Strong horizontal and vertical connectivity in the coral Pocillopora verrucosa from Ludao, Taiwan, a small oceanic island

PLoS One. 2021 Oct 11;16(10):e0258181. doi: 10.1371/journal.pone.0258181. eCollection 2021.

Abstract

Mesophotic habitats could be sheltered from natural and anthropogenic disturbances and act as reproductive refuges, providing propagules to replenish shallower populations. Molecular markers can be used as proxies evaluating the connectivity and inferring population structure and larval dispersal. This study characterizes population structure as well as horizontal and vertical genetic connectivity of the broadcasting coral Pocillopora verrucosa from Ludao, a small oceanic island off the eastern coast of Taiwan. We genotyped 75 P. verrucosa specimens from three sites (Gongguan, Dabaisha, and Guiwan) at three depth ranges (Shallow: 7-15 m, Mid-depth: 23-30 m, and Deep: 38-45 m), spanning shallow to upper mesophotic coral reefs, with eight microsatellite markers. F-statistics showed a moderate differentiation (FST = 0.106, p<0.05) between two adjacent locations (Dabaisha 23-30 and Dabaisha 38-45 m), but no differentiation elsewhere, suggesting high levels of connectivity among sites and depths. STRUCTURE analysis showed no genetic clustering among sites or depths, indicating that all Pocillopora individuals could be drawn from a single panmictic population. Simulations of recent migration assigned 30 individuals (40%) to a different location from where they were collected. Among them, 1/3 were assigned to deeper locations, 1/3 to shallower populations and 1/3 were assigned to the right depth but a different site. These results suggest high levels of vertical and horizontal connectivity, which could enhance the recovery of P. verrucosa following disturbances around Ludao, a feature that agrees with demographic studies portraying this species as an opportunistic scleractinian.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anthozoa / genetics*
  • Genetic Loci
  • Genetic Variation
  • Geography
  • Islands*
  • Microsatellite Repeats / genetics
  • Oceans and Seas*
  • Principal Component Analysis
  • Probability
  • Taiwan

Grants and funding

This study was funded by the Taiwanese Ministry of Science and Technology to CAC (MOST 103-2621-B-001-004-MY3) and VD (MOST 104-2611-M002-020-MY2). SDP is currently the recipient of a Ministry of Science and Technology postdoctoral grant (MOST 110-2811-M-002-514). SDP and DS were both supported by the Taiwan International Graduate Program (BIODIV 23-14 to SDP and DS) and the Coral Reef Ecology and Evolutionary Genetics laboratory. The funders had no role in the study design.