniles. In this study, we show that COTS can avail of a range of algal food. Juveniles were reared on CCA, Amphiroa sp., and biofilm, and survived for 10 months on all three diets. The juveniles fed CCA and Amphiroa sp. reached 15–16.5 mm diameter at ~ 6 months and maintained this size for the rest the experiment (an additional ~4 months). Juveniles fed biofilm grew more slowly and to a smaller maximum size (~3 mm diameter). However, when juveniles were switched from biofilm to CCA they resumed growth to a new asymptotic size (~13.5 mm, 13–20 months). In diet choice experiments, juveniles did not show a preference between Amphiroa sp. and CCA, but generally avoided biofilm. Our results show that juvenile COTS grew equally well on CCA and Amphiroa sp. and can subsist on biofilm for months. Some juveniles, mostly from the biofilm diet treatment, decreased in size for a time and this was followed by recovery. Flexibility in diet, growth, and prolonged maintenance of asymptotic size indicates capacity for growth plasticity in herbivorous juvenile COTS. There is potential for juvenile COTS to persist for longer than anticipated and increase in number as they wait for the opportunity to avail of coral prey. These findings complicate our ability to predict recruitment to the corallivorous stage and population outbreaks following larval settlement and the ability to understand the age structure of COTS populations.
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Affiliation(s)
- Dione J. Deaker
- School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia
- * E-mail:
| | - Benjamin Mos
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
| | - Huang-An Lin
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
| | - Corinne Lawson
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
| | - Claire Budden
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
| | - Symon A. Dworjanyn
- National Marine Science Centre, School of Environment, Science and Engineering, Southern Cross University, Coffs Harbour, New South Wales, Australia
| | - Maria Byrne
- School of Medical Sciences, The University of Sydney, Sydney, New South Wales, Australia
- School of Life and Environmental Sciences, The University of Sydney, Sydney, New South Wales, Australia
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16
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Burn D, Matthews S, Caballes CF, Chandler JF, Pratchett MS. Biogeographical variation in diurnal behaviour of Acanthaster planci versus Acanthaster cf. solaris. PLoS One 2020; 15:e0228796. [PMID: 32078663 PMCID: PMC7032693 DOI: 10.1371/journal.pone.0228796] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 01/22/2020] [Indexed: 11/24/2022] Open
Abstract
Crown-of-thorns starfish (CoTS; Acanthaster spp.) are among the most extensively studied coral reef taxa, largely owing to their devastating impacts on live coral cover during population outbreaks. Much of this research has however, been conducted in the western Pacific, although it is now apparent that there are several distinct species of Acanthaster spp. across the Indo-Pacific. The purpose of this study was to test for biogeographical variation in behaviour, comparing between Acanthaster planci at Lankanfushi Island in the Maldives and Acanthaster cf. solaris at Rib Reef on Australia's Great Barrier Reef. The extent to which CoTS were exposed (cf. concealed within or beneath coral substrates) was substantially higher (63.14%) for A. planci at Lankanfushi Island, compared to 28.55% for A. cf. solaris at Rib Reef, regardless of time of day. More importantly, only 52% of individuals were exposed at night at Rib Reef compared to >97% at reefs around Lankanfushi Island. Biogeographic variation in the behaviour of Acanthaster spp. was independent of differences in the size structure of starfish and coral cover at specific study sites, but may be attributable to other environmental factors such as habitat complexity or prey availability. This is the first study to explicitly test for biogeographical differences in the biology and behaviour of Acanthaster spp., potentially linked to species-specific differences in the causes and explanations of population outbreaks. However, we did not find evidence at this stage of differences in behavior among regions, rather behavioural differences observed were most likely products of different environments.
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Affiliation(s)
- Deborah Burn
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
| | - Samuel Matthews
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
| | - Ciemon F. Caballes
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
- Ultra Coral Australia, Paget, Queensland, Australia
| | - Josie F. Chandler
- Gili Lankanfushi Resort, Lankanfushi Island, North Male Atoll, Maldives
| | - Morgan S. Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia
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17
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Guerra V, Haynes G, Byrne M, Yasuda N, Adachi S, Nakamura M, Nakachi S, Hart MW. Nonspecific expression of fertilization genes in the crown-of-thorns Acanthaster cf. solaris: Unexpected evidence of hermaphroditism in a coral reef predator. Mol Ecol 2019; 29:363-379. [PMID: 31837059 DOI: 10.1111/mec.15332] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 11/28/2019] [Accepted: 12/10/2019] [Indexed: 01/04/2023]
Abstract
The characterization of gene expression in gametes has advanced our understanding of the molecular basis for ecological variation in reproductive success and the evolution of reproductive isolation. These advances are especially significant for ecologically important keystone predators such as the coral-eating crown-of-thorns sea stars (COTS, Acanthaster) which are the most influential predator species in Indo-Pacific coral reef ecosystems and the focus of intensive management efforts. We used RNA-seq and transcriptome assemblies to characterize the expression of genes in mature COTS gonads. We described the sequence and domain organization of eight genes with sex-specific expression and well known functions in fertilization in other echinoderms. We found unexpected expression of genes in one ovary transcriptome that are characteristic of males and sperm, including genes that encode the sperm-specific guanylate cyclase receptor for an egg pheromone, and the sperm acrosomal protein bindin. In a reassembly of previously published RNA-seq data from COTS testes, we found a complementary pattern: strong expression of four genes that are otherwise well known to encode egg-specific fertilization proteins, including the egg receptor for bindin (EBR1) and the acrosome reaction-inducing substance in the egg coat (ARIS1, ARIS2, ARIS3). We also found histological evidence of both eggs and sperm developing in the same gonad in several COTS individuals from a parallel study. These results suggest the occurrence of hermaphrodites, and the potential for reproductive assurance via self-fertilization. Our findings have implications for management of COTS populations, especially in consideration of the large size and massive fecundity of these sea stars.
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Affiliation(s)
- Vanessa Guerra
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada.,Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - Gwilym Haynes
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada.,Department of Biology, Langara College, Vancouver, British Columbia, Canada
| | - Maria Byrne
- Schools of Medical and Biological Sciences, The University of Sydney, Sydney, Australia
| | - Nina Yasuda
- Department of Marine Biology and Environmental Science, Faculty of Agriculture, University of Miyazaki, Miyazaki, Japan
| | - Souta Adachi
- School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka, Japan
| | - Masako Nakamura
- School of Marine Science and Technology, Tokai University, Shimizu, Shizuoka, Japan
| | | | - Michael W Hart
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
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18
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Roberts RE, Powell D, Wang T, Hall MH, Motti CA, Cummins SF. Putative chemosensory receptors are differentially expressed in the sensory organs of male and female crown-of-thorns starfish, Acanthaster planci. BMC Genomics 2018; 19:853. [PMID: 30497381 PMCID: PMC6267866 DOI: 10.1186/s12864-018-5246-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 11/14/2018] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Chemosensation is a critical signalling process for all organisms and is achieved through the interaction between chemosensory receptors and their ligands. The Crown-of-thorns starfish, Acanthaster planci species complex (COTS), is a predator of coral polyps and Acanthaster cf. solaris is currently considered to be one of the main drivers of coral loss on the Great Barrier Reef in Queensland, Australia. RESULTS This study reveals the presence of putative variant Ionotropic Receptors (IRs) which are differentially expressed in the olfactory organs of COTS. Several other types of G protein-coupled receptors such as adrenergic, metabotropic glutamate, cholecystokinin, trace-amine associated, GRL101 and GPCR52 receptors have also been identified. Several receptors display male-biased expression within the sensory tentacles, indicating possible reproductive significance. CONCLUSIONS Many of the receptors identified in this study may have a role in reproduction and are therefore key targets for further investigation. Based on their differential expression within the olfactory organs and presence in multiple tissues, it is possible that several of these receptor types have expanded within the Echinoderm lineage. Many are likely to be species-specific with novel ligand-binding affinity and a diverse range of functions. This study is the first to describe the presence of variant Ionotropic Glutamate Receptors in any Echinoderm, and is only the second study to investigate chemosensory receptors in any starfish or marine pest. These results represent a significant step forward in understanding the chemosensory abilities of COTS.
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Affiliation(s)
- R. E. Roberts
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, QLD 4558 Australia
| | - D. Powell
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, QLD 4558 Australia
| | - T. Wang
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, QLD 4558 Australia
| | - M. H. Hall
- Australian Institute of Marine Science (AIMS), Cape Ferguson, Townsville, QLD 4810 Australia
| | - C. A. Motti
- Australian Institute of Marine Science (AIMS), Cape Ferguson, Townsville, QLD 4810 Australia
| | - S. F. Cummins
- Genecology Research Centre, Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Maroochydore DC, QLD 4558 Australia
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19
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Lowe EK, Garm AL, Ullrich-Lüter E, Cuomo C, Arnone MI. The crowns have eyes: multiple opsins found in the eyes of the crown-of-thorns starfish Acanthaster planci. BMC Evol Biol 2018; 18:168. [PMID: 30419810 PMCID: PMC6233551 DOI: 10.1186/s12862-018-1276-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 10/18/2018] [Indexed: 01/01/2023] Open
Abstract
Background Opsins are G protein-coupled receptors used for both visual and non-visual photoreception, and these proteins evolutionarily date back to the base of the bilaterians. In the current sequencing age, phylogenomic analysis has proven to be a powerful tool, facilitating the increase in knowledge about diversity within the opsin subclasses and, so far, at least nine types of opsins have been identified. Within echinoderms, opsins have been studied in Echinoidea and Ophiuroidea, which do not possess proper image forming eyes, but rather widely dispersed dermal photoreceptors. However, most species of Asteroidea, the starfish, possess true eyes and studying them will shed light on the diversity of opsin usage within echinoderms and help resolve the evolutionary history of opsins. Results Using high-throughput RNA sequencing, we have sequenced and analyzed the transcriptomes of different Acanthaster planci tissue samples: eyes, radial nerve, tube feet and a mixture of tissues from other organs. At least ten opsins were identified, and eight of them were found significantly differentially expressed in both eyes and radial nerve, with R-opsin being the most highly expressed in the eye. Conclusion This study provides new important insight into the involvement of opsins in visual and nonvisual photoreception. Of relevance, we found the first indication of an r-opsin photopigment expressed in a well-developed visual eye in a deuterostome animal. Additionally, we provided tissue specific A. planci transcriptomes that will aid in future Evo Devo studies. Electronic supplementary material The online version of this article (10.1186/s12862-018-1276-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Elijah K Lowe
- Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa comunale, 80122, Naples, Italy
| | - Anders L Garm
- Marine Biological Section, University of Copenhagen, Copenhagen, Denmark
| | | | - Claudia Cuomo
- Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa comunale, 80122, Naples, Italy
| | - Maria I Arnone
- Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Villa comunale, 80122, Naples, Italy.
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20
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Heery EC, Hoeksema BW, Browne NK, Reimer JD, Ang PO, Huang D, Friess DA, Chou LM, Loke LHL, Saksena-Taylor P, Alsagoff N, Yeemin T, Sutthacheep M, Vo ST, Bos AR, Gumanao GS, Syed Hussein MA, Waheed Z, Lane DJW, Johan O, Kunzmann A, Jompa J, Taira D, Bauman AG, Todd PA. Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia. MARINE POLLUTION BULLETIN 2018; 135:654-681. [PMID: 30301085 DOI: 10.1016/j.marpolbul.2018.07.041] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 07/10/2018] [Accepted: 07/16/2018] [Indexed: 05/28/2023]
Abstract
Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including "reef compression" (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas.
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Affiliation(s)
- Eliza C Heery
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Bert W Hoeksema
- Taxonomy and Systematics Group, Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, the Netherlands; Institute of Biology Leiden, Leiden University, P.O. Box 9505, 2300 RA Leiden, the Netherlands.
| | - Nicola K Browne
- Molecular and Life Sciences, Faculty of Science and Engineering, Bentley Campus, Curtin University, Perth, WA 6102, Australia; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - James D Reimer
- Molecular Invertebrate Systematics and Ecology Laboratory, Department of Biology, Chemistry and Marine Sciences, Faculty of Science, University of the Ryukyus, Nishihara, Okinawa, Japan; Tropical Biosphere Research Center, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Put O Ang
- Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Danwei Huang
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore; Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
| | - Daniel A Friess
- Department of Geography, National University of Singapore, Singapore 117570, Singapore; Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Loke Ming Chou
- Tropical Marine Science Institute, National University of Singapore, Singapore 119227, Singapore
| | - Lynette H L Loke
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Poonam Saksena-Taylor
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Nadia Alsagoff
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Thamasak Yeemin
- Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University, Huamark, Bangkok 10240, Thailand
| | - Makamas Sutthacheep
- Marine Biodiversity Research Group, Department of Biology, Faculty of Science, Ramkhamhaeng University, Huamark, Bangkok 10240, Thailand
| | - Si Tuan Vo
- Institute of Oceanography, Vietnam Academy of Science and Technology, 1 Cau Da, Nha Trang, Khanh Hoa, Viet Nam
| | - Arthur R Bos
- Department of Biology, The American University in Cairo, P.O. Box 74, New Cairo 11835, Egypt; Taxonomy and Systematics Group, Naturalis Biodiversity Center, P.O. Box 9517, 2300 RA Leiden, the Netherlands
| | - Girley S Gumanao
- Marine Biology Department, Davao del Norte State College, New Visayas, 8105 Panabo City, the Philippines
| | - Muhammad Ali Syed Hussein
- Endangered Marine Species Research Unit, Borneo Marine Research Institute, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia
| | - Zarinah Waheed
- Endangered Marine Species Research Unit, Borneo Marine Research Institute, Universiti Malaysia Sabah, 88400 Kota Kinabalu, Sabah, Malaysia
| | - David J W Lane
- Lee Kong Chian Natural History Museum, Faculty of Science, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Singapore
| | - Ofri Johan
- Research Institute for Ornamental Fish Culture, Jl. Perikanan No. 13, Pancoran Mas, Kota Depok, Jawa Barat 16436, Indonesia
| | - Andreas Kunzmann
- Leibniz Center for Tropical Marine Research (ZMT), Fahrenheitstr. 6, 28359 Bremen, Germany
| | - Jamaluddin Jompa
- Department of Marine Science, Hasanuddin University, Makassar, Indonesia
| | - Daisuke Taira
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Andrew G Bauman
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore
| | - Peter A Todd
- Department of Biological Sciences, National University of Singapore, Singapore 117558, Singapore.
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21
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Wilmes JC, Caballes CF, Cowan ZL, Hoey AS, Lang BJ, Messmer V, Pratchett MS. Contributions of pre- versus post-settlement processes to fluctuating abundance of crown-of-thorns starfishes (Acanthaster spp.). MARINE POLLUTION BULLETIN 2018; 135:332-345. [PMID: 30301045 DOI: 10.1016/j.marpolbul.2018.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Revised: 06/27/2018] [Accepted: 07/02/2018] [Indexed: 06/08/2023]
Abstract
Numerous hypotheses have been put forward to account for population outbreaks of crown-of-thorns starfishes (CoTS, Acanthaster spp.), which place specific importance on either pre- or post-settlement mechanisms. The purpose of this review is to specifically assess the contributions of pre- versus post-settlement processes in the population dynamics of CoTS. Given the immense reproductive potential of CoTS (>100 million eggs per female), persistent high densities would appear inevitable unless there were significant constraints on larval development, settlement success, and/or early post-settlement growth and survival. In terms of population constraints, pre- and post-settlement processes are both important and have additive effects to suppress densities of juvenile and adult CoTS within reef ecosystems. It is difficult, however, to assess the relative contributions of pre- versus post-settlement processes to population outbreaks, especially given limited data on settlement rates, as well as early post-settlement growth and mortality. Prioritising this research is important to resolve potential effects of anthropogenic activities (e.g., fishing) and habitat degradation on changing population dynamics of CoTS, and will also improve management effectiveness.
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Affiliation(s)
- Jennifer C Wilmes
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; Red Fish Blue Fish Marine, Cairns, QLD 4870, Australia
| | - Ciemon F Caballes
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; Ultra Coral Australia, Paget, QLD 4740, Australia
| | - Zara-Louise Cowan
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia; School of Marine Science and Policy, University of Delaware, Lewes, DE 19958, USA
| | - Andrew S Hoey
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Bethan J Lang
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Vanessa Messmer
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia
| | - Morgan S Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811, Australia.
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22
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Crown-of-Thorns Sea Star Acanthaster cf. solaris Has Tissue-Characteristic Microbiomes with Potential Roles in Health and Reproduction. Appl Environ Microbiol 2018; 84:AEM.00181-18. [PMID: 29728381 PMCID: PMC6007096 DOI: 10.1128/aem.00181-18] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/20/2018] [Indexed: 11/20/2022] Open
Abstract
Outbreaks of coral-eating crown-of-thorns sea stars (CoTS; Acanthaster species complex) cause substantial coral loss; hence, there is considerable interest in developing prevention and control strategies. We characterized the microbiome of captive CoTS and assessed whether dysbiosis was evident in sea stars during a disease event. Most tissue types had a distinct microbiome. The exception was female gonads, in which the microbiomes were highly variable among individuals. Male gonads were dominated (>97% of reads) by a single Mollicutes-related operational taxonomic unit (OTU). Detailed phylogenetic and microscopy analysis demonstrated the presence of a novel Spiroplasma-related bacterium in the spermatogenic layer. Body wall samples had high relative abundance (43 to 64% of reads) of spirochetes, likely corresponding to subcuticular symbionts reported from many echinoderms. Tube feet were characterized by Hyphomonadaceae (24 to 55% of reads). Pyloric cecal microbiomes had high alpha diversity, comprising many taxa commonly found in gastrointestinal systems. The order Oceanospirillales (genera Endozoicomonas and Kistimonas) was detected in all tissues. A microbiome shift occurred in diseased individuals although differences between tissue types were retained. The relative abundance of spirochetes was significantly reduced in diseased individuals. Kistimonas was present in all diseased individuals and significantly associated with diseased tube feet, but its role in disease causation is unknown. While Arcobacter was significantly associated with diseased tissues and Vibrionaceae increased in diversity, no single OTU was detected in all diseased individuals, suggesting opportunistic proliferation of these taxa in this case. This study shows that CoTS have tissue-characteristic bacterial communities and identifies taxa that could play a role in reproduction and host health. IMPORTANCE Coral-eating crown-of-thorns sea stars (CoTS; Acanthaster species complex) are native to the Indo-Pacific, but during periodic population outbreaks they can reach extreme densities (>1,000 starfish per hectare) and function as a pest species. On the Great Barrier Reef, Australia, CoTS have long been considered one of the major contributors to coral loss. There has been significant investment in a targeted control program using lethal injection, and there is interest in developing additional and complementary technologies that can increase culling efficiencies. The biology of CoTS has been studied extensively, but little is known about their associated microbiome. This cultivation-independent analysis of the CoTS microbiome provides a baseline for future analyses targeting the functional role of symbionts, the identification of pathogens, or the development of reproduction manipulators.
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23
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Loss of live coral compromises predator-avoidance behaviour in coral reef damselfish. Sci Rep 2018; 8:7795. [PMID: 29773843 PMCID: PMC5958076 DOI: 10.1038/s41598-018-26090-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 04/19/2018] [Indexed: 11/09/2022] Open
Abstract
Tropical reefs have experienced an unprecedented loss of live coral in the past few decades and the biodiversity of coral-dependent species is under threat. Many reef fish species decline in abundance as coral cover is lost, yet the mechanisms responsible for these losses are largely unknown. A commonly hypothesised cause of fish decline is the loss of shelter space between branches as dead corals become overgrown by algae. Here we tested this hypothesis by quantifying changes in predator-avoidance behaviour of a common damselfish, Pomacentrus moluccensis, before and after the death of their coral colony. Groups of P. moluccensis were placed on either healthy or degraded coral colonies, startled using a visual stimulus and their sheltering responses compared over a 7-week period. P. moluccensis stopped sheltering amongst the coral branches immediately following the death of the coral, despite the presence of ample shelter space. Instead, most individuals swam away from the dead coral, potentially increasing their exposure to predators. It appears that the presence of live coral rather than shelter per se is the necessary cue that elicits the appropriate behavioural response to potential predators. The disruption of this link poses an immediate threat to coral-associated fishes on degrading reefs.
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24
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Saponari L, Montalbetti E, Galli P, Strona G, Seveso D, Dehnert I, Montano S. Monitoring and assessing a 2-year outbreak of the corallivorous seastar Acanthaster planci in Ari Atoll, Republic of Maldives. ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:344. [PMID: 29754219 DOI: 10.1007/s10661-018-6661-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 04/04/2018] [Indexed: 06/08/2023]
Abstract
Outbreaks of the corallivorous crown-of-thorns seastars have received increasing attention due to their negative impacts on coral reefs in the Indo-Pacific Ocean. However, outbreaks in remote and dislocated islands are still poorly understood. This study aims to begin filling informational gaps regarding outbreaks of Acanthaster planci in the remote islands of the central Ari Atoll, Republic of Maldives. The population of A. planci was monitored during three periods over 2 years (2015-2016) to evaluate variations in abundance and to characterise size structure and feeding behaviour. The outbreak appeared to be severe and active throughout the entire study period. The size structure analysis revealed a multimodal distribution dominated by individuals between 20 and 30 cm, suggesting that the outbreak may have resulted from a few nearby mass spawning events. Additionally, the most abundant live coral was Porites, which was also the most consumed genus; however, the electivity index showed a preference for corals of the genera Favites and Pavona. Finally, we also highlighted the need for more geographically extended surveys to better understand local patterns regarding outbreaks of A. planci in the Republic of Maldives.
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Affiliation(s)
- Luca Saponari
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives.
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Piazza della Scienza, 20126, Milan, Italy.
| | - Enrico Montalbetti
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Piazza della Scienza, 20126, Milan, Italy
| | - Paolo Galli
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Piazza della Scienza, 20126, Milan, Italy
| | - Giovanni Strona
- European Commission, Joint Research Centre, Directorate D - Sustainable Resources, Bio-Economy Unit, Via Enrico Fermi 2749, 21027, Ispra, Italy
| | - Davide Seveso
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Piazza della Scienza, 20126, Milan, Italy
| | - Inga Dehnert
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives
| | - Simone Montano
- MaRHE Center (Marine Research and High Education Center), Magoodhoo Island, Faafu Atoll, Republic of Maldives
- Department of Earth and Environmental Sciences (DISAT), University of Milan - Bicocca, Piazza della Scienza, 20126, Milan, Italy
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25
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Chemical Ecology of Chemosensation in Asteroidea: Insights Towards Management Strategies of Pest Species. J Chem Ecol 2018; 44:147-177. [PMID: 29362949 DOI: 10.1007/s10886-018-0926-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 12/03/2017] [Accepted: 01/09/2018] [Indexed: 12/11/2022]
Abstract
Within the Phylum Echinodermata, the class Asteroidea, commonly known as starfish and sea stars, encompasses a large number of benthos inhabiting genera and species with various feeding modalities including herbivores, carnivores, omnivores and detritivores. The Asteroidea rely on chemosensation throughout their life histories including hunting prey, avoiding or deterring predators, in the formation of spawning aggregations, synchronizing gamete release and targeting appropriate locations for larval settlement. The identities of many of the chemical stimuli that mediate these physiological and behavioural processes remain unresolved even though evidence indicates they play pivotal roles in the functionality of benthic communities. Aspects of chemosensation, as well as putative chemically-mediated behaviours and the molecular mechanisms of chemoreception, within the Asteroidea are reviewed here, with particular reference to the coral reef pest the Crown-of-Thorns starfish Acanthaster planci species complex, in the context of mitigation of population outbreaks.
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26
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Uthicke S, Liddy M, Patel F, Logan M, Johansson C, Lamare M. Effects of larvae density and food concentration on Crown-of-Thorns seastar (Acanthaster cf. solaris) development in an automated flow-through system. Sci Rep 2018; 8:642. [PMID: 29330503 PMCID: PMC5766623 DOI: 10.1038/s41598-017-19132-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/21/2017] [Indexed: 02/01/2023] Open
Abstract
Coral-eating Crown-of-Thorns Sea stars (Acanthaster spp.) are major contributors to coral reef loss in the Indo-Pacific region. A release from food limitation of their planktotrophic larvae through enhanced pelagic productivity is one of the main hypothesis explaining population outbreaks (‘nutrient limitation hypothesis’). To improve the understanding of these outbreaks we developed an automated flow- through larvae rearing system that maintained food (microalgae) at set levels over the course of four 15d experiments. This resulted in stable food concentrations in experimental tanks. Increased algae concentrations had a significant positive effect on larval development and size at 10 and 15 days post fertilization (dpf). Larvae densities had no effect at 10 dpf. At 15 dpf greater larvae densities were associated with declines in larvae size. Larval development was slowed under higher larvae densities. Thus, the effects of algae concentration and larvae density were additive at 15 dpf, with larvae under low densities at a given algae concentration being further developed than those under higher densities. The development of a flow-through system gives greater insight into the effect of algae and larvae concentrations on Acanthaster development, and the system can be applied to further test the nutrient-limitation hypothesis for present and future outbreaks.
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Affiliation(s)
- S Uthicke
- Australian Institute of Marine Science, PMB No 3, Townsville, Queensland, 4810, Australia.
| | - M Liddy
- Department of Marine Science, University of Otago, 9016, Dunedin, New Zealand
| | - F Patel
- Australian Institute of Marine Science, PMB No 3, Townsville, Queensland, 4810, Australia
| | - M Logan
- Australian Institute of Marine Science, PMB No 3, Townsville, Queensland, 4810, Australia
| | - C Johansson
- Australian Institute of Marine Science, PMB No 3, Townsville, Queensland, 4810, Australia
| | - M Lamare
- Department of Marine Science, University of Otago, 9016, Dunedin, New Zealand
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27
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Thirty Years of Research on Crown-of-Thorns Starfish (1986–2016): Scientific Advances and Emerging Opportunities. DIVERSITY-BASEL 2017. [DOI: 10.3390/d9040041] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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28
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Pratchett MS, Cowan ZL, Nadler LE, Caballes CF, Hoey AS, Messmer V, Fletcher CS, Westcott DA, Ling SD. Body size and substrate type modulate movement by the western Pacific crown-of-thorns starfish, Acanthaster solaris. PLoS One 2017; 12:e0180805. [PMID: 28877193 PMCID: PMC5587101 DOI: 10.1371/journal.pone.0180805] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 06/21/2017] [Indexed: 11/25/2022] Open
Abstract
The movement capacity of the crown-of-thorns starfishes (Acanthaster spp.) is a primary determinant of both their distribution and impact on coral assemblages. We quantified individual movement rates for the Pacific crown-of-thorns starfish (Acanthaster solaris) ranging in size from 75–480 mm total diameter, across three different substrates (sand, flat consolidated pavement, and coral rubble) on the northern Great Barrier Reef. The mean (±SE) rate of movement for smaller (<150 mm total diameter) A. solaris was 23.99 ± 1.02 cm/ min and 33.41 ± 1.49 cm/ min for individuals >350 mm total diameter. Mean (±SE) rates of movement varied with substrate type, being much higher on sand (36.53 ± 1.31 cm/ min) compared to consolidated pavement (28.04 ± 1.15 cm/ min) and slowest across coral rubble (17.25 ± 0.63 cm/ min). If average rates of movement measured here can be sustained, in combination with strong directionality, displacement distances of adult A. solaris could range from 250–520 m/ day, depending on the prevailing substrate. Sustained movement of A. solaris is, however, likely to be highly constrained by habitat heterogeneity, energetic constraints, resource availability, and diurnal patterns of activity, thereby limiting their capacity to move between reefs or habitats.
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Affiliation(s)
- Morgan S. Pratchett
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
- * E-mail:
| | - Zara-Louise Cowan
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Lauren E. Nadler
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, United States of America
| | - Ciemon F. Caballes
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Andrew S. Hoey
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | - Vanessa Messmer
- ARC Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
| | | | | | - Scott D. Ling
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
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