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Overton K, Dempster T, Swearer SE, Morris RL, Barrett LT. Achieving conservation and restoration outcomes through ecologically beneficial aquaculture. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024; 38:e14065. [PMID: 36811200 DOI: 10.1111/cobi.14065] [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: 05/22/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
A range of conservation and restoration tools are needed to safeguard the structure and function of aquatic ecosystems. Aquaculture, the culturing of aquatic organisms, often contributes to the numerous stressors that aquatic ecosystems face, yet some aquaculture activities can also deliver ecological benefits. We reviewed the literature on aquaculture activities that may contribute to conservation and restoration outcomes, either by enhancing the persistence or recovery of one or more target species or by moving aquatic ecosystems toward a target state. We identified 12 ecologically beneficial outcomes achievable via aquaculture: species recovery, habitat restoration, habitat rehabilitation, habitat protection, bioremediation, assisted evolution, climate change mitigation, wild harvest replacement, coastal defense, removal of overabundant species, biological control, and ex situ conservation. This list may be expanded as new applications are discovered. Positive intentions do not guarantee positive ecological outcomes, so it is critical that potentially ecologically beneficial aquaculture activities be evaluated via clear and measurable indicators of success to reduce potential abuse by greenwashing. Unanimity on outcomes, indicators, and related terminology will bring the field of aquaculture-environment interactions into line with consensus standards in conservation and restoration ecology. Broad consensus will also aid the development of future certification schemes for ecologically beneficial aquaculture.
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Affiliation(s)
- Kathy Overton
- Sustainable Aquaculture Laboratory - Temperate and Tropical (SALTT), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
- National Centre for Coasts and Climate (NCCC), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
- Coastal and Estuarine Adaptation Lab, School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Tim Dempster
- Sustainable Aquaculture Laboratory - Temperate and Tropical (SALTT), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
- National Centre for Coasts and Climate (NCCC), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Stephen E Swearer
- National Centre for Coasts and Climate (NCCC), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Rebecca L Morris
- National Centre for Coasts and Climate (NCCC), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
- Coastal and Estuarine Adaptation Lab, School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Luke T Barrett
- Sustainable Aquaculture Laboratory - Temperate and Tropical (SALTT), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
- National Centre for Coasts and Climate (NCCC), School of BioSciences, University of Melbourne, Melbourne, Victoria, Australia
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A novel system for intensive Diadema antillarum propagation as a step towards population enhancement. Sci Rep 2021; 11:11244. [PMID: 34045538 PMCID: PMC8160213 DOI: 10.1038/s41598-021-90564-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 05/12/2021] [Indexed: 02/04/2023] Open
Abstract
The long-spined sea urchin Diadema antillarum was once an abundant reef grazing herbivore throughout the Caribbean. During the early 1980s, D. antillarum populations were reduced by > 93% due to an undescribed disease. This event resulted in a lack of functional reef herbivory and contributed to ongoing ecological shifts from hard coral towards macroalgae dominated reefs. Limited natural recovery has increased interest in a range of strategies for augmenting herbivory. An area of focus has been developing scalable ex situ methods for rearing D. antillarum from gametes. The ultimate use of such a tool would be exploring hatchery origin restocking strategies. Intensive ex situ aquaculture is a potentially viable, yet difficult, method for producing D. antillarum at scales necessary to facilitate restocking. Here we describe a purpose-built, novel recirculating aquaculture system and the broodstock management and larval culture process that has produced multiple D. antillarum cohorts, and which has the potential for practical application in a dedicated hatchery setting. Adult animals held in captivity can be induced to spawn year-round, with some evidence for annual and lunar periodicity. Fecundity and fertilization rates are both consistently very high, yet challenges persist in both late stage larval development and early post-settlement survival. Initial success was realized with production of 100 juvenile D. antillarum from ~ 1200 competent larvae. While the system we describe requires a significant level of investment and technical expertise, this work advances D. antillarum culture efforts in potential future hatchery settings and improves the viability of scalable ex situ production for population enhancement.
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