Surface exploration of Amphibalanus amphitrite cyprids on microtextured surfaces

Abstract

Microtopography is one of several strategies used by marine organisms to inhibit colonization by fouling organisms. While replicates of natural microtextures discourage settlement, details of larval interactions with the structured surfaces remain scarce. Close-range microscopy was used to quantify the exploration of cyprids of Amphibalanus amphitrite on cylindrical micropillars with heights of 5 and 30 μm and diameters ranging from 5 to 100 μm. While 5 μm-high structures had little impact, 30 μm-high pillars significantly influenced cyprid exploration. An observed step length decrease and step duration increase on 5 μm diameter pillars is attributed to the small dimensions of the voids excluding the cyprid's attachment disc and consequently reducing the area of adhesive contact. When exploring larger diameter pillars, cyprids preferred using the voids to form temporary attachment points. This may enhance their resistance to flow. No-choice assay settlement patterns mirrored this exploration behaviour, albeit in a pattern counter to what was predicted.

Keywords:

• Amphibalanus amphitrite
• cypris larva, surface exploration behaviour
• microtextured surfaces
• behavioural assay

Acknowledgements

This work was supported by the Science and Engineering Research Council (SERC), A*STAR, Singapore. GHD was supported by the US Office of Naval Research, award N000140811025 to the Tropical Marine Science Institute, National University of Singapore. The authors would like to thank Dr Serena Teo, Mr Seng Tiong Ang and Ms Lee Fan Gan for barnacle cyprids. The authors thank the anonymous reviewers for their valuable comments and suggestions.