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Edmunds PJ. Coral recruitment: patterns and processes determining the dynamics of coral populations. Biol Rev Camb Philos Soc 2023; 98:1862-1886. [PMID: 37340617 DOI: 10.1111/brv.12987] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 05/30/2023] [Accepted: 06/02/2023] [Indexed: 06/22/2023]
Abstract
Coral recruitment describes the addition of new individuals to populations, and it is one of the most fundamental demographic processes contributing to population size. As many coral reefs around the world have experienced large declines in coral cover and abundance, there has been great interest in understanding the factors causing coral recruitment to vary and the conditions under which it can support community resilience. While progress in these areas is being facilitated by technological and scientific advances, one of the best tools to quantify recruitment remains the humble settlement tile, variants of which have been in use for over a century. Here I review the biology and ecology of coral recruits and the recruitment process, largely as resolved through the use of settlement tiles, by: (i) defining how the terms 'recruit' and 'recruitment' have been used, and explaining why loose terminology has impeded scientific advancement; (ii) describing how coral recruitment is measured and why settlement tiles have value for this purpose; (iii) summarizing previous efforts to review quantitative analyses of coral recruitment; (iv) describing advances from hypothesis-driven studies in determining how refuges, seawater flow, and grazers can modulate coral recruitment; (v) reviewing the biology of small corals (i.e. recruits) to understand better how they respond to environmental conditions; and (vi) updating a quantitative compilation of coral recruitment studies extending from 1974 to present, thus revealing long-term global declines in density of recruits, juxtaposed with apparent resilience to coral bleaching. Finally, I review future directions in the study of coral recruitment, and highlight the need to expand studies to deliver taxonomic resolution, and explain why time series of settlement tile deployments are likely to remain pivotal in quantifying coral recruitment.
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Affiliation(s)
- Peter J Edmunds
- Department of Biology, California State University, 18111 Nordhoff Street, Northridge, CA, 91330-8303, USA
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Jacobson LM, Edmunds PJ, Muller EB, Nisbet RM. The implications of reduced metabolic rate in a resource-limited coral. J Exp Biol 2016; 219:870-7. [DOI: 10.1242/jeb.136044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/14/2016] [Indexed: 02/04/2023]
Abstract
Many organisms exhibit depressed metabolism when resources are limited, a change that makes it possible to balance an energy budget. For symbiotic reef corals, daily cycles of light and periods of intense cloud cover can be chronic causes of food limitation through reduced photosynthesis. Furthermore, coral bleaching is common in present day reefs, creating a context in which metabolic depression could have beneficial value to corals. In the present study, corals (massive Porites) were exposed to an extreme case of resource limitation by starving them of food and light for 20 d. When resources were limited, the corals depressed area-normalized respiration to 37% of initial rates, coral biomass declined to 64% of initial amounts, yet the corals continued to produce skeletal mass. However, the declines in biomass cannot account for the declines in area-normalized respiration, as mass-specific respiration declined to 30% of initial rates. Thus, these corals appear to be capable of metabolic depression. It is possible that some coral species are better able to depress metabolic rates, such variation could explain differential survival during conditions that limit resources (e.g., shading). Furthermore, we found that maintenance of existing biomass, in part, supports the production of skeletal mass. This association could be explained if maintenance supplies needed energy (e.g., ATP) or inorganic carbon (i.e., CO2) that otherwise limits the production of skeletal mass. Finally, the observed metabolic depression can be explained as change in pool sizes, and does not require a change in metabolic rules.
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Affiliation(s)
- Lianne M. Jacobson
- Department of Biology, California State University, Northridge, CA 91330, USA
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Peter J. Edmunds
- Department of Biology, California State University, Northridge, CA 91330, USA
| | - Erik B. Muller
- Marine Science Institute, University of California, Santa Barbara, CA 93106, USA
| | - Roger M. Nisbet
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA 93106, USA
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Edmunds PJ, Adjeroud M, Baskett ML, Baums IB, Budd AF, Carpenter RC, Fabina NS, Fan TY, Franklin EC, Gross K, Han X, Jacobson L, Klaus JS, McClanahan TR, O'Leary JK, van Oppen MJH, Pochon X, Putnam HM, Smith TB, Stat M, Sweatman H, van Woesik R, Gates RD. Persistence and change in community composition of reef corals through present, past, and future climates. PLoS One 2014; 9:e107525. [PMID: 25272143 PMCID: PMC4182679 DOI: 10.1371/journal.pone.0107525] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 08/20/2014] [Indexed: 11/18/2022] Open
Abstract
The reduction in coral cover on many contemporary tropical reefs suggests a different set of coral community assemblages will dominate future reefs. To evaluate the capacity of reef corals to persist over various time scales, we examined coral community dynamics in contemporary, fossil, and simulated future coral reef ecosystems. Based on studies between 1987 and 2012 at two locations in the Caribbean, and between 1981 and 2013 at five locations in the Indo-Pacific, we show that many coral genera declined in abundance, some showed no change in abundance, and a few coral genera increased in abundance. Whether the abundance of a genus declined, increased, or was conserved, was independent of coral family. An analysis of fossil-reef communities in the Caribbean revealed changes in numerical dominance and relative abundances of coral genera, and demonstrated that neither dominance nor taxon was associated with persistence. As coral family was a poor predictor of performance on contemporary reefs, a trait-based, dynamic, multi-patch model was developed to explore the phenotypic basis of ecological performance in a warmer future. Sensitivity analyses revealed that upon exposure to thermal stress, thermal tolerance, growth rate, and longevity were the most important predictors of coral persistence. Together, our results underscore the high variation in the rates and direction of change in coral abundances on contemporary and fossil reefs. Given this variation, it remains possible that coral reefs will be populated by a subset of the present coral fauna in a future that is warmer than the recent past.
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Affiliation(s)
- Peter J. Edmunds
- Department of Biology, California State University Northridge, Northridge, California, United States of America
| | - Mehdi Adjeroud
- Institut de Recherche pour le Développement, Unité de Recherche CoReUs, Observatoire Océanologique de Banyuls, Banyuls-sur-Mer, France
- Laboratoire d'Excellence "CORAIL", Perpignan, France
| | - Marissa L. Baskett
- Department of Environmental Science and Policy, University of California Davis, Davis, California, United States of America
| | - Iliana B. Baums
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Ann F. Budd
- Department of Earth and Environmental Sciences, University of Iowa, Iowa City, Iowa, United States of America
| | - Robert C. Carpenter
- Department of Biology, California State University Northridge, Northridge, California, United States of America
| | - Nicholas S. Fabina
- Center for Population Biology, University of California Davis, Davis, California, United States of America
| | - Tung-Yung Fan
- National Museum of Marine Biology and Aquarium, Taiwan, Republic of China
| | - Erik C. Franklin
- Hawaii Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawaii, Kaneohe, Hawaii, United States of America
| | - Kevin Gross
- Biomathematics Program, North Carolina State University, Raleigh, North Carolina, United States of America
| | - Xueying Han
- Department of Ecology, Evolution and Marine Biology and the Coastal Research Center, Marine Science Institute, University of California Santa Barbara, Santa Barbara, California, United States of America
- National Center for Ecological Analysis and Synthesis, Santa Barbara, California, United States of America
| | - Lianne Jacobson
- Department of Biology, California State University Northridge, Northridge, California, United States of America
- Department of Biology, University of Florida, Gainesville, Florida, United States of America
| | - James S. Klaus
- Department of Geological Sciences, University of Miami, Coral Gables, Florida, United States of America
| | - Tim R. McClanahan
- Wildlife Conservation Society, Marine Program, Bronx, New York, United States of America
| | - Jennifer K. O'Leary
- National Center for Ecological Analysis and Synthesis, Santa Barbara, California, United States of America
| | | | | | - Hollie M. Putnam
- Hawaii Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawaii, Kaneohe, Hawaii, United States of America
| | - Tyler B. Smith
- Center for Marine and Environmental Studies, University of the Virgin Islands, St. Thomas, Virgin Islands, United States of America
| | - Michael Stat
- The University of Western Australia Oceans Institute and the Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Crawley, Western Australia, Australia
| | - Hugh Sweatman
- Australian Institute of Marine Science, Townsville, Queensland, Australia
| | - Robert van Woesik
- Department of Biological Sciences, Florida Institute of Technology, Melbourne, Florida, United States of America
| | - Ruth D. Gates
- Hawaii Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawaii, Kaneohe, Hawaii, United States of America
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Ramsby BD, Shirur KP, Iglesias-Prieto R, Goulet TL. Symbiodinium photosynthesis in Caribbean octocorals. PLoS One 2014; 9:e106419. [PMID: 25192405 PMCID: PMC4156329 DOI: 10.1371/journal.pone.0106419] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 08/06/2014] [Indexed: 01/17/2023] Open
Abstract
Symbioses with the dinoflagellate Symbiodinium form the foundation of tropical coral reef communities. Symbiodinium photosynthesis fuels the growth of an array of marine invertebrates, including cnidarians such as scleractinian corals and octocorals (e.g., gorgonian and soft corals). Studies examining the symbioses between Caribbean gorgonian corals and Symbiodinium are sparse, even though gorgonian corals blanket the landscape of Caribbean coral reefs. The objective of this study was to compare photosynthetic characteristics of Symbiodinium in four common Caribbean gorgonian species: Pterogorgia anceps, Eunicea tourneforti, Pseudoplexaura porosa, and Pseudoplexaura wagenaari. Symbiodinium associated with these four species exhibited differences in Symbiodinium density, chlorophyll a per cell, light absorption by chlorophyll a, and rates of photosynthetic oxygen production. The two Pseudoplexaura species had higher Symbiodinium densities and chlorophyll a per Symbiodinium cell but lower chlorophyll a specific absorption compared to P. anceps and E. tourneforti. Consequently, P. porosa and P. wagenaari had the highest average photosynthetic rates per cm2 but the lowest average photosynthetic rates per Symbiodinium cell or chlorophyll a. With the exception of Symbiodinium from E. tourneforti, isolated Symbiodinium did not photosynthesize at the same rate as Symbiodinium in hospite. Differences in Symbiodinium photosynthetic performance could not be attributed to Symbiodinium type. All P. anceps (n = 9) and P. wagenaari (n = 6) colonies, in addition to one E. tourneforti and three P. porosa colonies, associated with Symbiodinium type B1. The B1 Symbiodinium from these four gorgonian species did not cluster with lineages of B1 Symbiodinium from scleractinian corals. The remaining eight E. tourneforti colonies harbored Symbiodinium type B1L, while six P. porosa colonies harbored type B1i. Understanding the symbioses between gorgonian corals and Symbiodinium will aid in deciphering why gorgonian corals dominate many Caribbean reefs.
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Affiliation(s)
- Blake D. Ramsby
- Department of Biology, University of Mississippi, University, Mississippi, United States of America
| | - Kartick P. Shirur
- Department of Biology, University of Mississippi, University, Mississippi, United States of America
| | - Roberto Iglesias-Prieto
- Unidad Académica de Sistemas Arrecifales (Puerto Morelos), Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Cancún, México
| | - Tamar L. Goulet
- Department of Biology, University of Mississippi, University, Mississippi, United States of America
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