Susswein A J, Gev S, Feldman E, Markovich S
Behav Neural Biol. 1983 Nov;39(2):203-20. doi: 10.1016/s0163-1047(83)90859-2.
Activity patterns of Aplysia fasciata were observed in a protected port environment and in an aquarium. In both, major activities were feeding and mating, which collectively took up about 45% of the total time of the animals. Active behaviors occurred primarily at night; much of the day was spent in the inactive state. Activities were highly synchronized, with large numbers of animals performing the same behaviors simultaneously at a specific time. Mating and eating occurred primarily at different times; relatively few animals were observed performing these behaviors simultaneously. Many animals laying eggs were simultaneously mating as females.