Effects of initial surface wettability on biofilm formation and subsequent settlement of Hydroides elegans

Abstract

Hydroides elegans is a major fouling organism in tropical waters around the world, including Pearl Harbor, Hawaii. To determine the importance of initial surface characteristics on biofilm community composition and subsequent colonization by larvae of H. elegans, the settlement and recruitment of larvae to biofilmed surfaces with six different initial surface wettabilities were tested in Pearl Harbor. Biofilm community composition, as determined by a combined approach of denaturing gradient gel electrophoresis and fluorescence in situ hybridization, was similar across all surfaces, regardless of initial wettability, and all surfaces had distinct temporal shifts in community structure over a 10 day period. Larvae settled and recruited in higher numbers to surfaces with medium to low wettability in both May and August, and also to slides with high wettability in August. Pearl Harbor biofilm communities developed similarly on a range of surface wettabilities, and after 10 days in Pearl Harbor all surfaces were equally attractive to larvae of Hydroides elegans, regardless of initial surface properties.

Keywords:

• Hydroides elegans
• larval settlement
• biofouling
• biofilm
• wettability
• hydrophobicity
• tube worm

Acknowledgements

Authors thank Dr Eric Holm for contact angle measurements and helpful discussions, and Timothy DuBuc, Sherrilyn Kanno and Kimberly Conklin for assistance in the field and the laboratory. This research was supported by grant no. N00014-05-1-0579 from the US Office of Naval Research to MGH. Comments from two anonymous reviewers helped to improve the manuscript.