Analysis of behavioural rejection of micro-textured surfaces and implications for recruitment by the barnacle Balanus improvisus

Experiments performed in the field and in the laboratory show that the barn acle, Balanus improvisus, preferentially settles on smooth surfaces. Settle ment and recruitment of B. improvisus was evaluated on micro-textured surfa ces with scales of surface texture ranging from 1 to 100 mu m in profile he ights. Surface texture with profile heights within a topographic range of 3 0-45 mu m reduced settlement and recruitment by 92% as compared to smooth s urfaces. The reduction in recruitment on micro-textured surfaces is best ex plained by behavioural responses to surface topography. Behavioural experim ents show that cyprids have a higher propensity for smooth surfaces than fo r micro-textured surfaces. Cyprids spend more time exploring smooth surface s and more time swimming when exposed to micro-textured surfaces. Micro-tex tured surfaces are more often rejected by cyprids after exploration than sm ooth surfaces. It is suggested that some scales of surface texture could be exploited to improve future anti-fouling techniques in geographical areas where Balanus improvisus is a severe fouling problem. (C) 2000 Elsevier Sci ence B.V. All rights reserved.