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Abstract Interest is growing in developing conservation strategies to restore and maintain coral reef ecosystems in the face of mounting anthropogenic stressors, particularly climate warming and associated mass bleaching events. One such approach is to propagate coral coloniesex situand transplant them to degraded reef areas to augment habitat for reef‐dependent fauna, prevent colonization from spatial competitors, and enhance coral reproductive output. In addition to such “demographic restoration” efforts, manipulating the thermal tolerance of outplanted colonies through assisted relocation, selective breeding, or genetic engineering is being considered for enhancing rates of evolutionary adaptation to warming. Although research into such “assisted evolution” strategies has been growing, their expected performance remains unclear. We evaluated the potential outcomes of demographic restoration and assisted evolution in climate change scenarios using an eco‐evolutionary simulation model. We found that supplementing reefs with pre‐existing genotypes (demographic restoration) offers little climate resilience benefits unless input levels are large and maintained for centuries. Supplementation with thermally resistant colonies was successful at improving coral cover at lower input levels, but only if maintained for at least a century. Overall, we found that, although demographic restoration and assisted evolution have the potential to improve long‐term coral cover, both approaches had a limited impact in preventing severe declines under climate change scenarios. Conversely, with sufficient natural genetic variance and time, corals could readily adapt to warming temperatures, suggesting that restoration approaches focused on building genetic variance may outperform those based solely on introducing heat‐tolerant genotypes.
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Differential incorporation of scientific advances affects coastal habitat restoration practice
Abstract Understanding the diffusion of innovative ideas, behaviors, and technologies could reduce disconnects between conservation science and management, such as the science‐practice gap between biodiversity research and restoration practice. To assess knowledge uptake as an indicator of diffusion of innovation in restoration practice, we conducted an online survey of two organizations focused on coastal habitat restoration: Coastal and Estuarine Research Federation (CERF) and International Coral Reef Society (ICRS). We evaluated experience restoring particular habitats, along with perceptions of the purpose of restoration, the metrics used to evaluate restoration success, and the challenges to successful restoration. We then examined the perceived importance of genetic diversity for restoration success as an indicator of knowledge‐practice transfer in conservation strategy. The practice of coastal habitat restoration diverged by organization and habitat: a higher percentage of CERF members had restored oysters, marshes, and seagrasses compared to ICRS, whereas the reverse was true for corals. Views of the purpose of restoration, the site selection process, and the challenges to successful restoration were similar. Despite similarities in perceptions of the restoration process, the two organizations had variable indications of knowledge‐practice transfer: ICRS respondents ranked the importance of genetic diversity as a restoration strategy higher than did CERF respondents. The perceived importance of genetic diversity also differed by habitat, with both CERF and ICRS respondents ranking diversity as more important for corals. The more successful transfer of knowledge to practice in the coral community indicates that the disconnect between genetic diversity research and restoration practice is surmountable. In addition, it serves as a potential strategy for promoting the spread of innovative restoration practices to achieve long‐term recovery of ecosystems.
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- Award ID(s):
- 1652320
- PAR ID:
- 10455136
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Conservation Science and Practice
- Volume:
- 2
- Issue:
- 12
- ISSN:
- 2578-4854
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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