Field-based video observations of wild barnacle cyprid behaviour in response to textural and chemical settlement cues

Abstract

Many marine invertebrate larvae respond behaviourally to environmental settlement cues, yet behaviours are often only inferred from settlement patterns or are limited to laboratory studies. The behaviour of wild cypris larvae of Semibalanus balanoides L. was filmed on settlement tiles in the field. Tiles were of five different textures with a nested treatment of crude conspecific adult extract (AE). The effects of texture and AE on eleven defined behaviours were analysed. Texture affected the gross and net exploratory distances, velocity, acceleration and time spent exploring. AE attracted more cyprids during the first minute of immersion and increased the time spent on surfaces. Relatively few arrivals that either travel far and fast, or exit the surface rapidly, may indicate a lower chance of settlement. An increase in time spent on a surface may increase the probability of being in contact with the surface when the sign stimulus to settle occurs.

Surface Sensing and Settlement Strategies of Marine Biofouling Organisms

“…As already observed by Schumacher et al [100], Aldred et al [99] and in field experiments by Prendergast et al [98], surface morphology affects exploration and settlement. Chaw et al [104] described the behavior of Amphibalanus amphitrite over a pattern of cylindrical micropillars with heights of 5 and 30 lm, a separation of 10 lm and diameters ranging from 5 to 100 lm.…”

“…The behavior of wild cyprid larvae of Semibalanus balanoides in situ in the ocean close to different surface textures treated and untreated with crude conspecific adult extract (AE) has been studied by Prendergast et al [98]. The treatment with AE produces an increase in the number of cyprids arriving on the surface both, within the first minute and after a longer time.…”

Classification of the pre-settlement behaviour of barnacle cyprids

“…An understanding of this behaviour is not only important to population and community dynamics [14], but also to the development of novel methods to interfere with and inhibit the settlement of cyprids [15]. The desire to understand the surface selection strategies of cyprids has led to development of two-dimensional video tracking methods to quantify cyprid motions [14,[16][17][18][19][20][21] and novel surface-sensitive imaging techniques [22,23]. Two-dimensional tracking was used previously to identify motion patterns of cyprids inspecting substrata [10,14,[16][17][18]20,21,24].…”

“…Surface structure and texture were also proven to influence the cyprid behaviour in terms of quantitative parameters (e.g. velocity, 'net travelled distance' and acceleration) [20]. In the walking phase, where cyprids use their antennules to move slowly across surfaces, differences in the step duration and length were found when different chemical surface terminations were compared [18].…”

Imaging SPR combined with stereoscopic 3D tracking to study barnacle cyprid–surface interactions

“…Surfaces become colonized by the larval stage of barnacles, cyprids, (Aldred and Clare 2008) and these cyprids show settlement preferences in so far as they select surfaces suitable for settlement and reject unsuitable ones (Aldred and Clare 2008). Video tracking allows observation and analysis of the motion of larvae and thus insight into their pre-settlement behavior (Lagersson and Høeg 2002, Marechal, Hellio et al 2004, Prendergast, Zurn et al 2008, Aldred, Li et al 2010. Stereoscopic tracking adds the missing third dimension, required for calculation of parameters such as velocity and directedness, and enables a detailed analysis of cyprid distributions and swimming parameters as function of coating properties (Maleschlijski, Bauer et al 2014, Maleschlijski, Bauer et al 2015.…”