Aquaculture America 2020

February 9 - 12, 2020

Honolulu, Hawaii

UNDERSTANDING THE IMPORTANCE OF SUBSTRATE STABILITY FOR CORAL RESTORATION AND THE PROPOSAL OF 3D-PRINTED REEF TILES FOR INCREASING RESTORATION SUCCESS

Yu V.P.F.*, Pei Y.D.,  Lange C.J.,  Pierce J., Webster C.J., Lau C.P.L., Chan L.K. and Baker D.M.
 
School of Biological Sciences and Swire Institute of Marine Science,
The University of Hong Kong
 Hong Kong SAR
vrikoy@gmail.com
 

Some have suggested that the sub-tropics will become critical habitat for coral reef development under future climate change scenarios. Currently home to marginal reefs, the subtropics are characterized by limited light penetration, extreme temperature fluctuation, salinities, or nutrient levels, conditions further exacerbated by urbanization. Nutrients accelerate bio-erosion by grazers, microborers, and macroborers which abrade corals and threaten their structural integrity. In respon se to a large-scale severe partial mortality event  accelerated by  the subsequent bioerosion from grazing by Diadema setosum , a restoration plan was implemented to rescue the Platygyra populations in Hoi Ha Wan Marine Park (HHWMP) in Hong Kong in 2016.   A restoration study was initiated to make use of the healthy living tissues from thirty bioeroded Platygyra colonies from which they selected and reared on the nursery platform on the seabed for about a year and transplanted at three sites within Hoi Ha Wan Marine Park .   We found that the survivorship of the transplanted fragments was significantly higher at sites with higher substrate stability (i.e. lower percentage cover of rubble).  The results suggested that  substrate stability needs to be improved prior to transplantation to secure downstream restoration success.  As a pilot project on experimental scale , we  propose to design and deploy  3D-printed reef tiles to stabilize substratum and create tailor-made substrate to enhance  coral restoration succe ss.