In recent decades, the transplantation of corals has been a primary focus of restoration strategies in areas where coral populations have declined [1]. Although studies of hard coral (Hexacorallia: Scleractinia) transplantations are far more common, soft coral (Octocorallia: Alcyonacea) transplantation attempts are also promising [2]. Soft coral aggregations provide an important habitat for fish and invertebrates in both temperate and tropical marine environments [3,4], and restoration of these habitats is important for maintaining regional biodiversity.
Port Stephens, a tidal estuary in northern New South Wales (NSW), Australia, is home to a diverse assemblage of filter-feeders, including the threatened soft coral Dendronephthya australis. This soft coral has rapidly declined in the last 10 years [5,6], and is now listed as Endangered in NSW [7]. Dendronephthya australis aggregations support unique faunal assemblages that include juveniles of the fishery—important pink snapper (Chrysophrys auratus) and the Endangered White’s seahorse (Hippocampus whitei) [3,8].
To assist the recovery of D. australis, we are trialling laboratory rearing of cuttings (nubbins) with subsequent transplantation into suitable habitats. In the first trial, we recorded rapid colonisation of almost half (22) of the 48 nubbins by invertebrates. Within 24 h, two sponge decorator crabs Hyastenus elatus (Figure 1B) had colonised fragments. After 13 d, a species of ovulid (Ovulidae: Gastropda) (Globovula cavanaghi) was found feeding on a nubbin. Two other species of ovulid (shown in Figure 1A,D), the trochid gastropod Astele scitula (Figure 1C), and the heterobranch sea slug Dermatobranchus sp. (Figure 1D) were also found on nubbins within six weeks of deployment. These species are known to display a preference for soft coral habitats [9,10]. These preliminary results suggest great potential for D. australis transplantation programs to have positive impacts on biodiversity within the Port Stephens estuary.
Enlarge this image.Figure 1. Example of species recruiting to transplanted nubbins of D. australis. (A): Diminovula culmen; (B): Hyastenus elatus; (C): Astele scitula; (D): Dermatobranchus sp., Testudovolva nebula.
Author Contributions
Conceptualization, M.F.L., D.H., S.D.A.S. and T.R.D.; methodology, M.F.L.; software, M.F.L.; validation, M.F.L., D.H., S.D.A.S. and T.R.D.; formal analysis, M.F.L.; investigation, M.F.L.; resources, M.F.L. and D.H.; data curation, M.F.L.; writing-original draft preparation, M.F.L.; writing-review and editing, M.F.L., D.H., S.D.A.S. and T.R.D.; visualization, M.F.L.; supervision, D.H., S.D.A.S. and T.R.D.; project administration, M.F.L., D.H., and S.D.A.S.; funding acquisition, D.H., and M.F.L. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by the NSW Department of Primary Industries (DPI), the Marine Ecology Research Centre, Southern Cross University, and the Australian Government Research Training Program Scholarship. Data collection was undertaken in accordance with NSW DPI permit: P01/0059(A)-4.0 and Marine Parks permit: PSGLMP 2018/10 and 2018/15.
Institutional Review Board Statement
Ethical review and approval were waived for this research, due to the study of invertebrates only.
Acknowledgments
We thank Christopher Westley and Gwenael Cadiou for their valuable assistance in the field. Many thanks also to Bennan Chen and Madeleine Tresselt for their help in the laboratory component of this study.
Conflicts of Interest
The authors declare no conflict of interest.
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Meryl F. Larkin
1,2,*,
David Harasti
3,
Tom R. Davis
4 and
Stephen D. A. Smith
1,2
1National Marine Science Centre, Southern Cross University, Bay Drive, Coffs Harbour, NSW 2450, Australia
2Marine Ecology Research Centre, Southern Cross University, Lismore, NSW 2480, Australia
3Fisheries Research, Marine Ecosystems, NSW Department of Primary Industries, Taylors Beach, NSW 2316, Australia
4Fisheries Research, NSW Department of Primary Industries, P.O. Box 4321, Coffs Harbour, NSW 2450, Australia
*Author to whom correspondence should be addressed.
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