As Hawkins et
al. (1998a) pointed out, it is necessary to note that these calculations assume no
significant delay in the deposition of filtered particles, estimating particle availability as
the integrated average over corresponding periods of faecal collection. From the above
experimental design, it is obvious that the determination of seston characteristics is
actually discontinuous, whereas feeding activity is continuous. Therefore, the data
obtained in this experiment were actually a pool of estimated mean values. To determine
temporal variations in seston availability and feeding responses, each tidal cycle is
equally divided into three phases, namely low, mid and high tides, according to the
height the water reached (Fig. 1).