dissimilarities arose between the small size and the other two size classes (Fig. 4). Regardless of size, a distinct feeding pattern was observed under the 12 h light/12 h dark cycle, as indicated by feeding proportions. More sea cucumbers fed at night (20:00–08:00) than during the day (08:00–20:00). The small and medium-sized groups had a feeding peak at 02:00–04:00 and the feeding peak of large sea cucumbers was between 02:00 and 06:00. In addition, the medium and large-sized groups had a second feeding peak at 10:00–16:00 (Fig. 4). The results also revealed a significant interaction between time and size with respect to feeding proportion (Table 2).