Settlement of Mytilus galloprovincialis in settlement assays with no choice between polypropylene (PP) surfaces.

Number of mussels (%) settled on test surfaces (smooth PP, textured PP, rope) and glass beaker and suspended in the water column after 48 h. Settlement assays were conducted with mussels (A) 22 days, (B) 30 days, and (C) 38 days post fertilisation. Means ± SE are shown (n = 10). Superscript letters indicate significant differences between test surfaces (pair-wise a posterior test, α = 0.05).