string: The site is characterized by a mix of sand and cobble substrate and a gentle descent to depth (for detailed descriptions of the study site, see Balshine-Earn et al. 1998; Balshine et al. 2001; Bergmüller et al. 2005; Dierkes et al. 2005; Heg et al. 2005; Stiver et al. 2005; Wong et al. 2012).