Coral Recruitment on a Local Scale in Amitori Bay, Iriomote Island, Estimated by Filed Surveys and Numerical Analyses
Recruitment of new individuals is essential for community sustainability and resilience. Spatial variation in coral recruitment was quantified for nine sites in Amitori Bay of Iriomote Island, Okinawa Prefecture, Japan, and compared with adult abundance. In addition, potential source sites for recruits, larval trajectories from source to sink sites, and travel distances of larvae were estimated by numerical modeling using real biological and physical data at the main spawning periods. As a result, acroporid recruitment was dominant in Amitori Bay and was positively correlated with adult abundance. Numerical modeling demonstrated a potential that recruits in Amitori Bay could be originated from nearby areas, and that most of recruits traveled less than 400 m with the maximum travel distance of less than 5.5 km. Therefore, estimated dispersal distance of larvae could be relatively short as the mouth of Amitori Bay is about 2 km across and the length of the bay is 4 km. These suggested that the acroporid community in Amitori Bay could be maintained by recruits from within the bay and from immediately surrounding areas.
KeywordsCoral Acropora Recruitment Dispersal Numerical model
We are very grateful to Wataru Noda and Yusuke Matsushita for helping to conduct this research. This study was supported by JSPS KAKENHI Grant Numbers 16K07527. We also thank OIST’s technical editor, Dr. Steven D. Aird, for helping to polish this manuscript.
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