In this era of global climate change, understanding fundamental mechanisms of coral community maintenance and persistence in temperate non-reefal areas is a high marine conservation priority. To identify mechanisms of community maintenance and persistence via larval supply, we monitored coral settlement over 12 years and investigated the genetic population structure of two major acroporid species at Kushimoto, Wakayama Prefecture, Japan (33°N). Between 8 and 30 artificial settlement panel pairs were deployed from May or June to September, October, or November of each year. Recruits on settlement panel pairs were scarce, especially those of acroporids (0 or < 1 recruit per panel pair in most years). As coral cover in the Kushimoto area remained relatively high over a decade, such low recruitment may be sufficient for persistence of acroporid communities in this region. In addition, genetic analysis using 8 or 10 microsatellite markers demonstrated differences in genetic structure between populations of Acropora hyacinthus, which is a long-term resident species in this area, and A. muricata, a recently arrived species. Acropora hyacinthus displayed higher numbers of multilocus genotypes (41 of 43 samples collected) whereas only one multilocus genotype in 30 samples was seen in A. muricata. This difference may reflect both the length of time since population establishment and morphology. Consequently, acroporid communities in the Kushimoto area are likely maintained by survival and growth of existing colonies and/or fragmentation, indicating that conservation of established corals should be the first priority to ensure persistence of coral assemblages in such temperate non-reefal areas.

在这个全球气候变化的时代，了解温带非珊瑚礁地区珊瑚群落维持和持久性的基本机制是海洋保护的高度优先事项。为了通过幼虫供应确定群落维持和持久性的机制，我们监测了 12 年的珊瑚沉降，并调查了日本和歌山县 Kushimoto（33°N）的两种主要顶峰动物的遗传种群结构。从每年的 5 月或 6 月到 9 月、10 月或 11 月，部署了 8 到 30 个人工沉降面板对。定居小组对上的新兵很少，尤其是顶峰动物（大多数年份每对小组招募 0 或 < 1 名）。由于串本地区的珊瑚覆盖率在过去十年中保持相对较高，如此低的招募可能足以维持该地区的顶峰群落。此外，使用 8 或 10 个微卫星标记的遗传分析表明，不同种群之间的遗传结构存在差异。Acropora hyacinthus是该地区的长期栖息物种，A . muricata，一种最近到达的物种。Acropora hyacinthus显示出更多的多位点基因型（收集的 43 个样本中的 41 个），而在A中仅观察到 30 个样本中的一个多位点基因型。柃。这种差异可能反映了自种群建立以来的时间长度和形态。因此，串本地区的顶峰群落很可能通过现有群落的生存和生长和/或破碎来维持，这表明保护已建立的珊瑚应该是确保这些温带非珊瑚礁地区珊瑚群落持续存在的首要任务。