Reef location and season, but not recruitment substrate contour and composition, affect coral recruitment patterns

Abstract

Most studies have quantified coral recruitment using recruitment tiles temporarily deployed on reefs. However, the wide range of tile types used in different studies potentially influences recruitment patterns thereby hindering accurate comparisons among reef areas. We examined the effect of different tile types with different surface structure and composition on spatial (reef locations) and temporal (season) patterns of coral recruitment in the northwestern Philippines. Dead coral skeleton, terracotta, and fibre-cement tiles were deployed and retrieved quarterly over a 15-month period. In contrast to previous studies, patterns of standardized density and composition of recruits were consistent among tile types. Recruits varied spatially and were highest in Caniogan reef, followed by Cory reef and Lucero reef, suggesting that coral recruitment in the Bolinao-Anda Reef Complex (BARC) is influenced by reef location and existing coral cover. Highest recruitment was also found during the peak coral spawning season. The results of this study contrast with some previous reports which indicate that coral recruitment patterns are strongly influenced by recruitment substrate types. Our study suggests that once sufficient biological conditioning of the tile surfaces has occurred, the microbial and algal community present on the different tile surfaces are similarly conducive to larval settlement of some coral taxa.